JP4361383B2 - Light intensity distribution monitoring method, annealing apparatus, annealing method, and crystallization apparatus - Google Patents

Description

The present invention is, for example, an excimer laser annealing apparatus, a YAG laser apparatus (including higher harmonics), an excimer lamp, an i-line lamp, a g-line lamp, and an Xe lamp for heating, activating impurities, or crystallizing a semiconductor thin film. The present invention also relates to a light intensity distribution monitoring method , an annealing apparatus, an annealing method , and a crystallization apparatus that are particularly effective when applied to detection of a light intensity distribution when irradiating a minute region with invisible light such as a copper vapor laser apparatus.

  In a display device such as an active matrix liquid crystal display device or an organic EL display device, a number of thin film transistors (TFTs) are formed on an insulating substrate such as glass or plastic in order to drive each pixel individually. Among silicon films used for TFT source, drain, and channel regions, amorphous silicon (a-Si) films have a low formation temperature and can be formed relatively easily by a vapor phase method. Therefore, it is generally used as a semiconductor thin film used for TFT. However, a-Si films are inferior to crystalline polycrystalline silicon (poly-Si) films in terms of electrical conductivity, etc. (the mobility of a-Si is two orders of magnitude lower than that of poly-Si) Due to the drawbacks, in order to increase the operating speed of the TFT in the future, it is necessary to establish a manufacturing method using a poly-Si film having crystallinity as the source, drain and channel regions of the TFT.

  At present, as a method for forming a poly-Si film, for example, excimer laser annealing (hereinafter referred to as ELA method) described in Non-Patent Document 1 can be used in a temperature range (room temperature to 500 ° C.). To the extent). In the ELA method, an a-Si film is mainly formed on a substrate to a predetermined thickness (for example, about 50 nm), and then a krypton fluorine (KrF) excimer laser beam (wavelength 248 nm) or Xenon chlorine (XeCl) excimer laser light (wavelength 308 nm) is used for the technique of melting by irradiation and changing to a poly-Si film. The ELA method can be applied to various other processes by changing the intensity of laser light. For example, if the intensity of the laser beam is lowered, only the action of heating is obtained, and it can be used for an impurity activation process necessary for manufacturing a TFT. Further, if the intensity of the laser beam is extremely increased, a rapid temperature rise is caused, and therefore, it can be used for removing a film in the TFT. Note that the use of these phenomena is not limited to TFTs, but can be widely applied to semiconductor processes.

  By the way, the defects present in the crystal grain boundaries of the poly-Si film significantly increase the variation in the threshold voltage Vth of the TFT and cause a significant deterioration in the operating characteristics of the entire display device. For this reason, each TFT is required to reduce crystal grain boundaries in each channel region as much as possible. In order to reduce the crystal grain boundaries as much as possible, it was found that the design of the light intensity distribution, which is the light intensity distribution of the laser light applied to the a-Si film, is extremely important. However, it is very difficult to accurately measure invisible light such as excimer laser light irradiated on a very small region in units of microns, and a measurement technique for that purpose has not yet been established.

  Up to now, in order to detect the light intensity distribution of invisible light, place the substance whose physical properties change with respect to the light intensity to be detected and evaluate it by causing chemical or physical changes. The “method” was mainly used. For example, in the exposure technology in the photolithography process of semiconductor device manufacturing, in order to confirm the light intensity distribution of ultraviolet rays such as i-line and g-line, a resist is applied to the irradiated surface and this is irradiated with ultraviolet rays to cause a chemical reaction. The light intensity distribution evaluation method based on the change in physical properties is employed, in which the development is further performed and the resist film shape after development is observed.

In the ELA method, as shown in Non-Patent Document 1, laser light is emitted at a threshold light intensity (fluence) that induces crystallization (poly-Si film formation) in the target a-Si film. When irradiated, it becomes poly-Si only where the light intensity distribution is strong, and the physical properties change partially. A method of observing a crystallized structure reflecting the light intensity distribution as described above, that is, a method of confirming the light intensity distribution of a laser by evaluation based on changes in physical properties is generally used. In addition, a method of predicting the light intensity distribution based on the physical constants relating to the laser light examined in advance has been taken.
Surface Science Vol. 21, no. 5, pp 278-287 (2000)

  However, the conventional methods for evaluating the light intensity distribution due to changes in physical properties have the following problems (i) and (ii).

  (I) Materials that change their physical properties (for example, resist, thin film a-Si, etc.) tend to cause variations in the physical properties of the material to be analyzed.

  (Ii) Since it is an off-line inspection for observing changes in physical properties, the detection result of the light intensity distribution cannot be directly known.

  For example, in the conventional light intensity distribution evaluation method in the ELA method, the substrate is taken out after laser irradiation and the shape of the crystallized structure of the thin film semiconductor is confirmed using an optical microscope or the like, but the substrate is taken out from the laser annealing apparatus. Because of this, it takes a very long time.

The present invention has been made to solve the above-described problems, and is a light intensity distribution monitoring method capable of stably detecting a measurement result without variation even when a material whose physical properties change is targeted. An annealing apparatus, an annealing method , and a crystallization apparatus are provided.

In addition, the magnifying optical system is easy to adjust, the image plane to be detected (such as the focus plane of the annealing device) can be easily identified, and the low-cost light intensity distribution monitoring method , annealing device, and annealing that can obtain measurement results in real time It is an object to provide a method and a crystallization apparatus .

The present inventors have developed a crystallization technique having a size capable of forming one or a plurality of TFT transistors. In this development, in order to perform uniform and reliable crystallization on a large surface of about several centimeters to several tens of centimeters like a display device, the present inventor has applied laser light to irradiate an a-Si film. It was found that the design and monitoring of the light intensity distribution, which is the light intensity distribution, is extremely important. That is, it has been found that crystallization by a stable light intensity distribution is extremely effective for forming a stable crystallization region without variation. The present invention provides a light intensity distribution monitoring method, a light intensity distribution monitoring apparatus , an annealing apparatus, an annealing method , and a crystallization apparatus that can stably detect the light intensity distribution without variation.

The light intensity distribution monitoring method according to the present invention includes a laser light source, an image forming optical system provided on an optical axis of laser light from the laser light source, and an image forming position of the image forming optical system. An XYZ stage that movably supports a substrate to be treated, whose surface to be irradiated is annealed, a wavelength conversion member that converts the laser light into visible light, and a wavelength conversion member that are displayed on the wavelength conversion member A magnification optical system having an imaging device that magnifies and captures a visible light image, and a height sensor that measures a relative height position of a substrate to be processed on the XYZ stage with respect to the imaging optical system. When monitoring the light intensity distribution of the laser beam that anneals the substrate to be processed using the laser annealing apparatus provided,
Trisodium 8-hydroxy-1,3,6-pyrenetris having a desired spatial resolution for displaying the light intensity distribution image of visible light by converting the laser light into visible light at the position of the substrate to be processed A step of installing a wavelength conversion member containing rufonate;
By measuring the height position of the wavelength conversion member installed at the position of the substrate to be processed with the height sensor and adjusting the height position to be stored in advance, the wavelength conversion member is flush with the substrate to be processed. Aligning the
A step of emitting from the laser light source a laser light selected from an energy amount of the laser light from the laser light source selected so that the wavelength conversion member does not deteriorate or evaporate;
Imaging a light intensity distribution image of visible light displayed on the wavelength conversion member with an imaging device;
First, a light intensity distribution image of visible light in which the light intensity distribution of laser light to be annealed on the substrate to be processed is displayed on the wavelength conversion member is picked up by an imaging device , and the light intensity and light intensity distribution image of the laser light are captured. And detecting the detection result as a target value in advance and storing it,
And the imaging in order to control the height position of the wavelength conversion member to match the light intensity distribution image and intensity of the target value which the light intensity distribution image and the light intensity is stored in advance taken by the imaging device Monitoring a minute visible light image having a light intensity distribution;
Storing the height position of the wavelength conversion member measured by the height sensor;
The wavelength conversion member is retracted, the substrate to be processed is moved to a position where the wavelength conversion member was present, the stored target value is called, and the substrate to be processed corresponding to the target value from the laser light source And irradiating the substrate to be processed with a laser beam having a light intensity of an energy amount for annealing and a light intensity distribution .

  Furthermore, the invisible light is intermittently irradiated to the wavelength conversion member, and the light intensity distribution of the visible light displayed on the other surface of the wavelength conversion member is detected by the magnifying optical system in synchronization with the intermittent irradiation. Is preferred. Invisible light is attenuated by an attenuator, and the fluence is adjusted so that the optical system and the substrate to be processed are not burned. Nevertheless, continuous irradiation shortens the life of each part of the optical system, and the frequency of component replacement Will increase. By intermittently measuring in synchronization with the intermittent irradiation, it is possible to extend the lifetime of each part of the optical system, particularly the lifetime of the wavelength conversion member.

The size for observing invisible light is required to be about 100 μm × 100 μm, but also requires spatial resolution. This spatial resolution is required to be at least 5 μm or less, more preferably 1 μm or less, and most preferably 0.5 μm or less in order to further improve detection accuracy. It is an observation region of several tens of microns, and it is very difficult to accurately measure the light intensity distribution in such a small region. This is because high spatial resolution (spatial resolution) is required. By the way, the conventional light intensity distribution monitoring device is intended for the macro area, and the size of the detection target area is a unit of several millimeters to several centimeters (for example, 4.5 × 6.0 mm, φ65 mm). The spatial resolution (for example, 10 to 20 μm) is not so high.

On the other hand, for example, in the crystallization process of a silicon thin film using the ELA method, research and development are being carried out with the aim of forming large-sized crystal grains having a diameter of several microns to more than 10 microns in the TFT channel region. The resolution is required to be very high. Usually, it is desirable that the spatial resolution of the light intensity distribution monitoring device is about an order of magnitude smaller than the crystal grain size to be manufactured. This means that a spatial resolution smaller than 1/5 to 1/10 of the crystal grain size to be produced is required. For example, when forming crystal grains having a grain size of 10 μm, a spatial resolution of 1/5 to 1/10, that is, a spatial resolution smaller than 2 μm to 1 μm is required. For this reason, the magnifying optical system needs to include an objective lens capable of clearly enlarging a visible light image and a high-resolution imaging means capable of satisfying the above-described required level, for example, an imaging element (an area sensor CCD). In order to meet such demands, in the present invention, the magnification of the magnifying optical system is preferably in the range of 2 to 2000 times, and most preferably in the range of 100 to 200 times. This is because the size of the observation target region is 100 μm × 100 μm or less.

The wavelength conversion member can include a fluorescent material that can convert ultraviolet light having a center wavelength of, for example, 400 nm or less into visible light. The wavelength conversion member is made of an organic substance (for example, rhodamine B) used in the dye laser. Experimentally, pyranin (Pyranine Conc; C ₁₆ H ₇ Na ₃ O ₁₀ S ₃ ) is optimal as a fluorescent substance. The official scientific name for pyranine is Trisodium 8-hydroxy-1,3,6-pyrenetrisulfonate. The emission intensity of the fluorescent substance in the wavelength conversion member increases in direct proportion depending on the intensity of irradiation light, but is saturated when the light intensity exceeds a certain level. For example, when the intensity of irradiation light is 30 mJ / cm ² or less, the emission intensity of the fluorescent material has a characteristic with good linearity (see FIG. 14). However, if the light intensity is increased excessively, the organic fluorescent material evaporates, so the light intensity cannot be increased unnecessarily.

As a fluorescent material for converting invisible light in the ultraviolet wavelength region to visible light, a thin film of SiO ₂ doped with Tb or Eu in addition to pyranine can be used. There is also a method of applying nanoparticles having a diameter of several tens of nanometers such as CdSe.

  When a YAG laser having a center wavelength of about 1.0 μm is used, a fluorescent material that can convert infrared light having a center wavelength of 780 nm or more into visible light is preferably used for the wavelength conversion member. For such a fluorescent material, YAGLAST (trade name of Sumita Optical Glass Co., Ltd.) suitable for thinning is most suitable.

  The base material holding the wavelength conversion member is preferably made of a material that absorbs or blocks invisible light and transmits only visible light. Furthermore, it is desirable to have a filter that is disposed between the wavelength conversion member and the image sensor and absorbs or blocks invisible light and transmits only visible light. As a material for such a substrate or filter, a multi-coating substrate in which a transparent glass substrate is coated with a plurality of thin films is suitable. The substrate holds the wavelength conversion member, and there are various methods for holding it. The most common holding method is a method of applying a phosphor-containing solution to a substrate. In addition to the coating method, a method of forming a film on a base material by a sputtering method or a CVD method, or a method of polishing after fusing on a base material by a spraying method can be used.

  The average film thickness of the wavelength conversion member is preferably 1 nm or more and 3 μm or less. If the average film thickness of the wavelength conversion member exceeds 3 μm, the spatial resolution decreases, so the upper limit value of the film thickness is 3 μm. On the other hand, if the film thickness of the wavelength conversion member, for example, the wavelength conversion member is made thinner than 1 nm, it becomes an atomic size region, and control of film formation becomes difficult.

An annealing apparatus according to the present invention is provided with a laser light source, an imaging optical system and a phase shifter provided on an optical axis of laser light from the laser light source, and an imaging position of the imaging optical system. A stage that can move in an X direction, a Y direction, and a Z direction that supports a target substrate on which an irradiated surface to be irradiated with light is annealed; and a beam profiler that monitors a light intensity distribution of laser light. An annealing device,
The beam profiler is
A wavelength conversion member containing trisodium 8-hydroxy-1,3,6-pyrenetrisulfonate having a desired spatial resolution for converting the laser light into visible light and displaying a light intensity distribution image of visible light When,
An magnifying optical system having an imaging device that captures a visible light image displayed on the wavelength conversion member;
A height sensor for detecting a height position of the wavelength conversion member;
The wavelength conversion member is aligned and controlled so that the measurement result of the height sensor is at a pre-stored height position, and the energy amount of laser light from the laser light source does not deteriorate or evaporate. Controlling so that the laser beam selected for the amount of energy is emitted from the laser light source, and the light intensity distribution of the laser beam that should first anneal the substrate to be processed is displayed on the wavelength conversion member. An intensity distribution image is captured by the imaging device, the light intensity of the laser light and the light intensity distribution image are detected, the detection result is set and stored as a target value in advance, and the light intensity captured by the imaging device height position of the wavelength conversion member as distribution image and intensity matches the light intensity distribution image and intensity of the target value stored in advance Control is possible, and to store the height position of the wavelength conversion member, and is retracted through the wavelength conversion member, moving the target substrate in position, calling the target value that has been said memory, said A computer that controls to irradiate the substrate with laser light having a light intensity and a light intensity distribution of an amount of energy for annealing the substrate to be processed corresponding to the target value from a laser light source. It is characterized by that.
The crystallization apparatus according to the present invention includes a laser light source, a phase shifter for forming a beam profile in which light intensity is minimized in a phase shift unit provided on an optical axis of laser light from the laser light source, and the laser An imaging optical system provided on the optical axis of the laser beam from the light source, and a laser beam having a beam profile provided at the imaging position of the imaging optical system and having a light intensity at the phase shift unit is minimized. A stage that can be moved in the X, Y, and Z directions to support a substrate to be processed including an amorphous semiconductor layer to be irradiated, a beam profiler that monitors the light intensity distribution of the laser beam, A crystallization apparatus comprising:
The beam profiler is
Trisodium 8-hydroxy-1 having a desired spatial resolution in order to display a light intensity distribution image of visible light by converting laser light having a beam profile with a minimum light intensity in the phase shift unit into visible light. , 3,6-pyrene trisulfonate-containing wavelength conversion member;
An magnifying optical system having an imaging device that captures a visible light image of a beam profile in which the light intensity is minimized in the phase shift unit displayed on the wavelength conversion member;
A height sensor for detecting a height position of the wavelength conversion member;
After the wavelength conversion member is aligned and controlled so that the measurement result of the height sensor is at a pre-stored height position, the energy by which the wavelength conversion member does not deteriorate or evaporate the energy amount of the laser light from the laser light source The laser light source selected in quantity is controlled to be emitted from the laser light source, and the light intensity distribution of the laser light to be annealed on the substrate to be processed first is displayed on the wavelength conversion member. The distribution image is imaged by the imaging device, the light intensity of the laser light and the light intensity distribution image are detected, the detection result is set and stored in advance as a target value, and the phase shift imaged by the imaging device Light intensity distribution image of the beam profile that minimizes the light intensity in the part and the light intensity distribution of the target value in which the intensity is stored in advance And controlling the height position of the wavelength conversion member to coincide with the intensity, storing the height position of the wavelength conversion member, and retracting the wavelength conversion member, and the substrate to be processed at that position. , The stored target value is recalled, and the laser beam having the light intensity and light intensity distribution of the amount of energy for annealing the target substrate corresponding to the target value from the laser light source And a computer that performs control to irradiate the light.

The invisible light to be detected may be pulsed light or continuous light. The pulse laser beam in the ultraviolet region is, for example, any one of krypton fluorine (KrF), argon fluorine (ArF), xenon fluorine (XeF), krypton chlorine (KrCl), argon chlorine (ArCl), and xenon chlorine (XeCl). 1 excimer laser light may be used, and pulse laser light in the infrared region may be Q-switched Nd: YAG laser light (fundamental wave), Q-switched Nd: YVO ₄ laser light (fundamental wave), etc. Also good. Alternatively, the CW (Continuous Wave) laser light in the ultraviolet region may be Nd: YAG laser light (third harmonic, fourth harmonic), Q switch Nd: YVO ₄ laser light (third harmonic, fourth harmonic), or the like. The CW laser light in the infrared light region may be CO ₂ laser light, Nd: YAG laser light (fundamental wave), Nd: YVO ₄ laser light (fundamental wave), or the like. Furthermore, i-line (wavelength 365 nm) and g-line (wavelength 436 nm) used in an exposure apparatus (stepper) in a photolithography process can be set as a detection target.

  As a means for capturing or observing the light intensity distribution image, a CCD element, an imaging tube, or the like is used. The analog signal observed by the observation means corresponds to the light intensity distribution of visible light including light intensity information and two-dimensional position information (coordinate information on the XY plane) by an analog-digital converter (AD converter). It is converted into a digital signal (imaging data) and output to an analysis means (for example, a personal computer). As another method not using AD conversion, the analog signal observed by the observation means is directly output as a voltage value (video signal or the like) corresponding to the light intensity information (two-dimensional image). The obtained two-dimensional image is processed as a voltage waveform using an amplifier, and an enlarged image of the light intensity distribution of visible light is displayed on the screen of the display device.

  In the present specification, the “two-dimensional image” refers to an analog data image including light intensity information and two-dimensional position information on a surface on which the wavelength-converted visible light is projected.

  In this specification, “Q switch” means that the resonator Q value is kept low while the excitation energy is accumulated in the laser medium to increase the number of inversion distributions, the laser oscillation is suppressed, and the inversion distribution is A switching element that has the function of instantaneously increasing the Q value when it becomes high enough to rapidly convert the inverted distribution accumulated energy into photon energy and oscillate high peak / short pulse light. Refers to a switching element that converts a continuous wave laser into a pulsed laser. In this specification, “Q-switched laser” refers to a laser that is oscillated by lowering the Q value until ion population inversion is established and switching to a higher value immediately before instability occurs. Say. To change the Q factor, use a mechanical Q-switch method that rotates one of the mirrors constituting the resonator, a method that uses light polarization by an acousto-optic device, or a change in polarization state by an electro-optic device. Any of the methods can be used.

In this specification, the “beam profiler” refers to a light intensity distribution monitoring device having a spatial resolution of 5 μm or less. “Light intensity distribution (beam profile)” refers to a two-dimensional distribution of invisible light intensity incident on an image plane to be detected. “Light intensity distribution” refers to the distribution of light intensity (brightness) on the detection surface of irradiation light (illumination light).

  In this specification, “laser fluence” is a scale representing the energy density of a laser at a certain position, which is obtained by integrating the amount of energy per unit area over time, specifically measured in a light source or an irradiation region. This means the average intensity of the laser beam. “Average laser fluence” refers to laser fluence that is uniformized within a certain processing area. The “wavelength conversion member” refers to a member that converts invisible light into visible light.

  In this specification, “spatial resolution” refers to the half-value width of the slope of the imaging data signal waveform in the transition region (region R shown in FIG. 14) where the white region transitions to the black region. Here, the “white region” refers to a region where a bright level image including a dark level appears clearly. The “black area” means an area having only a dark level. The “transition region” refers to a region where a bright level image including a dark level appears unclearly.

  In this specification, “phase shifter” refers to a spatial intensity modulation optical element for modulating the phase of light, and is distinguished from a phase shift mask used in an exposure step of a photolithography process. . The phase shifter is formed by, for example, forming a step on a quartz base material by etching.

  In the present specification, the “homogenizer” refers to an optical element that divides incident light into a plurality of pieces and converges the divided lights to make the light intensity uniform on a specific surface. In addition, the “homogenized surface” refers to a specific surface on which light passing through the homogenizer converges in the projection method.

  In the present specification, the “phase shifter surface” refers to a surface located between the bottom and the top of the light modulation portion (step difference of the phase shifter) of the spatial intensity modulation optical element. The phase shifter surface is preferably coincident with the homogenized surface (completely overlapped), but it is not always necessary to coincide, and the phase shifter surface is intentionally shifted from the position of the homogenized surface by a predetermined distance along the optical axis. There may be cases.

  In this specification, the “image plane” refers to a plane on which light passing through the imaging optical system of the proximity annealing apparatus converges.

  In this specification, the “primary image plane” refers to a plane on which light that has passed through the primary imaging optical system (homogenizer, condenser lens, mask, etc.) of the projection annealing apparatus converges to form an image. This primary image plane refers to the phase shifter plane and / or the homogenized plane when coincident with the phase shifter plane and / or the homogenized plane (complete overlap). It also includes a case where the primary image plane is intentionally shifted from the position of the phase shifter plane and / or the homogenized plane by a predetermined distance along the optical axis.

  In the present specification, the “secondary image plane” refers to a plane on which light passing through a secondary imaging optical system (such as a reduction lens) of a projection annealing apparatus converges to form an image. In other words, the “secondary image plane” refers to a plane on which an image formed on the primary image plane is transferred to the substrate side. This secondary image plane indicates the incident plane when it coincides (completely overlaps) with the incident plane. Further, it includes a case where the secondary image plane is intentionally shifted from the position of the incident plane by a predetermined distance along the optical axis.

  In the present specification, “the height of the phase shifter” refers to the mutual distance (gap d1 in FIG. 3) from the exit surface of the phase shifter to the incident surface of the substrate on the stage in the proximity annealing apparatus. .

  In this specification, the “deviation amount d2” refers to the distance from the homogenized surface to the phase shifter surface in the projection type annealing apparatus. When the homogenized surface coincides with the phase shifter surface, the shift amount d2 becomes zero (see FIG. 10).

  In this specification, the “deviation amount d3” refers to the distance from the phase shifter surface to the primary image surface in the projection type annealing apparatus. When the primary image plane coincides with the phase shifter plane, the shift amount d3 becomes zero (see FIG. 10).

  In this specification, the “deviation d4” refers to the distance from the incident surface of the substrate to be processed or the wavelength conversion member to the secondary image plane in the projection type annealing apparatus. When the secondary image plane coincides with the incident plane, the shift amount d4 becomes zero (see FIG. 10). The shift amount d3 and the shift amount d4 are directly proportional to the reduction ratio between the image on the primary image plane and the image on the secondary image plane.

  According to the present invention, the detection result of the light intensity distribution can be obtained in real time.

  In addition, the method of the present invention has an advantage that the detection result does not vary as compared with the conventional method in which measurement is performed using a material whose physical properties change (for example, resist, thin film amorphous silicon, etc.).

  Furthermore, since the invisible light is converted into visible light in the present invention, the following effects (i) to (iii) are recognized.

  (i) Since the magnifying optical system can be checked with a visible light image, it is easy to adjust the optical system such as an objective lens.

  (ii) Since the surface of the wavelength conversion member 63 is the surface to be detected, it is very easy to specify the image surface to be detected (the focus surface of the annealing apparatus).

  (iii) The optical system at the wavelength of the irradiation light is low in cost as compared with the invisible optical system component.

  The best mode for carrying out the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a block diagram schematically showing a light intensity distribution monitoring apparatus of the present invention. The light intensity distribution detector (beam profiler) 6 is configured to convert minute invisible light having a predetermined light intensity distribution into visible light having the light intensity distribution and to monitor the light. . The beam profiler 6 having this function includes, for example, a fluorescent plate 61 as a wavelength conversion member that converts invisible light into visible light in the optical path of a minute invisible light 50 having a predetermined light intensity distribution. This fluorescent plate 61 is obtained by attaching a fluorescent film 63 on one surface of a base material 62 made of a transparent material, for example, a transparent glass plate, for example, on the incident light side of invisible light 50. The fluorescent film 63 contains a fluorescent material for converting the invisible light 50 incident on one surface into visible light 50a.

  The monitoring of minute visible light having the light intensity distribution converted by the fluorescent film 63 is visible light directed toward the other surface side (back surface side) with respect to the incident surface of invisible light. Detection and monitoring of visible light toward the back side of the fluorescent film 63 is optimal. That is, if detection and monitoring of the visible light 50a generated on the incident surface of the fluorescent film 63 is performed from the same side as the side on which the invisible light 50 is incident, the detection data is distorted or a special optical system (dark field) It is difficult to obtain accurate results. For this reason, detection and monitoring of visible light are performed from the back side of the fluorescent film 63 (on the side opposite to the irradiation side of the invisible light 50). Visible light with a minute size having a light intensity distribution on the back surface of the fluorescent film 63 coincides with the optical axis 102 and can be accurately detected without causing distortion.

  A filter 64 is provided on the optical path converted into visible light on the back side of the fluorescent plate 61. In order to simplify the optical system, the filter 64 may be omitted by providing the base material 62 with the function of the filter 64. The filter 64 may be integrated with the fluorescent plate 61. At this time, component light that has not contributed to fluorescence, that is, invisible light 50 b transmitted through the fluorescent film 63 is absorbed by the base material 62.

  A magnifying optical system 60 is disposed in the optical path of the fluorescent plate 61 converted into visible light. The magnifying optical system 60 is for enlarging and capturing a minute optical image having a visible light intensity distribution formed on the fluorescent film 63. The surface of the fluorescent film 63 where the light intensity distribution of visible light is formed and the photosensitive surface of the charge coupled device (CCD) 69 are arranged in a conjugate relationship.

  The magnifying optical system 60 includes an objective lens 65, an optical cylinder 66, and a CCD 69 as shown in FIG. The objective lens 65 is attached to the tip of the optical tube 66 and is disposed so as to face the back surface of the fluorescent plate 61 through the filter 64. The objective lens 65 can be changed in size in which a minute light intensity distribution can be imaged in combination with another auxiliary lens (not shown), for example, in the range of magnification from 2 times to 2000 times. In this case, a specific magnification (for example, 150 times) within a range of 100 to 200 times is used. The field of view of the magnifying optical system 60 is preferably 50 μm to 300 μm, for example, 100 μm. The end side of the optical tube 66 is optically connected to the CCD 69.

  The beam profiler optical axis 102A corresponding to the optical axis of the magnifying optical system 60 is aligned so as to be parallel to the laser optical axis 102 of the imaging optical system 32. The alignment between the magnifying optical system 60 and the imaging optical system 32 is performed using the beam profiler alignment mechanism 80 shown in FIG. 1 and the substrate stage 7 shown in FIG. When the installation space is narrow and the length of the beam profiler 6 is limited in the direction of the laser optical axis 102, the beam profiler optical axis 102A is bent 90 ° from vertical to horizontal using a reflecting mirror 67 as shown in FIG. Can do. If the optical axis 102A is bent by 90 °, there is an advantage that the vertical length of the beam profiler 6 is shortened and the apparatus is downsized. However, in this optical axis bending type apparatus, it is necessary to bend the optical cylinder 66 by 90 ° from the vertical to the horizontal, and it is necessary to support the horizontal portion of the optical cylinder 66 with an appropriate support member (not shown). In this case, the beam profiler alignment mechanism 80 can movably support the optical tube 66 via the support member.

  The charge coupled device (CCD) 69 is an imaging device for capturing an enlarged visible light image. The CCD 69 is connected to an output circuit via an analog-digital converter via a communication line to a computer 8 serving as a recording / analyzing device, and transmits an imaging signal (light intensity distribution waveform signal of visible light) to the computer 8. It has become. The substantial spatial resolution of the beam profiler 6 at this time is 0.4 μm or less.

  A filter 64 is provided between the fluorescent plate 61 and the CCD 69 so that the transmitted invisible light 50b is absorbed or reflected so that the light intensity distribution of the visible light 50a is imaged on the CCD 69. The filter 64 is, for example, a transparent glass substrate coated with a multilayer coating film such as a dielectric. Further, the fluorescent plate base material 62 can also have a characteristic of absorbing or reflecting the invisible light 50b.

  As shown in FIG. 1, the light intensity distribution (beam profile) of the invisible light 50 incident from the imaging optical system 32 (see FIG. 3) forms an image on the image plane of the wavelength conversion member 63 and the wavelength conversion member. 63 is converted into visible light 50a. Next, in the light intensity distribution of the converted visible light 50 a, the invisible light 50 b is absorbed or reflected by the base material 62, and the remaining invisible light 50 b is absorbed or reflected by the filter 64.

  By providing the filter 64 between the fluorescent plate 61 and the CCD 69, it is possible to avoid adverse effects due to the invisible light 50b, such as deterioration of the objective lens 65, damage to the CCD 69, and mixing of noise into the image signal of the CCD 69. .

  The light intensity distribution of the transmitted visible light 50a is magnified to a desired magnification by the objective lens 65 of the magnifying optical system and imaged on the CCD 69. The CCD 69 outputs a light intensity distribution signal corresponding to the light intensity as imaging data, and the computer 8 that receives this data performs image signal processing digitally (as imaging data) or analog (as a two-dimensional image), and displays the display device. The enlarged light intensity distribution (beam profile) is displayed on the screen 8a. Further, the computer 8 records and analyzes the light intensity / position information and the temporal change of the imaged signal (two-dimensional image).

  The invisible light 50 is light having an amount of energy having an appropriate sensitivity with which the fluorescent film 63 converts invisible light into visible light, and is light whose wavelength, intensity, size, and the like are appropriately selected. The invisible light 50 is an amount of light that the fluorescent film 63 has moderate sensitivity and is not burned by being heated. The invisible light 50 refers to invisible light having an energy amount necessary for processing, for example, crystallization of a substrate to be processed such as an amorphous semiconductor layer. The material of the fluorescent film 63 is selected depending on whether the light for processing the workpiece is ultraviolet light or infrared light.

  In the present embodiment, the example in which the fluorescent film 63 is arranged on the incident surface side of invisible light and the base material 62 is arranged on the back surface side has been described, but conversely, the base material 62 is arranged on the incident surface side. The fluorescent film 63 may be disposed on the back side. However, in such a reverse arrangement, a material that absorbs or blocks the invisible light 50b cannot be used for the base material 62. Therefore, it is an essential requirement to provide a filter 64 that transmits only visible light in the subsequent stage. .

[ Monitoring light intensity distribution by proximity method]
Next, an embodiment in which the light intensity distribution monitoring device (beam profiler) 6 is incorporated in a proximity type laser annealing device will be described with reference to FIGS.
As shown in FIG. 3, the laser annealing apparatus 10A has both a function as a crystallization apparatus and a function as an annealing apparatus. That is, the laser annealing apparatus 10A has both a function of a crystallization apparatus for melting the amorphous semiconductor layer 5c (shown in FIG. 3) of the substrate to be processed and a function of an annealing apparatus for heat-treating the substrate to be processed. . Here, an embodiment in which the apparatus 10A is used for crystallization will be described. The excimer laser annealing apparatus 10A includes an excimer laser light source 1 as an invisible light generator. This excimer laser annealing apparatus 10A is provided with the above-described light intensity distribution monitoring apparatus 6 in order to monitor and detect the light intensity distribution (beam profile) of excimer laser light that heats and melts the amorphous semiconductor layer 5c. is there. When the light intensity distribution (beam profile) of the excimer laser light incident on the amorphous semiconductor layer is monitored and detected by the light intensity distribution monitoring device 6 , the fluorescent film 63 is replaced at the position of the amorphous semiconductor layer 5c. Installed. The energy of excimer laser light for melting the amorphous semiconductor layer 5c is, for example, illumination light of 200 mJ / cm ² or more. Monitoring the light intensity distribution (beam profile), the energy amount when detection ^{is 10mJ / cm 2 ~30mJ / cm 2} . The amount of energy for monitoring and detecting the light intensity distribution (beam profile) is smaller than the amount of energy for melting the amorphous semiconductor layer because the fluorescent film that converts invisible light to visible light has moderate sensitivity. This is because the energy amount that does not burn out is selected. In this embodiment, the crystallization process has been described as a processing means using invisible light. However, if the processing energy is small and the amount of energy that the fluorescent film 63 does not burn out, the light intensity distribution when the invisible light to be processed is incident on the fluorescent film 63 can be obtained.

  The configuration of the excimer laser annealing apparatus 10A will be described in more detail. As shown in FIG. 3, the excimer laser annealing apparatus 10 </ b> A includes an attenuator 2 and a mirror 4 on the start end side of a laser light source 1 that outputs invisible light, for example, the laser optical axis 102 of an excimer laser. The image-forming optical system 32 and the phase shifter 31 are disposed in the substrate, and the substrate 5 to be processed is disposed at the focal position of the image-forming optical system 32. This apparatus 10A is a so-called proximity type, and the phase shifter 31A is disposed immediately before the incident light side of the substrate 5 to be processed. The phase shifter 31A is a spatial intensity modulation optical element that forms a light intensity distribution suitable for a desired process on the substrate 5 to be processed.

  The imaging optical system 32 is an optical system for reducing the illumination intensity of the invisible light from the light source 1 on the substrate 5 to be processed. The imaging optical system 32 is not limited to reduction, and may be equal or enlarged. The optimal embodiment in the crystallization process is reduced illumination, and the optimal embodiment in the annealing process is 1X illumination.

  The moving stage 7 is a stage that can move in the X direction, the Y direction, and the Z direction. On the moving stage 7, a beam profiler 6 as a light intensity distribution detector and a substrate 5 to be processed are arranged in parallel. The beam profiler 6 and the substrate 5 to be processed are moved in the X direction, the Y direction, and the Z direction by the movement of the moving stage 7 and are aligned with the laser optical axis 102. . The beam profiler 6 and the substrate 5 to be processed are provided, for example, by being replaced on the laser optical axis 102 from the light source 1 in the crystallization process and the light intensity distribution detection process.

  The moving stage 7 includes, for example, roughly three stages 71, 72, 73 as shown in FIG. That is, in the moving stage 7, for example, an X stage 71 is movably supported on a linear guide that moves in the X direction (not shown), and a Y stage 72 that moves in the Y direction is movably supported on the linear stage. A Z stage 73 that is moved in a movable manner is movably supported. Further, the fluorescent plate 61 and / or the substrate to be processed 5 are provided at predetermined positions on the Z stage 73. Further, the moving stage 7 may be additionally provided with a θ rotation stage (not shown) for rotating the Z stage drive mechanism 73 around the Z axis. Furthermore, the moving stage 7 has a heater 7a, and can heat the substrate 5 to be processed to a predetermined temperature (see FIG. 3).

  On the main body of the Z stage 73, a pair of left and right sliders 74a and 74b are provided so as to be slidably guided along a linear guide (not shown). The opposing surfaces of both sliders 74a and 74b are inclined upward. A lifting platform 76 is provided between the sliders 74a and 74b so as to be slidably guided along an upward inclined surface. That is, the lift 76 has a downwardly inclined surface that matches the upwardly inclined surface of the sliders 74a and 74b. On the lifting platform 76, both or one of the fluorescent plate 61 and the substrate 5 to be processed is placed.

  The sides of the sliders 74a and 74b are rotatably connected to one ends of the corresponding ball screws 75a and 75b, respectively. The other ends of the ball screws 75a and 75b are connected to a rotation drive shaft of an elevating drive mechanism 9 made of a high-precision electric motor such as a stepping motor or a servo motor. A height sensor 78 composed of a semiconductor laser and a CCD for detecting the amount of reflected light is provided so as to detect the height position of the upper surface of the lifting platform 76. When a height position detection signal is sent from the height sensor 78 to the controller 8, the controller 8 controls the operation of the elevating drive mechanism 9 to rotate the ball screws 75 a and 75 b to raise or lower the elevating platform 76. It is like that. As a result, the substrate 5 to be processed and the fluorescent plate 61 on the lifting platform 76 are aligned with respect to the imaging optical system 32 and the phase shifter 31A with high accuracy.

  As shown in FIG. 1, in the magnifying optical system 60 of the beam profiler 6, the beam profiler optical axis 102 </ b> A is aligned in parallel with the laser optical axis 102. The beam profiler 6 is provided on the beam profiler alignment mechanism 80. The beam profiler alignment mechanism 80 is on the moving stage 7 described above, but is independently driven in each of the X, Y, and Z directions. The beam profiler alignment mechanism 80 may be provided on the moving stage 7.

  In the beam profiler alignment mechanism 80, an X stage 81, a Y stage 82, and a Z stage 83 are stacked in order from the bottom. That is, in the beam profiler alignment mechanism 80, an X stage 81 is movably supported on a linear guide (not shown), a Y stage 82 is movably supported thereon, and a Z stage 83 is movably supported thereon. A beam profiler 6 is supported on the top. The fluorescent plate 61 and the substrate to be processed 5 are respectively supported by the moving stage 7. Each height is stored by the height sensor 78, and when the beam profiler 6 is moved to a position where the laser optical axis 102 and the beam profiler optical axis 102A coincide with each other, profile observation (imaging) is started.

  FIG. 3 shows a conceptual diagram of the optical system of the proximity type annealing apparatus. FIG. 3 is a configuration diagram for specifically explaining the configurations of a phase shifter 31A, an imaging optical system 32, and a substrate 5 to be processed. As shown in FIG. 3, the imaging optical system 32 includes a homogenizer 32a, a first condenser lens 32b, a second condenser lens 32c, a mask 32d, a telecentric type, which are sequentially arranged from the light source side along the laser optical axis 102. Reduction lens 32e and phase shifter 31A. The homogenizer 32a has a function of making the oscillation laser light from the light source 1 uniform. The first condenser lens 32b condenses the homogenized laser light from the homogenizer 32a and is arranged in a conjugate relationship with the second condenser lens 32c. A mask 32d is provided on the outgoing optical path of the second condenser lens 32c. The mask 32d blocks ineffective laser light. The reduction lens 32e has a function of reducing an image in a range of 1/1 to 1/20 times. The light that has passed through the reduction lens 32e is incident on the target substrate 5 from the surface of the insulating cap film 5d (the incident surface 36 of the target substrate) and converges on the image plane 37. The image surface 37 may or may not coincide with the incident surface 36. In a normal case, the image plane 37 is shifted by a desired distance from the incident plane 36 by adjusting the gap d1, and the image plane 37 is not coincident with the incident plane 36. The shift amount between the image plane 37 and the incident plane 36 is optimally adjusted according to the film thickness of the cap film 5d.

  The phase shifter 31A forms, for example, a beam profile having an inverted peak pattern in which the light intensity is minimized in the phase shift unit by shifting the phase of the light passing through the mask 32d, and the processed object is processed by the beam profile of the inverted peak pattern. For example, the position of the first solidified region (crystal nucleus) of the amorphous semiconductor film is controlled on the substrate 5, and the crystal is grown laterally therefrom (lateral growth; two-dimensional growth along the film surface). To provide a crystal grain having a large grain size at a designated position. At this time, a desired light intensity distribution (beam profile) is set based on the shape of the phase shifter 31A, the height of the phase shifter 31A (gap d1 in FIG. 3), the angular distribution of laser light, and the like. The personal computer 8 performs feedback control with high accuracy so that the gap d1 becomes a desired value. In the figure, reference numeral 34 denotes a phase shifter surface.

The width W of the reverse peak pattern in the two-dimensional light intensity distribution (two-dimensional beam profile) is proportional to the 1/2 power of the gap d1 between the phase shifter 31A and the fluorescent plate 61 (or the substrate 5 to be processed) (W = k).・ D ^1/2 ; k is a coefficient). The average light intensity (average laser fluence) of the laser beam 50 is detected separately using a power meter or the like.

  The fluorescent plate 61 is installed on the same plane or a parallel plane as the substrate 5 to be processed. When the fluorescent plate 61 is installed on a parallel plane, the moving stage 7 is moved up and down to detect the fluorescent plate 61 with the height sensor 78 so as to be the same height as the substrate 5 to be processed. Thereby, since the light intensity distribution (beam profile) of the laser beam on the substrate surface can be detected under the same conditions as in actual irradiation, the fluorescent plate 61 and the substrate to be processed 5 do not have to be on the same plane. . For example, the standby position of the fluorescent plate 61 is not limited to the same height level as the processing position of the substrate 5 to be processed, and may be above the processing position or below the processing position. The fluorescent plate 61 may be positioned optically equivalent to the surface of the substrate 5 to be processed.

  Imaging data (or observation data) received and imaged by the CCD 69 is input to a computer 8, which slices the imaging data along an arbitrary scanning line, and determines the intensity and light intensity of the laser light from the intensity distribution of the image signal. A distribution (beam profile) is output, and this output is used as a detection result.

  Then, the amount of operation is calculated by comparing the detected intensity with a preset target intensity, and the angle of the attenuator 2 is fed back by outputting an operation signal to the attenuator 2 so that the detected intensity becomes the target intensity. Adjust.

Further, the operation amount is calculated by comparing the detected light intensity distribution image, the light intensity distribution image of the preset target value, and the signal from the height sensor 78, and a signal corresponding to the operation amount is output to the moving stage 7. Then, the mechanism is feedback controlled so that the detected light intensity distribution image matches the light intensity distribution image of the target value . As a result, the gap d1 between the fluorescent plate 61 (or the substrate 5 to be processed) on the moving stage 7 side and the phase shifter 31A is determined.

  In this embodiment, an example in which the laser light intensity, the laser light distribution, and the gap d1 are adjusted by a feedback control method is described. However, the present invention is not limited to this, and the laser light intensity, All of the laser light distribution and the gap d1 are detected, the detection result is set as a target value, stored (recorded), and can be recalled and used when it becomes necessary to perform laser irradiation. Thereby, laser irradiation with high reproducibility can be realized, and crystallization of the TFT channel portion can be performed stably.

  Next, a crystallization method using a laser annealing apparatus will be described in detail with reference to FIG.

The laser annealing apparatus 10A applies intensity and light intensity distribution (beam profile) to a substrate 5a in which a base protective layer 5b, an amorphous silicon film 5c, and a cap layer 5d are sequentially laminated in advance on a substrate 5a such as a glass substrate. ) Is irradiated with the modulated laser beam 50 to crystallize. The object of crystallization is the amorphous silicon film 5c. The base protective layer 5b and the cap layer 5d are each made of an SiO ₂ insulating film.

  A rectangular laser beam having a wavelength of 248 nm is emitted from the KrF excimer laser oscillation device 1 serving as a light source. First, the laser fluence of the laser light 50 is optically modulated by adjusting the angle of the dielectric multilayer coating filter in the attenuator 2. Next, it reaches the imaging optical system 32 via the mirror 4 and is divided into divergent beams by a homogenizer 32a composed of two pairs of small lens pairs (x direction and y direction, respectively). Note that the pulse duration of one shot is 30 nanoseconds. Each central-axis light beam of the divided beam is collected at the center of the mask 32d by the condenser lens 32b (convex lens # 1).

  Further, since each beam is slightly divergent, the entire surface of the mask 32d is illuminated. Since all the light beam groups that have exited the divided minute emission areas irradiate all points on the mask 32d, the light intensity of the mask 32d is not limited even if the light intensity on the laser emission surface is uneven. It becomes uniform. “In-plane unevenness” refers to non-uniformity of the energy distribution that varies spatially.

  The central ray of the light ray group that passes through each region of the mask 32d, that is, the divergent ray group that has passed through the lens pair in the central portion of the homogenizer 32a is converted into a parallel ray by the convex lens 32c near the mask surface, and then telecentric reduction. Through the lens 32e, the substrate 5 to be processed placed on the moving stage 7 provided with the heater 7a is irradiated vertically.

  Since the movable stage 7 can be adjusted in position in the X, Y, and Z directions, a large area can be crystallized by repeating the annealing while shifting the irradiation region. Further, the light beam group that has passed through the same portion of the mask 32d converges to one point on the substrate surface. That is, a reduced image of the mask 32d is formed on the substrate surface with uniform light intensity. XY represents the X axis and Y axis of the horizontal plane, and Z represents a vertical axis extending in a direction perpendicular to the horizontal plane.

  A group of light beams that illuminate an arbitrary point on the substrate surface is made up of light beams that are split including the central light beam that passes through the laser optical axis 102. The angle formed by a certain light beam and the central light beam is a value determined by the geometric shape of the homogenizer 32a and the angle formed by the light beam and the central light beam on the mask 32d multiplied by the magnification of the telecentric lens 32e.

  The phase shifter 31A disposed close to the substrate to be processed 5 (or the fluorescent plate 61) within 500 μm has a predetermined step 31a, and causes Fresnel diffraction to occur independently at each of the divided light beams at the step 31a. Since these diffraction patterns are superimposed on the substrate surface, the light intensity distribution on the substrate surface includes not only the parameters of the phase shifter 31A (gap d1, phase difference θ) but also the amount of spread of the light rays incident on the phase shifter 31A. (Ε) and the coherence between light beams are complicatedly related.

  The laser beam that has passed through the phase shifter 31A forms an image on the cap film 5d of the substrate 5 to be processed. The laser light incident on the cap film 5d passes through the cap film 5d and enters the amorphous Si film 5c, and heats the amorphous Si film 5c. The heated amorphous Si film 5c is melted. The melted amorphous Si film 5c is naturally cooled, solidified, and crystallized.

Next, examples will be described.
(Example 1)
In Example 1, using the apparatus of the present invention, the average film thickness of the wavelength conversion member for detecting the light intensity distribution of the excimer laser light (wavelength 248 nm) oscillated from the KrF excimer laser annealing apparatus was 2 μm. The average fluence of the laser beam was 15 mJ / cm ² , and the irradiation area 10 was 1 mm × 1 mm square.

Pyranine (C ₁₆ H ₇ Na ₃ O ₁₀ S ₃ ) was used as the fluorescent material constituting the wavelength conversion member. The emission intensity (fluorescence intensity) of pyranin is highly dependent on the fluence of excimer laser light in the energy range from low level to medium level. For example, it has been found that the emission intensity of the pyranin phosphor increases in direct proportion to the laser fluence in the energy region where the fluence of incident laser light is 30 mJ / cm ² or less (see FIG. 14).

Next, the outline of the analysis procedure of the light intensity distribution will be described with reference to FIG.
FIG. 5A is a flowchart showing a procedure for analyzing the light intensity distribution, and FIG. 5B is a diagram showing signal waveforms during the analysis procedure.

  First, a preparation procedure before imaging will be described. In FIG. 3, the shutter is closed to block the laser beam 50 from entering the CCD 69. Although the phase shifter 31 is not inserted in the optical system, the fluorescent plate 61 having the wavelength conversion member 63 is disposed at the imaging position.

  In this way, the CCD 69 is picked up without an image, and black level image pickup data in the CCD output is sent to the personal computer 8. The black level imaging data is, for example, like a signal waveform 14x shown in FIG. 5B, and has a DC component with a low intensity level. The personal computer 8 stores black level imaging data (dark level image) corresponding to the signal waveform 14x as preliminary data before imaging (step F1).

Next, the light source 1 is set so that the laser light 50 emitted from the light source 1 has a provisional normalized intensity (for example, 15 mJ / cm ² ) (step F2). This provisional normalized strength is appropriately selected empirically within a range where the fluorescent material constituting the wavelength conversion member does not deteriorate or evaporate. The normalized intensity of the interim in the present embodiment has been set to 15 mJ / cm ^2, which may be a 20 mJ / cm ^2.

  The shutter of the CCD 69 is opened, laser light 50 having a provisionally normalized intensity is incident on the CCD 69, and white level imaging data in the CCD output is sent to the personal computer 8. The white level imaging data is, for example, a signal waveform 14y shown in FIG. 5B, and has a DC component with a high intensity level. The personal computer 8 stores white level imaging data (bright level image including a dark level) corresponding to the signal waveform 14y (step F3).

  Next, the personal computer 8 recalls the black level imaging data (corresponding to the waveform 14x) stored in Step F1 from the memory, and the light level image data (waveform 14y) including the dark level stored in Step F3. 2) is read from the memory, and the waveform 14x is subtracted from the waveform 14y to obtain the waveform 14z (= 14y-14x) shown in FIG. 5B (step F4), thereby obtaining the light level image data. Data corresponding to the waveform 14z is stored in the personal computer 8.

  The above is the preparation flow before imaging.

Next, an actual imaging procedure will be described.
The phase shifter 31B is inserted into a predetermined position of the optical system and aligned with other members (step F5). Next, the reverse peak pattern waveform 14a shown in FIG. 5B is input to the personal computer 8 as imaging data (light intensity distribution) of CCD output at the time of actual imaging (step F6). The personal computer 8 recalls the black level imaging data stored in step F1 from the memory, subtracts the black level imaging data (corresponding to the waveform 14x) from the input imaging data (corresponding to the waveform 14a), and FIG. Waveform 14b (= 14a-14x) shown in FIG. By removing the black level component in this way, the zero point adjustment of the imaging data of the CCD output is performed (step F7). In this zero point adjustment step F7, the zero point adjusted waveform 14b obtained by integrating and averaging all the light intensities in the measurement visual field is output.

  Next, the zero-point adjusted waveform 14b is normalized by the personal computer 8 (step F8). In the normalization step F8, the personal computer 8 retrieves data corresponding to the waveform 14z obtained in the preparation flow before imaging from the memory, sets the average value of the waveform 14b adjusted to zero to 1, and divides this by the waveform 14z. The normalized waveform 14c (= 14b / 14z) is output. The waveform 14c shown at the end of FIG. 5B corresponds to the output light intensity distribution, and actual laser irradiation is performed using this as comparison data.

  Next, referring to FIG. 6, an embodiment of a method for detecting the light intensity distribution by the apparatus of the present invention and actually crystallizing the amorphous silicon thin film by the ELA method based on the detection result will be specifically described. explain. The parts described in FIGS. 1 to 5 are given the same reference numerals, and the detailed description thereof will be omitted because it is duplicated.

First, prior to the crystallization step, the light intensity distribution of the invisible light for crystallization is confirmed by the following process. The average laser fluence of the attenuator 2 was adjusted to a value (10 mJ / cm ² ) necessary for imaging or observing the beam profile (step S1). Next, after the substrate 5 to be processed was retracted to a predetermined position, the profiler 6 was entered and placed in the irradiation field (step S2). Using the alignment mechanism 7 and the beam profiler alignment mechanism 80, the beam profiler optical axis 102A was optically aligned with the laser optical axis 102 on the light source side (step S3). The waveform data (target value of the light intensity distribution) obtained in the above steps F1 to F8 is called from the personal computer 8, and the gap d1 that is theoretically estimated is calculated by analyzing the image (step S4). Next, using the moving mechanism of the phase shifter 31A, the substrate stage 7 and the height sensor 78, the fluorescent plate 61 is aligned with respect to the phase shifter 31A, and the gap d1 is adjusted to a target value obtained by calculation (step S5). The laser beam was irradiated and the light intensity and light intensity distribution (beam profile) were detected (step S6). Details of step S6 are shown in steps F1 to F8 in FIG. The detected light intensity distribution is collated with a predetermined light intensity distribution (step S7), and if they are different, the gap d1 is finely adjusted until they match (step S71). If they match, the gap d1 at this time is stored, and the beam profiler 6 is withdrawn from the irradiation field (step S8). Next, the substrate stage 7 was made to enter the irradiation field (step S9). The incident surface of the substrate 5 to be processed was moved to a position where annealing was desired, and aligned with the laser optical axis 102 on the light source side (step S10). Next, using the substrate stage 7, the gap d1 between the substrate 5 to be processed and the phase shifter 31A was adjusted to the value stored in step S7 (step S11).

  Next, the angle of the attenuator 2 was adjusted so that the detected intensity and the light intensity distribution coincided with a preset target. That is, if the waveform when the average laser fluence is 1000 mJ / cm 2 is suitable, the angle of the attenuator 2 is adjusted to such a value (step S12). Next, the amorphous silicon film 5c was annealed by irradiating the processing target substrate 5 with laser light having the set intensity and light intensity distribution (step S13).

  Since the moving stage 7 can be moved step by step within the XY plane and changed in position, the large area can be crystallized by repeating annealing by shifting the irradiation region. Yes (step S14). In addition, XY shows the X-axis and Y-axis of a horizontal surface, Z shows the axis | shaft extended in the direction perpendicular | vertical to a horizontal surface. It was determined whether or not the previous irradiation region was the last (step S15). If the determination result in step S15 is NO, annealing in step S13 was performed. If the determination result of step S15 is YES, the substrate stage is returned to the home position, and the crystallization process is terminated.

  The above detection, alignment, and irradiation are repeated to form crystal regions in which the TFTs have different sizes but the average number of crystal grain boundaries across the current direction in the channel region is constant. Note that the three operations of detection, alignment, and irradiation need not be repeated every time. First, all the detections are performed, and the detection results are stored (recorded). If necessary, the operation amount required for alignment is obtained, and then alignment and irradiation are performed for each crystal region. May be performed in parallel.

  In the above embodiment, an example in which the light intensity distribution detection and confirmation process is performed once before the crystallization process is described. However, the light intensity distribution detection and confirmation process is performed first, The entire surface of the substrate to be processed 5 may be crystallized, or it is desirable to perform it once every several crystallization regions, once every several tens, hundreds or thousands. The more the steps of detecting and confirming the light intensity distribution, the more uniform crystallization can be performed.

  In the above embodiment, the so-called proximity method is described in which the phase shifter is brought close to a predetermined position with respect to the substrate to irradiate a laser beam having a predetermined fluence, but this is a projection method (a laser light source in which the phase shifter is separated from the substrate). You may make it use in combination with the projection system arrange | positioned in the side.

[ Monitoring of light intensity distribution by projection method]
Next, an embodiment in which the light intensity distribution monitoring device (beam profiler) 6 is incorporated in a projection type laser annealing device will be described with reference to FIGS. In addition, description of the part which this embodiment overlaps with said embodiment is abbreviate | omitted.

  The laser annealing apparatus 10B shown in FIG. 7 includes a first imaging optical system 32A, a phase shifter 31B, a mirror 4, and a second imaging optical system 32B arranged along the optical axis 102 in order from the laser light source 1 side. It has. This apparatus 10B is a so-called projection type laser annealing apparatus in which a phase shifter 31B is provided between the first imaging optical system 32A and the second imaging optical system 32B, and excimer laser light 50 is supplied to the first coupling optical system 32B. Uniformity by the image optical system 32A, light intensity modulation of the homogenized light by the phase shifter 31B, and further reduction of the light intensity modulated light to a predetermined magnification by the second imaging optical system 32B, the wavelength conversion member 6 or the substrate to be processed 5 is projected onto the incident surface 36.

Next, the alignment mechanism 90 of the phase shifter 31B in the projection type laser annealing apparatus will be described.
FIG. 8 is a plan view showing the phase shifter holder as viewed from above. The holder 90 includes an outer ring 91 and an inner ring 92 arranged concentrically and connected to each other. The holder outer ring 91 is movably supported by an X drive mechanism 93, a Y drive mechanism 94, and a Z drive mechanism 96, and is finely moved in the X, Y, and Z directions. The holder inner ring 92 has a plurality of stoppers for locking the phase shifter 31B (not shown). The phase shifter 31B is fitted into the inner ring 92, and the periphery thereof is locked by a stopper. The holder inner ring 92 is movably held by the holder outer ring 91, and the rotation angle θ of the inner ring 92 in the XY plane can be finely adjusted by a mechanism (not shown).

  FIG. 9 is a side sectional view of the phase shifter holder. The angle φ formed by the optical axis 102 and the normal line of the surface of the phase shifter 31B can be adjusted by a mechanism not shown. By controlling the amount of movement of the cylinder rod of the Z drive mechanism 96, the image plane of the phase shifter 31B can be controlled. In this way, the phase shifter 31B is aligned with other members of the imaging optical system 32 with high accuracy.

Next, the optical system will be described in detail with reference to FIG.
The first imaging optical system 32A includes a homogenizer 32a, a first condenser lens 32b, a second condenser lens 32c, and a mask 32d. These optical components 32a, 32b, 32c, and 32d are substantially the same as the optical components of the imaging optical system 32 of the apparatus 10A described above.

  The first and second imaging optical systems 32A and 32B are fixedly supported by frames (not shown). On the other hand, the phase shifter 31B is movably supported by an alignment mechanism 90 shown in FIGS. The phase shifter 31B is arranged in the vicinity of the opening of the mask 32d while being positioned by the alignment mechanism 90 so that the amount of deviation d2 between the homogenizing surface 33 and the phase shifter surface 34 becomes a predetermined value. The standard deviation amount d2 is zero (coincidence (complete overlap) between the homogenized surface 33 and the phase shifter surface 34). The following explanation will be made under these conditions unless otherwise specified. The traveling direction of light is positive, and the opposite direction is negative.

  The light that has passed through the first imaging optical system 32A passes through the primary image plane 35 and enters the second imaging optical system 32B. The second imaging optical system 32B includes a telecentric reduction lens 32e, and forms a two-dimensional image of the laser light whose light intensity is modulated by the phase shifter 31B on the secondary image plane 37. The secondary image plane 37 is shifted from the incident plane 36 in the direction of the optical axis 102 by a shift amount d4. The shift amount d4 is adjusted to a desired value by raising and lowering the substrate stage 7. Since the image on the secondary image plane 37 is the image on the primary image plane 35 transferred at a predetermined reduction magnification, the deviation amount d4 is a value obtained by multiplying the deviation amount d3 by the square of the predetermined reduction magnification N (N × N) (both are in direct proportion). It is assumed that the primary image surface 35 coincides with the phase shifter surface 34 (completely overlap) when the displacement amount d4 is zero (the displacement amount d2 is zero). For example, the secondary image plane 37 when the shift amount d4 is +0.1 mm corresponds to the primary image plane 35 where the shift amount d2 is +0.1 mm / (N × N) mm. However, in this state, the primary image plane 35 can be projected onto the secondary image plane 37 by changing the shift amount d4 while the phase shifter moving mechanism 90 is fixed. Note that the signal obtained from the height sensor 78 is set to zero at the height (z value) of the substrate stage 7 at which the shift amount d4 is zero.

  The substrate stage 7 includes a height sensor 78, alignment mechanisms 71 to 76, and an elevating mechanism 9. The substrate stage 7 is positioned by the alignment mechanisms 71 to 76 and the lifting mechanism 9 so that the amount of deviation d4 between the secondary image surface 37 and the incident surface 36 of the wavelength conversion member 61 (or the substrate 5 to be processed) becomes a predetermined value. Has been. This positioning is performed by the personal computer 8. That is, when the personal computer 8 receives the height position signal of the lifting platform 76 of the substrate stage 7 detected by the height sensor 78, the personal computer 8 controls the operation of the lifting mechanism 9 so that the shift amount d4 becomes a predetermined value based on the signal. In this case, the standard deviation d4 is zero, but it may be, for example, 5 to 100 μm. The light that has passed through the reduction lens 32 </ b> B converges on the target substrate 5 placed on the secondary image plane 37.

Next, referring to FIG. 11, an embodiment of a method for detecting the light intensity distribution by the apparatus of the present invention and actually crystallizing the amorphous silicon thin film by the ELA method based on the detection result will be specifically described. explain.
First, prior to the crystallization step, the light intensity distribution of the invisible light for crystallization is confirmed by the following process. The average laser fluence of the attenuator 2 was adjusted to a value (10 mJ / cm ² ) necessary for imaging or observing the beam profile (step K1). Next, after the substrate 5 to be processed was retracted to a predetermined position, the profiler 6 was entered and placed in the irradiation field (step K2). The beam profiler optical axis 102A was optically aligned with the laser optical axis 102 on the light source side using the alignment mechanism 7 and the beam profiler alignment mechanism 80 (step K3). Waveform data (target value) is called from the personal computer 8 and the image is analyzed to calculate a theoretically estimated shift amount d4 (step K4). This waveform data is storage data of the light intensity distribution obtained by the above-described preparation flows F1 to F8 of FIG. 5, and is a target value for the light intensity distribution.

  Next, the shift amount d4 was adjusted to the target value obtained by calculation using the substrate stage 7 and the height sensor 78 (step K5). Laser light was irradiated to detect the light intensity and light intensity distribution (beam profile) (step K6). The detailed content of the process K6 is shown in the preparation flow of FIG. The detected light intensity distribution is collated with a predetermined light intensity distribution (step K7), and if they are different, the shift amount d4 is finely adjusted until they match (step K71). If they match, the shift amount d4 at this time is stored, and the beam profiler 6 is withdrawn from the irradiation field (step K8). Next, the substrate stage 7 was made to enter the irradiation field (step K9). The incident surface of the substrate 5 to be processed was moved to a position where it was desired to anneal, and aligned with the laser optical axis 102 on the light source side (step K10). Next, the shift amount d4 of the substrate 5 to be processed was adjusted to the value stored in step K7 using the substrate stage 7 (step K11). Next, the angle of the attenuator 2 was adjusted so that the detected intensity and the light intensity distribution coincided with a preset target. That is, if the waveform when the average laser fluence is 1000 mJ / cm 2 is suitable, the angle of the attenuator 2 is adjusted to such a value (step K12). And the laser beam of the intensity | strength set by process K12 and light intensity distribution was irradiated. (Step K13).

  Since the moving stage 7 can be moved step by step within the XY plane and changed in position, the large area can be crystallized by repeating annealing by shifting the irradiation region. Yes (step K14). In addition, XY shows the X-axis and Y-axis of a horizontal surface, Z shows the axis | shaft extended in the direction perpendicular | vertical to a horizontal surface. It was determined whether or not the previous irradiation region was the last (step K15). If the determination result in step K15 is NO, annealing in step K13 was performed. If the determination result in step K15 is YES, the substrate stage is returned to the home position, and the crystallization process is terminated.

(Verification test)
Next, with reference to FIG. 12 and FIG. 13, the characteristics of the modulated laser beam and its real image will be described from the actual measurement result of the light intensity distribution on the sample surface.

  FIG. 12A shows a one-dimensional normalized Fresnel diffraction pattern by an isolated phase shifter (optical path difference δ is 180 °) when parallel light is used. The distance between the phase shifter and the profiler (equivalent to the phase shifter / substrate gap d1) was 110 μm. FIG. 12B is a characteristic diagram showing a one-dimensional light intensity distribution of the diffraction pattern of FIG. The characteristic line A (thin line) in the figure shows the computer simulation result, and the characteristic line B (thick line) shows the actual measurement result on the beam profiler fluorescent screen. As is clear from these measurement results, good agreement with the theoretical results was obtained, including higher-order vibrations. In particular, the minimum intensity of almost zero indicates that excimer laser light has strong self-interference. The spatial resolution of the beam profiler is preferably about an order of magnitude smaller than the crystal grain size to be manufactured. In the detection examples of FIGS. 12A and 12B, the resolution was 0.4 μm.

  FIG. 13 shows a two-dimensional normalized Fresnel diffraction image (two-dimensional data of a beam profile) by an in-plane cross-coupled phase shifter. This figure shows the real image of the laser fluence that appeared on the beam profiler phosphor screen. The gap d1 was 30 μm and the phase difference was 180 °. The square lattice surrounded by the thick line in the figure has a side length of 5 μm. In addition to the grid-like main pattern (thick line), an internal fine two-dimensional pattern (thin line) can also be captured, and it has been demonstrated that this profiler is also effective for evaluating two-dimensional patterns.

FIG. 14 shows the fluence of excimer laser light of pyranin, with the horizontal axis representing the excimer laser light irradiation intensity (unit: mJ / cm ² ) and the vertical axis representing the fluorescence intensity of pyranine irradiated with laser light (unit: relative value). It is a characteristic diagram which shows the result investigated about the emitted light intensity dependence with respect to. According to this figure, it has been found that the emission intensity of the pyranin fluorescent substance increases linearly until the energy amount of the incident laser light is up to 30 mJ / cm ² .

  FIG. 15 shows the result of evaluating the spatial resolution of the light intensity distribution detection apparatus of the present invention using the metal mask with the horizontal axis as the edge position (μm) of the metal mask and the vertical axis as the fluorescence intensity (relative value). It is a characteristic diagram. For the measurement of spatial resolution, a wavelength conversion member in which an organic fluorescent material (pyranin) was applied to a transparent substrate was used. The high part of the characteristic line C in the figure corresponds to the white area (where there is no metal; the light level area including the dark level), and the low part corresponds to the black area (where the metal is present; only the dark level area). . A symbol R in the figure indicates a transition region that changes from a white region to a black region. That is, in the drawing, the left side of the transition region R indicates a region without metal, and the right side of the transition region R indicates a region with metal.

  If this waveform C is used, the spatial resolution can be evaluated because it is a one-dimensional graph showing a state of changing from a white region to a black region in an image image in the spatial resolution evaluation test. As is clear from the figure, in the transition region R, the half-value width (that is, resolution) of the inclination is about 0.4 μm. As a result of MTF (Modulation Transfer Function) evaluation on this image, it was found that the image has a resolution of 2500 lines / mm at a low-to-high contrast ratio of 10%.

  The properties of excimer laser light were extracted by high resolution beam profiler. As a result, the light intensity distribution on the sample surface can be designed. Furthermore, by evaluating various critical light intensities and combining these results, an optical system for growing large crystal grains with a high filling rate was designed. This effectiveness was confirmed by the above-described demonstration test.

(Example 2)
As Example 2, the light intensity distribution of infrared laser light (wavelength 1064 nm) pulse-oscillated from a Q-switched YAG laser device was detected using the apparatus of the present invention.

As the fluorescent substance to be included in the wavelength conversion member, the product name of YAGLASS (Yaglass) Sumita Optical Glass Co., Ltd. was used. The average film thickness of the wavelength conversion member was 2 μm. As the light intensity modulation element, a substrate in which a part of Si was shielded with Cr metal was used. The average fluence of the laser beam was 30 mJ / cm ² and the beam diameter was 1 mm × 1 mm square.

  From the detection result of the light intensity distribution of the Q-switched YAG laser beam by the apparatus of the present invention, a high resolution image of 10 μm could be confirmed.

(Example 3)
As Example 3, the light intensity distribution of ultraviolet rays (wavelength 365 nm) irradiated from the i-line lamp of the exposure apparatus was detected using the apparatus of the present invention.

A substrate coated with nano-particle CdSe was used as the fluorescent material included in the wavelength conversion member. The average film thickness of the wavelength conversion member was 0.5 μm. A light intensity modulation element made of synthetic quartz and partially shielded with Cr metal was used. The average output of the lamp light was 30 mW / cm ² and the beam diameter was 1 mm × 1 mm square.

  A high resolution image of 0.4 μm could be confirmed from the detection result of the light intensity distribution of ultraviolet light by the apparatus of the present invention.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  The present invention includes only an excimer laser annealing technique (ELA method) for crystallizing or activating impurities in a semiconductor thin film that becomes a channel region of a TFT used in a circuit of a display device such as a liquid crystal display device or an electroluminescence display device. In addition, Q-switched YAG laser or copper vapor laser that oscillates laser light in the infrared wavelength region, or excimer lamps, i-line lamps, g-line lamps, Xe lamps, etc. of semiconductor manufacturing equipment that emits light in the ultraviolet wavelength region The present invention can be used in various technical fields such as a technique for measuring a light intensity distribution of a certain size.

1 is a configuration block diagram schematically showing a light intensity distribution monitoring apparatus of the present invention. The schematic block diagram which shows typically the example which combined the light intensity distribution monitoring apparatus of this invention with the proximity type | mold laser annealing apparatus. The block diagram which shows an example of the imaging optical system of a proximity type laser annealing apparatus. The block diagram which shows typically the positioning mechanism of a wavelength conversion member. (A) is a flowchart showing the analysis procedure of the light intensity distribution, (b) is a diagram showing the signal waveform during the analysis procedure. The flowchart which shows an example of the ELA method using the light intensity distribution monitoring method of this invention. The schematic block diagram which shows typically the example which combined the light intensity distribution monitoring apparatus of this invention with the projection type laser annealing apparatus. The top view which shows the positioning mechanism of a phase shifter. The expanded sectional view which shows a part of positioning mechanism of a phase shifter. FIG. 3 is a configuration block diagram showing an example of an imaging optical system of a projection type laser annealing apparatus. The flowchart which shows an example of the ELA method using the light intensity distribution monitoring method of this invention. (A) is the SEM image which shows the two-dimensional image in the beam profiler fluorescent screen of an isolated phase shifter, (b) is the one-dimensional light intensity distribution characteristic diagram. The SEM image which shows an example of the two-dimensional image in a laser irradiation area | region. The characteristic line figure which shows an example when the light intensity distribution of an excimer laser is measured using the light intensity distribution monitoring method of this invention. The characteristic diagram which shows the result investigated about the spatial resolution of the beam profiler which has the wavelength conversion member which apply | coated the organic fluorescent material.

Explanation of symbols

1 ... light source,
2 ... Attenuators 31A, 31B ... Phase shifters (spatial intensity modulation optical elements)
32 ... Imaging optical system 32A ... First imaging optical system 32B ... Second imaging optical system 32a ... Homogenizer (light intensity uniformizing optical element)
32b, 32c ... condenser lens 32d ... mask, 32e ... telecentric reduction lens 33 ... homogenized surface 34 ... phase shifter surface 35 ... primary image plane (image plane of the first imaging optical system)
36: Incident surface 37 of wavelength conversion member or substrate to be processed 37: Secondary image plane (imaging plane of second imaging optical system)
d1 ... gap from the phase shifter surface to the incident surface d2 ... deviation amount between the homogenized surface and the phase shifter surface d3 ... deviation amount between the primary image surface and the incident surface d4 ... deviation amount 5 between the secondary image surface and the incident surface ... Substrate to be processed, 5a ... substrate, 5b ... underlying protective layer 5c ... amorphous semiconductor layer (crystallization target film, amorphous silicon film)
5d: Cap layer 50: Invisible light (laser light)
50a ... Visible light 50b ... Invisible light 6 absorbed or reflected 6 ... Beam profiler ( light intensity distribution monitoring device )
60 ... Magnifying optical system 61 ... Fluorescent screen (wavelength conversion member)
62 ... Base 63 ... Fluorescent film (wavelength conversion member)
64 ... Filter 65 ... Objective lens 66 ... Optical cylinder 67 ... Mirror 68 ... Support 69 ... CCD (imaging means, image measuring means)
7 ... Moving stage ( XYZ stage, substrate stage, substrate alignment mechanism)
71 ... X stage 72 ... Y stage 73 ... Z stages 74a, 74b ... Sliders 75a, 75b ... Ball screw 76 ... Elevating platform 78 ... Height sensor (position detecting means)
8: Computer (analysis means, processing device)
8a ... Display device 80 ... Beam profiler alignment mechanism 81 ... X stage 82 ... Y stage 83 ... Z stage 9 ... Lifting mechanism 90 ... Alignment mechanism (positioning mechanism for phase shifter)
91 ... Holder outer ring 92 ... Holder inner ring, 92a ... Stopper 93 ... X drive mechanism, 94 ... Y drive mechanism 95a-95c ... Pivot, 96a ... Cylinder 102 ... Laser beam axis 102A ... Beam profiler beam axis 103 ... Moving axis

Claims (13)

A laser light source, an imaging optical system provided on the optical axis of the laser light from the laser light source, and an irradiated surface that is provided at an imaging position of the imaging optical system and is to be irradiated with the laser light is annealed An X-Y-Z stage that movably supports a substrate to be processed, a wavelength conversion member that converts the laser light into visible light, and an image that magnifies and captures a visible light image displayed on the wavelength conversion member The processing target using a laser annealing apparatus comprising: a magnifying optical system having an apparatus; and a height sensor for measuring a relative height position of a processing target substrate on the XYZ stage with respect to the imaging optical system. When monitoring the light intensity distribution of the laser light that anneals the substrate,
Trisodium 8-hydroxy-1,3,6-pyrenetris having a desired spatial resolution for displaying the light intensity distribution image of visible light by converting the laser light into visible light at the position of the substrate to be processed A step of installing a wavelength conversion member containing rufonate;
By measuring the height position of the wavelength conversion member installed at the position of the substrate to be processed with the height sensor and adjusting the height position to be stored in advance, the wavelength conversion member is flush with the substrate to be processed. Aligning the
A step of emitting from the laser light source a laser light selected from an energy amount of the laser light from the laser light source selected so that the wavelength conversion member does not deteriorate or evaporate;
Imaging a light intensity distribution image of visible light displayed on the wavelength conversion member with an imaging device;
First, a light intensity distribution image of visible light in which the light intensity distribution of laser light to be annealed on the substrate to be processed is displayed on the wavelength conversion member is picked up by an imaging device , and the light intensity and light intensity distribution image of the laser light are captured. And detecting the detection result as a target value in advance and storing it,
And the imaging in order to control the height position of the wavelength conversion member to match the light intensity distribution image and intensity of the target value which the light intensity distribution image and the light intensity is stored in advance taken by the imaging device Monitoring a minute visible light image having a light intensity distribution;
Storing the height position of the wavelength conversion member measured by the height sensor;
The wavelength conversion member is retracted, the substrate to be processed is moved to a position where the wavelength conversion member was present, the stored target value is called, and the substrate to be processed corresponding to the target value from the laser light source Irradiating the substrate to be processed with laser light having light intensity and light intensity distribution of an energy amount for annealing
A light intensity distribution monitoring method characterized by comprising: Intermittently irradiating the wavelength conversion member with the invisible light selected to an energy amount that the wavelength conversion member does not deteriorate or evaporate, and obtaining a light intensity distribution of the invisible light in synchronization with the intermittent irradiation. The method of claim 1, characterized in that: 3. The magnification ratio of the magnifying optical system is in the range of 2 to 2000 times in order to form large-sized crystal grains having a diameter of several microns to more than 10 microns. The method according to claim 1. 4. The method according to claim 1, wherein a size of a detection visual field of the light intensity distribution in the magnifying optical system is 100 μm × 100 μm or less and a spatial resolution is 5 μm or less. 5. The spatial resolution of the magnifying optical system is 0.2 to 10 [mu] m in order to accurately measure the light intensity distribution in the observation region of several tens of microns. Method. The method according to claim 1, wherein the wavelength conversion member has an average film thickness of 1 nm or more and 3 μm or less so that the spatial resolution does not decrease. 2. A filter that absorbs or reflects invisible light and transmits only visible light is disposed in an optical path between the wavelength conversion member and the magnifying optical system in order to avoid adverse effects due to invisible light. The method of any one of thru | or 6. A laser light source;
An imaging optical system and a phase shifter provided on the optical axis of the laser light from the laser light source;
A stage that is provided at an imaging position of the imaging optical system and that is movable in the X, Y, and Z directions for supporting the substrate to be irradiated on which the laser beam is irradiated;
A beam profiler for monitoring the light intensity distribution of the laser beam;
An annealing apparatus comprising:
The beam profiler is
A wavelength conversion member containing trisodium 8-hydroxy-1,3,6-pyrenetrisulfonate having a desired spatial resolution for converting the laser light into visible light and displaying a light intensity distribution image of visible light When,
An magnifying optical system having an imaging device that captures a visible light image displayed on the wavelength conversion member;
A height sensor for detecting a height position of the wavelength conversion member;
The wavelength conversion member is aligned and controlled so that the measurement result of the height sensor is at a pre-stored height position, and the energy amount of laser light from the laser light source does not deteriorate or evaporate. Controlling so that the laser beam selected for the amount of energy is emitted from the laser light source, and the light intensity distribution of the laser beam that should first anneal the substrate to be processed is displayed on the wavelength conversion member. An intensity distribution image is captured by the imaging device, the light intensity of the laser light and the light intensity distribution image are detected, the detection result is set and stored as a target value in advance, and the light intensity captured by the imaging device height position of the wavelength conversion member as distribution image and intensity matches the light intensity distribution image and intensity of the target value stored in advance Control is possible, and to store the height position of the wavelength conversion member, and is retracted through the wavelength conversion member, moving the target substrate in position, calling the target value that has been said memory, said A computer that performs control to irradiate the target substrate with laser light having a light intensity and a light intensity distribution of an energy amount for annealing the target substrate corresponding to the target value from a laser light source;
An annealing apparatus comprising: 9. An annealing apparatus according to claim 8, wherein the enlargement magnification of the enlargement optical system is in the range of 2 to 2000 times in order to form large-sized crystal grains having a diameter exceeding several microns to 10 microns. 10. The annealing apparatus according to claim 8, wherein the wavelength conversion member has an average thickness of 1 nm or more and 3 μm or less so that the spatial resolution does not decrease. An annealing method for annealing a substrate to be processed using the annealing apparatus according to any one of claims 8 to 10,
When detecting the light intensity distribution of the invisible light, the substrate to be processed and the wavelength conversion member move the substrate to be processed on the invisible light path, and then move the wavelength conversion member onto the invisible light path. A wavelength converting member moving step to be performed;
The invisible light controlled to an energy amount that does not cause the wavelength conversion member to deteriorate or evaporate is emitted from the light source to the substrate to be processed moved on the invisible light path, and the light intensity distribution of the transmitted light transmitted through the phase shifter is detected. A light intensity distribution detection step to perform,
An annealing method comprising the steps of: When the light intensity distribution of the transmitted light that has passed through the phase shifter is detected, the detected light intensity distribution is collated with a predetermined light intensity distribution, and if they are different, the wavelength conversion is performed. The substrate to be processed is positioned at a position of a member, invisible light having a predetermined energy amount necessary for processing the substrate to be processed is emitted from the light source, and the substrate to be processed is annealed. The annealing method according to claim 11. A laser light source;
A phase shifter for forming a beam profile in which the light intensity is minimized in the phase shift unit provided on the optical axis of the laser light from the laser light source;
An imaging optical system provided on an optical axis of laser light from the laser light source;
An object to be processed includes an amorphous semiconductor layer that is provided at an image forming position of the image forming optical system and in which an irradiated surface is irradiated with a laser beam having a beam profile in which the light intensity is minimized in the phase shift unit. A stage that can move in the X, Y, and Z directions to support the substrate;
A beam profiler for monitoring the light intensity distribution of the laser beam;
A crystallization apparatus comprising:
The beam profiler is
Trisodium 8-hydroxy-1 having a desired spatial resolution in order to display a light intensity distribution image of visible light by converting laser light having a beam profile with a minimum light intensity in the phase shift unit into visible light. , 3,6-pyrene trisulfonate-containing wavelength conversion member;
An magnifying optical system having an imaging device that captures a visible light image of a beam profile in which the light intensity is minimized in the phase shift unit displayed on the wavelength conversion member;
A height sensor for detecting a height position of the wavelength conversion member;
After the wavelength conversion member is aligned and controlled so that the measurement result of the height sensor is at a pre-stored height position, the energy by which the wavelength conversion member does not deteriorate or evaporate the energy amount of the laser light from the laser light source The laser light source selected in quantity is controlled to be emitted from the laser light source , and the light intensity distribution of the laser light to be annealed on the substrate to be processed first is displayed on the wavelength conversion member. The distribution image is imaged by the imaging device, the light intensity of the laser light and the light intensity distribution image are detected, the detection result is set and stored in advance as a target value, and the phase shift imaged by the imaging device light intensity distribution of the target value which the light intensity distribution image and intensity of the beam profile which the light intensity becomes minimum is stored in advance in the parts And intensity and controlling the height position of the wavelength conversion member to match, and to store the height position of the wavelength conversion member, and is retracted through the wavelength conversion member, the substrate to be treated at that position , The stored target value is recalled, and the laser beam having the light intensity and light intensity distribution of the amount of energy for annealing the target substrate corresponding to the target value from the laser light source A computer that controls to irradiate
A crystallization apparatus comprising:

Images