JP3199548B2 - Exposure apparatus and exposure method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus and an exposure method .

[0002]

2. Description of the Related Art In general, in a semiconductor manufacturing process, a photoresist film is formed on a surface of a semiconductor wafer, a fine circuit pattern of a mask is transferred to the photoresist film by a photolithography technique, and this is etched after development. To perform fine processing. In the case of forming a photoresist film on the wafer surface described above, generally, a photoresist solution is dropped on the central portion of the wafer surface, and the dropped solution is spin-coated at a high speed to diffuse and apply the liquid onto the entire surface by centrifugal force. Spinner method is used.

When a photoresist film is formed over the entire surface of a wafer by the above-described spinner method, the photoresist film formed on the peripheral portion of the wafer is mechanically peeled off during handling during wafer transfer in a later step. As a result, the particles may be scattered as particles, which may lower the yield of the integrated circuits formed on the semiconductor wafer. Therefore, such a photoresist film on the peripheral portion of the wafer is removed in advance.

As an apparatus for removing a photoresist film at a peripheral portion of a wafer, for example, JP-A-58-159535, JP-A-59-138335, and JP-A-59-1
As disclosed in Japanese Patent No. 58520, JP-A-61-73330, etc., the photoresist film at the peripheral portion of the wafer is irradiated with light, for example, ultraviolet light, while rotating the wafer, and is exposed to light. The removal of the resist film at the peripheral portion has been performed.

[0005]

However, in the conventional exposure apparatus, when the peripheral portion of the wafer is irradiated with light, the wafer is exposed to a sudden increase in temperature due to light energy or a chemical reaction caused by ultraviolet rays. When the solvent contained in the resist film evaporates, bubbles are generated in the resist film applied to the resist film, and when the bubbles pierce the surface of the resist film, fragments of the resist are scattered, thereby causing particles. If such particles adhere to the device forming surface of the wafer, they will be left undeveloped during the development process of the wafer and lower the yield, so that it is necessary to surely remove particles generated during exposure. Having.

SUMMARY OF THE INVENTION An object of the present invention is to provide an exposure apparatus and an exposure method capable of reliably removing particles at the time of exposure and improving the yield of an object to be processed.

[0007]

According to the present invention, there is provided: (1) an exposure apparatus for irradiating light to a peripheral portion of an object to be processed on which a processing film is formed and exposing the peripheral portion to light; Exposure means for irradiating light to the periphery of the body to expose the portion, exhaust means surrounding the exposure means, and gas blowing means for blowing gas toward the light irradiation part of the object to be processed An exposure apparatus comprising:
The means is provided inside the exhaust means.
Or the exhaust means is the object to be processed of the exposure means.
A first exhaust unit provided on the inner side,
And second exhaust means provided on the outer side of the object to be processed.
And the gas blowing means is provided in the first exhaust means.
It is characterized by having been done . Also, (2)
Irradiate light to the periphery of the object on which the processing film is formed
An exposure apparatus for exposing a peripheral portion, wherein
Light is illuminated on the mounting table on which the body is
Exposure means for irradiating the exposed portion,
Gas blowing means for blowing gas toward the light irradiation unit
And a rotation mechanism for rotating the mounting table,
And the rotation mechanism is integrated horizontally and / or vertically.
And a moving mechanism for moving in a vertical direction.
An exposure apparatus is provided. Further, (3) the object to be processed on which the processing film is formed is mounted on a mounting table,
Irradiates the part with light from the exposure means and exposes the part to the periphery
An exposure method for processing, wherein the mounting table and / or
By moving the exposure means, the object and the exposure means
A step of adjusting the distance, after this step, characterized by comprising a step of exposing the portion while blowing a gas into that portion while exhausting the light irradiation portion of the peripheral edge portion of the workpiece An exposure method is provided.

[0008]

According to the present invention , particles exposed from the surface of the processing film due to gas generated from the processing film formed on the processing object when the peripheral portion of the processing object is exposed by the exposure means. Gas from the gas blowing means to the light irradiating section
In addition to being suppressed by the attachment, the scattered particles can be surely exhausted and removed by the exhaust means surrounding the exposure means.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An exposure apparatus according to one embodiment of the present invention will be described below with reference to the drawings. First, the configuration of the exposure apparatus will be described with reference to FIGS.

As shown in FIG. 1, the exposure apparatus 1 is surrounded by a housing (not shown), and has a flat wafer holding surface inside for holding an object to be processed, for example, a semiconductor wafer W by suction. Disk-shaped spin chuck 2
Is arranged. A vacuum suction hole 3 connected to a vacuum device (not shown) is provided at the center of the wafer holding surface of the spin chuck 2 so that the wafer W can be sucked and held. A rotating mechanism, for example, a spin motor 4 is connected to a lower end of the spin chuck 2, and is configured to rotate the spin chuck 2. The spin motor 4 is provided on, for example, a horizontal / vertical movement mechanism (not shown), and is configured to be able to move the spin chuck 2 itself in the horizontal (X, Y) direction and the vertical (Z) direction.

An exposing means 6 for exposing the peripheral portion 5 is provided above the peripheral portion 5 of the wafer W sucked and held by the spin chuck 2. The exposing means 6 has a light irradiating section 7 to which an optical path 8 formed by, for example, an optical fiber or the like is connected via a coupling section 9, such as a mercury lamp or xenon. From a light source 10 such as a lamp, light, for example, ultraviolet light can be propagated to the light irradiating section 7 and radiated toward the peripheral portion 5 of the wafer W outside the region of the device formed on the wafer W. Is configured.

The exhaust means 50 surrounds the periphery of the light irradiating section 7. For example, both ends of the coupling section 9 are arranged side by side with the light irradiating section 7 so as to be in the center direction and the outer peripheral direction of the wafer W. Each side holds an exhaust duct 11 (first exhaust means) and an exhaust duct 12 (second exhaust means). One end of the exhaust duct 11 on the center direction side of the wafer W is as shown in FIG. An exhaust port 13 bent at an angle of α degrees is provided on the side of the light irradiation section 7.
The other end is connected to an exhaust pipe 14 as shown in FIG. 1, and the exhaust pipe 14 is connected to an exhaust device, for example, a vacuum pump 1 via an on-off valve for controlling exhaust gas flow, for example, a butterfly valve 15.
6 is connected.

Further, a gas blowing means 17 is built in the exhaust duct 11, and the gas blowing means 17 is, as shown in FIG.
For example, there is provided an injection nozzle 18 for spraying N2 gas to the light irradiation portion of the wafer W. The injection nozzle 18 has a nozzle inner diameter of, for example, 1 to 2 mm, and is bent outward of the wafer W and has an opening angle of β degrees. And this injection nozzle 1
8 is connected to a gas supply pipe 19,
Is connected to an inert gas source 21 via a flow control device for adjusting the gas flow, for example, a mass flow controller (MFC) 20.

The suction side end of the exhaust duct 12 on the outer peripheral side of the wafer W is connected to the wafer W as shown in FIG.
Has an exhaust port 22 that opens to the vicinity of the back side of the peripheral edge of
The other end of the exhaust duct 12 is connected to an exhaust pipe 23 as shown in FIG. 1, and the exhaust pipe 23 is connected to an exhaust device, for example, a vacuum pump 2 via an on-off valve, for example, an electromagnetic valve 24.
5 is connected.

The light irradiating section 7,
A rotation mechanism 26 is provided for simultaneously rotating the gas blowing means 17 and the exhaust ducts 11 and 12 from above the wafer W toward the back surface or from below the wafer W toward the surface. Is constituted by connecting a connecting column 9 and a base 28 which can be freely moved in the θ direction by a driving means, for example, a stepping motor M, which is axially connected to a rotating rail 27, for example, a ball bearing, by a supporting column 29. I have.

The operation of exposing the periphery of the semiconductor wafer W in the exposure apparatus configured as described above will be described.

As shown in FIG. 2, a photoresist film 30
The light irradiating unit 7 and the gas spraying unit 17 are arranged above the peripheral portion of the wafer W on which the
After moving through the exhaust ducts 11 and 12, the distance L between the surface of the wafer W and the light irradiation unit 7 is moved by the horizontal / vertical moving mechanism.
1 may move to a distance where the influence of light interference is reduced, for example, about 0.5 to 1.0 mm in a range where they do not come into contact with each other, and may come into contact with the peripheral edge of the wafer W when the wafer W is handled and peel off. Width L2, for example, 3-5 m
Move about m. By rotating the spin motor 4 in this state, the wafer W is rotated and the light source 1 is rotated.
The light irradiating section 7 irradiates the light generated by operating 0 to the periphery of the wafer from the light irradiating section 7 to expose the photoresist film 30 which is a processing film in this portion.

At the same time as this exposure operation, the gas blowing means 17 is driven so that the inert gas, for example, N ₂ gas, from the inert gas source 21 is directed from the injection nozzle 18 to the exposed portion toward the outside of the wafer W. At the same time, the exhaust device 25 is driven to open the on-off valve 24, and the atmosphere near the peripheral portion of the wafer W is exhausted from the exhaust duct 12. At the time of this peripheral exposure, as shown in FIG. 2, a strong ultraviolet ray V is applied, so that the solvent contained in the resist film 30 is vaporized from the resist portion at the peripheral portion of the wafer due to a temperature rise or a chemical reaction. As a result, bubbles 31 are generated, and the bubbles 31 break through the surface of the resist film 30 and become particles 32 and scatter. In order to suppress the generation of the particles 32, N ₂ gas is blown to the peripheral portion of the wafer to be exposed by the gas blowing means 17 to cause a cooling effect to the peripheral portion of the wafer to be exposed, thereby suppressing a rise in the temperature of the resist film. This suppresses the amount of generated bubbles 31 and particles.

Further, the particles 32 that could not be suppressed by the gas blowing means 17 are removed.
The wafer W is conveyed toward the outside of the wafer W by the N ₂ gas ejected from the ejection nozzle 18, and is discharged into the exhaust duct 12. In this process, most of the particles 32 are discharged into the exhaust duct 12, but the particles 32 that are not discharged into the exhaust duct 12 and scatter a small amount toward the center of the wafer W are removed by the exhaust device shown in FIG. 1
6 is driven and the injection nozzle 18 is driven by the butterfly valve 15.
Is discharged from the exhaust duct 11 on the side that incorporates the gas blowing means 17 that is set to an exhaust amount that does not cause backflow of the N ₂ gas injected from the exhaust duct 11.

Next, as shown in FIGS. 3 and 4, the light irradiating section 7, the gas blowing means 17 and the exhaust ducts 11 and 12 are interlocked by the rotating mechanism 26 to rotate from above the wafer W toward the back. Then, the resist film 30 on the periphery of the wafer W is exposed from the upper surface to the side surface of the wafer W and from the side surface to the lower surface. At this time, the exhaust amount of the exhaust duct 11 is controlled by controlling the butterfly valve 15 so that the N ₂ gas injected from the injection nozzle 18 does not hinder the processing, and the setting of the exhaust amount is increased. When the processing moves to the side surface, as shown in FIG. 3, the flow angle of the N ₂ gas injected from the injection nozzle 18 at the edge of the wafer W changes, so that the amount of the N ₂ gas flowing in the direction of the exhaust duct 12 is slightly reduced. This is because the amount of N ₂ gas flowing in the direction of the exhaust duct 11 slightly increases, and the number of particles 32 conveyed thereby also increases.

Then, as shown in FIG. 4, after the resist film 30 on the peripheral edge of the lower surface of the wafer W is exposed to light, the rotation of the spin motor 4 is stopped, and ultraviolet rays V and gas spraying means for irradiating from the light irradiating unit 7 The exhaust operation of the N ₂ gas and the exhaust means 11 and 12 from the injection nozzle 18 is stopped, and the wafer is moved to the upper peripheral portion of the wafer W by the rotating mechanism 26 shown in FIG.

Next, as shown in FIG. 5, the peripheral portion 34 of the wafer W is processed by the above-described process, but the peripheral portion 36 of the orientation flat (orientation flat) portion 35 formed on the wafer W is unprocessed. The peripheral portion 36
When the horizontal and vertical movement mechanism reciprocates in the Y direction so that the peripheral edge portions 36 of the wafer W are uniformly irradiated with the ultraviolet rays V from the light irradiating portion at the same interval, the rotation is performed. By the mechanism 26, the light irradiation unit 7, the gas blowing means 17 and the exhaust ducts 11 and 12 are rotated in an interlocking manner from above the wafer W toward the back surface, and the peripheral resist film 30 of the wafer W is moved from the upper surface to the side surface of the wafer W. Then, the same exposure processing as described above is performed from the side surface to the lower surface, and the exposure processing on the peripheral portion of the wafer W ends.

The effect of the present embodiment having the above-described configuration will be described. By spraying N ₂ gas on the wafer edge to be exposed by the gas spraying means 17 during the exposure process, a cooling effect is generated at the wafer edge to be exposed, and the temperature rise of the resist film is suppressed. The generation amount of bubbles 31 and particles generated can be suppressed, and the injection nozzle 18 of the gas blowing unit 17 can be further reduced.
Particles 32 scattered from the resist film 30 are forcibly conveyed to the outside of the device forming surface of the wafer W and discharged into the exhaust duct 12 by the inert gas ejected from the wafer W, and scatter a small amount toward the center of the wafer W. Since the particles 32 are also discharged into the exhaust duct 11, the particles 32 can be reliably removed, and the particles 32 can be prevented from adhering to the wafer W.

Accordingly, the yield of devices formed on the wafer W can be improved without lowering the throughput of the exposure processing.

Further, even in the case where the exposure process is performed from the upper surface to the side surface and from the side surface to the lower surface of the wafer W by the rotating mechanism 26, the scattering of the particles 32 can be achieved by appropriately setting the exhaust amount of the exhaust duct 11 by the butterfly valve 15. Even if the amount of the particles scatters toward the center of the wafer W changes, the particles 32 can be reliably removed by following the change.

Next, the second embodiment shown in FIG. 6 will be described.
The exhaust duct 51 is connected via a pipe 19 to an exhaust control device for setting an exhaust amount to a predetermined exhaust amount, for example, a mass flow controller (MFC) 20, and further, is connected to the mass flow controller (MFC). 2
0 is connected to an exhaust device, for example, a vacuum pump 16. Further, a gas blowing means 17 is arranged outside the exhaust duct 51, and the gas blowing means 17 is configured to blow an inert gas, for example, N ₂ gas, to the light irradiation portion of the wafer W. By this <br/> and such a configuration, particles generated from the light irradiated portion of the wafer W is conveyed to above the light irradiation unit, without scattering particles in the opening portion outside of the exhaust duct 51, exhaust duct 51
Exhaust can be removed within the opening area of
It can be achieved.

Next, the third embodiment shown in FIG. 7 will be described.
The exhaust duct 51 is connected via a pipe 19 to an exhaust control device for setting an exhaust amount to a predetermined exhaust amount, for example, a mass flow controller (MFC) 20, and further, is connected to the mass flow controller (MFC). 2
0 is connected to an exhaust device, for example, a vacuum pump 16. Further, a gas blowing means 17 is arranged inside the exhaust duct 51, and the gas blowing means 17 is configured to blow an inert gas, for example, an N ₂ gas, to the light irradiation portion of the wafer W. With this configuration, the gas flow generated by the inert gas, for example, N ₂ gas blown by the gas blowing means 17 does not cause a turbulence in the airflow near the duct 51, and further, no fluid flow atmosphere is generated outside the duct 51. Particles generated from the light irradiating section are surely transported above the light irradiating section,
The particles can be removed within the opening area of the exhaust duct 51 without scattering the particles outside the opening of the exhaust duct 51, and the size of the exposure apparatus can be further reduced.

Next, a fourth embodiment shown in FIG. 8 will be described.
, And the inside of the exhaust duct 51 is divided into a plurality of chambers by a partition wall 52, and the plurality of chambers are each independently controlled to a predetermined amount of exhaust. Mass flow controller (MFC)
Pipes 19, 1 to 20, 20a, 20b, 20c, 20d
9a, 19b, 19c, and 19d, and further connected to mass flow controllers (MFC) 20, 20a,
20b, 20c, 20d are connected to an exhaust device, for example, a vacuum pump 16, 16a, 16b, 16c, 16d, respectively. With this configuration, an inert gas such as N ₂ blown by the gas blowing means 17 is used.
Even when the gas acts on the wafer W and is reflected by the gas to cause turbulence in the airflow, the MFCs 20, 20a, 20b, 20c, 2
0d, and by setting the exhaust amount of the chamber in the direction in which the turbulence of the N ₂ gas flow or the amount of reflection is large, the N ₂ gas is reduced.
> Particles that are further conveyed are reliably conveyed to the chamber and can be exhausted and removed.

The exposure operation of the peripheral portion of the wafer in this embodiment may be performed in any process after forming a photoresist film on the wafer surface, for example, a pre-bake process for improving the adhesion of the resist film. and, before or after process of the mask pattern processing, or may be performed immediately before the step of the development process not to mention, also, the processing of the orientation flat portion and the orientation flat portion other than the wafer may be performed any order, also Although the N ₂ gas was used as the blowing gas, the invention is not limited to this. For example , another inert gas such as CO ₂ gas or Ar gas may be used.
May be used , or clean air may be used . Further, the case where a semiconductor wafer is used as the object to be processed has been described. However, the present invention is not limited to this, and it is needless to say that the present invention can also be applied to spin coating of a magnetic material onto an LCD substrate or a disk-shaped floppy disk.

[0030]

According to the present invention, since particles generated during the exposure processing of the object to be processed can be reliably exhausted and removed, the particles can be prevented from adhering to the object to be processed.
Thus, there is a remarkable effect that the yield of the object to be processed can be improved.

[0031]

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an exposure apparatus to which a first embodiment according to the present invention is applied.

FIG. 2 is a partial sectional view of the exposure apparatus of FIG.

FIG. 3 is an operation explanatory diagram illustrating an operation of the exposure apparatus of FIG. 1;

FIG. 4 is an operation explanatory diagram illustrating an operation of the exposure apparatus of FIG. 1;

FIG. 5 is an operation explanatory diagram illustrating an operation of processing the orientation flat portion of the object by the exposure apparatus of FIG. 1;

FIG. 6 is a schematic plan view illustrating another embodiment.

FIG. 7 is a schematic plan view illustrating another embodiment.

FIG. 8 is a schematic plan view illustrating another embodiment.

DESCRIPTION OF THE REFERENCE NUMERALS 1 Exposure device 6 Exposure means 11 Exhaust duct (first exhaust means) 12 Exhaust duct (second exhaust means) 17 Gas blowing means 26 Rotating mechanism 30 Resist film 31 Bubbles 50 Exhaust means W Semiconductor wafer (Object to be processed)

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/027 G03B 27/32 G03B 27/52 G03F 7/20 521

Claims (12)

(57) [Claims] 1. An exposure apparatus for irradiating light to a peripheral portion of an object to be processed on which a processing film is formed and performing an exposure process on the peripheral portion, the method comprising irradiating light to the peripheral portion of the object to be processed. Exposure means for exposing a portion, exhaust means surrounding the exposure means, and gas blowing means for blowing gas toward a light irradiation part of the object to be processed , wherein the gas blowing means Installed inside the exhaust means
An exposure apparatus comprising: 2. The method according to claim 1, wherein the processing film is formed on a peripheral portion of an object to be processed.
An exposure apparatus for irradiating light to expose the peripheral portion.
Irradiating the peripheral portion of the object with light to expose the portion.
Exposure means, an exhaust means surrounding the exposure means, and a gas for blowing a gas toward a light irradiation part of the object to be processed.
With spraying meansAnd The exhaust means is provided on the inner side of the inside of the object to be processed of the exposure means.
The first exhaust means,
And second exhaust means provided on one side,
The spraying means is provided inside the first exhaust means.
 An exposure apparatus comprising: 3. An exposure apparatus for irradiating a peripheral portion of an object on which a processing film is formed with light to perform an exposure process on the peripheral portion, comprising: a mounting table on which the object is mounted; Exposure means for irradiating the peripheral portion of the processing object with light to expose the portion, gas blowing means for blowing gas toward the light irradiation part of the processing object, a rotating mechanism for rotating the mounting table, An exposure apparatus, comprising: a moving mechanism for integrally moving the mounting table and the rotation mechanism in a horizontal direction and / or a vertical direction. 4. The exposure apparatus according to claim 3 wherein said gas blowing means, characterized in that it is internally provided to the exhaust unit. In wherein said exhaust means includes a first exhaust means provided in the object to be treated inside lateral side of said exposure means, a second exhaust means provided in the treated outside lateral side of said exposure means 4. An exposure apparatus according to claim 3 , wherein said gas blowing means is provided inside said first exhaust means. Wherein said gas blowing means comprises a nozzle for spraying the gas, this nozzle is claims 1 to 5, characterized in that the tip portion is bent outwardly of the workpiece The exposure apparatus according to any one of the above items. 7. The exhaust means is divided into a plurality of chambers by partition walls, and further comprises exhaust control means for independently controlling the amount of exhaust in each of the plurality of chambers. The exposure apparatus according to any one of claims 1 to 6 . 8. The exhaust device according to claim 1, wherein the exhaust means has an exhaust port at an end of the object to be processed, the exhaust port being opened in the vicinity of the back surface side of the peripheral portion of the object to be processed. The exposure apparatus according to claim 1. 9. The exposure means, the gas blowing means,
And said exhaust means, integrally, any one of claims 1 to 8, wherein, further provided with the rotating mechanism for rotating between upper and lower positions of the object
Exposure apparatus according to Item. 10. An exposure method in which an object to be processed on which a processing film is formed is mounted on a mounting table, and a peripheral portion of the processing object is irradiated with light from exposure means to expose the portion. And / or adjusting the distance between the object to be processed and the exposure means by moving the exposure means. After this step, the gas irradiating part at the periphery of the object is exhausted while gas Exposing the portion while spraying. 11. The exposure according to claim 10, wherein in the exposing step, the exposing means is moved to sequentially perform an exposing process on a front side, a side, and a back side of a peripheral portion of the object to be processed. Method. 12. An exposure method in which a semiconductor wafer having an orientation flat portion on which a processing film is formed is mounted on a mounting table, and light is radiated from the exposure means to the peripheral portion to expose the peripheral portion. Wherein the mounting table and / or the exposing means are moved so that the distance between the semiconductor wafer and the exposing means is adjusted such that light is irradiated to a peripheral portion of the semiconductor wafer other than the orientation flat portion. Adjusting, exposing a light irradiating portion of a peripheral portion of the semiconductor wafer other than the orientation flat portion while exposing the portion while exposing the portion to gas, and exposing the mounting table and / or the exposure means. By moving the semiconductor wafer, the distance between the semiconductor wafer and the exposing means is adjusted so that light is applied to the periphery of the orientation flat portion of the semiconductor wafer. Adjusting the laser beam to be irradiated, and exposing the light emitting portion at the periphery of the orientation flat portion of the semiconductor wafer while blowing gas to the portion while exhausting the light irradiated portion. Exposure method.