JP6920469B2 - Light irradiation device - Google Patents

Description

The present disclosure relates to a light irradiation device that irradiates a substrate with light.

Patent Document 1 describes a step of forming a resist film on the surface of a substrate, a step of exposing, a step of patterning a resist, and a step of irradiating the front surface of the resist with light having a wavelength of 200 nm or less in the process of manufacturing a semiconductor device. It is described that the step of etching the lower layer film of the resist film and the step of etching the lower layer film of the resist film are performed in order. The step of irradiating light having a wavelength of 200 nm or less (hereinafter, simply referred to as a step of irradiating light) is performed for the purpose of improving, for example, the roughness (unevenness) of the resist film.

Japanese Patent No. 3342856

When the above-mentioned step of irradiating a substrate having a diameter of about 300 mm with the above-mentioned light is carried out, a plurality of lamps are arranged on the substrate from the viewpoint of ensuring the irradiation intensity while shortening the irradiation distance. Here, each lamp is a point light source, and the irradiation range on the wafer is circular. When the irradiation range is circular, if the lamps are arranged so that the irradiation ranges of the lamps do not overlap, there will be a portion where the light is not irradiated (or the irradiation intensity is weakened). On the other hand, in order to prevent a portion where the irradiation intensity is weakened, it is necessary to overlap a part of the irradiation range of each lamp, and in this case, the problem is that the irradiation intensity of the overlapping portion becomes extremely strong. It becomes. As described above, in the configuration in which the substrate is irradiated with light by a plurality of lamps, it is difficult to uniformly irradiate the irradiation surface of the substrate with light.

Therefore, the present disclosure describes a light irradiation device capable of improving the uniformity of the light irradiation distribution on the irradiation surface of the substrate.

The light irradiating device according to one aspect of the present disclosure includes a plurality of light irradiating portions that irradiate a substrate with vacuum ultraviolet light having a conical light path with a light source as an apex, and a vacuum irradiating from the plurality of light irradiating portions. It is provided with a light-shielding portion provided corresponding to each light irradiation portion so as to block the overlapping portion of the ultraviolet light irradiation range, and the light-shielding portion is formed in a polygonal shape when viewed from the traveling direction of the vacuum ultraviolet light. ing.

In the light irradiation device of the present disclosure, a plurality of overlapping portions of vacuum ultraviolet light that are irradiated toward a substrate by taking a conical optical path are shielded by a polygonal light-shielding portion provided corresponding to each light irradiation portion. Has been done. Here, when light is irradiated to the substrate from a plurality of point light sources having a circular irradiation range on the substrate, if the point light sources are arranged so that the irradiation ranges of the lights do not overlap, the irradiation range is circular. There will be a part that is not irradiated with light (or a part where the irradiation intensity is weakened). On the other hand, in order to prevent a part that is not irradiated with light (or a part where the irradiation intensity is weakened), it is necessary to overlap a part of the irradiation range of the light emitted from each point light source. The problem is that the irradiation intensity of the overlapping portion becomes extremely strong. As described above, in the conventional configuration in which the substrate is irradiated with light from a plurality of light sources, it is difficult to uniformly irradiate the irradiation surface of the substrate with light. In this respect, in the light irradiation device of the present disclosure, a light-shielding portion that shields the overlapping portion of a plurality of vacuum ultraviolet lights is formed in a polygonal shape when viewed from the traveling direction of the vacuum ultraviolet light. As a result, the irradiation range of each vacuum ultraviolet light on the substrate becomes polygonal. As a result, unlike the case where the irradiation range is circular, it is possible to suppress the occurrence of a portion where the light is not irradiated (or a portion where the irradiation intensity is weakened) while preventing the irradiation ranges from overlapping. That is, according to the light irradiation device of the present disclosure, the uniformity of the light irradiation distribution on the irradiation surface of the substrate can be improved.

The light-shielding portion may have a tubular light-shielding member that extends in the traveling direction of the vacuum ultraviolet light and is formed in a tubular shape. Since the light-shielding portion provided corresponding to the light-irradiating portion extends in the height direction (the traveling direction of vacuum ultraviolet light) and is formed in a tubular shape, the light-shielding portion is irradiated with light other than the corresponding light-irradiating portion. The influence of vacuum ultraviolet light from a part (for example, an adjacent light irradiation part) can be appropriately eliminated. That is, it is possible to appropriately prevent the irradiation range from overlapping with the vacuum ultraviolet light of the other light irradiation unit, and to further improve the uniformity of the light irradiation distribution on the irradiation surface of the substrate.

A separation distance adjusting portion for adjusting the separation distance of the light-shielding portion from the substrate may be further provided. Since the light-shielding portion (particularly the tubular light-shielding portion) is provided, the shadow of the light-shielding portion is projected on the irradiation surface of the substrate, and the shadow may deteriorate the uniformity of the light irradiation distribution on the irradiation surface of the substrate. There is. In this regard, by adjusting the height of the light-shielding portion (distance from the substrate) by the separation distance adjusting portion, for example, the spread of the irradiation light from the adjacent light-shielding portion to the substrate can be adjusted, and the irradiation light can be adjusted. It is possible to eliminate the shadowed part by overlapping the above with each other.

The light irradiation unit may be configured to include a deuterium lamp. By using a deuterium lamp, the substrate can be irradiated with near-ultraviolet light having a wavelength larger than 200 nm in addition to vacuum ultraviolet light having a wavelength of 200 nm or less. As described above, since the wavelength range of the spectrum of the light emitted from the deuterium lamp is relatively wide, for example, when a resist pattern is formed on the surface of the substrate, the resist pattern can transfer light energies of various wavelengths. Will receive. As a result, various reactions occur on the surface of the resist pattern to increase the fluidity, and as a result, the effect of improving the roughness of the surface can be improved.

The deuterium lamp may generate vacuum ultraviolet light having a wavelength of 200 nm or less, for example, a wavelength of 160 nm or less. In a deuterium lamp, for example, 160 nm or less is the peak wavelength of the continuous spectrum. Therefore, by generating vacuum ultraviolet light of 160 nm or less, for example, when a resist pattern is formed on the surface of the substrate, the surface is roughened. The improvement effect of can be further improved.

At least one of the illuminance value of the vacuum ultraviolet light to be irradiated, the light ray angle of the vacuum ultraviolet light to be irradiated, and the separation distance from the substrate may be different from each other in the plurality of light irradiation units. In this way, the irradiation distribution can be positively adjusted by making the illuminance value, the light beam angle, or the height of the light irradiation unit (distance from the substrate) different from each other for the plurality of light irradiation units. Depending on the irradiation situation, the uniformity of the light irradiation distribution on the irradiation surface of the substrate can be further improved.

A diffuser portion that diffuses vacuum ultraviolet light may be further provided above the light-shielding portion. Irradiation light has variations in intensity due to the internal electrode structure of the light source (lamp). In this respect, by providing the diffusing portion above the light-shielding portion, the variation of the irradiation light is averaged, and the uniformity of the light irradiation distribution on the irradiation surface of the substrate can be further improved.

A substrate rotating portion that rotates the substrate with the irradiation surface of the substrate facing the light irradiation portion may be further provided. As a result, the irradiation location changes, so that the uniformity of the light irradiation distribution on the irradiation surface can be further improved.

A parallel moving portion that reciprocates the light-shielding portion or the substrate in a direction parallel to the irradiation surface of the substrate may be further provided. Even in this case, since the irradiation location changes, the uniformity of the light irradiation distribution on the irradiation surface can be further improved. In the mode of reciprocating in the direction parallel to the irradiation surface, unlike the mode of rotating the substrate, a portion where the irradiation location does not change (for example, the center of rotation) is unlikely to occur. Further, the light-shielding portion may be made of a material having a reflectance of 90% or less of vacuum ultraviolet light.

The tubular light-shielding member may extend in the traveling direction over substantially the entire area between the light irradiation unit and the substrate. As a result, it is possible to more appropriately suppress the overlap of the irradiation range with the vacuum ultraviolet light of the other light irradiation unit.

The tubular light-shielding member may be provided at a position closer to the substrate between the light irradiation unit and the substrate. When vacuum ultraviolet light is used, it is necessary to evacuate with a vacuum pump to bring the processing chamber into a hypoxic state. When the tubular light-shielding member is provided in substantially the entire area between the light irradiation unit and the substrate, it becomes difficult to evacuate by the vacuum pump in the processing chamber, and the above-mentioned vacuuming may not be smoothly performed. In this respect, by providing the tubular light-shielding member (only) in the region near the substrate, it is easier to perform the above-mentioned vacuuming as compared with the case where the tubular light-shielding member is provided in substantially the entire area between the light irradiation unit and the substrate. can do.

The tubular light-shielding member may have a length of half or less of the total length between the light irradiation unit and the substrate. This makes it easier to evacuate the processing chamber.

The light-shielding portion may have a plate-shaped light-shielding member formed in a plate shape. As described above, by using the plate-shaped thin member as the light-shielding member, it is possible to appropriately evacuate the processing chamber without obstructing the exhaust by the vacuum pump in the processing chamber.

The light-shielding portion extends in the traveling direction of the vacuum ultraviolet light and is formed in a tubular shape, and a tubular light-shielding member provided at a position closer to the substrate between the light irradiation portion and the substrate and a plate-shaped light-shielding portion formed in a plate shape. The plate-shaped light-shielding member may be provided below the tubular light-shielding member. By using the tubular light-shielding member and the plate-shaped light-shielding member in combination in this way, the tubular light-shielding member is provided below the tubular light-shielding member while appropriately suppressing the overlap of the irradiation ranges of vacuum ultraviolet light. The irradiation range of vacuum ultraviolet light can be appropriately limited by the plate-shaped light-shielding member. Further, by using the plate-shaped light-shielding member, the length of the tubular light-shielding member can be shortened, the exhaust by the vacuum pump can be appropriately performed, and the vacuum in the processing chamber can be appropriately evacuated.

The plate-shaped light-shielding member may be provided so as to be in contact with the lower end of the tubular light-shielding member. As a result, it is possible to suppress the leakage of vacuum ultraviolet light from between the tubular light-shielding member and the plate-shaped light-shielding member, and it is possible to appropriately suppress the overlap of the irradiation ranges of the vacuum ultraviolet light.

The plate-shaped light-shielding member may have a smaller area for passing light than the tubular light-shielding member when viewed from the traveling direction. Thereby, the irradiation range of the vacuum ultraviolet light can be appropriately limited by the plate-shaped light-shielding member.

The plate-shaped light-shielding member may be provided so as to be separated from the lower end of the tubular light-shielding member. As a result, evacuation by the vacuum pump can be performed more appropriately.

According to the present disclosure, the uniformity of the light irradiation distribution on the irradiation surface of the substrate can be improved.

It is a schematic diagram which shows the substrate processing apparatus of this embodiment. It is a schematic diagram which shows the light irradiation apparatus of the substrate processing apparatus of FIG. It is explanatory drawing which shows the irradiation range of a light irradiation apparatus. It is explanatory drawing of the light irradiation apparatus which concerns on a comparative example. It is a schematic diagram which shows the light irradiation apparatus which concerns on a modification. It is a schematic diagram which shows the light irradiation apparatus which concerns on a modification. It is a schematic diagram which shows the light irradiation apparatus which concerns on a modification. It is a schematic diagram which shows the light irradiation apparatus which concerns on a modification. It is a schematic diagram which shows the light irradiation apparatus which concerns on a modification. It is a schematic diagram which shows the light irradiation apparatus which concerns on a modification. It is explanatory drawing which shows the irradiation range of the light irradiation apparatus which concerns on a modification. It is a schematic diagram which shows the light irradiation apparatus which concerns on a modification. It is a schematic diagram which shows the irradiation part which concerns on the modification. It is a schematic diagram which shows the light irradiation apparatus which concerns on a modification. It is a schematic diagram which shows the light irradiation apparatus which concerns on a modification.

An embodiment of the present invention will be described with reference to the drawings, but the following embodiments are examples for explaining the present invention, and the present invention is not intended to be limited to the following contents. In the description, the same reference numerals will be used for the same elements or elements having the same function, and duplicate description will be omitted.

[Configuration of board processing equipment]
FIG. 1 is a schematic view (longitudinal side view) showing the substrate processing apparatus of the present embodiment. The substrate processing apparatus 1 shown in FIG. 1 is an apparatus that performs a predetermined process on a wafer W (substrate). The wafer W has a disk shape, but a wafer having a shape other than a circle such as a polygon or a part of a circle cut out may be used. The wafer W may be, for example, a semiconductor substrate, a glass substrate, a mask substrate, an FPD (Flat Panel Display) substrate, or various other substrates. In the present embodiment, the substrate processing apparatus 1 will be described as an apparatus for improving the roughness of the surface of the resist pattern formed on the surface of the wafer W by irradiating the wafer W with light. The resist pattern is formed by exposing and developing a resist film formed on the wafer W.

As shown in FIG. 1, the substrate processing device 1 includes a processing container 21, a mounting table 20, a housing 43, and a light irradiation device 4. Note that FIG. 1 shows only a part of the configuration included in the light irradiation device 4.

The processing container 21 is, for example, a vacuum container provided in an atmospheric atmosphere, and is a container for accommodating a wafer W conveyed by a transfer mechanism (not shown). In the substrate processing apparatus 1, the wafer W is processed while the wafer W is housed in the processing container 21. A transport port 22 is formed on the side wall of the processing container 21. The transport port 22 is an opening for loading and unloading the wafer W into and out of the processing container 21. The transport port 22 is opened and closed by the gate valve 23.

The mounting table 20 is a circular table provided in the processing container 21. The mounting table 20 horizontally mounts the wafer W so that the center of the wafer W overlaps the center thereof. For example, three elevating pins (not shown) are provided so as to penetrate the mounting table 20 in the thickness direction (vertical direction). The lower end of the elevating pin is connected to an elevating mechanism (not shown), and the elevating mechanism enables vertical movement (elevation). When the elevating pin is raised by the elevating mechanism, the upper end of the elevating pin reaches above the upper surface of the mounting table 20 and enters the processing container 21 through the transport port 22. Hand over W.

The housing 43 is provided on the upper part of the processing container 21. The housing 43 accommodates a plurality of deuterium lamps 40 (light irradiation units) of the light irradiation device 4. The light irradiation device 4 has a configuration related to irradiation of light on the surface of the wafer W for the purpose of improving the roughness (unevenness) of the surface of the resist pattern. Hereinafter, the details of the light irradiation device 4 will be described with reference to FIGS. 2 and 3.

[Configuration of light irradiation device]
FIG. 2 is a schematic view showing a light irradiation device 4 of the substrate processing device 1 of FIG. FIG. 3 is an explanatory view (a plan view of the irradiation range) showing the irradiation range of the light irradiation device 4. As shown in FIG. 2, the light irradiation device 4 includes a plurality of deuterium lamps 40 (light irradiation unit) and a plurality of polygonal cylinders 50 (cylindrical light-shielding members).

The deuterium lamp 40 irradiates the wafer W with vacuum ultraviolet light having a wavelength of 200 nm or less. More specifically, the deuterium lamp 40 irradiates light having a wavelength of, for example, 115 nm to 400 nm, that is, light having a continuous spectrum of 115 nm to 400 nm. As described above, the light emitted from the deuterium lamp 40 includes vacuum ultraviolet light (VUV light), that is, light having a wavelength of 10 nm to 200 nm. Further, the light emitted from the deuterium lamp 40 includes not only vacuum ultraviolet light (vacuum ultraviolet light) but also near ultraviolet light (near ultraviolet light) having a wavelength larger than 200 nm. The wavelength of the peak of the continuous spectrum of the light emitted from the deuterium lamp 40 of the present embodiment is, for example, 160 nm or less and 150 nm or more.

As described above, since the wavelength range of the spectrum of the light emitted from the deuterium lamp 40 is relatively wide, the resist pattern on the surface of the wafer W receives various light energies, and as a result, on the surface of the resist pattern. Various reactions occur. Specifically, since chemical bonds at various positions in the molecules constituting the resist membrane are cleaved to generate various compounds, the orientation of the molecules existing in the resist membrane before light irradiation is eliminated. As a result, the surface free energy of the resist film is reduced, and the internal stress is reduced. That is, by using the deuterium lamp 40 as the light source, the fluidity of the surface of the resist pattern is increased, and as a result, the effect of improving the roughness of the surface of the wafer W can be improved.

Here, with respect to the light irradiated to the resist film, the larger the wavelength, the easier it is to reach the deep layer of the resist film. In this regard, since the peak wavelength of the spectrum of the light emitted from the deuterium lamp 40 is included in the vacuum ultraviolet light band (10 nm to 200 nm) as described above, the light emitted from the deuterium lamp 40 The intensity of light having a relatively large wavelength is small. Therefore, the light emitted from the deuterium lamp 40 rarely reaches the deep layer of the resist film, and the breakage of the above-mentioned molecular bond can be suppressed in the deep layer of the resist film. That is, by using the deuterium lamp 40 as the light source, the region that reacts by light irradiation in the resist pattern can be limited to the surface side.

The deuterium lamp 40 produces top hat-type light having a flat intensity distribution as compared with the Gaussian-distributed light. Even with top hat type light, the intensity distribution is not completely flat, and the intensity of the light becomes weaker as the distance from the center side (directly below the light source 41) increases. The deuterium lamp 40 irradiates light with a spread emitted from a light source 41 (see FIG. 1) which is a point light source, and specifically, vacuum ultraviolet light having a conical light path with the light source 41 as an apex. Is irradiated toward the wafer W. In this way, the light emitted from the deuterium lamp 40 has a circular irradiation range on the irradiation surface when it is not shielded from light, but a part of the light is shielded by the polygonal cylinder 50 described later. As a result, on the irradiation surface of the wafer W, the irradiation range becomes polygonal (hexagonal in the example of this embodiment) (details will be described later). In addition, in FIGS. 1 and 2 and the like, the outermost optical path among the optical paths of vacuum ultraviolet light is indicated by a alternate long and short dash line.

The light irradiation device 4 includes a plurality of deuterium lamps 40. The deuterium lamps 40 are arranged at predetermined intervals so that the light irradiation distribution on the irradiation surface of the wafer W becomes uniform. For example, as shown in FIG. 3, one deuterium lamp 40 is provided directly above the center of the wafer W, and along the circumference of the disk-shaped wafer W (specifically, slightly inside the circumference). Six deuterium lamps 40 are provided at equal intervals. A shutter (not shown) may be provided between the deuterium lamp 40 and the polygonal cylinder 50. The plurality of deuterium lamps 40 have the same illuminance value of the vacuum ultraviolet light to be irradiated, the ray angle of the vacuum ultraviolet light to be irradiated, and the separation distance from the wafer W.

The polygonal cylinder 50 is a light-shielding portion provided corresponding to each deuterium lamp 40 so as to block the overlap of the irradiation ranges of the vacuum ultraviolet light emitted from the plurality of deuterium lamps 40. The polygonal cylinder 50 removes (absorbs, cuts) the light emitted from the end region of the vacuum ultraviolet light emitted from the deuterium lamp 40, thereby irradiating the vacuum ultraviolet light emitted from the plurality of deuterium lamps 40. It may be the one that blocks the overlap of the above. The fact that the polygonal cylinder 50 is provided corresponding to the deuterium lamp 40 means that the polygonal cylinder 50 has a one-to-one correspondence with the deuterium lamp 40 and is provided directly below the light source 41 of the deuterium lamp 40. That is (see Fig. 3). More specifically, the polygonal cylinder 50 is provided so that the light source 41 is located on the central axis thereof when viewed from the traveling direction of the vacuum ultraviolet light. The polygonal cylinder 50 extends in the traveling direction of the vacuum ultraviolet light over substantially the entire area between the deuterium lamp 40 and the wafer W. The substantially entire area between the deuterium lamp 40 and the wafer W is at least half the total length between the deuterium lamp 40 and the wafer W. Since the polygonal cylinder 50 extends over substantially the entire area between the deuterium lamp 40 and the wafer W, it is possible to appropriately suppress the overlap of the irradiation range with the vacuum ultraviolet light of the other deuterium lamp 40.

The polygonal cylinder 50 is formed in a polygonal shape, specifically, a regular hexagonal shape when viewed from the traveling direction of vacuum ultraviolet light (see FIG. 3). As shown in FIG. 3, the plurality of polygonal cylinders 50 are provided so that adjacent polygonal cylinders 50 are in close contact with each other without a gap when viewed from the traveling direction of vacuum ultraviolet light. More specifically, among the plurality of polygonal cylinders 50, the polygonal cylinder 50 provided corresponding to the deuterium lamp 40 located above the center of the wafer W has a regular hexagon on each side of another polygon. It is provided in contact with the opposite sides of the cylinder 50 (six polygonal cylinders 50 provided corresponding to the deuterium lamps 40 provided at equal intervals along the circumference of the wafer W). Further, among the plurality of polygonal cylinders 50, the six polygonal cylinders 50 provided corresponding to the heavy hydrogen lamps 40 provided at equal intervals along the circumference of the wafer W have one side at the center. The two sides are in contact with the opposite sides of the polygonal cylinder 50, and the two sides are in contact with the adjacent sides of the polygonal cylinders 50 adjacent to each other on the circumference.

Further, the polygonal cylinder 50 extends in the traveling direction of the vacuum ultraviolet light and is formed in a tubular shape (see FIG. 2). The polygonal cylinder 50 may be made of any material as long as it has a low reflectance to vacuum ultraviolet light and a high absorption (cut) rate. The material having a low reflectance means, for example, a material having a reflectance of 90% or less, for example, 60% or less of vacuum ultraviolet light. Specifically, the material of the polygonal cylinder 50 is a material obtained by coating the surface of a base material such as SUS or aluminum with an organic film for reducing reflectance, and for forming an uneven surface on the surface of the above-mentioned base material. Those that have been blasted or roughened can be used. The roughening treatment is, for example, an alumite treatment performed on aluminum as a base material. Considering the vacuum atmosphere, the above-mentioned metal such as SUS or aluminum may be used as a base material, but a low outgas resin material or the like may be used as a base material. The polygonal cylinder 50 extends from directly below the light source 41 to a position close to the irradiation surface of the wafer W. In this way, the polygonal cylinder 50 provided directly below the deuterium lamp 40 extends to a position close to the irradiation surface of the wafer W, so that the vacuum ultraviolet light emitted from each deuterium lamp 40 is a light source. It passes through the corresponding polygonal cylinder 50 from 41 until it reaches the irradiation surface of the wafer W, and the irradiation range in the wafer W is a range corresponding to the shape of the polygonal cylinder 50 (see FIG. 3). As described above, since the plurality of polygonal cylinders 50 are continuous (closely adhered to each other), the irradiation range of the vacuum ultraviolet light passing through the polygonal cylinders 50 adjacent to each other on the wafer W is continuous with each other. There is no overlap (or the overlap range is small).

The shape of the polygonal cylinder 50 may be determined so that a portion (a portion away from the center) where the intensity of the vacuum ultraviolet light emitted from the light source 41 of the deuterium lamp 40 is weak can be shielded. The shape of the polygonal cylinder 50 is determined so that light other than the portion capable of ensuring the intensity of, for example, 70 to 80%, for example, 90% or more of the strongest portion is blocked.

[Action effect]
As described above, the light irradiation device 4 of the substrate processing device 1 according to the present embodiment irradiates the wafer W with vacuum ultraviolet light having a wavelength of 200 nm or less and having a conical optical path with the light source 41 as the apex. A polygonal cylinder 50 provided corresponding to each deuterium lamp 40 so as to block the overlapping portion of the irradiation range of the vacuum ultraviolet light emitted from the plurality of deuterium lamps 40 and the plurality of deuterium lamps 40. The polygonal cylinder 50 is formed in a polygonal shape when viewed from the traveling direction of the vacuum ultraviolet light.

Conventionally, when light is irradiated to the wafer W from a plurality of point light sources having a circular irradiation range on the wafer W, it has been difficult to uniformly irradiate the irradiation surface of the wafer W with light. This will be described with reference to FIGS. 4 (a) and 4 (b), which are explanatory views of the light irradiation device according to the comparative example. FIG. 4A schematically shows a light irradiation device provided with a plurality of deuterium lamps 40. FIG. 4B shows the irradiation intensity of the light irradiation device shown in FIG. 4A. Specifically, the broken line shows the irradiation intensity of each deuterium lamp 40, and the solid line shows the adjacent weights. The total irradiation intensity of the hydrogen lamp 40 is shown. As shown in FIGS. 4A and 4B, when the deuterium lamps 40 are arranged so that the irradiation ranges of the lights do not overlap as much as possible (the central deuterium lamp shown in FIG. 4A). 40 and the deuterium lamp 40 on the right side) have a portion E2 (see FIG. 4B) in which the irradiation intensity of light is weakened because the irradiation range is circular. On the other hand, in order to prevent the occurrence of the portion E2 where the irradiation intensity is weakened, the irradiation ranges of the light emitted from each deuterium lamp 40 are sufficiently overlapped (the central deuterium shown in FIG. 4A). (Refer to the lamp 40 and the deuterium lamp 40 on the left side), and in this case, the problem is that the irradiation intensity of the overlapping portion E1 (see FIG. 4B) becomes extremely strong. As described above, in the conventional configuration in which the wafer W is irradiated with light from a plurality of light sources, it is difficult to uniformly irradiate the irradiation surface of the wafer W with light.

In this regard, in the light irradiation device 4 according to the present embodiment, a plurality of overlapping portions of vacuum ultraviolet light that are irradiated toward the wafer W by taking a conical optical path are provided corresponding to each deuterium lamp 40. It is shielded from light by the polygonal cylinder 50. As a result, the irradiation range of each vacuum ultraviolet light on the wafer W becomes polygonal. Since the irradiation range is not circular as in the comparative example shown in FIG. 4 but has a polygonal shape (specifically, a regular hexagonal shape), the irradiation range of vacuum ultraviolet light passing through the adjacent polygonal cylinders 50 is continuous with each other. It is possible to make them overlap and not to overlap (or reduce the overlap range). That is, according to the light irradiation device 4 of the present embodiment, the uniformity of the light irradiation distribution on the irradiation surface of the wafer W can be improved.

The polygonal cylinder 50 described above extends in the traveling direction of vacuum ultraviolet light and is formed in a tubular shape. Since the polygonal cylinder 50 provided corresponding to the deuterium lamp 40 extends in the height direction (the traveling direction of vacuum ultraviolet light) and is formed in a tubular shape, the deuterium cylinder 50 corresponds to the deuterium. The influence of vacuum ultraviolet light from a deuterium lamp 40 other than the lamp 40 (for example, the adjacent deuterium lamp 40) can be appropriately eliminated. That is, it is possible to appropriately prevent the irradiation range from overlapping with the vacuum ultraviolet light of the other deuterium lamp 40, and to further improve the uniformity of the light irradiation distribution on the irradiation surface of the wafer W.

Further, in the above-mentioned light irradiation device 4, by using the deuterium lamp 40 as the light irradiation unit, in addition to the vacuum ultraviolet light having a wavelength of 200 nm or less, the near ultraviolet light having a wavelength larger than 200 nm is also applied to the wafer W. Can be irradiated. As described above, since the wavelength range of the spectrum of the light emitted from the deuterium lamp 40 is relatively wide, for example, when a resist pattern is formed on the surface of the wafer W, the resist pattern is of light of various wavelengths. You will receive energy. As a result, various reactions occur on the surface of the resist pattern to increase the fluidity, and as a result, the effect of improving the roughness of the surface can be improved.

Further, the deuterium lamp 40 described above generates vacuum ultraviolet light having a wavelength of 160 nm or less. In the deuterium lamp 40, for example, 160 nm or less is the peak wavelength of the continuous spectrum. Therefore, when a resist pattern is formed on the surface of the wafer W by generating vacuum ultraviolet light of 160 nm or less, for example, the surface is formed. The effect of improving the roughness of the surface can be further improved.

[Modification example]
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, as shown in FIG. 5, the illuminance value of the vacuum ultraviolet light emitted from a part of the deuterium lamps 40x among the plurality of light irradiation units is the illuminance of the vacuum ultraviolet light emitted from the other deuterium lamp 40. It may be different from the value. In the example shown in FIG. 5, the illuminance value of the vacuum ultraviolet light emitted from the deuterium lamp 40x is larger than the illuminance value of the vacuum ultraviolet light emitted from the deuterium lamp 40. Further, as shown in FIG. 6, the ray angle of the vacuum ultraviolet light emitted from a part of the deuterium lamps 40y among the plurality of light irradiation units is the ray of the vacuum ultraviolet light emitted from the other deuterium lamp 40. It may be different from the angle. In the example shown in FIG. 6, the ray angle of the vacuum ultraviolet light emitted from the deuterium lamp 40y is made larger than the ray angle of the vacuum ultraviolet light emitted from the deuterium lamp 40. Further, as shown in FIG. 7, even if the separation distance of a part of the deuterium lamp 40z from the wafer W of the plurality of light irradiation units is different from the separation distance of the other deuterium lamp 40 from the wafer W. good. In the example shown in FIG. 7, the separation distance of the deuterium lamp 40z from the wafer W is smaller than the separation distance of the deuterium lamp 40 from the wafer W. In this way, the irradiation distribution can be positively adjusted by making the illuminance value, the light ray angle, or the height (distance from the wafer W) different from each other for the plurality of light irradiation units, and the light irradiation unit can be positively adjusted. It is possible to further improve the uniformity of the light irradiation distribution on the irradiation surface of the wafer W depending on the irradiation condition from the above.

Further, the light irradiation device may further include the separation distance adjusting unit 60 shown in FIG. The separation distance adjusting unit 60 is a mechanism for adjusting the separation distance of the polygonal cylinder 50, which is a light-shielding unit, from the wafer W. Specifically, the separation distance adjusting unit 60 adjusts the separation distance of the polygonal cylinder 50 from the wafer W by raising and lowering the polygonal cylinder 50 according to the control of the controller (not shown). As described above, the polygonal cylinder 50 is configured for the purpose of uniformly irradiating the irradiation surface of the wafer W with light by making the irradiation range polygonal, but by providing the polygonal cylinder 50, It is considered that the shadow of the polygonal cylinder 50 is projected on the irradiation surface of the wafer W, and the shadow does not sufficiently ensure the uniformity of the light irradiation distribution on the irradiation surface of the wafer W. In this regard, the height of the polygonal cylinder 50 (distance from the wafer W) is adjusted by the separation distance adjusting unit 60, so that, for example, the spread of the irradiation light from the adjacent polygonal cylinders 50 to the wafer W is adjusted. It is possible to eliminate the shadowed portion by superimposing the irradiation lights on each other. The height of the polygonal cylinder 50 adjusted by the separation distance adjusting unit 60 is determined by, for example, evaluating in advance the irradiation angle from the deuterium lamp 40, the illuminance of each portion on the wafer W, and the like. ..

Further, the light irradiation device may further include a wafer rotating portion 70 (substrate rotating portion) shown in FIG. The wafer rotating unit 70 is a mechanism for rotating the wafer W with the irradiation surface of the wafer W facing the deuterium lamp 40. Specifically, the wafer rotating portion 70 is connected to the mounting table 20 on which the wafer W is placed via a rotating shaft, and the mounting table is rotated by rotating the rotating shaft according to the control of a controller (not shown). 20 and the wafer W mounted on the mounting table 20 are rotated. Since the irradiation location of the deuterium lamp 40 changes as the wafer W rotates, the uniformity of the light irradiation distribution on the irradiation surface of the wafer W can be further improved. The light irradiation device may rotate the polygonal cylinder 50 and the deuterium lamp 40 with respect to the wafer W instead of the wafer W. Further, the light irradiation device may further include a translation unit for reciprocating the polygonal cylinder 50 or the wafer W in a direction (horizontal direction) parallel to the irradiation surface of the wafer W by about 10 mm. Even in this case, since the irradiation location of the deuterium lamp 40 changes, the uniformity of the light irradiation distribution on the irradiation surface of the wafer W can be further improved. In the mode of reciprocating in the direction parallel to the irradiation surface, unlike the mode of rotating the wafer W, there is an advantage that a portion where the irradiation location does not change (for example, the center of rotation) is unlikely to occur. For example, by rotating a plurality of polygonal cylinders 50 and deuterium lamps 40 with respect to the wafer W and scanning them in parallel directions, a number of deuterium lamps 40 capable of simultaneously irradiating the entire surface of the wafer W can be obtained. Even if it is not provided, the entire surface of the wafer W can be irradiated with vacuum ultraviolet light. When scanning the polygonal cylinder 50 and the deuterium lamp 40 in this way, the number of the polygonal cylinder 50 and the deuterium lamp 40 may be small (for example, one by one).

Further, the light irradiation device may further include a diffusion unit 80 shown in FIG. The diffusion unit 80 is a member that diffuses vacuum ultraviolet light above the polygonal cylinder 50. In the example shown in FIG. 10, the diffusing portion 80 is a mesh-like member and has a function of reflecting and diffusing a part of vacuum ultraviolet light. The diffusion unit 80 may be a rod-shaped member or the like as long as it reflects and diffuses a part of the vacuum ultraviolet light. In the diffusion unit 80, the area of the portion that reflects and diffuses the vacuum ultraviolet light is smaller than the area of the portion that allows the vacuum ultraviolet light to pass downward. Where there is a variation in intensity of the irradiation light due to the internal electrode structure of the light source (lamp), the variation in the irradiation light is averaged by providing the diffuser 80 above the polygonal cylinder 50. The uniformity of the light irradiation distribution on the irradiation surface of the wafer W can be further improved.

Further, the polygonal cylinder 50 has been described as having a regular hexagonal shape when viewed from the traveling direction of the vacuum ultraviolet light, but the present invention is not limited to this. For example, as shown in FIG. 11A, the polygonal cylinder 50x has a rectangular shape. You may. Further, the number of polygonal cylinders 50 is not limited to the example shown in FIG. 3, and for example, as shown in FIG. 11B, a total of 13 polygonal cylinders 50y may be provided.

Further, although it has been described that the light-shielding portion is a polygonal cylinder 50, the present invention is not limited to this, and if the light-shielding portion is formed in a polygonal shape when viewed from the traveling direction of vacuum ultraviolet light, the light-shielding portion is a cylinder extending in the height direction. It does not have to be a shaped member. For example, as shown in FIG. 12, the light-shielding portion may have a mask 200 (plate-shaped light-shielding member) formed in a plate shape. Like the polygonal cylinder 50, the mask 200 is formed in a polygonal shape when viewed from the traveling direction of the vacuum ultraviolet light. Specifically, as shown in FIG. 13A, a hexagonal mask 200a, a square mask 200b, or the like can be used when viewed from the traveling direction of the vacuum ultraviolet light. Unlike the polygonal cylinder 50, the mask 200 has a thin plate shape having a small thickness (thickness in the traveling direction of vacuum ultraviolet light). By providing such a mask 200, the irradiation range of each vacuum ultraviolet light on the wafer W becomes polygonal, and the portion where the light is not irradiated (or the irradiation intensity becomes weak) while preventing the irradiation ranges of the vacuum ultraviolet light from overlapping. Part) can be suppressed. That is, according to the mask 200, the uniformity of the light irradiation distribution on the irradiation surface of the wafer W can be improved. Further, since the mask 200 has a thin plate shape as described above, it is possible to facilitate exhausting by a vacuum pump in the processing chamber as compared with the case where the polygonal cylinder 50 is provided. This makes it possible to more appropriately evacuate the processing chamber.

Further, as shown in FIG. 14, the light-shielding portion extends in the traveling direction of the vacuum ultraviolet light and is formed in a tubular shape, and is positioned closer to the wafer W (that is, a position closer to the lower side) between the deuterium lamp 40 and the wafer W. ) May have a polygonal cylinder 250 and a plate-shaped mask 200. The polygonal cylinder 250 has, for example, a length of less than half of the total length between the deuterium lamp 40 and the wafer W. As described above, the polygonal cylinder 250 is smaller than the polygonal cylinder 50 (see FIG. 2) provided in substantially the entire area between the deuterium lamp 40 and the wafer W, and is provided only in a region close to the wafer W. Has been done. The mask 200 is provided below the polygonal cylinder 250, and more specifically, is provided so as to be in contact with the lower end of the polygonal cylinder 250. The mask 200 may be provided as close to the wafer W as possible from the viewpoint of limiting the light irradiation range, but is separated from the wafer W by a distance (for example, 30 mm) that enables the transfer of the wafer W by the arm. doing. The size of the region through which the light passes through the mask 200 is smaller than that of the polygonal cylinder 250 when viewed from the traveling direction of the vacuum ultraviolet light. Thereby, the irradiation range of the vacuum ultraviolet light can be appropriately limited by the mask 200.

Here, the basic configuration of the substrate processing apparatus of FIG. 14 will also be described. As shown in FIG. 14, the substrate processing apparatus includes a processing chamber 210 and a light source chamber 212. The processing chamber 210 includes a housing 214, a rotation holding portion 216, a gate valve 218, and a vacuum pump 222. The housing 214 is, for example, a part of a vacuum container provided in an atmospheric atmosphere, and is configured to be capable of accommodating a wafer W conveyed by a transfer mechanism (not shown). The housing 214 presents with a bottomed tubular body that is open upward. Through holes 214a and 214c are provided on the wall surface of the housing 214.

The rotation holding portion 216 has a rotating portion 216a, a shaft 216b, and a holding portion 216c. The rotating unit 216a operates based on an operation signal from a controller (not shown) to rotate the shaft 216b. The rotating portion 216a is a power source for, for example, an electric motor. The holding portion 216c is provided at the tip end portion of the shaft 216b. The holding portion 216c can hold the wafer W in a state where the posture of the wafer W is substantially horizontal. When the rotating portion 216a rotates with the wafer W placed on the holding portion 216c, the wafer W rotates around an axis (rotation axis) perpendicular to the surface thereof.

The gate valve 218 is arranged on the outer surface of the side wall of the housing 214. The gate valve 218 operates according to the instruction of the controller (not shown), and is configured to close and open the through hole 214a of the housing 214. When the through hole 214a is opened by the gate valve 218, the wafer W can be carried in and out of the housing 214. That is, the through hole 214a also functions as an entrance / exit of the wafer W.

The vacuum pump 222 is configured to discharge gas from the inside of the housing 214 to bring the inside of the housing 214 into a vacuum state (low oxygen state).

The light source chamber 212 includes a housing 224, a partition wall 226, a shutter member 228, and a plurality of deuterium lamps 40.

The housing 224 is, for example, a part of a vacuum vessel provided in the atmosphere. The housing 224 presents with a bottomed tubular body that is open downward. The housing 224 is arranged so that the open end of the housing 224 faces the open end of the housing 214.

The partition wall 226 is arranged between the housings 214 and 224, and is configured to partition the space inside the housing 214 from the space inside the housing 224. In other words, the partition wall 226 functions as a top wall of the housing 214 and also as a bottom wall of the housing 224. That is, the housing 224 is arranged so as to be adjacent to the housing 214 in the direction perpendicular to the surface of the wafer W. The space V in the housing 224 after being partitioned by the partition wall 226 is a flat space whose height in the vertical direction is smaller than its size in the horizontal direction.

The partition wall 226 is provided with a plurality of through holes 226a. The plurality of through holes 226a are arranged so as to overlap the shutter member 228 in the vertical direction. Each of the plurality of through holes 226a is closed by a window member capable of transmitting vacuum ultraviolet light. The window member may be, for example, glass (for example, magnesium fluoride glass).

The shutter member 228 is arranged in the space V, and is configured to block and pass the vacuum ultraviolet light emitted by the deuterium lamp 40. The shutter member 228 has, for example, a disk shape. The shutter member 228 is provided with a plurality of through holes.

By using the polygonal cylinder 250 and the mask 200 as described above in combination, the mask provided below the polygonal cylinder 250 is appropriately suppressed from overlapping the irradiation ranges of the vacuum ultraviolet light by the polygonal cylinder 250. The irradiation range of vacuum ultraviolet light can be appropriately limited by 200. Further, by using the mask 200, the length of the polygonal cylinder 250 can be shortened, the exhaust by the vacuum pump 222 can be appropriately performed, and the vacuum in the processing chamber 210 can be appropriately evacuated. Further, since the mask 200 is provided so as to be in contact with the lower end of the polygonal cylinder 250, it is possible to suppress leakage of vacuum ultraviolet light between the polygonal cylinder 250 and the mask 200, and the irradiation range of the vacuum ultraviolet light. Can be appropriately suppressed from overlapping. The light-shielding portion may be formed only by the small polygonal cylinder 250 provided below (that is, without the mask 200).

As shown in FIG. 15, the mask 200 may be provided so as to be separated from the lower end of the polygonal cylinder 250. This makes it easier to evacuate by the vacuum pump 222, and evacuate by the vacuum pump 222 can be performed more appropriately. In the configuration of FIG. 15, the size of the light-transmitting region of the mask 200 and the polygonal cylinder 50 may be about the same when viewed from the traveling direction of the vacuum ultraviolet light. From the viewpoint of facilitating evacuation, the polygonal cylinder 50 may be provided with one or more holes.

4 ... Light irradiation device, 40, 40x, 40y, 40z ... Deuterium lamp (light irradiation unit), 41 ... Light source, 50, 50x, 50y ... Polygonal cylinder (light-shielding part, tubular light-shielding member), 60 ... Separation distance Adjusting unit, 70 ... Wafer rotating part (board rotating part), 80 ... Diffusing part, 200 ... Mask (light-shielding part, plate-shaped light-shielding member), W ... Wafer.

Claims (19)

A plurality of light irradiation units that irradiate a substrate on which a resist pattern is formed with vacuum ultraviolet light having a conical optical path with a light source as the apex.
A light-shielding unit provided corresponding to each light-irradiating unit is provided so as to block the overlapping portion of the irradiation range of the vacuum ultraviolet light emitted from the plurality of light-irradiating units.
The light-shielding portion is a light irradiation device formed in a polygonal shape when viewed from the traveling direction of the vacuum ultraviolet light. The light irradiation device according to claim 1, wherein the light-shielding portion has a tubular light-shielding member that extends in the traveling direction of the vacuum ultraviolet light and is formed in a tubular shape. The light irradiation device according to claim 2, wherein the tubular light-shielding member extends in the traveling direction over substantially the entire area between the light irradiation unit and the substrate. The light irradiation device according to claim 2, wherein the tubular light-shielding member is provided at a position closer to the substrate between the light irradiation unit and the substrate. The light irradiation device according to claim 4, wherein the tubular light-shielding member has a length of half or less of the total length between the light irradiation unit and the substrate. The light irradiation device according to any one of claims 1 to 5, wherein the light-shielding portion has a plate-shaped light-shielding member formed in a plate shape. The light-shielding portion is formed in a tubular shape extending in the traveling direction of the vacuum ultraviolet light, and is formed in a plate shape with a tubular light-shielding member provided at a position closer to the substrate between the light irradiation portion and the substrate. It has a plate-shaped light-shielding member
The light irradiation device according to claim 1, wherein the plate-shaped light-shielding member is provided below the tubular light-shielding member. The light irradiation device according to claim 7, wherein the plate-shaped light-shielding member is provided so as to be in contact with the lower end of the tubular light-shielding member. The light irradiation device according to claim 8, wherein the plate-shaped light-shielding member has a smaller area for passing light than the tubular light-shielding member when viewed from the traveling direction. The light irradiation device according to claim 7, wherein the plate-shaped light-shielding member is provided so as to be separated from the lower end of the tubular light-shielding member. The light irradiation device according to any one of claims 1 to 10, further comprising a separation distance adjusting unit for adjusting the separation distance of the light-shielding unit from the substrate. The light irradiation device according to any one of claims 1 to 11, wherein the light irradiation unit includes a deuterium lamp. The light irradiation device according to claim 12, wherein the deuterium lamp generates vacuum ultraviolet light having a wavelength of 200 nm or less. The light irradiation device according to claim 13, wherein the deuterium lamp generates vacuum ultraviolet light having a wavelength of 160 nm or less. Any one of claims 1 to 14, wherein at least one of the illuminance value of the vacuum ultraviolet light to be irradiated, the light ray angle of the vacuum ultraviolet light to be irradiated, and the separation distance from the substrate is different from each other. The light irradiation device according to item 1. The light irradiation device according to any one of claims 1 to 15, further comprising a diffusing portion for diffusing the vacuum ultraviolet light above the shading portion. The light irradiation device according to any one of claims 1 to 16, further comprising a substrate rotating portion for rotating the substrate with the irradiation surface of the substrate facing the light irradiation portion. The light irradiation device according to any one of claims 1 to 17, further comprising a parallel moving portion for reciprocating the light-shielding portion or the substrate in a direction parallel to the irradiation surface of the substrate. The light irradiation device according to any one of claims 1 to 18, wherein the light-shielding portion is made of a material having a reflectance of vacuum ultraviolet light of 90% or less.

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