KR102667236B1 - light irradiation device - Google Patents

Abstract

The light irradiation device includes a plurality of deuterium lamps for irradiating vacuum ultraviolet light having a wavelength of 200 nm or less and taking a conical optical path with the light source as the vertex toward the wafer W, and vacuum ultraviolet light irradiated from the plurality of deuterium lamps. A polygonal cylinder is provided corresponding to each deuterium lamp to shield the overlapping portion of the irradiation range from light, and the polygonal cylinder is formed into a polygonal shape when viewed from the direction in which the vacuum ultraviolet light travels.

Description

light irradiation device

This disclosure relates to a light irradiation device that irradiates light to a substrate.

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

Japanese Patent No. 3342856 Publication

When carrying out the above-described process of irradiating light to a substrate with a diameter of about 300 mm, a plurality of lamps are placed on the substrate from the viewpoint of ensuring 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 each lamp is arranged so that the irradiation ranges of each lamp do not overlap, parts where light is not irradiated (or the irradiation intensity is weakened) will occur. On the other hand, in order to prevent areas where the irradiation intensity is weakened, it is necessary to overlap part of the irradiation range of each lamp, and in this case, the problem is that the irradiation intensity in the overlapping area becomes extremely strong. As described above, in a configuration in which light is irradiated to a substrate by a plurality of lamps, it is difficult to uniformly irradiate light to the irradiated surface of the substrate.

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

A light irradiation device according to an aspect of the present disclosure includes a plurality of light irradiation units that irradiate vacuum ultraviolet light taking a cone-shaped optical path with a light source as the vertex toward a substrate, and an irradiation range of the vacuum ultraviolet light irradiated from the plurality of light irradiation units. A light-shielding portion provided corresponding to each light irradiation portion is provided to shield the overlapping portion from light, and the light-shielding portion is formed in a polygonal shape when viewed from the direction in which the vacuum ultraviolet light travels.

In the light irradiation device of the present disclosure, overlapping portions of a plurality of vacuum ultraviolet lights irradiated toward the substrate along a conical optical path are shielded by polygonal light-shielding portions provided corresponding to each light irradiation portion. Here, when light is irradiated to the substrate from a plurality of point light sources whose irradiation ranges on the substrate are circular, if each point light source is arranged so that the irradiation ranges of each light do not overlap, the light is not irradiated because the irradiation ranges are circular. Parts (or parts where the irradiation intensity is weakened) occur. On the other hand, in order to prevent the occurrence of areas where light is not irradiated (or areas where the irradiation intensity is weakened), it is necessary to overlap part of the irradiation range of the light irradiated from each point light source, and in this case, the irradiation intensity of the overlapping area is Becoming extremely strong becomes a problem. In this way, in the conventional configuration in which light is irradiated from a plurality of light sources to a substrate, it has been difficult to uniformly irradiate light to the irradiated surface of the substrate. In this regard, in the light irradiation device of the present disclosure, a light-shielding portion that blocks overlapping portions of a plurality of vacuum ultraviolet lights is formed in a polygonal shape when viewed from the direction in which the vacuum ultraviolet light travels. As a result, the irradiation range of each vacuum ultraviolet light on the substrate becomes polygonal. From this perspective, unlike the case where the irradiation range is circular, the occurrence of areas where light is not irradiated (or areas where the irradiation intensity is weakened) can be suppressed while preventing the irradiation ranges from overlapping. That is, according to the light irradiation device of the present disclosure, the uniformity of light irradiation distribution on the irradiation surface of the substrate can be improved.

The light-shielding portion may have a cylindrical light-shielding member extending in the direction of travel of vacuum ultraviolet light and formed into a cylindrical shape. The light-shielding portion provided corresponding to the light irradiation portion extends in the height direction (direction of travel of vacuum ultraviolet light) and is formed in a cylindrical shape, thereby preventing the light-shielding portion from receiving vacuum from a light irradiation portion other than the corresponding light irradiation portion (for example, an adjacent light irradiation portion). The influence of ultraviolet light can be appropriately excluded. That is, by appropriately preventing the irradiation range from overlapping with the vacuum ultraviolet light of other light irradiation parts, the uniformity of light irradiation distribution on the irradiation surface of the substrate can be further improved.

It may further include a distance adjusting part that adjusts the distance between the light shielding part and the substrate. When a light-shielding portion (particularly a cylindrical light-shielding portion) is provided, the shadow of the light-shielding portion is projected onto the irradiated surface of the substrate, and there is a risk that the uniformity of light irradiation distribution on the irradiated surface of the substrate may deteriorate due to the shadow. there is. In this regard, by adjusting the height of the light-shielding portion (separation distance from the substrate) by the separation distance adjustment portion, for example, the diffusion of the irradiated light from the adjacent light-shielding portion to the substrate can be adjusted, allowing the irradiated light to overlap each other, etc. You can eliminate the part that is in shadow.

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 with a wavelength greater than 200 nm in addition to vacuum ultraviolet light with a wavelength of 200 nm or less. In this way, since the spectral wavelength range of the light irradiated from the deuterium lamp is relatively wide, for example, when a resist pattern is formed on the surface of a substrate, the resist pattern receives light energy of various wavelengths. As a result, various reactions occur on the surface of the resist pattern, thereby increasing fluidity, and as a result, the effect of improving the surface roughness can be improved.

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

The plurality of light irradiation units may differ from each other in at least one of the illuminance value of the irradiated vacuum ultraviolet light, the beam angle of the irradiated vacuum ultraviolet light, and the separation distance from the substrate. In this way, by varying the illuminance value, beam angle, or height of the light irradiation portion (separation distance from the substrate) for a plurality of light irradiation portions, the irradiation distribution can be actively adjusted, and the irradiation of the substrate can be adjusted according to the irradiation situation. The uniformity of light irradiation distribution on the surface can be further improved.

Above the light-shielding portion, a diffusion portion that diffuses vacuum ultraviolet light may be further provided. Irradiated light originates from the internal electrode structure of the light source (lamp), so there is variation in intensity. In this regard, by providing a diffusion portion above the light-shielding portion, fluctuations in irradiated light are averaged, and the uniformity of light irradiation distribution on the irradiated surface of the substrate can be further improved.

A substrate rotation unit that rotates the substrate while the irradiation surface of the substrate is opposed to the light irradiation unit may be further provided. As a result, since the irradiation location changes, the uniformity of light irradiation distribution on the irradiation surface can be further improved.

It may further include a parallel moving part that reciprocates the light blocking part or the substrate in a direction parallel to the irradiation surface of the substrate. In this case as well, since the irradiation location changes, the uniformity of light irradiation distribution on the irradiation surface can be further improved. Additionally, in the mode of reciprocating in a direction parallel to the irradiation surface, unlike the mode of rotating the substrate, it is difficult to generate a portion (for example, center of rotation) where the irradiation location does not change. Additionally, the light-shielding portion may be made of a material with a reflectance of vacuum ultraviolet light of 90% or less.

The cylindrical light blocking member may extend in the direction of travel over approximately the entire area between the light irradiation portion and the substrate. As a result, it is possible to more appropriately suppress the irradiation range from overlapping with the vacuum ultraviolet light of other light irradiation parts.

The cylindrical light blocking member may be provided at a position near the substrate between the light irradiation unit and the substrate. When using vacuum ultraviolet light, it is necessary to apply vacuum using a vacuum pump to bring the inside of the treatment chamber into a hypoxic state. If a cylindrical light blocking member is provided in approximately the entire area between the light irradiation unit and the substrate, it becomes difficult to exhaust the processing chamber using a vacuum pump, and there is a risk that the above-mentioned vacuum suction may not be performed smoothly. In this regard, by providing the cylindrical light blocking member (only) in the area near the substrate, it is possible to easily perform the above-mentioned vacuum suction compared to the case where the cylindrical light blocking member is provided in approximately the entire area between the light irradiation portion and the substrate.

The cylindrical light blocking member may be less than half the total length between the light irradiation portion and the substrate. Thereby, vacuum suction within the processing chamber can be performed more easily.

The light-shielding portion may have a plate-shaped light-shielding member formed in a plate shape. In this way, by using a member with a thin plate shape as a light blocking member, it is possible to properly vacuum the inside of the processing chamber without impeding exhaustion by the vacuum pump within the processing chamber.

The light-shielding portion extends in the direction of travel of vacuum ultraviolet light and is formed in a cylindrical shape, and has a cylindrical light-shielding member provided at a position near the substrate between the light irradiation portion and the substrate, and a plate-shaped light-shielding member formed in a plate shape, wherein the plate-shaped light-shielding member is a cylindrical light-shielding member. It may be provided below the member. By using the cylindrical light-shielding member and the plate-shaped light-shielding member in combination in this way, the overlapping of the irradiation ranges of the vacuum ultraviolet light by the cylindrical light-shielding member is appropriately suppressed, and the vacuum ultraviolet light is irradiated by the plate-shaped light-shielding member provided below the cylindrical light-shielding member. The scope of investigation can be appropriately limited. Additionally, by using a plate-shaped light blocking member, the length of the cylindrical light blocking member can be shortened, and exhaustion by a vacuum pump can be properly performed to properly vacuum the processing chamber.

The plate-shaped light blocking member may be provided so as to contact the lower end of the cylindrical light blocking member. As a result, leakage of vacuum ultraviolet light can be suppressed between the cylindrical light blocking member and the plate-shaped light blocking member, and overlap of irradiation ranges of vacuum ultraviolet light can be appropriately suppressed.

When viewed from the direction of travel, the plate-shaped light blocking member may have a smaller area through which light passes than the cylindrical light blocking member. As a result, the irradiation range of vacuum ultraviolet light can be appropriately limited by the plate-shaped light blocking member.

The plate-shaped light blocking member may be provided to be spaced apart from the lower end of the cylindrical light blocking member. Thereby, vacuum suction by the vacuum pump can be performed more appropriately.

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

1 is a schematic diagram showing a substrate processing apparatus of this embodiment.
FIG. 2 is a schematic diagram showing the light irradiation device of the substrate processing device of FIG. 1.
Figure 3 is an explanatory diagram showing the irradiation range of the light irradiation device.
Figure 4 is an explanatory diagram of a light irradiation device according to a comparative example.
Figure 5 is a schematic diagram showing a light irradiation device according to a modified example.
Figure 6 is a schematic diagram showing a light irradiation device according to a modified example.
Figure 7 is a schematic diagram showing a light irradiation device according to a modified example.
Figure 8 is a schematic diagram showing a light irradiation device according to a modified example.
Figure 9 is a schematic diagram showing a light irradiation device according to a modified example.
Figure 10 is a schematic diagram showing a light irradiation device according to a modified example.
Figure 11 is an explanatory diagram showing the irradiation range of the light irradiation device according to the modified example.
Figure 12 is a schematic diagram showing a light irradiation device according to a modified example.
Figure 13 is a schematic diagram showing an irradiation unit according to a modification.
Figure 14 is a schematic diagram showing a light irradiation device according to a modified example.
Figure 15 is a schematic diagram showing a light irradiation device according to a modified example.

Embodiments of the present invention will be described with reference to the drawings. However, the following embodiments are examples for illustrating the present invention and are not intended to limit the present invention to the following contents. In the description, the same symbols are used for the same elements or elements with the same function, and overlapping descriptions are omitted.

[Configuration of substrate processing device]

1 is a schematic diagram (longitudinal side view) showing the substrate processing apparatus of this 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 with a portion of the circle cut out or a shape other than a circle, such as a polygon, 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 other various substrates. In this embodiment, the substrate processing apparatus 1 is described as an apparatus that improves the surface roughness of a resist pattern formed on the surface of the wafer W by irradiating light to the wafer W. Additionally, the resist pattern is formed by exposing and developing the resist film formed on the wafer W.

As shown in FIG. 1 , the substrate processing apparatus 1 includes a processing container 21, a loading table 20, a housing 43, and a light irradiation device 4. In addition, in FIG. 1, only a part of the structure included in the light irradiation device 4 is shown.

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

The loading table 20 is a circular table provided within the processing container 21. The stacking table 20 stacks the wafer W horizontally with the center of the wafer W overlapping with the center thereof. For example, three lifting pins (not shown) are provided to penetrate the loading table 20 in the thickness direction (vertical direction). The lower end of the lifting pin is connected to a lifting mechanism (not shown), and can be moved (elevated) in the vertical direction by the lifting mechanism. The lifting pin is a conveyance mechanism (not shown) that, in a state raised by the elevation mechanism, has its upper end reaching above the upper surface of the loading table 20 and enters the processing container 21 through the conveyance port 22. The wafer W is transferred between .

The housing 43 is provided at the upper part of the processing container 21. The housing 43 accommodates a plurality of deuterium lamps 40 (light irradiation portion) of the light irradiation device 4. The light irradiation device 4 is configured to irradiate light to the surface of the wafer W for the purpose of improving the surface roughness (irregularities) of the resist pattern. Hereinafter, 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 diagram showing the light irradiation device 4 of the substrate processing device 1 in FIG. 1. FIG. 3 is an explanatory diagram showing the irradiation range of the light irradiation device 4 (a diagram of the irradiation range viewed in a plan view). As shown in FIG. 2, the light irradiation device 4 is provided with a plurality of deuterium lamps 40 (light irradiation portion) and a plurality of polygonal cylinders 50 (cylindrical light-shielding members).

The deuterium lamp 40 irradiates vacuum ultraviolet light with a wavelength of 200 nm or less toward the wafer W. More specifically, the deuterium lamp 40 irradiates light with a wavelength of, for example, 115 nm to 400 nm, that is, light forming 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 with a wavelength of 10 nm to 200 nm. In addition, the light irradiated from the deuterium lamp 40 includes not only vacuum ultraviolet light (vacuum ultraviolet light) but also near-ultraviolet light (near-ultraviolet light) whose wavelength is greater than 200 nm. The wavelength of the continuous spectrum peak of the light irradiated from the deuterium lamp 40 of this embodiment is, for example, 160 nm or less and 150 nm or more.

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

Here, for 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 wavelength of the spectral peak of the light irradiated from the deuterium lamp 40 is included in the band (10 nm to 200 nm) of vacuum ultraviolet light as described above, the light irradiated from the deuterium lamp 40 In contrast, the intensity of light with a relatively large wavelength is small. For this reason, less light irradiated from the deuterium lamp 40 reaches the deeper layer of the resist film, and cleavage of the molecular bonds in the deeper layer of the resist film can be suppressed. That is, by using the deuterium lamp 40 as a light source, the area in the resist pattern that reacts to light irradiation can be limited to the surface side.

The deuterium lamp 40 generates top hat-shaped light with a monotonous intensity distribution compared to Gaussian-distributed light. Furthermore, even with top hat-shaped light, the intensity distribution is not completely monotonous, and the intensity of the light becomes weaker as it moves away from the center (right below the light source 41). The deuterium lamp 40 irradiates diffused light emitted from the light source 41 (see FIG. 1), which is a point light source, and is specifically a vacuum element that takes a cone-shaped optical path with the light source 41 as the vertex. External light is irradiated toward the wafer W. In this way, when the light emitted from the deuterium lamp 40 is not shielded, the irradiation area is circular on the irradiation surface, but a part of the light is blocked by the polygonal cylinder 50, which will be described later, so that the wafer ( In the irradiation surface W), the irradiation area has a polygonal shape (hexagonal shape in the example of this embodiment) (details will be described later). Additionally, in Figures 1 and 2, the outermost optical path of the vacuum ultraviolet light is shown with a dashed-dotted line.

The light irradiation device 4 is equipped with a plurality of deuterium lamps 40. Each deuterium lamp 40 is arranged at predetermined intervals so that the light irradiation distribution on the irradiation surface of the wafer W is uniform. For example, as shown in FIG. 3, one deuterium lamp 40 is provided right above the center of the wafer W, and on the circumference of the disk-shaped wafer W (specifically, slightly inside the circumference). Six deuterium lamps 40 are provided at equal intervals along the line. Additionally, a shutter (not shown) may be provided between the deuterium lamp 40 and the polygonal cylinder 50. In addition, the plurality of deuterium lamps 40 have the same illuminance value of the vacuum ultraviolet light irradiated, the beam angle of the irradiated vacuum ultraviolet light, 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 overlapping irradiation ranges of the vacuum ultraviolet light irradiated from the plurality of deuterium lamps 40. The polygonal cylinder 50 removes (absorbs, cuts) the emission of the end region of the vacuum ultraviolet light irradiated from the deuterium lamps 40, thereby ensuring that the irradiation ranges of the vacuum ultraviolet light irradiated from the plurality of deuterium lamps 40 overlap. It may be to shade the light. The fact that the polygonal cylinder 50 is provided to correspond to the deuterium lamp 40 means that the polygonal cylinder 50 corresponds one to one to the deuterium lamp 40 and is located directly below the light source 41 of the deuterium lamp 40. This means that it is provided (see Figure 3). More specifically, the polygonal cylinder 50 is provided so that the light source 41 is located on its central axis when viewed from the direction in which vacuum ultraviolet light travels. The polygonal tube 50 extends in the direction in which the vacuum ultraviolet light travels, covering approximately the entire area between the deuterium lamp 40 and the wafer W. Approximately the entire length between the deuterium lamp 40 and the wafer W is at least half of the total length between the deuterium lamp 40 and the wafer W. Since the polygonal tube 50 extends approximately over the entire area between the deuterium lamp 40 and the wafer W, overlap of the irradiation range with the vacuum ultraviolet light of other deuterium lamps 40 can be appropriately suppressed. .

The polygonal cylinder 50 is formed into a polygonal shape, specifically a regular hexagon shape, when viewed from the direction in which the vacuum ultraviolet light travels (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 any gap when viewed from the direction in which vacuum ultraviolet light travels. 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 is a polygonal cylinder 50 with each side of a regular hexagon having different sides. It is provided in contact with opposing sides of (six polygonal cylinders 50 provided in response to deuterium lamps 40 provided at equal intervals along the circumference of the wafer W). In addition, among the plurality of polygonal cylinders 50, six polygonal cylinders 50 provided corresponding to the deuterium lamps 40 provided at equal intervals along the circumference of the wafer W, one side of which is a polygonal cylinder 50 in the center. ) is in contact with the opposing side, and two sides are in contact with the adjacent side of the polygonal cylinder 50 adjacent to the circumference.

Additionally, the polygonal cylinder 50 extends in the direction of travel of vacuum ultraviolet light and is formed in a cylindrical shape (see Fig. 2). The polygonal tube 50 may be made of any material as long as it has a low reflectance and high absorption (cut) coefficient for vacuum ultraviolet light. A material with a low reflectance refers to a material with a reflectance of vacuum ultraviolet light of 90% or less, for example, 60% or less. Specifically, the material of the polygonal cylinder 50 is one in which an organic film that reduces reflectance is applied to the surface of a base material such as SUS or aluminum, blasting treatment to form an uneven surface on the surface of the above-mentioned base material, and roughening treatment. You can use what has been done. In addition, the roughening treatment is, for example, an alumite treatment performed on aluminum, which is a base material. Considering that it is a vacuum atmosphere, the above-mentioned metal such as SUS or aluminum may be used as the base material, but a low outgassing resin material, etc. may be used as the base material. The polygonal tube 50 extends from immediately below the light source 41 to a position close to the irradiation surface of the wafer W. In this way, the polygonal tube 50 provided immediately below the deuterium lamp 40 extends to a position close to the irradiation surface of the wafer W, so that the vacuum ultraviolet light irradiated from each deuterium lamp 40 is, From the light source 41 until it reaches the irradiation surface of the wafer W, it passes through the corresponding polygonal cylinder 50, and the irradiation range on the wafer W is determined by the shape of the polygonal cylinder 50 (Figure (Refer to 3). As described above, since the plurality of polygonal cylinders 50 are continuous (closely adhered to each other without gaps), the irradiation range of the vacuum ultraviolet light passing through the adjacent polygonal cylinders 50 to the wafer W is They are continuous with each other and do not overlap (or, the overlap range is small).

Additionally, the shape of the polygonal cylinder 50 may be determined so that a portion (a portion distant 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 shaded. The shape of the polygonal tube 50 is determined so that, for example, 70 to 80% of the strongest portion, for example, 90% or more of the intensity is blocked, light is blocked.

[Action effect]

As described above, the light irradiation device 4 of the substrate processing apparatus 1 according to the present embodiment radiates vacuum ultraviolet light having a wavelength of 200 nm or less and taking a conical optical path with the light source 41 as the vertex to the wafer ( A plurality of deuterium lamps 40 irradiating toward W) and a polygonal cylinder provided corresponding to each deuterium lamp 40 to block the overlapping portion of the irradiation range of the vacuum ultraviolet light irradiated from the plurality of deuterium lamps 40. Equipped with 50, the polygonal cylinder 50 is formed in a polygonal shape when viewed from the direction in which vacuum ultraviolet light travels.

Conventionally, when light is irradiated to the wafer W from a plurality of point light sources with circular irradiation ranges on the wafer W, it has been difficult to uniformly irradiate light to the irradiation surface of the wafer W. This point will be explained with reference to FIGS. 4(a) and 4(b), which are explanatory diagrams of the light irradiation device according to the comparative example. Figure 4(a) schematically shows a light irradiation device provided with a plurality of deuterium lamps 40. Figure 4(b) shows the irradiation intensity of the light irradiation device shown in Figure 4(a). Specifically, the broken line indicates the irradiation intensity of each deuterium lamp 40, and the solid line indicates the irradiation intensity of the adjacent deuterium lamp 40. The total irradiation intensity of the deuterium lamp 40 is shown. As shown in Figure 4 (a) and Figure 4 (b), when the deuterium lamp 40 is arranged so that the irradiation range of each light does not overlap as much as possible (the central deuterium lamp shown in Figure 4 (a) (40) and the deuterium lamp 40 on the right), since the irradiation range is circular, a portion E2 (see Fig. 4(b)) where the irradiation intensity of light is weakened occurs. On the other hand, in order to prevent the occurrence of the portion E2 where the irradiation intensity is weakened, the irradiation range of the light irradiated from each point deuterium lamp 40 must sufficiently overlap (the central deuterium lamp 40 shown in (a) of FIG. 4 and (see deuterium lamp 40 on the left), and in this case, the problem is that the irradiation intensity of the overlapping portion E1 (see (b) in FIG. 4) becomes extremely strong. In this way, in the conventional configuration in which light is irradiated from a plurality of light sources to the wafer W, it has been difficult to uniformly irradiate light to the irradiation surface of the wafer W.

In this regard, in the light irradiation device 4 according to the present embodiment, the overlapping portion of the plurality of vacuum ultraviolet lights irradiated toward the wafer W by taking a conical optical path is a polygon provided corresponding to each deuterium lamp 40. It is shaded from light by the barrel 50. As a result, the irradiation range of each vacuum ultraviolet light on the wafer W becomes polygonal. The irradiation range is not circular as in the comparative example shown in FIG. 4, but is polygonal (specifically, regular hexagonal), thereby making the irradiation ranges of vacuum ultraviolet light that passed through adjacent polygonal cylinders 50 continuous with each other. It becomes possible to avoid duplication (or reduce the duplication range). That is, according to the light irradiation device 4 of this embodiment, the uniformity of light irradiation distribution on the irradiation surface of the wafer W can be improved.

The polygonal cylinder 50 described above extends in the direction of travel of vacuum ultraviolet light and is formed in a cylindrical shape. The polygonal cylinder 50 provided corresponding to the deuterium lamp 40 extends in the height direction (direction of travel of vacuum ultraviolet light) and is formed in a cylindrical shape, so that the polygonal cylinder 50 is used in addition to the corresponding deuterium lamp 40. The influence of vacuum ultraviolet light from the deuterium lamp 40 (for example, an adjacent deuterium lamp 40) can be appropriately excluded. That is, by appropriately preventing the irradiation range from overlapping with the vacuum ultraviolet light of other deuterium lamps 40, the uniformity of light irradiation distribution on the irradiation surface of the wafer W can be further improved.

In addition, the above-described light irradiation device 4 uses the deuterium lamp 40 as a light irradiation unit, thereby irradiating the wafer W not only to vacuum ultraviolet light with a wavelength of 200 nm or less, but also to near-ultraviolet light with a wavelength greater than 200 nm. can be investigated. In this way, since the spectral wavelength range of the light irradiated 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 emits light energy of various wavelengths. You will receive it. As a result, various reactions occur on the surface of the resist pattern, thereby increasing fluidity, and as a result, the effect of improving the surface roughness can be improved.

Additionally, the deuterium lamp 40 described above generates vacuum ultraviolet light with 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, so by generating vacuum ultraviolet light of 160 nm or less, for example, a resist pattern is formed on the surface of the wafer W. In some cases, the effect of improving surface roughness can be further improved.

[Variation 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 vacuum ultraviolet light irradiated from some of the deuterium lamps 40x among the plurality of light irradiation units is the illuminance value of the vacuum ultraviolet light irradiated from other deuterium lamps 40. It may be different from In the example shown in FIG. 5, the illuminance value of the vacuum ultraviolet light emitted from the deuterium lamp 40x is greater than the illuminance value of the vacuum ultraviolet light emitted from the deuterium lamp 40. In addition, as shown in FIG. 6, even if the ray angle of the vacuum ultraviolet light irradiated from some of the deuterium lamps 40y among the plurality of light irradiation units is different from the ray angle of the vacuum ultraviolet light irradiated from other deuterium lamps 40 do. In the example shown in FIG. 6, the beam angle of the vacuum ultraviolet light emitted from the deuterium lamp 40y is larger than the beam angle of the vacuum ultraviolet light emitted from the deuterium lamp 40. Additionally, as shown in FIG. 7, the separation distance from the wafer W of some of the deuterium lamps 40z among the plurality of light irradiation units may be different from the separation distance from the wafer W of other deuterium lamps 40. 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, by varying the illuminance value, beam angle, or height (separation distance from the wafer W) for a plurality of light irradiation units, the irradiation distribution can be actively adjusted, depending on the irradiation situation from the light irradiation unit, The uniformity of light irradiation distribution on the irradiation surface of the wafer W can be further improved.

Additionally, the light irradiation device may further include a separation distance adjusting unit 60 shown in FIG. 8. The separation distance adjusting unit 60 is a mechanism that adjusts the separation distance between the polygonal cylinder 50, which is a light blocking unit, and 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 under the control of a controller (not shown). As described above, the polygonal cylinder 50 is designed to uniformly irradiate light onto the irradiation surface of the wafer W by making the irradiation area polygonal. However, by providing the polygonal cylinder 50, the polygonal cylinder 50 is provided. It is conceivable that the shadow of the barrel 50 is projected onto the irradiation surface of the wafer W, and the uniformity of light irradiation distribution on the irradiation surface of the wafer W cannot be sufficiently achieved due to the shadow. In this regard, the height (separation distance from the wafer W) of the polygonal cylinder 50 is adjusted by the separation distance adjustment unit 60, so that, for example, the irradiation light from the adjacent polygonal cylinder 50 to the wafer W Diffusion can be adjusted, so areas that become shadows due to overlapping irradiated light can be eliminated. In addition, the height of the polygonal cylinder 50 adjusted by the separation distance adjusting unit 60 is determined, for example, by previously evaluating the irradiation angle from the deuterium lamp 40 and the illuminance of each part of the wafer W, etc. do.

Additionally, the light irradiation device may further include a wafer rotation unit 70 (substrate rotation unit) shown in FIG. 9 . The wafer rotation unit 70 is a mechanism that rotates the wafer W with the irradiation surface of the wafer W facing the deuterium lamp 40. Specifically, the wafer rotating unit 70 is connected to the loading table 20 on which the wafer W is loaded through a rotating shaft, and rotates the rotating shaft under the control of a controller (not shown) to connect the loading table 20 and The wafer W loaded on the loading table 20 is rotated. As the wafer W rotates, the irradiation location of the deuterium lamp 40 changes, so the uniformity of light irradiation distribution on the irradiation surface of the wafer W can be further improved. Additionally, the light irradiation device may rotate the polygonal cylinder 50 and the deuterium lamp 40 with respect to the wafer W, rather than the wafer W. Additionally, the light irradiation device may further include a parallel movement unit that reciprocates the polygonal cylinder 50 or the wafer W by about 10 mm in a direction parallel to the irradiation surface of the wafer W (horizontal direction). In this case as well, since the irradiation location of the deuterium lamp 40 changes, the uniformity of light irradiation distribution on the irradiation surface of the wafer W can be further improved. In addition, in the mode of reciprocating in a direction parallel to the irradiation surface, unlike the mode in which the wafer W is rotated, there is an advantage that a part (for example, the center of rotation) where the irradiation location does not change is unlikely to occur. For example, by rotating the plurality of polygonal cylinders 50 and the deuterium lamps 40 with respect to the wafer W and performing a scanning operation in a parallel direction, the number of deuterium lamps capable of simultaneously irradiating the entire surface of the wafer W is increased. Vacuum ultraviolet light can be irradiated to the entire surface of the wafer W without providing the lamp 40. In this way, when the polygonal cylinder 50 and the deuterium lamp 40 perform a scanning operation, etc., the polygonal cylinder 50 and the deuterium lamp 40 may be small in number (for example, one at a time).

Additionally, the light irradiation device may further include a diffusion portion 80 shown in FIG. 10. The diffusion section 80 is a member that diffuses vacuum ultraviolet light above the polygonal cylinder 50. In the example shown in FIG. 10, the diffusion portion 80 is a mesh-shaped member and has a function of reflecting and diffusing a part of the vacuum ultraviolet light. Additionally, the diffusion portion 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 section 80, the area of the portion that reflects and diffuses the vacuum ultraviolet light is smaller than the area of the portion that passes the vacuum ultraviolet light downward. The irradiated light originates from the internal electrode structure of the light source (lamp) and has intensity fluctuations. By providing the diffusion portion 80 above the polygonal tube 50, the fluctuations in the irradiated light are averaged, and the wafer (W ) can further improve the uniformity of light irradiation distribution on the irradiation surface.

In addition, the polygonal cylinder 50 has been described as having a regular hexagonal shape when viewed from the direction of travel of vacuum ultraviolet light, but it is not limited to this. For example, as shown in (a) of FIG. 11, the polygonal cylinder 50x has a square shape. It can be a shape. In addition, the number of polygonal cylinders 50 is not limited to the example shown in FIG. 3, and a total of 13 polygonal cylinders 50y may be provided, for example, as shown in FIG. 11(b).

In addition, although the light blocking part has been described as being a polygonal tube 50, the light blocking part is not limited to this, and the light blocking part may not be a cylindrical member extending in the height direction as long as it is formed in a polygonal shape when viewed from the direction in which vacuum ultraviolet light travels. For example, as shown in FIG. 12, the light blocking portion may have a mask 200 (plate shaped light blocking member) formed in a plate shape. The mask 200, like the polygonal cylinder 50, is formed in a polygonal shape when viewed from the direction in which vacuum ultraviolet light travels. Specifically, as shown in (a) of FIG. 13, a hexagonal mask 200a or a square-shaped mask 200b can be used when viewed from the direction in which vacuum ultraviolet light travels. Unlike the polygonal cylinder 50, the mask 200 is in the form of a thin plate with a small thickness (thickness in the direction in which vacuum ultraviolet light travels). By providing such a mask 200, the irradiation range of each vacuum ultraviolet light on the wafer W becomes polygonal, and while preventing the irradiation ranges of vacuum ultraviolet light from overlapping, the area to which the light is not irradiated (or irradiated) It is possible to suppress the occurrence of areas where strength is weakened. That is, according to the mask 200, the uniformity of light irradiation distribution on the irradiation surface of the wafer W can be improved. Additionally, since the mask 200 is in the form of a thin plate as described above, compared to the case where the polygonal cylinder 50 is provided, it is possible to easily perform exhaustion using a vacuum pump within the processing chamber. In this respect, vacuum suction within the processing chamber can be performed more appropriately.

In addition, as shown in FIG. 14, the light blocking portion extends in the direction of travel of vacuum ultraviolet light and is formed in a cylindrical shape, and is located between the deuterium lamp 40 and the wafer W at a position near the wafer W (i.e. near the bottom). You may have a polygonal cylinder 250 provided at the position of and a mask 200 formed in a plate shape. The polygonal cylinder 250 is, for example, less than half the total length between the deuterium lamp 40 and the wafer W. In this way, the polygonal cylinder 250 is smaller than the polygonal cylinder 50 (see FIG. 2) provided approximately throughout the entire area between the deuterium lamp 40 and the wafer W, and is provided only in the area close to the wafer W. there is. The mask 200 is provided below the polygonal cylinder 250, and more specifically, is provided 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 irradiation range of light, but the mask 200 may be provided at a distance (e.g., 30 mm) that allows transportation of the wafer W by the arm. It is spaced apart from the wafer (W). When viewed from the direction in which vacuum ultraviolet light travels, the mask 200 has an area through which light passes smaller than the polygonal cylinder 250. As a result, the irradiation range of vacuum ultraviolet light can be appropriately limited by the mask 200.

Here, the basic configuration of the substrate processing apparatus in 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 environment, and is configured to accommodate the wafer W transported by a transport mechanism (not shown). The housing 214 represents a cylindrical body with a bottom that opens upward. The wall surface of the housing 214 is provided with through holes 214a and 214c.

The rotation holding portion 216 has a rotating portion 216a, a shaft 216b, and a holding portion 216c. The rotation unit 216a operates based on an operation signal from a controller (not shown) and rotates the shaft 216b. The rotating part 216a is a power source such as an electric motor, for example. The holding portion 216c is provided at the distal end of the shaft 216b. The holding portion 216c is capable of holding the wafer W in a substantially horizontal state. When the rotation unit 216a rotates while the wafer W is loaded on the holding unit 216c, the wafer W rotates around an axis (rotation axis) perpendicular to its surface.

The gate valve 218 is disposed on the outer surface of the side wall of the housing 214. The gate valve 218 operates based on instructions from a 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 within the housing 214 and place the inside of the housing 214 in a vacuum state (hypoxic 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 container provided in an atmospheric atmosphere. The housing 224 represents a cylindrical body with a bottom that opens downward. The housing 224 is arranged so that the open ends of the housing 224 face the open ends of the housing 214 toward each other.

The partition wall 226 is disposed between the housings 214 and 224 and is configured to partition the space within the housing 214 and the space within the housing 224. In other words, the partition wall 226 functions as a ceiling wall of the housing 214 and also functions as a bottom wall of the housing 224. That is, the housing 224 is arranged adjacent to the housing 214 in a direction perpendicular to the surface of the wafer W. The space V within the housing 224 after being partitioned by the partition wall 226 is a flat space whose height in the vertical direction is small compared to 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 to overlap the shutter member 228 in the vertical direction. Each of the plurality of through holes 226a is blocked by a window member through which vacuum ultraviolet light can pass through. The window member may be, for example, glass (eg, magnesium fluoride glass).

The shutter member 228 is disposed 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 a disk shape, for example. The shutter member 228 is provided with a plurality of through holes.

By using the polygonal cylinder 250 and the mask 200 in combination as described above, the overlap of the irradiation ranges of the vacuum ultraviolet light by the polygonal cylinder 250 is appropriately suppressed, and the polygonal cylinder 250 is provided below the polygonal cylinder 250. The irradiation range of vacuum ultraviolet light can be appropriately limited by the mask 200. In addition, by using the mask 200, the length of the polygonal cylinder 250 can be shortened, and exhaustion by the vacuum pump 222 can be properly performed to vacuum the processing chamber 210. In addition, since the mask 200 is provided to be in contact with the lower end of the polygonal tube 250, leakage of vacuum ultraviolet light between the polygonal tube 250 and the mask 200 is suppressed, and the irradiation range of the vacuum ultraviolet light is reduced. Overlapping can be appropriately suppressed. Additionally, the light blocking portion may be formed only by the small polygonal cylinder 250 provided below (that is, without providing the mask 200).

Additionally, as shown in FIG. 15, the mask 200 may be provided to be spaced apart from the lower end of the polygonal cylinder 250. As a result, evacuation by the vacuum pump 222 becomes easier, and vacuum suction by the vacuum pump 222 can be performed more appropriately. In the configuration of Figure 15, the size of the area through which light passes through the mask 200 and the polygonal cylinder 50 may be approximately the same when viewed from the direction in which the vacuum ultraviolet light travels. Additionally, from the viewpoint of easily performing vacuum suction, 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 barrel (light blocking part, barrel-shaped light blocking member)
60: Separation distance adjustment unit
70: Wafer rotation unit (substrate rotation unit)
80: diffusion part
200: Mask (light blocking part, plate-shaped light blocking member)
W: wafer

Claims (20)

a plurality of light irradiation units that irradiate vacuum ultraviolet light taking a conical optical path with the light source as the vertex toward the substrate on which the resist pattern is formed;
A light-shielding unit provided corresponding to each light irradiation unit is provided to shield an overlapping portion of the irradiation range of the vacuum ultraviolet light irradiated from the plurality of light irradiation units,
The light irradiation device wherein the light blocking portion is formed in a polygonal shape when viewed from the direction in which the vacuum ultraviolet light travels. According to paragraph 1,
A light irradiation device, wherein the light blocking portion has a cylindrical light blocking member extending in the direction in which the vacuum ultraviolet light travels and formed into a cylindrical shape. According to paragraph 2,
The light irradiation device wherein the cylindrical light blocking member extends in the traveling direction over approximately the entire area between the light irradiation unit and the substrate. According to paragraph 2,
The light irradiation device wherein the cylindrical light blocking member is provided between the light irradiation unit and the substrate at a position near the substrate. According to clause 4,
The light irradiation device wherein the cylindrical light blocking member is less than half the total length between the light irradiation unit and the substrate. According to any one of claims 1 to 5,
A light irradiation device wherein the light blocking portion has a plate-shaped light blocking member formed in a plate shape. According to paragraph 1,
The light-shielding portion has a cylindrical light-shielding member that extends in the direction in which the vacuum ultraviolet light travels and is formed in a cylindrical shape and is provided at a position near the substrate between the light irradiation portion and the substrate, and a plate-shaped light-shielding member that is formed in a plate shape,
The light irradiation device wherein the plate-shaped light-shielding member is provided below the cylindrical light-shielding member. In clause 7,
A light irradiation device, wherein the plate-shaped light-shielding member is provided to be in contact with a lower end of the cylindrical light-shielding member. According to clause 8,
A light irradiation device, wherein the plate-shaped light blocking member has a smaller area through which light passes when viewed from the traveling direction than the cylindrical light blocking member. In clause 7,
A light irradiation device, wherein the plate-shaped light blocking member is provided to be spaced apart from a lower end of the cylindrical light blocking member. According to any one of claims 1 to 5 and 7 to 10,
A light irradiation device further comprising a separation distance adjusting unit that adjusts a separation distance of the light blocking unit from the substrate. According to any one of claims 1 to 5 and 7 to 10,
A light irradiation device in which the light irradiation unit is configured to include a deuterium lamp. According to clause 12,
The deuterium lamp is a light irradiation device that generates vacuum ultraviolet light with a wavelength of 200 nm or less. According to clause 13,
The deuterium lamp is a light irradiation device that generates vacuum ultraviolet light with a wavelength of 160 nm or less. According to any one of claims 1 to 5 and 7 to 10,
The light irradiation device wherein the plurality of light irradiation units differ from each other in at least one of an illuminance value of the vacuum ultraviolet light to be irradiated, a beam angle of the vacuum ultraviolet light to be irradiated, and a separation distance from the substrate. According to any one of claims 1 to 5 and 7 to 10,
A light irradiation device further comprising a diffusion portion above the light shielding portion that diffuses the vacuum ultraviolet light. According to any one of claims 1 to 5 and 7 to 10,
A light irradiation device further comprising a substrate rotation unit that rotates the substrate with the irradiation surface of the substrate facing the light irradiation unit. According to any one of claims 1 to 5 and 7 to 10,
A light irradiation device further comprising a parallel moving part that reciprocates the light blocking part or the substrate in a direction parallel to the irradiation surface of the substrate. According to any one of claims 1 to 5 and 7 to 10,
A light irradiation device in which the light blocking portion is made of a material having a reflectance of vacuum ultraviolet light of 90% or less. A plurality of light irradiation units that irradiate vacuum ultraviolet light taking a conical optical path with the light source as the vertex toward the substrate,
A light-shielding unit provided corresponding to each light irradiation unit is provided to shield an overlapping portion of the irradiation range of the vacuum ultraviolet light irradiated from the plurality of light irradiation units,
The light blocking portion is formed in a polygonal shape when viewed from the direction in which the vacuum ultraviolet light travels,
The light-shielding portion has a cylindrical light-shielding member that extends in the direction in which the vacuum ultraviolet light travels and is formed in a cylindrical shape and is provided at a position near the substrate between the light irradiation portion and the substrate, and a plate-shaped light-shielding member that is formed in a plate shape,
The light irradiation device wherein the plate-shaped light-shielding member is provided below the cylindrical light-shielding member.

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