JP4124448B2 - Substrate processing method and substrate processing apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate processing method and a substrate processing apparatus for processing a glass substrate or a semiconductor substrate used for, for example, a liquid crystal display device.
[0002]
[Prior art]
In the manufacturing process of LCD (Liquid Crystal Display), in order to form a thin film or electrode pattern of ITO (Indium Tin Oxide) on a glass substrate for LCD, there is a photolithography technique similar to that used for manufacturing semiconductor devices. Used. In the photolithography technique, a photoresist is applied to a glass substrate, which is exposed and further developed.
[0003]
There is a so-called half exposure as a method for performing the exposure. In the case of normal exposure, the non-exposed part is covered with a mask and shielded from light. On the other hand, in half exposure, a halftone mask or the like having a difference in light transmittance is used in one mask to be used, for example, a portion where the exposure amount is smaller than in a normal case, that is, the depth of the resist to be exposed. It is possible to intentionally form a portion that is partially shallow. As a result, the difference in exposure depth, such as a portion not covered with a mask (a portion that is completely exposed), a portion covered with a halftone (a portion where exposure is shallow), and a portion covered with a mask (a portion that is not exposed). It is possible to form different resist film thicknesses with a single mask. Therefore, in the half exposure, the number of masks to be used can be reduced, and the processing time can be shortened by the amount corresponding to the mask exchange process (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
Japanese Unexamined Patent Publication No. 09-080740 (paragraphs [0002], [0003], etc.).
[0005]
[Problems to be solved by the invention]
Usually, a halftone mask is provided with a plurality of semi-light-shielding portions having the same shape and the same area, and it is desirable that the half-exposure has the same depth and width.
[0006]
However, in the case of half exposure, the depth and width of half exposure differ depending on the portion irradiated with light, and the remaining resist film after development becomes non-uniform. That is, there is a problem that the aspect ratio and pitch of the resist pattern after development become non-uniform. In fact, there is a variation of 10% or more with respect to the desired value. For this reason, for example, the distance between a plurality of electrodes formed after etching becomes non-uniform, and the switching time varies depending on the location, which causes color unevenness when displaying an image by liquid crystal, for example.
[0007]
In view of the above circumstances, an object of the present invention is to provide a substrate processing method and a substrate processing apparatus capable of improving the uniformity of a residual film in a half-exposed portion.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a substrate processing method according to the present invention includes: (a) a step of applying a resist on the surface of a substrate; and (b) baking the resist on the surface of the resist applied on the surface of the substrate. A solidified first layer is formed, a heated second layer is formed on the back side of the resist, and a third layer containing moisture is contained between the first layer and the second layer. Heating the resist from the front side and the back side of the substrate so that a layer is formed , and (c) half-exposing the heated resist.
[0009]
With such a configuration, the resist can be dried from the back side of the substrate, and the surface of the resist can be baked. The resist surface is baked and hardened to suppress evaporation of moisture due to heating from the back surface, and a certain amount of moisture remains inside the resist. As a result, a flat layer with a low water content is formed on the back side of the resist, and a layer containing residual water is formed from the resist surface to the middle. Moisture is required for the resist to undergo an exposure reaction. In the half exposure, the exposure reaction does not occur in an area where the resist has a small amount of water, so that the flat layer on the back side of the resist is not exposed. By development, a flat layer in which this exposure reaction does not occur becomes a residual film. In this way, a flat layer in which the residual film after development is not affected by the exposure dose can be formed at a certain depth of the resist, and the dissolution characteristics in the depth direction of the resist can be controlled. Thereby, the uniformity of the remaining film of the half-exposed part can be improved. Here, half-exposure means, for example, a halftone mask having a difference in light transmittance, etc., and a portion where the exposure amount is smaller than in normal exposure, that is, the depth of the resist to be exposed is partially An exposure method for intentionally forming a shallow portion (hereinafter the same).
[0010]
In the substrate processing method according to an aspect of the present invention, the step (b) includes: (d) a step of heating at a first temperature from the front side of the substrate; and (e) a second from the back side of the substrate. And a step of heating at the temperature.
[0011]
With such a configuration, since the first temperature and the second temperature can be set separately, even when the resist type is different, heating can be performed at an optimum temperature independently in each step.
[0012]
In the substrate processing method according to one aspect of the present invention, the step (d) includes a step of heating at 70 ° C. to 200 ° C. from the surface side of the substrate.
[0013]
If it is such a structure, it can heat at the optimal temperature according to the kind of resist by changing 1st temperature with 70 to 200 degreeC.
[0014]
In the substrate processing method according to one aspect of the present invention, the step (e) includes a step of heating at 90 ° C. to 150 ° C. from the back side of the substrate.
[0015]
If it is such a structure, it can heat at the optimal temperature according to the kind of resist by changing 2nd temperature with 90 to 150 degreeC.
[0016]
The substrate processing method according to an aspect of the present invention further includes (f) a step of adjusting an atmospheric pressure applied to at least the resist during the step (b).
[0017]
With such a configuration, even when the type of resist is different, in each step, heating can be performed at an optimal pressure corresponding to the type of resist.
[0018]
In the substrate processing method according to an aspect of the present invention, the step (f) includes a step of reducing the pressure applied to at least the resist by 5 Pa to 100 Pa from normal pressure during the step (b).
[0019]
With such a configuration, the pressure applied to the resist can be variably reduced from normal pressure to 5 Pa to 100 Pa so that the resist can be heated at an optimum pressure corresponding to the type of resist even when the type of resist is different. it can.
[0020]
In the substrate processing method according to an aspect of the present invention, the step (b) includes a step of adjusting a heating time for heating the resist to 60 seconds to 300 seconds.
[0021]
With such a configuration, by changing the resist heating time from 60 seconds to 300 seconds, even when the resist type is different, the resist can be heated with the optimum heating time according to the resist type.
[0022]
A substrate processing apparatus according to the present invention is a substrate processing apparatus capable of transferring the substrate to and from an exposure apparatus that half-exposes a resist applied on the substrate, wherein the resist is applied to the surface of the substrate. A first layer in which the resist is baked and hardened is formed on the surface of the resist applied to the surface of the substrate , and a heated second layer is formed on the back side of the resist. A heating unit for heating the resist from the front side and the back side of the substrate so that a third layer containing moisture is formed between the first layer and the second layer ; An interface unit capable of passing the substrate heated by the heating unit to the exposure apparatus.
[0023]
If it is such a structure, the resist apply | coated by the application part by the heating from the back surface side of a board | substrate among heating parts can be dried, and the surface of this resist can be baked and hardened by the heating from the surface side of a board | substrate. . The resist surface is baked and hardened to suppress evaporation of moisture due to heating from the back surface, and a certain amount of moisture remains inside the resist. As a result, a flat layer with a low water content is formed on the back side of the resist, and a layer containing residual water is formed from the resist surface to the middle. Moisture is required for the resist to undergo an exposure reaction. In the half exposure, the exposure reaction does not occur in an area where the resist has a small amount of water, so that the flat layer on the back side of the resist is not exposed. By development, a flat layer in which this exposure reaction does not occur becomes a residual film. In this way, a flat layer in which the residual film after development is not affected by the exposure dose can be formed at a certain depth of the resist by the heating unit, and as a result, the dissolution characteristics in the depth direction of the resist during development are controlled. can do. Thereby, the uniformity of the remaining film of the half-exposed part can be improved.
[0024]
In the substrate processing apparatus according to one aspect of the present invention, the heating unit heats the resist applied to the surface of the substrate at a first temperature from the surface side of the substrate; A second hot plate that heats the resist applied to the surface of the substrate from the back side of the substrate at a second temperature.
[0025]
With such a configuration, since the temperature plate that is heated at the first temperature and the heat plate that is heated at the second temperature can be independently set, each of the resist types is different even when the resist type is different. The heating plate can be heated at an optimum temperature according to the type of resist.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0027]
(Coating and developing equipment)
1 is a plan view showing an LCD substrate coating and developing apparatus to which the present invention is applied, FIG. 2 is a front view thereof, and FIG. 3 is a rear view thereof.
[0028]
The coating and developing treatment apparatus 1 includes a cassette station 2 on which a cassette C that accommodates a plurality of glass substrates G is placed, and a plurality of processing units for performing a series of processes including resist coating and development on the substrate G. An interface unit 4 for transferring the substrate G between the processing unit 3 and the exposure apparatus 32 is provided, and a cassette station 2 and an interface unit 4 are disposed at both ends of the processing unit 3, respectively.
[0029]
The cassette station 2 includes a transport mechanism 10 for transporting the LCD substrate between the cassette C and the processing unit 3. Then, loading and unloading of the cassette C is performed at the cassette station 2. In addition, the transport mechanism 10 includes a transport arm 11 that can move on a transport path 12 provided along the cassette arrangement direction, and the transport arm 11 can transport the substrate G between the cassette C and the processing unit 3. Done.
[0030]
The processing unit 3 includes an upstream part 3b in which processing units including a resist coating processing unit (CT) are arranged in parallel along the X direction and a downstream part in which processing units including a development processing unit (DEV) are arranged in parallel. 3c.
[0031]
In the upstream part 3b, an excimer UV processing unit (e-UV) 19 for removing organic substances on the substrate G from the cassette station 2 side and a cleaning process on the substrate G with a scrubbing brush are provided at the end of the cassette station 2 side. And a scrubber cleaning processing unit (SCR).
[0032]
Next to the scrubber cleaning unit (SCR), thermal processing blocks 24 and 25 in which units for performing thermal processing on the glass substrate G are stacked in multiple stages are arranged. Between these heat treatment blocks 24 and 25, the vertical transfer unit 5 is arranged, and the transfer arm 5a is movable in the Z direction and the horizontal direction and is rotatable in the θ direction. The substrate G is transferred by accessing each heat treatment system unit in the blocks 24 and 25. The vertical transport unit 7 has the same configuration as the vertical transport unit 5.
[0033]
As shown in FIG. 2, the heat treatment system block 24 includes a baking unit (BAKE) for performing a heat treatment before applying a resist to the substrate G, and an adhesion unit (AD) for performing a hydrophobizing treatment with HMDS gas. They are stacked in order from the bottom. On the other hand, in the heat treatment system block 25, two stages of cooling units (COL) for performing a cooling process on the substrate G, an adhesion unit (AD), and a transfer device 30 are stacked in order from the bottom.
[0034]
A resist processing block 15 extends in the X direction adjacent to the heat treatment block 25. The resist processing block 15 includes a resist coating processing unit (CT) for applying a resist to the substrate G, a reduced pressure drying unit (VD) for drying the applied resist under reduced pressure, and a peripheral portion of the substrate G according to the present invention. And an edge remover (ER) for removing the resist. The resist processing block 15 is provided with a sub arm (not shown) that moves from the resist coating processing unit (CT) to the edge remover (ER) so that the substrate G is transported in the resist processing block 15 by the sub arm. It has become.
[0035]
A multi-stage heat treatment system block 26 is disposed adjacent to the resist processing block 15. The heat treatment system block 3 includes three pre-baking units (PREBAKE) for performing a heat treatment after the resist is applied to the substrate G. It is laminated and the conveying device 40 is provided thereunder.
[0036]
In the downstream portion 3c, as shown in FIG. 3, a heat treatment system block 29 is provided at the end on the interface portion 4 side, which includes a cooling unit (COL), a heat treatment before the development process after the exposure. Post-exposure baking units (PEBAKE) that perform the above are stacked in order from the bottom.
[0037]
A development processing unit (DEV) that performs development processing adjacent to the heat treatment system block 29 extends in the X direction. Next to the development processing unit (DEV), heat treatment system blocks 28 and 27 are arranged. Between these heat treatment system blocks 28 and 27, the same structure as the vertical transport unit 5 is provided. And 27, a vertical transfer unit 6 accessible to each heat treatment system unit is provided. Further, an i-line processing unit (i-UV) 33 is provided adjacent to the development processing unit (DEV).
[0038]
In the heat treatment block 28, a cooling unit (COL) and a post baking unit (POBAKE) for performing heat treatment after development on the substrate G are stacked in order from the bottom. On the other hand, in the heat treatment block 27, similarly, a cooling unit (COL) and a post baking unit (POBAKE) are stacked in order from the bottom.
[0039]
The interface unit 4 is provided with a titler and peripheral exposure unit (Title / EE) 22 on the front side, an extension cooling unit (EXTCOL) 35 adjacent to the vertical transfer unit 7, and a buffer cassette 34 on the back side. The vertical transfer unit 8 is arranged to transfer the substrate G between the titler / peripheral exposure unit (Title / EE) 22, the extension cooling unit (EXTCOL) 35, the buffer cassette 34, and the exposure apparatus 32 adjacent thereto. Has been placed. The vertical transport unit 8 has the same configuration as the vertical transport unit 5.
[0040]
(Coating development process)
The processing steps of the coating and developing processing apparatus 1 configured as described above will be described. First, the substrate G in the cassette C is transported to the upstream part 3b in the processing part 3 part. In the upstream portion 3b, surface modification / organic matter removal processing is performed in the excimer UV processing unit (e-UV) 19, and then in the scrubber cleaning processing unit (SCR), the cleaning process and the substrate G are transported substantially horizontally. A drying process is performed. Subsequently, the substrate G is taken out by the transfer arm 5a in the vertical transfer unit at the lowermost stage of the heat treatment system block 24, heated in the baking unit (BAKE) of the heat treatment system block 24, and in the adhesion unit (AD). In order to improve the adhesion between the glass substrate G and the resist film, a process of spraying HMDS gas onto the substrate G is performed. Thereafter, a cooling process by a cooling unit (COL) of the heat treatment system block 25 is performed.
[0041]
Next, the substrate G is transferred from the transfer arm 5a to the transfer device 30, and the transfer device 30 transfers the substrate G to the resist coating processing unit (CT). After the resist coating processing is performed, the reduced-pressure drying processing unit ( VD) is subjected to a vacuum drying process, and an edge remover (ER) is sequentially subjected to resist removal processing on the periphery of the substrate.
[0042]
Next, the substrate G is transferred to the transfer device 40, and is transferred to the transfer arm of the vertical transfer unit 7 by the transfer device 40. Then, after the heat treatment is performed in the pre-baking unit (PREBAKE) in the heat treatment block 26, the cooling treatment is performed in the cooling unit (COL) in the heat treatment block 29. Subsequently, the substrate G is cooled by an extension cooling unit (EXTCOL) 35 and exposed by an exposure apparatus.
[0043]
Next, the substrate G is transferred to the post-exposure baking unit (PEBAKE) of the heat treatment system block 29 via the transfer arms of the vertical transfer units 8 and 7, and after the heat treatment is performed here, the substrate G is transferred to the cooling unit (COL). The cooling process is performed. Then, the developing process, the rinsing process and the drying process are performed while the substrate G is transported substantially horizontally in the development processing unit (DEV) via the transport arm of the vertical transport unit 7.
[0044]
Next, the substrate G is transferred from the lowermost stage in the heat treatment system block 28 by the transfer arm 6a of the vertical transfer unit 6, and is subjected to a heat treatment in the post baking unit (POBAKE) in the heat treatment system block 28 or 27, and the cooling unit. The cooling process is performed at (COL). The substrate G is transferred to the transport mechanism 10 and accommodated in the cassette C.
[0045]
(Heat treatment equipment)
Next, based on FIG. 4, the prebaking unit provided in the heat processing block of the substrate processing apparatus according to the present invention will be described. FIG. 4 is a sectional view of the pre-baking unit and shows the internal structure.
[0046]
The pre-baking unit 38 that heats the resist R applied to the substrate G has a processing chamber 42 and an upper drive mechanism 43 therein. The processing chamber 42 is where the substrate G is actually heated. The upper plate 45 that heats the resist R from the front side of the substrate G, the lower plate 46 that heats the resist R from the back side of the substrate G, and the processing chamber 42. It has an exhaust port 47 for exhausting the gas inside.
[0047]
The upper plate 45 is provided so as to be vertically movable in the processing chamber 42 by the upper air cylinder 51 constituting the upper drive mechanism 43. The upper piston 52 of the upper air cylinder 51 is attached to the support member 54 through a through hole 42 c opened in the ceiling 42 a of the processing chamber 42. The upper plate 45 can be moved up and down by the vertical movement of the piston 52.
[0048]
The lower plate 46 is placed on the floor 42 b of the processing chamber 42. The lower plate 46 includes a proximity pin 55 that creates a gap between the lower plate 46 and a through hole 56 through which a support pin 57 that supports the substrate G when the substrate G is placed on the proximity 55. The support pin 57 can be moved up and down in the vertical direction by an air cylinder, a stepping motor or the like (not shown).
[0049]
The upper plate 45 and the lower plate 46 are made of a metal such as aluminum, for example, and a heating mechanism such as a heating wire (not shown) is provided inside. Each of the plates 45 and 46 is provided with a heating control unit 70. The heating temperature and heating time of the plates 45 and 46 are controlled by the heating controller 70. The exhaust port 47 is connected to the pump 50 via a pipe 48. The pump 50 is provided with an atmospheric pressure control unit 73 that controls the exhaust pressure during heating. Control of the atmospheric pressure in the processing chamber 42 is performed by controlling the pump 50 by the atmospheric pressure control unit 73.
[0050]
Next, a control system for controlling the heating temperature and heating time of each plate will be described with reference to FIG.
[0051]
As shown in FIG. 5A, the heating control unit 70 includes a heating temperature control unit 71 and a heating time control unit 72. The heating temperature control unit 71 is divided into an upper plate temperature control unit 71 a that controls the temperature of the upper plate 45 and a lower plate temperature control unit 71 b that controls the temperature of the lower plate 46, and the temperature of the upper plate 45 and the lower plate 46. Are controlled independently. Thereby, it can heat at the optimal temperature according to the kind of resist. The upper plate temperature control unit 71a and the lower plate temperature control unit 71b are connected to, for example, heating wires of the plates 45 and 46, respectively, and control the magnitude of the current flowing through each heating wire to control the respective plates 45 and 46. Control the temperature. The heating time control unit 72 that controls the heating time of the upper plate 45 and the lower plate 46 is attached to a heating mechanism such as a heating wire of each of the plates 45 and 46. When the predetermined time has passed, for example, the heating time of the plates 45 and 46 is controlled by stopping the current flowing through the heating wire. As shown in FIG. 5B, the heating time control unit 72 has an upper plate time control unit 72a and a lower plate time control unit 72b, and controls the heating time by the plates 45 and 46 independently. Anyway. Thereby, it can heat at the optimal temperature according to the kind of resist.
[0052]
(Substrate processing process)
Next, the substrate processing process will be described.
[0053]
FIG. 6 is a flowchart showing the steps of the present invention. In the resist processing block 15, a resist R is applied to the surface of the substrate G by, eg, spin coating (step 1). The material of the resist R is, for example, a novolac resin type.
[0054]
Next, the resist R is heated by the upper plate 45 and the lower plate 46 in the pre-baking unit 38 of the heat treatment block 26 (step 2). When the substrate is carried into the pre-baking unit 38, the upper plate may be appropriately moved up and down by the upper drive mechanism 43 so that the substrate G can be easily carried in. The substrate G is placed on the support pins 57 and placed on the proximity pins 55 by the lower drive mechanism as shown in FIG. In this state, the resist R is heated by the upper plate 45 and the lower plate 46. In order to facilitate understanding of the figure, the ratio of the thickness of the resist R to the thickness of the substrate is schematically shown in an enlarged manner. At the stage of starting the heating, the resist R contains a sufficient amount of moisture, and the resist R in a state of sufficiently containing the moisture is indicated by reference numeral 62. When heating, the upper plate 45 may be appropriately moved up and down by the upper drive mechanism 43.
[0055]
FIG. 8 shows the heating conditions in step 2 in a table. The upper column of the table shows the optimum control range for the heating control unit 70 and the atmospheric pressure control unit 73, and the lower column shows the optimum value when the novolac resin system in this embodiment is a resist material. Regarding the optimum control range, it is preferable that the temperature of the plate is heated in the range of 70 to 200 ° C. for the upper plate 45 and 90 to 150 ° C. for the lower plate 46. This is because the optimum heating temperature differs depending on the type of resist. For this reason, the upper plate temperature control unit 71a and the lower plate temperature control unit 71b of the heating temperature control unit 71 are set in advance so that the temperature can be controlled within the above range. By setting the temperature range in this manner, heating can be performed with an optimum value corresponding to the type of resist.
[0056]
The heating time of the plate is preferably set in the heating time control unit 72 and controlled in the range of 60 seconds to 300 seconds depending on the type of resist. The exhaust pressure from the exhaust port 47 is preferably controlled by setting the atmospheric pressure control unit 73 so that the pressure is reduced from normal pressure to 5 Pa to 100 Pa depending on the type of resist.
[0057]
In the novolac resin-based resist R of this embodiment, the temperature of the upper plate 45 is 70 ° C. to 200 ° C., the temperature of the lower plate 46 is about 135 ° C., the heating time is about 180 seconds, and the exhaust pressure is reduced from normal pressure to 10 Pa to 50 Pa. It is the optimum value to be a value that is determined. Therefore, the heating temperature control unit 71, the heating time control unit 72, and the atmospheric pressure control unit 73 are controlled so as to be heated in this range.
[0058]
When the resist R is heated under these conditions, as shown in FIG. 7B, a heated portion 63 in which the surface of the resist R is baked and hardened by the heating by the upper plate 45 is formed. Further, the moisture is evaporated by the heating by the lower plate 46, and the drying section 64 with relatively little moisture is formed. By forming the fired portion 63, moisture that is originally evaporated by heating from the lower plate 64 is suppressed, and a moisture-containing portion 62 having relatively much moisture remains between the fired portion 63 and the drying portion 64.
[0059]
Next, in this state, the heating of the resist R is finished and exposure is performed (step 3). The state at this time is shown in FIG.
[0060]
FIG. 9A shows how exposure is performed for the exposure areas A, B, and C of the resist R. FIG. Hereinafter, in the present embodiment, when there is a difference in the amount of exposure light irradiated to the resist R between the exposure region B and the exposure region C, for example, the exposure region C has a larger irradiation amount than the exposure region B. explain.
[0061]
Exposure is performed by the exposure device 32. The resist R is covered with a mask 65, and the resist R is irradiated with ultraviolet rays from above the mask 65. In the exposure area A, normal exposure is performed. For this reason, a hole is made in a portion corresponding to the exposure area A of the mask 65 so that the irradiation light is totally transmitted. Further, half exposure is performed in the exposure regions B and C. For this reason, the halftone 65a is used in the portions corresponding to the exposure regions B and C so that the irradiated light is almost semi-transmitted.
[0062]
FIG. 9B shows a state in the middle of exposing the resist R, and shows a state in which the exposure reaction in the region C has been performed up to the drying unit 64. In the area A, the exposure reaction is performed up to the point where the surface of the drying unit 64 is slightly advanced. In the region B, the exposure reaction is performed up to about half of the moisture-containing portion 62. Since the exposure reaction occurs according to the magnitude of the exposure amount, there is a difference in the way the reaction proceeds in each region during the exposure.
[0063]
FIG. 9C shows a state when the resist R is further irradiated with ultraviolet rays (g-line, i-line) from this state and the exposure is completed. In the region A, an exposure reaction occurs in all of the baking portion 63, the moisture-containing portion 62, and the drying portion 64 of the resist R. In the regions B and C, the intensity of the exposure light applied to the resist R is smaller than that in the exposure region A, and an exposure reaction occurs in the baking portion 63 and the moisture-containing portion 62, but an exposure reaction occurs up to the drying portion 64. Absent. Compared with FIG. 9B, no exposure reaction has occurred in the region C from the point where it has reached the moisture-containing portion 63. As described above, in regions B and C, the exposure depth of the resist R does not change even if the irradiation amount is different.
[0064]
Next, the resist R is developed (step 4). The state at this time is shown in FIG. FIG. 10A shows how the developer is supplied to the exposed resist R. FIG. Development is performed in a developing unit processing unit (DEV) provided in the downstream portion 3 of the coating and developing processing apparatus 1. The developer 67 discharged from the nozzle 66 is supplied to the surface of the resist R. As shown in FIG. 10B, the developer 67 dissolves the portion of the resist R where the exposure reaction has occurred. In this process, the resist R remains undissolved in the portion covered with the mask at the time of exposure, and all the resist R in the region A is dissolved. In addition, in the regions B and C covered with the halftone 65a, only the drying portion 64 where the exposure reaction has not occurred remains without being dissolved. According to this embodiment, the film thickness of the remaining film in the exposure regions B and C is the thickness of the drying unit 64, and is approximately 8000 mm. As described above, the remaining film can be made constant even though the exposure amounts in the regions B and C are different.
[0065]
FIG. 11 to FIG. 13 show the results of experiments on this embodiment. Each graph is a graph showing the relationship between the exposure amount and the residual resist film thickness, with the horizontal axis representing the exposure amount and the vertical axis representing the residual resist film thickness. The type of resist used was a novolak resin type as in this embodiment.
[0066]
FIG. 11 shows the relationship between the exposure amount and the residual resist film thickness when the temperature of the lower plate 46 is set to 135 ° C. and the temperature of the upper plate 45 is changed to 70 ° C., 135 ° C., and 200 ° C., respectively. Show. In addition, the relationship when the upper plate 45 is not used during heating is also shown.
[0067]
When the temperature of the upper plate 45 is 70 ° C., 135 ° C., and 200 ° C., the residual resist film thickness is a constant value of approximately 3000 mm in the range of the exposure dose of 10 to 20 (mJ / cm ² ). It can be seen that the temperature of the upper plate 45 has little influence on the residual resist film thickness. From this result, if the exposure amount of the half exposure is controlled to be in the range of 10 to 20 (mJ / cm ² ), preferably 15 to 20 (mJ / cm ² ), the resist residual film is also caused by the fluctuation of the exposure amount. The thickness can be made uniform.
[0068]
In FIG. 12, when the temperature of the lower plate 46 is set to 135 ° C., the temperature of the upper plate 46 is arbitrarily set in the range of 70 ° C. to 200 ° C., and heating is performed for 180 seconds, the exhaust pressure is 10 Pa, 50 Pa, 100 Pa. And the relationship between the exposure amount and the residual resist film thickness when changed.
[0069]
When the value of the exhaust pressure is 10 Pa, the residual resist film thickness is about 8000 mm in an exposure amount range of 10 to 20 (mJ / cm ² ), which is an almost constant value. When the value of the exhaust pressure is 50 Pa, the residual resist film thickness slightly changes from 6000 to 7000 mm within the range of the exposure amount from 10 to 20 (mJ / cm ² ). On the other hand, when the value of the exhaust pressure is 100 Pa, the residual resist film thickness decreases with an increase in the exposure amount even if the exposure amount is in the range of 10 to 20 (mJ / cm ² ), and greatly changes from 1000 to 6000 mm. . From this result, if the exhaust amount at the time of heating is controlled to 10 to 50 Pa, preferably about 10 Pa, the resist residual film thickness can be made uniform in the range of the exposure amount of 10 to 20 (mJ / cm ² ). If the exhaust amount is set to the above value, a substantially ideal resist residual film thickness of about 8000 mm can be obtained.
[0070]
FIG. 13 shows that when the lower plate 46 is heated to 115 ° C. and the upper plate is not used, when the upper plate is used and the temperature is 200 ° C., the temperature is set to 200 using the upper plate. It shows the value when the temperature is set to 0 ° C. and the substrate is turned over (the surface coated with the resist R faces the lower plate 46) and heated.
[0071]
In either case, the residual resist film thickness does not take a constant value, and the residual resist film thickness decreases as the exposure amount increases. However, for example, the resist residual film thickness may be set to a constant value by setting the exhaust pressure and the heating time to appropriate values.
[0072]
【The invention's effect】
As described above, according to the present invention, the uniformity of the remaining film in the half-exposed part can be improved.
[Brief description of the drawings]
FIG. 1 is a plan view showing an overall configuration of a coating and developing treatment apparatus according to an embodiment of the present invention.
FIG. 2 is a front view of the coating and developing treatment apparatus shown in FIG.
FIG. 3 is a rear view of the coating and developing treatment apparatus shown in FIG.
FIG. 4 is a cross-sectional view of a pre-baking unit.
FIG. 5 is a diagram showing a heat treatment control system;
FIG. 6 is a process chart showing a substrate processing method according to the present invention.
FIG. 7 is a diagram illustrating a state in which heat treatment is performed on a resist.
FIG. 8 is a diagram showing optimum conditions during heat treatment.
FIG. 9 is a diagram showing a state of change when exposure light is irradiated to a resist.
FIG. 10 is a diagram illustrating a state when a developing solution is supplied to a resist.
FIG. 11 is a graph showing a relationship between an exposure amount and a residual film thickness of a resist after development.
FIG. 12 is a graph showing a relationship between an exposure amount and a residual film thickness of a resist after development.
FIG. 13 is a graph showing a relationship between an exposure amount and a residual film thickness of a resist after development.
[Explanation of symbols]
G ... Substrate R ... Resist 1 ... Application and development processing device 45 ... Upper plate 46 ... Lower plate 47 ... Exhaust port 62 ... Moisture containing part 63 ... Burning part 64 ... Drying part 65a ... Halftone part 71a ... Upper plate temperature control part 71b ... Lower plate temperature control unit 72 ... Heating time control unit 73 ... Pressure control unit

Claims (9)

(A) applying a resist to the surface of the substrate;
(B) a first layer formed by baking the resist on the surface of the resist applied to the surface of the substrate is formed, and a heated second layer is formed on the back side of the resist; Heating the resist from the front surface side and the back surface side of the substrate so that a third layer containing moisture is formed between the first layer and the second layer ;
(C) half-exposure of the heated resist, and a substrate processing method. The substrate processing method according to claim 1,
The step (b)
(D) heating from the surface side of the substrate at a first temperature;
(E) A step of heating at a second temperature from the back side of the substrate. The substrate processing method according to claim 2,
The step (d)
The substrate processing method characterized by including the process of heating at 70 to 200 degreeC from the surface side of the said board | substrate. The substrate processing method according to claim 2,
The step (e)
The substrate processing method characterized by including the process of heating at 90 to 150 degreeC from the back surface side of the said board | substrate. The substrate processing method according to claim 1,
(F) The substrate processing method further comprising the step of adjusting the pressure applied to at least the resist during the step (b). The substrate processing method according to claim 5,
The step (f)
A substrate processing method comprising: a step of reducing the pressure applied to the resist by at least 5 Pa to 100 Pa from normal pressure. The substrate processing method according to claim 1,
The step (b)
Adjusting the heating time for heating the resist to 60 seconds to 300 seconds. A substrate processing apparatus capable of transferring the substrate to and from an exposure apparatus that half-exposes a resist applied on a substrate,
An application part for applying a resist to the surface of the substrate;
A first layer in which the resist is baked and hardened is formed on the surface of the resist applied to the surface of the substrate , and a heated second layer is formed on the back side of the resist, and the first layer And a heating unit for heating the resist from the front surface side and the back surface side of the substrate, so that a third layer containing moisture is formed between the first layer and the second layer ,
And an interface unit capable of passing the substrate heated by the heating unit to the exposure apparatus. The substrate processing apparatus according to claim 8, comprising:
The heating unit is
A first hot plate that heats the resist applied to the surface of the substrate from the surface side of the substrate at a first temperature;
A substrate processing apparatus comprising: a second heating plate that heats the resist applied to the surface of the substrate at a second temperature from the back side of the substrate.

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