JP2008198970A - Coating method, program, and computer storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To planarize the surface of a coating, when forming the coating on a predetermined pattern formed on a substrate. <P>SOLUTION: A wafer having a pattern formed thereon is rotated (step S1) and a coating solution containing a liquid coating forming component is applied to the center of the wafer (step S2). When the coating solution is diffused over the pattern of the wafer by a centrifugal force generated by the rotation of the wafer, ultraviolet rays are emitted to the applied coating solution (step S3). The emitted ultraviolet rays activate a photopolymerization initiator contained in the coating solution and cure the coating solution (step S4). Thus, the coating is formed on the pattern of the wafer (step S5). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a coating processing method, a program, and a computer storage medium for forming a coating film on a pattern formed on a substrate.

  For example, in a manufacturing process of a semiconductor device having a multilayer wiring structure, for example, a resist coating process for applying a resist solution on a semiconductor wafer (hereinafter referred to as “wafer”) to form a resist film, and exposing a predetermined pattern on the resist film An exposure process for developing and a development process for developing the exposed resist film are sequentially performed to form a predetermined resist pattern on the wafer. Using this resist pattern as a mask, the wafer is etched, and then the resist film is removed to form a predetermined pattern on the wafer. Thus, the process of forming a predetermined pattern in a predetermined layer is usually repeated about 20 to 30 times, and a semiconductor device having a multilayer wiring structure is manufactured.

  By the way, when a predetermined pattern is repeatedly formed on the wafer in this way, the (n + 1) -th layer resist film is formed at an appropriate height after the predetermined pattern is formed on the n-th layer. The surface to which the resist solution is applied needs to be flat.

Therefore, conventionally, a coating film is formed on a predetermined pattern of a wafer and the surface thereof is flattened. Such a coating film is formed by, for example, applying a coating liquid having a solid coating film forming component and a solvent on a predetermined pattern of a wafer, and heating and curing the applied coating liquid. . As this coating liquid, for example, SOG (SpinOn
Glass) material is used. (Non-Patent Document 1)

Naohashi Ohashi et al. "Improvement of SOG process for multilayer wiring structure" IEICE Transactions C-II Vol. J78-C-II No. 5 1995

  However, as shown in FIG. 16, when such a conventional coating solution is applied onto the predetermined pattern P of the wafer W, the fluidity of the solid coating film forming component in the coating solution is poor. The coating liquid did not diffuse smoothly on the irregularities of the predetermined pattern P on the wafer W. As a result, in the region S where the hole H of the pattern P is formed, the coating film R is recessed compared to the region T where the hole H of the pattern P is not formed, and the height of the coating film R is different, so-called step B. Has occurred. Therefore, the surface of the conventional coating film R is not flattened, and there is a problem that a step is generated in the resist film formed on the coating film R.

  The present invention has been made in view of this point, and an object of the present invention is to flatten the surface of a coating film when forming the coating film on a predetermined pattern formed on a substrate.

  In order to achieve the above object, the present invention provides a coating treatment method for forming a coating film on a pattern formed on a substrate, wherein the coating liquid for forming the coating film is a liquid coating film forming component and a solvent. The coating film forming component includes a photopolymerization initiator, and a coating step of coating the coating solution on the substrate pattern, and irradiating the coating solution coated on the substrate pattern with ultraviolet rays, And an irradiation step of forming a coating film by activating the photopolymerization initiator.

According to the present invention, the coating liquid containing the liquid coating film forming component is applied onto the pattern of the substrate. When the coating solution is applied onto the substrate pattern in this way, the coating solution diffuses smoothly over the irregularities of the substrate pattern because the liquid coating film forming component contained in the coating solution has good fluidity. can do. Therefore, no step is generated in the coating film formed on the pattern of the substrate, and the surface of the coating film can be planarized.
Further, here, the liquid coating film forming component contained in the coating liquid applied on the pattern of the substrate is a low molecule, and since each molecule is not bonded, it has the property of being easily sublimated. . When this coating film forming component is heated, the coating solution is further easily sublimated. Since the conventional coating film is formed by curing the coating liquid by heating the coating liquid, when using a coating liquid having a liquid coating forming component, the coating liquid sublimates when the coating liquid is cured. End up. However, according to the present invention, the coating liquid applied on the substrate pattern is irradiated with ultraviolet rays, the photopolymerization initiator contained in the coating film forming component in the coating liquid is activated to cure the coating liquid, Since the coating film is formed on the pattern of the substrate, heating of the coating solution is unnecessary or unnecessary, and it is not necessary to heat more than necessary, and sublimation of the coating solution can be suppressed as compared with the conventional case. When the photopolymerization initiator is irradiated with ultraviolet rays, the photopolymerization initiator is activated in a very short time, and the coating liquid can be cured in a short time. The activation of the photopolymerization initiator in a short time also contributes to suppression of sublimation of the coating solution. Thus, since sublimation of the coating liquid can be suppressed, a decrease in the film thickness of the formed coating film can be suppressed.

  The time from the end of the coating process to the start of the irradiation process may be controlled to be within a predetermined time. The predetermined time is set to a time during which the amount of sublimation of the applied coating solution falls within an allowable range when the substrate coated with the coating solution is left, for example. By controlling the time in this way, even if the coating liquid sublimates from the end of the coating process to the start of the irradiation process, the reduction in the thickness of the formed coating film can be kept within an allowable range. it can.

  Control may be performed so that the time from application of the coating liquid in the application process to irradiation of ultraviolet rays in the irradiation process is constant at all positions in the surface direction of the substrate. As a result, the amount of the applied coating solution to be sublimated can be made constant at all positions in the surface direction of the substrate to which the coating solution has been applied, so that the thickness of the formed coating film can be made constant.

  In the coating step, the coating solution on the region immediately after coating the coating solution on the region of the substrate may be irradiated with ultraviolet rays in the irradiation step. Thereby, since the coating liquid applied on the pattern of the substrate is cured by being irradiated with ultraviolet rays immediately after being applied to the substrate, the time from application of the coating liquid to irradiation of ultraviolet rays can be made minute, Sublimation of the coating solution can be suppressed.

  At least the coating step or the irradiation step may be performed by cooling the atmosphere around the substrate. As a result, the coating solution applied onto the pattern of the substrate is cooled, so that sublimation of the coating solution can be further suppressed.

After the coating process and before the irradiation process, heating the atmosphere around the substrate for a predetermined time to sublimate the coating liquid applied on the pattern of the substrate to a predetermined thickness You may have the process further.
Thus, after the coating liquid is applied onto the substrate pattern, if the applied coating liquid is thicker than the predetermined thickness, the atmosphere around the substrate is heated for a predetermined time to apply the substrate pattern coating liquid. By sublimating, the thickness of the coating solution can be set to a predetermined thickness. As a result, a coating film having a predetermined thickness can be formed. Although the thickness of the coating film can be controlled by the heating temperature and time as described above, the change in the large film thickness may be controlled by the temperature, and the change in the small film thickness may be controlled by the time. .
In addition, by heating the atmosphere around the substrate for a predetermined time in this way, it is possible to sublimate all the coating liquid applied to the surface of the pattern other than the concave portion of the pattern. That is, by setting the thickness of the coating film formed on the pattern to zero and filling and curing the coating liquid only in the concave portion of the pattern, the upper surface of the pattern can be flattened without the pattern irregularities. Conventionally, after forming a coating film, there is a case where a coating film on the pattern is not necessary, for example, etching is performed to remove the coating film, so-called etch back process is performed. The back process can be omitted, and the throughput of substrate processing can be improved.

After the irradiation step, the substrate may further include a heating step of heating the atmosphere around the substrate for a predetermined time and sublimating the coating film formed on the pattern of the substrate. For example, if the film thickness of the resist film formed on the coating film on the substrate pattern is not uniform or the resist film pattern is not desired, the substrate is peeled off from the resist film and the coating film. A so-called rework process may be performed in which a coating film and a resist film are re-formed on the pattern. The removal of the resist film and the coating film in the rework process has been conventionally performed by irradiating O ₂ plasma or N ₂ / H ₂ plasma. However, when irradiation with O ₂ plasma or the like is performed as in the past, the substrate pattern may be damaged by O ₂ plasma or the like. According to the present invention, in such a rework process, the coating film can be sublimated and peeled by heating the atmosphere around the substrate, so that damage to the pattern on the substrate can be reduced or eliminated. it can. This can also improve yield reduction during the rework process.

  The coating film may be a resist film for forming a pattern on the substrate. In such a case, the formed coating film can be used as a resist film, and the conventional step of forming a resist film can be omitted.

  According to another aspect of the present invention, there is provided a program that operates on a computer of a control unit that controls the substrate processing apparatus in order to cause the coating processing method to be executed by the substrate processing apparatus.

  According to another aspect of the present invention, a readable computer storage medium storing the above program is provided.

  According to the present invention, when forming a coating film on a predetermined pattern formed on a substrate, the surface of the coating film can be flattened, and the film thickness of the coating film can be reduced by suppressing sublimation of the coating liquid. Can be suppressed.

  Hereinafter, preferred embodiments of the present invention will be described. FIG. 1 is a plan view schematically showing the configuration of a coating and developing treatment system 1 equipped with a coating treatment apparatus for carrying out the coating treatment method according to the present embodiment, and FIG. FIG. 3 is a rear view of the coating and developing treatment system 1.

  As shown in FIG. 1, the coating and developing treatment system 1 is a cassette that carries, for example, 25 wafers W from the outside to the coating and developing treatment system 1 in a cassette unit, and carries a wafer W into and out of the cassette C. A station 2, a processing station 3 in which a plurality of various processing apparatuses for performing predetermined processing in a single wafer type in a photolithography process are arranged in multiple stages, and an exposure apparatus provided adjacent to the processing station 3 (Not shown) has a configuration in which the interface unit 4 for transferring the wafer W to and from the unit is integrally connected.

  The cassette station 2 is provided with a cassette mounting table 5 that can mount a plurality of cassettes C in a row in the X direction (vertical direction in FIG. 1). The cassette station 2 is provided with a wafer transfer body 7 that can move in the X direction on the transfer path 6. The wafer carrier 7 is also movable in the wafer arrangement direction (Z direction; vertical direction) of the wafers W accommodated in the cassette C, and is selective to the wafers W in each cassette C arranged in the X direction. Can be accessed.

  The wafer transfer body 7 is rotatable in the θ direction around the Z axis, and a temperature control device 60 belonging to a third processing device group G3 on the processing station 3 side to be described later, and a transition device 61 for delivering the wafer W. Can also be accessed.

  The processing station 3 adjacent to the cassette station 2 includes, for example, five processing device groups G1 to G5 in which a plurality of processing devices are arranged in multiple stages. A first processing device group G1 and a second processing device group G2 are arranged in this order from the cassette station 2 side on the X direction negative direction (downward direction in FIG. 1) side of the processing station 3. A third processing device group G3, a fourth processing device group G4, and a fifth processing device group G5 are sequentially arranged from the cassette station 2 side on the X direction positive direction (upward direction in FIG. 1) side of the processing station 3. Has been placed. A first transfer device A1 is provided between the third processing device group G3 and the fourth processing device group G4, and the wafer W is supported and transferred inside the first transfer device A1. A first transfer arm 10 is provided. The first transfer arm 10 can selectively access each processing apparatus in the first processing apparatus group G1, the third processing apparatus group G3, and the fourth processing apparatus group G4 to transfer the wafer W. A second transfer device A2 is provided between the fourth processing device group G4 and the fifth processing device group G5, and the wafer W is supported and transferred inside the second transfer device A2. A second transfer arm 11 is provided. The second transfer arm 11 can selectively access each processing apparatus in the second processing apparatus group G2, the fourth processing apparatus group G4, and the fifth processing apparatus group G5 to transfer the wafer W.

  As shown in FIG. 2, in the first processing unit group G1, a liquid processing apparatus that performs processing by supplying a predetermined liquid to the wafer W, for example, resist coating apparatuses 20, 21, and 22 that apply a resist solution to the wafer W. The bottom coating apparatus 23 for forming an antireflection film for preventing reflection of light during the exposure process, and the coating processing apparatus 24 for forming the coating film R on the pattern P of the wafer W according to the present invention are arranged in five stages in order from the bottom. It is piled up. In the second processing unit group G2, liquid processing units, for example, development processing units 30 to 34 that supply the developing solution to the wafer W and perform development processing are stacked in five stages in order from the bottom. In addition, chemical chambers 40 and 41 for supplying various processing liquids to the liquid processing apparatuses in the processing apparatus groups G1 and G2 are provided at the bottom of the first processing apparatus group G1 and the second processing apparatus group G2. Each is provided.

  For example, as shown in FIG. 3, the third processing unit group G3 includes a temperature control unit 60, a transition unit 61, high-precision temperature control units 62 to 64 that control the temperature of the wafer W under high-precision temperature control, and the wafer W. High-temperature heat treatment apparatuses 65 to 68 that heat-treat them at a high temperature are sequentially stacked in nine stages from the bottom.

  In the fourth processing unit group G4, for example, a high-accuracy temperature control unit 70, pre-baking units 71 to 74 that heat-treat the resist-coated wafer W, and post-baking units 75 to 74 that heat-process the developed wafer W. 79 are stacked in 10 steps from the bottom.

  In the fifth processing apparatus group G5, a plurality of heat treatment apparatuses for heat-treating the wafer W, for example, high-accuracy temperature control apparatuses 80 to 83 and post-exposure baking apparatuses 84 to 89 are stacked in 10 stages in order from the bottom.

  As shown in FIG. 1, a plurality of processing devices are arranged on the positive side in the X direction of the first transfer device A1, for example, the film thickness of the coating film applied to the wafer W as shown in FIG. A film thickness inspection device 95 to be inspected, adhesion devices 90 and 91 for hydrophobizing the wafer W, and heating devices 92 and 93 for heating the wafer W are stacked in five stages in order from the bottom. As shown in FIG. 1, for example, a peripheral exposure device 94 that selectively exposes only the edge portion of the wafer W, for example, is disposed on the positive side in the X direction of the second transfer device A2.

  For example, as shown in FIG. 1, the interface unit 4 is provided with a wafer transfer body 101 that moves on a transfer path 100 that extends in the X direction, and a buffer cassette 102. The wafer transfer body 101 can move in the Z direction and can also rotate in the θ direction. With respect to the exposure apparatus (not shown) adjacent to the interface unit 4, the buffer cassette 102, and the fifth processing apparatus group G5. The wafer W can be transferred by accessing.

  Next, the structure of the above-mentioned coating processing apparatus 24 is demonstrated based on FIG. The coating processing apparatus 24 includes a processing container 150 that can seal the inside. On one side of the processing container 150, a wafer W loading / unloading port 151 is formed on a surface facing the loading area of the first transfer arm 10 that is a transfer unit for the wafer W, and an opening / closing shutter 152 is provided at the loading / unloading port 151. It has been.

  Inside the processing container 150, a spin chuck 120 is provided as a substrate holding mechanism for vacuum suction holding the wafer W horizontally on its upper surface. The spin chuck 120 can be rotated around the vertical by a rotary drive unit 121 including a motor and can be moved up and down.

  A cup body 122 is provided around the spin chuck 120. An opening larger than the wafer W and the spin chuck 120 is formed on the upper surface of the cup body 122 so that the spin chuck 120 holding the wafer W can move up and down. At the bottom of the cup body 122, a drain port 123 for discharging the coating liquid that spills from the wafer W is formed, and a drain tube 124 is connected to the drain port 123.

  Above the spin chuck 120, a coating nozzle 130 for coating a coating solution on the center of the surface of the wafer W is disposed. The coating nozzle 130 is connected to a coating solution supply source 132 that supplies a coating solution via a coating solution supply pipe 131. Further, the coating liquid supply pipe 131 is provided with a supply control device 133 having a valve, a flow rate adjusting unit and the like. For example, XUV (Nissan Chemical Industry Co., Ltd. product) is used as the coating liquid supplied from the coating liquid supply source 132, and the coating liquid contains a liquid coating film forming component and a solvent. The coating film forming component includes, for example, a photopolymerization initiator such as an indonium salt, an epoxy resin, propylene glycol monomethyl ether, propylene glycol monoethyl acetate, and the like. For example, thinner is used as the solvent.

  An irradiation unit 110 that irradiates the wafer W on the spin chuck 120 with ultraviolet rays is provided above the processing container 150. The irradiation unit 110 can irradiate the entire surface of the wafer W with ultraviolet rays.

  The application nozzle 130 is connected to a moving mechanism 135 via an arm 134 as shown in FIG. The arm 134 is provided by the moving mechanism 135 on the outer side of one end side (left side in FIG. 5) of the cup body 122 along the guide rail 136 provided along the length direction (Y direction) of the processing container 150. It can move from the waiting area 137 toward the other end side and can move in the vertical direction. The standby region 137 is configured to store the application nozzle 130 and has a cleaning unit 137 a that can clean the tip of the application nozzle 130.

  The coating processing apparatus 24 includes a control unit 140 having a computer program that controls a series of operations described later. The control unit 140 is configured to control the irradiation unit 110, the rotation driving unit 121, the supply control device 133, the moving mechanism 135, and the like, and after the application of the coating liquid by the coating nozzle 130 is completed, the irradiation unit 110. Thus, the time until the start of ultraviolet irradiation is controlled to be within a predetermined time. Note that this predetermined time is set to a time during which the amount by which the applied coating solution sublimates is within an allowable range when the wafer W coated with the coating solution is left, for example, 20 seconds. The computer program is stored in a readable storage medium such as a hard disk (HD), a flexible disk (FD), a memory card, a compact disk (CD), a magnetic optical desk (MO), or a hard disk, and is the control unit 140. Installed on the computer.

  The coating and developing processing system 1 equipped with the coating processing apparatus 24 according to the present embodiment is configured as described above. Next, wafer processing performed in the coating and developing processing system 1 will be described.

  First, one wafer W having a predetermined pattern formed on the surface is taken out from the cassette C on the cassette mounting table 5 by the wafer transfer body 7 and transferred to the temperature adjustment device 60 of the third processing unit group G3. . The wafer W transferred to the temperature adjusting device 60 is adjusted to a predetermined temperature, and then transferred to the coating processing device 24 according to the present invention. In the coating processing apparatus 24, a coating film is formed on the pattern of the wafer W described later.

  When the coating film is formed on the pattern of the wafer W, the wafer W is transported to the bottom coating device 23 by the first transport arm 10 to form an antireflection film. The wafer W on which the antireflection film is formed is sequentially transferred by the first transfer arm 10 to the heating device 92, the high temperature heat treatment device 65, and the high precision temperature adjustment device 70, and is subjected to predetermined processing in each device. Thereafter, the wafer W is transferred to the resist coating apparatus 20.

  When a resist film is formed on the wafer W in the resist coating apparatus 20, the wafer W is transferred to the pre-baking apparatus 71 by the first transfer arm 10 and is subjected to heat treatment, and then the second transfer arm. 11 are sequentially conveyed to the peripheral exposure device 94 and the high-precision temperature adjustment device 83, and predetermined processing is performed in each device. Thereafter, the wafer is transferred to an exposure apparatus (not shown) by the wafer transfer body 101 of the interface unit 4, and a predetermined pattern is exposed on the resist film on the wafer W. The wafer W that has been subjected to the exposure process is transferred to the post-exposure baking apparatus 84 by the wafer transfer body 101 and subjected to a predetermined process.

  When the heat treatment in the post-exposure baking apparatus 84 is completed, the wafer W is transferred to the high-accuracy temperature adjustment apparatus 81 by the second transfer arm 11 and the temperature is adjusted, and then transferred to the development processing apparatus 30 and developed on the wafer W. Is applied to form a pattern on the resist film. Thereafter, the wafer W is transferred to the post-baking device 75 by the second transfer arm 11 and subjected to heat treatment, and then transferred to the high-accuracy temperature adjusting device 63 to adjust the temperature. Then, the wafer W is transferred to the transition device 61 by the first transfer arm 10 and returned to the cassette C by the wafer transfer body 7 to complete a series of photolithography steps.

  Next, a coating processing method for forming a coating film having a film thickness of, for example, 100 nm to 300 nm on the pattern of the wafer W performed in the coating processing apparatus 24 will be described. FIG. 6 shows a flow of a coating processing method for forming a coating film.

  The wafer W is transferred from the loading / unloading port 151 into the processing container 150 by the first transfer arm 10 and moved to above the spin chuck 120. Therefore, the spin chuck 120 is raised and the wafer W is delivered from the first transfer arm 10 to the spin chuck 120. Then, the wafer W is attracted to the spin chuck 120 and held horizontally, and the wafer W is lowered to a predetermined position.

  Next, the rotation drive unit 121 rotates the wafer W at, for example, a rotation speed of 500 rpm, and moves the coating nozzle 130 above the center of the wafer W (step S1). Then, as shown in FIG. 7A, the coating liquid Q is discharged from the coating nozzle 130 to the center of the wafer W for 2 seconds, for example, and the wafer W is accelerated to, for example, 1500 rpm and rotated for 15 seconds (step S2). . The coating liquid Q is diffused on the pattern P of the wafer W by the centrifugal force generated by the rotation of the wafer W. Thereafter, the coating nozzle 130 is moved from above the center of the wafer W to the standby area 137.

When the coating liquid Q is diffused over the entire surface of the pattern P of the wafer W, the wafer W is raised to a predetermined position by the spin chuck 120. Then, for example, ultraviolet light having a wavelength of 222 nm and an energy of 7 mW / cm ² is applied to the coating liquid Q applied on the pattern P of the wafer W from the irradiation unit 110, for example, for 2 seconds / cm ² (step S3). The photopolymerization initiator contained in the coating liquid Q is activated by the irradiated ultraviolet light, and the activated photopolymerization initiator diffuses to cure the coating liquid Q (step S4). Then, as shown in FIG. 7B, a coating film R formed by curing the coating liquid Q is formed on the pattern P of the wafer W (step S5).

  According to the above embodiment, when the coating liquid Q is applied onto the pattern P of the wafer W, the liquid coating film forming component contained in the coating liquid Q has good fluidity. Can smoothly diffuse on the irregularities of the pattern P of the wafer W. Therefore, as shown in FIG. 7B, the surface of the coating film R formed on the pattern P of the wafer W can be planarized.

  In addition, since the coating liquid Q is cured by irradiating the coating liquid Q applied on the pattern P of the wafer W from the irradiation unit 110 with the ultraviolet rays, the coating film R can be formed on the pattern P of the wafer W. Thus, it is not necessary to heat the coating liquid Q when forming the coating film R as in the prior art, and the sublimation of the coating liquid Q that is easily sublimated by heating can be suppressed as compared with the conventional case. Accordingly, it is possible to suppress a decrease in the thickness of the coating film R to be formed.

  When the photopolymerization initiator is irradiated with ultraviolet rays, the photopolymerization initiator is activated in a very short time, for example, 2 seconds, and the coating liquid Q is cured, so that sublimation of the coating liquid Q can be suppressed.

  Further, the control unit 140 controls the time from the end of the application of the coating liquid Q by the application nozzle 130 to the start of the irradiation of the ultraviolet rays by the irradiation unit 110 within a predetermined time, for example, within 20 seconds. The amount of coating liquid Q that sublimates from the end of application of coating liquid Q to the start of irradiation with ultraviolet rays can be kept within an allowable range, and the reduction in film thickness of formed coating film R is within the allowable range. Can be suppressed.

  In order to form a thin film on a large-diameter wafer, when the coating liquid is diffused on the wafer by rotating the wafer at a high speed, when the conventional coating liquid is used, the film thickness non-uniformity that is so-called air blown at the edge of the wafer Area has occurred. The cause of such wind-out is that the conventional coating liquid has a solid coating film forming component and a solvent, and when the coating liquid dries due to volatilization of the solvent during rotation of the wafer, the edge of the wafer This was because turbulent flow occurred. In this respect, since the coating liquid Q of the present embodiment has a liquid coating film forming component and the coating liquid Q is difficult to dry, such wind-off is unlikely to occur. Therefore, even if the wafer W is rotated at a high speed in order to form the thin coating film R on the wafer W, the film thickness of the coating film R to be formed can be made constant.

  Instead of the coating nozzle 130 described in the above embodiment, a coating nozzle 160 having a slit-like discharge port 160a extending in the X direction as shown in FIG. 8 may be used. The coating nozzle 160 is formed longer than the width of the wafer W in the X direction, for example, as shown in FIGS. The application nozzle 160 can move along the guide rail 136 from a standby region 161 provided outside one end side (left side in FIG. 10) of the cup body 122 toward the other end side. The standby area 161 is configured to accommodate the application nozzle 160.

  In this case, instead of the irradiation unit 110 provided on the upper portion of the processing container 150, an irradiation unit 170 extending in the X direction in parallel with the application nozzle 160 may be used as shown in FIG. The irradiation unit 170 is connected to the moving mechanism 172 via the arm 171. The arm 171 can be moved by the moving mechanism 171 along the guide rail 136 from the standby area 173 provided on the outer side of one end side (right side in FIG. 10) of the cup body 122 toward the other end side and in the vertical direction. I can move. The standby area 173 is configured to accommodate the irradiation unit 170.

  In such a case, the controller 140 adjusts the moving speed of the coating nozzle 160 and the irradiation unit 170 to apply the coating liquid Q by the coating nozzle 160 at all positions in the surface direction of the wafer W, and then the irradiation unit 170. Thus, it is possible to control the time until irradiation with ultraviolet rays to be constant. As a result, the amount of the applied coating liquid Q to be sublimated can be made constant at all positions in the surface direction of the wafer W coated with the coating liquid Q, so that the film thickness of the formed coating film R is made constant. be able to.

  Although the coating nozzle 160 and the irradiation unit 170 described in the above embodiment are provided independently, the irradiation unit 170 may be provided in the coating nozzle 160 as shown in FIG. According to the example of FIG. 11, the coating liquid Q on the area immediately after the coating liquid Q is applied onto the area of the wafer W can be irradiated with ultraviolet rays. As shown in FIG. 12, the irradiation unit 170 is connected to one side surface 160 a of the application nozzle 160 and one side surface 170 a of the irradiation unit 170. As a result, the coating liquid Q applied onto the pattern P of the wafer W is cured by being irradiated with ultraviolet rays immediately after being applied to the wafer W, so that the time from application of the coating liquid Q to irradiation of the ultraviolet rays is minimized. The sublimation of the coating liquid Q can be suppressed.

  The atmosphere around the wafer W on the spin chuck 120 may be cooled by further providing a gas supply unit 180 in the coating processing apparatus 24 of the above embodiment as shown in FIG. The gas supply unit 180 is provided in the upper part in the processing container 150. A plurality of holes (not shown) are formed in the lower surface of the gas supply unit 180, and gas is supplied downward from the plurality of holes. The gas supply unit 180 is connected to a gas supply source 182 that supplies gas via a gas supply pipe 181. The supply pipe 181 is provided with a temperature / humidity adjusting device 183 that adjusts the temperature and humidity of the supplied gas.

  In such a case, at least during application of the coating liquid Q onto the pattern P of the wafer W or during irradiation of the applied coating liquid Q with ultraviolet rays, the temperature / humidity adjusting device 183 causes the gas supply source 182 to The supplied gas is cooled, and the cooled gas can be supplied from the gas supply unit 180 toward the inside of the lower processing container 150. As a result, the inside of the processing container 150 is cooled to a temperature lower than room temperature, for example, 15 ° C. Thereby, the coating liquid Q applied on the pattern P of the wafer W is cooled, and sublimation of the coating liquid Q can be further suppressed.

  Further, after applying the coating liquid Q onto the pattern P of the wafer W using the coating processing apparatus 24 shown in FIG. 13 and before irradiating the applied coating liquid Q with ultraviolet rays, the wafer W The ambient atmosphere may be heated for a predetermined time.

  In such a case, first, the coating liquid Q is applied onto the pattern P of the wafer W by the coating nozzle 130 (FIG. 14A). Thereafter, the thickness of the applied coating solution Q is measured by the film thickness inspection device 95 shown in FIG. 3, and the measurement result is transmitted to the control unit 140. Based on the measurement result, the control unit 140 sublimates a part of the coating liquid Q so that the coating liquid Q has a predetermined thickness when the applied coating liquid Q is thicker than the predetermined thickness. Therefore, the atmosphere around the wafer W is controlled to be heated for a predetermined time. Specifically, the heating temperature and time are calculated so that the large thickness change is controlled by the heating temperature, and the small thickness change is controlled by the heating time. Then, the calculation result of the heating temperature and time is transmitted from the control unit 140 to the temperature / humidity adjusting device 183, and the gas supplied from the gas supply source 182 is heated by the temperature / humidity adjusting device 183. The heated gas is supplied from the gas supply unit 180 into the processing container 150, and the atmosphere around the wafer W is heated for a predetermined time. Then, a part of the coating solution Q on the pattern P of the wafer W is sublimated to make the coating solution Q have a predetermined thickness (FIG. 14B). Thereafter, when the coating solution Q remaining on the pattern P of the wafer W reaches a predetermined thickness, the coating solution Q is cured by irradiating the remaining coating solution Q with ultraviolet rays from the irradiation unit 110. (FIG. 14 (c)). Thereby, the coating film R having a predetermined film thickness can be formed on the pattern P of the wafer W.

  Further, by heating the atmosphere around the wafer W for a predetermined time in this way, it is also possible to sublimate all the coating liquid Q applied to the surface of the pattern P other than the concave portion of the pattern P of the wafer W (FIG. 15 (a)). That is, the thickness of the coating film R formed on the pattern P is made zero, and the coating liquid Q is filled and cured only in the concave portions of the pattern P, so that the unevenness of the pattern P is eliminated and the upper surface of the pattern P is flattened. (FIG. 15B). As a result, the etch-back process for removing the coating film R on the pattern P of the wafer W can be omitted, and the throughput of the wafer W process can be improved.

  For example, when the pattern of the resist film formed on the coating film R in the above embodiment is not a desired one, a rework process is performed on the wafer W, and the coating film R is formed by this rework process. At the time of peeling, the coating film R may be peeled off by heating the atmosphere around the wafer W.

In this case, first, the resist film pattern V and the antireflection film U formed on the coating film R are irradiated with, for example, O ₂ plasma to peel off the resist film pattern V and the antireflection film U (FIG. 17 ( a)). Then, the atmosphere around the wafer W is heated to 250 ° C. to 350 ° C. (FIG. 17B), and the coating film R is sublimated and peeled off (FIG. 17C). When the inventors investigated the sublimation of the coating film R, since the coating film R in the present invention has a low-molecular coating film forming component, the coating film R decomposes and sublimates at a temperature of 250 ° C. or higher. I found out that In consideration of the allowable temperature in the subsequent process (back-end process) of the wafer W processing, it is preferable to heat at a temperature of 350 ° C. or lower. Therefore, the heating temperature for sublimating the coating film R is preferably 250 ° C to 350 ° C.

In the above embodiment, since the coating film R is peeled off by heating, it is not necessary to use O ₂ plasma or the like as in the prior art, and damage to the pattern P on the wafer W can be reduced or eliminated. . Thereby, it is possible to improve the yield reduction during the rework processing of the wafer W.

  Further, the method of heating and peeling the coating film R in the above embodiment is also used when ashing the coating film R remaining on the pattern P after etching the wafer W using the resist film pattern V as a mask. It is valid. In such a case, the atmosphere around the wafer W is heated to 250 ° C. to 350 ° C. (FIG. 18A), and the coating film R is sublimated and peeled off (FIG. 18B). Thereby, the coating film R remaining on the pattern P can be ashed without damaging the pattern P on the wafer W.

  In the above embodiment, in the step of curing the coating liquid Q applied to the wafer W shown in steps S3 to S5 in FIG. 6, the coating liquid Q is crosslinked by irradiating the coating liquid Q with ultraviolet rays. The photopolymerization initiator that is directed toward the surface is activated, and the activated photopolymerization initiator is diffused to cure the coating liquid Q. In the step of diffusing the photopolymerization initiator, the diffusion of the photopolymerization initiator can be promoted by heating the coating liquid Q at a temperature of 100 ° C. to 130 ° C. Thus, in the curing step of the coating liquid Q in the present embodiment, the coating liquid Q is not cured by the heating energy itself as in the conventional case, but is heated at a temperature of 100 ° C. to 130 ° C. lower than the conventional heating temperature. And since the photoinitiator is diffused in a short time, the sublimation of the coating liquid Q can be suppressed conventionally. Therefore, the coating liquid Q can be cured efficiently.

  The coating film R formed in the above embodiment may be a resist film for forming the pattern P on the wafer W. The coating film R formed in this way can be used as a resist film, and the conventional step of forming a resist film can be omitted.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be made within the scope of the ideas described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs. The present invention is not limited to this example and can take various forms. The present invention can also be applied to a case where the substrate is another substrate such as an FPD (flat panel display) other than a wafer or a mask reticle for a photomask.

  Hereinafter, heating of the coating film of the present invention to sublimate the coating film will be described. In this example, a coating film having a film thickness of about 140 nm was formed on the wafer pattern by the method described in FIG. 6, and then the atmosphere around the wafer was heated at a temperature of 350 ° C.

  FIG. 19 shows the result of measuring the change with time of the thickness of the coating film after heating in this example. In FIG. 19, the vertical axis represents the average film thickness of the coating film, and the horizontal axis represents the heating time. Referring to FIG. 19, the thickness of the coating film was about 140 nm at the start of heating, but decreased to about 10 nm after about 60 seconds. Therefore, it was found that when the coating film of the present invention was heated at a predetermined temperature, for example, 350 ° C., the coating film sublimated.

  The present invention is useful for a coating processing method, a program, and a computer storage medium for forming a coating film on a pattern formed on a substrate.

1 is a schematic plan view of a configuration of a coating and developing treatment system equipped with a coating treatment apparatus according to the present embodiment. It is a front view of the coating and developing treatment system according to the present embodiment. It is a rear view of the coating and developing treatment system according to the present embodiment. It is a schematic longitudinal cross-sectional view of the structure of the coating processing apparatus concerning this Embodiment. It is a schematic plan view of the structure of the coating processing apparatus concerning this Embodiment. It is a flow which shows the formation method of the coating film concerning this Embodiment. It is explanatory drawing which shows the state of the coating film formed on the pattern of the wafer concerning this Embodiment. It is a perspective view of the application nozzle which has a slit-shaped discharge port. It is a schematic longitudinal cross-sectional view of the structure of the coating processing apparatus concerning another form. It is a schematic plan view of the structure of the coating processing apparatus concerning another form. It is a schematic plan view of the structure of the coating processing apparatus concerning another form. It is a perspective view in case an irradiation part is attached to the application nozzle. It is a schematic longitudinal cross-sectional view of the structure of the coating processing apparatus concerning another form. It is action explanatory drawing which shows typically the state of the coating liquid until a coating film is formed on the pattern of the wafer concerning another form. It is action explanatory drawing which shows typically the state of the coating liquid until a coating film is formed on the pattern of the wafer concerning another form. It is explanatory drawing which shows the state of the coating film formed on the pattern of the conventional wafer. It is an operation explanatory view showing a situation where a coating film on a wafer pattern and a resist film are peeled off during rework processing. It is operation | movement explanatory drawing which shows a mode that the coating film on the pattern of a wafer is ashed. In Example 1, it is a graph which shows the time-dependent change of the film thickness at the time of heating the coating film on the pattern of a wafer at 350 degreeC.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Application | coating development processing system 24 Application | coating processing apparatus 110 Irradiation part 120 Spin chuck 130 Application | coating nozzle 140 Control part 180 Gas supply part P Pattern Q Coating liquid R Coating film W Wafer

Claims (10)

A coating treatment method for forming a coating film on a pattern formed on a substrate,
The coating solution for forming the coating film includes a liquid coating film forming component and a solvent,
The coating film forming component contains a photopolymerization initiator,
A coating step of coating the coating liquid on the pattern of the substrate;
An irradiation step of irradiating the coating liquid applied on the pattern of the substrate with ultraviolet rays, activating the photopolymerization initiator to form a coating film,
A coating treatment method characterized by comprising: 2. The coating treatment method according to claim 1, wherein a time from the end of the coating process to the start of the irradiation process is controlled to be within a predetermined time. 3. The control is performed so that the time from when the coating liquid is applied in the coating step to when the ultraviolet rays are irradiated in the irradiation step is constant at all positions in the surface direction of the substrate. Or the coating processing method of 2. The ultraviolet ray in the said irradiation process is irradiated with respect to the coating liquid on the said area | region immediately after apply | coating a coating liquid on the area | region of a board | substrate in the said application | coating process, The any one of Claims 1-3 characterized by the above-mentioned. The coating process method of description. The coating treatment method according to claim 1, wherein at least the coating step or the irradiation step is performed by cooling an atmosphere around the substrate. After the application step and before the irradiation step,
The coating process according to claim 1, further comprising a heating step of heating an atmosphere around the substrate for a predetermined time and sublimating the coating liquid applied on the pattern of the substrate to a predetermined thickness. Method. 6. The method according to claim 1, further comprising a heating step of heating the atmosphere around the substrate for a predetermined time after the irradiation step to sublimate the coating film formed on the pattern of the substrate. The coating treatment method as described in 2. The coating method according to claim 1, wherein the coating film is a resist film for forming a pattern on a substrate. A program that operates on a computer of a control unit that controls the substrate processing apparatus in order to cause the substrate processing apparatus to execute the coating processing method according to claim 1. A readable computer storage medium storing the program according to claim 9.

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