JP5023171B2 - Coating processing method, recording medium recording program for executing coating processing method, and coating processing apparatus - Google Patents

Description

  The present invention relates to a coating processing method for coating a substrate with a coating liquid, a recording medium on which a program for executing the coating processing method is recorded, and a coating processing apparatus.

  In a photolithography process in a semiconductor device manufacturing process, for example, a predetermined resist pattern is formed by sequentially performing a coating process, an exposure process, a development process, and the like on a substrate such as a semiconductor wafer (hereinafter simply referred to as a “wafer”). Is formed. In the coating process, a resist solution is applied, and the applied resist solution is heat-treated to form a resist film. In the exposure process, the formed resist film is exposed to a predetermined pattern. In the development process, the exposed resist film is developed.

  In the above coating process, a resist solution is supplied from the nozzle to the center of the surface of the wafer that is rotating at high speed, and the resist solution is applied to the wafer surface by diffusing the resist solution to the outer peripheral side of the wafer by centrifugal force. A so-called spin coating method is often used. In the spin coating method, as a method of uniformly applying the resist solution, for example, a step of rotating the wafer at a high rotational speed, a step of temporarily reducing the rotational speed of the wafer, and a step of increasing the rotational speed of the wafer again. Has been proposed (see Patent Document 1). In the method disclosed in Patent Document 1, a wafer is rotated at a high rotational speed, and a resist solution is supplied to the surface of the wafer that rotates at a high rotational speed. Thereafter, the resist solution supplied to the surface of the wafer is planarized by once reducing the number of rotations of the wafer. Thereafter, by increasing the number of rotations of the wafer again, the resist solution flattened on the surface of the wafer is dried.

  A method in which the above-described method is changed has also been proposed (see Patent Document 2). In the method disclosed in Patent Document 2, the supply of the resist solution to the surface of the wafer is continued halfway through the process of once reducing the rotational speed, and when the supply of the resist solution is finished, Due to the movement, the supply position of the resist solution is shifted from the center of the wafer surface.

JP 2007-115936 A JP 2009-78250 A

  However, when a coating solution such as a resist solution is applied to the surface of the wafer by the coating process as described above, there are the following problems.

  When the resist solution is supplied to the center of the surface of the rotating wafer, the supplied resist solution is diffused to the outer peripheral side of the wafer by centrifugal force. However, according to the conventional method, as the resist solution diffuses to the outer peripheral side of the wafer, the amount of the resist solution per unit area on the outer periphery of the resist solution decreases, and sufficient centrifugal force cannot be obtained. . If sufficient centrifugal force cannot be obtained, the resist solution cannot diffuse to the outer periphery of the wafer surface. Therefore, the entire surface of the wafer cannot be covered with the resist solution.

  In order to coat the entire surface of the wafer with a resist solution in such a coating process, the amount of solution supplied to the surface of the wafer must be increased. Therefore, the amount of the resist solution necessary to coat the entire surface of the wafer with the resist solution cannot be reduced.

  Also, not only when applying a resist solution, but also when applying various kinds of coating solutions to be applied to the surface of a wafer, such as a solvent to be applied before applying a resist solution or a coating solution for forming an antireflection film. There are problems similar to those described above. That is, in the conventional coating process, the amount of coating solution required to coat the entire surface of the wafer with various coating solutions cannot be reduced.

  The present invention has been made in view of the above points, and when coating various coating liquids on the entire surface of the wafer, the amount of coating liquid necessary to coat the entire surface of the wafer with the coating liquid, A coating processing method and a coating processing apparatus that can be reduced are provided.

  In order to solve the above problems, the present invention is characterized by the following measures.

According to an embodiment of the present invention, the coating liquid is applied to the surface of the substrate by supplying the coating liquid to the surface of the rotating substrate and diffusing the supplied coating liquid to the outer peripheral side of the substrate. In the processing method, while the supply position for supplying the coating liquid to the surface of the rotating substrate is moved to the outer peripheral side in accordance with the movement of the coating liquid diffusing to the outer peripheral side, the coating liquid is supplied to the substrate. have a supply step of supplying a surface, said supplying step, the coating of the coating liquid supplied to the approximate center of the surface of the substrate rotating, the supplied the coating liquid is diffused into the outer peripheral side, diffuses Before the liquid reaches the outer periphery of the substrate, the rotation speed of the rotating substrate is maintained so as to be included in the surface of the substrate where the coating liquid is applied. From the approximate center toward the outer periphery To a predetermined position to move said supply position, a coating process wherein the is provided.

According to an embodiment of the present invention, the coating liquid is applied to the surface of the substrate by supplying the coating liquid to the surface of the rotating substrate and diffusing the supplied coating liquid to the outer peripheral side of the substrate. In the coating processing apparatus, a substrate holding unit that holds the substrate, a rotating unit that rotates the substrate holding unit that holds the substrate, and a surface of the substrate held by the substrate holding unit that is rotated by the rotating unit. a supply unit for supplying the coating liquid, a moving unit for moving the feed unit, the mobile unit, have a control unit for controlling the operation of the supply unit and the rotating unit, wherein the control unit, the supply The coating liquid is supplied to the approximate center of the surface of the substrate using a part, the coating liquid is diffused to the outer peripheral side using the rotating part, and the spreading coating liquid is diffused using the moving part. Before reaching the outer periphery of the substrate, the substrate The supply to the predetermined position from the approximate center of the surface of the substrate toward the outer peripheral side while maintaining the rotation number of the rotating substrate so that the surface is included in the region where the coating liquid is applied. An application processing apparatus is provided that moves the position .

  According to the present invention, when various coating liquids are applied to the entire surface of the wafer, the amount of the coating liquid necessary for coating the entire surface of the wafer with the coating liquid can be reduced.

It is a top view which shows the outline of a structure of the coating development processing system by which the coating processing apparatus which concerns on embodiment is mounted. It is a front view which shows the outline of a structure of a coating development processing system. It is a rear view which shows the outline of a structure of a coating and developing treatment system. It is explanatory drawing of the longitudinal cross-section which shows the outline of a structure of the resist coating device which concerns on embodiment. It is explanatory drawing of the cross section which shows the outline of a structure of a resist coating device. It is a flowchart which shows the main processes of the resist application | coating process which concerns on embodiment. It is a graph which shows the rotation speed of the wafer in each process of the resist coating treatment process which concerns on embodiment. It is a figure which shows the state of the surface of the wafer in each process of the resist application | coating process which concerns on embodiment. It is a figure which shows the state of the surface of the wafer in each process of the resist application | coating process which concerns on embodiment. It is a flowchart which shows the main processes of the resist application | coating process which concerns on a comparative example. It is a figure which shows the state of the surface of the wafer in each process of the resist coating process based on a comparative example. It is sectional drawing which shows typically distribution of the resist liquid which diffuses the surface of the wafer in the supply process which concerns on embodiment and a comparative example. It is a flowchart which shows the main processes of the resist application | coating process which concerns on the modification of embodiment. It is a graph which shows the rotation speed of the wafer in each process of the resist application | coating process which concerns on the modification of embodiment.

Next, a mode for carrying out the present invention will be described with reference to the drawings.
(Embodiment)
First, a coating treatment method and a coating treatment apparatus according to an embodiment will be described with reference to FIGS.

  First, a coating and developing treatment system equipped with a coating treatment apparatus according to the present embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a plan view showing an outline of the configuration of a coating and developing treatment system in which a coating treatment apparatus according to the present embodiment is mounted. FIG. 2 is a front view showing an outline of the coating and developing treatment system. FIG. 3 is a rear view showing an outline of the coating and developing treatment system.

  As shown in FIG. 1, the coating and developing treatment system 1 has a configuration in which, for example, a cassette station 2, a treatment station 3, and an interface station 4 are integrally connected. The cassette station 2 is for carrying in and out a plurality of wafers W from the outside to the coating and developing treatment system 1 in units of cassettes. The processing station 3 includes a plurality of various processing apparatuses that perform predetermined processing in a single-wafer manner during the photolithography process. The interface station 4 is adjacent to the processing station 3 and transfers the wafer W to and from the exposure apparatus 5.

  The cassette station 2 is provided with a cassette mounting table 10, and a plurality of cassettes C can be mounted on the cassette mounting table 10 in a row in the X direction (vertical direction in FIG. 1). The cassette station 2 is provided with a wafer transfer device 12 that can move on the transfer path 11 along the X direction. The wafer transfer device 12 is also movable in the arrangement direction (Z direction; vertical direction) of the wafers W accommodated in the cassette C, and can selectively access a plurality of wafers W in the cassette C. Further, the wafer transfer device 12 can rotate around a vertical axis (θ direction), and can access each processing device of a third processing device group G3 of the processing station 3 described later to transfer the wafer W. .

  The processing station 3 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 sequentially arranged from the cassette station 2 side to the interface station 4 side on the X direction negative direction (downward direction in FIG. 1) side of the processing station 3. Has been. On the positive side of the processing station 3 in the X direction (upward in FIG. 1), the third processing device group G3, the fourth processing device group G4, and the fifth processing device group G3 are directed from the cassette station 2 side to the interface station 4 side. The processing device group G5 is arranged in order. A first transfer device 20 is provided between the third processing device group G3 and the fourth processing device group G4. The first transfer device 20 can selectively access each device in the first processing device group G1, the third processing device group G3, and the fourth processing device group G4 to transfer the wafer W. A second transport device 21 is provided between the fourth processing device group G4 and the fifth processing device group G5. The second transfer device 21 can selectively access each device in the second processing device group G2, the fourth processing device group G4, and the fifth processing device group G5 to transfer the wafer W.

  As shown in FIG. 2, the first processing unit group G1 includes a liquid processing unit that performs processing by supplying a predetermined liquid to the wafer W, such as resist coating units (COT) 30, 31, 32, and a bottom coating unit. (BARC) 33 and 34 are stacked in five stages in order from the bottom. The bottom coating apparatuses 33 and 34 form an antireflection film for preventing reflection of light during the exposure process.

  The resist coating apparatuses 30, 31, and 32 correspond to the coating processing apparatus in the present invention.

  In the second processing unit group G2, liquid processing units, for example, development processing units (DEV) 40 to 44 are stacked in five stages in order from the bottom. The development processing devices 40 to 44 are for supplying a developing solution to the wafer W for development processing.

  Chemical chambers (CHM) 50 and 51 are respectively provided in the lowermost stages of the first processing device group G1 and the second processing device group G2. The chemical chambers 50 and 51 supply various processing liquids to the liquid processing apparatuses in the processing apparatus groups G1 and G2.

  As shown in FIG. 3, the third processing device group G3 includes a temperature control device (CPL) 60, a transition device (TRS) 61, temperature control devices (CPL) 62 to 64, and a heat processing device (BAKE) 65 to 65. 68 are stacked in nine steps from the bottom. The temperature control devices 60 and 62 to 64 adjust the temperature of the wafer W by placing the wafer W on a temperature control plate. The transition device 61 is for transferring the wafer W. The heat treatment apparatuses 65 to 68 heat the wafer W.

  In the fourth processing device group G4, for example, a temperature control device (CPL) 70, pre-baking devices (PAB) 71 to 74, and post-baking devices (POST) 75 to 79 are stacked in 10 stages in order from the bottom. The pre-baking apparatuses 71 to 74 heat the wafer W after the resist coating process. The post-bake devices 75 to 79 heat the wafer W after the development processing.

  In the fifth processing apparatus group G5, a plurality of heat processing apparatuses for heat-treating the wafer W, for example, temperature control apparatuses (CPL) 80 to 83 and post-exposure baking apparatuses (PEB) 84 to 89 are stacked in 10 stages in order from the bottom. ing. The post-exposure baking apparatuses 84 to 89 heat the wafer W after the exposure.

  As shown in FIGS. 1 and 3, a plurality of processing devices, for example, adhesion devices (AD) 90 and 91 are stacked in two stages from the bottom on the positive side in the X direction of the first transport device 20. . The adhesion devices 90 and 91 are for hydrophobizing the wafer W. In addition, for example, a peripheral exposure device (WEE) 92 is arranged on the positive side in the X direction of the second transport device 21. The peripheral exposure apparatus 92 selectively exposes only the edge portion of the wafer W.

  As shown in FIG. 1, the interface station 4 is provided with, for example, a wafer transfer device 101 and a buffer cassette 102. Wafer transfer apparatus 101 moves on transfer path 100 extending in the X direction. Further, the wafer transfer apparatus 101 is movable in the Z direction and is also rotatable in the θ direction. The wafer transfer apparatus 101 is provided in the exposure apparatus 5 adjacent to the interface station 4, the buffer cassette 102, and the fifth processing apparatus group G5. On the other hand, the wafer W can be transferred by accessing.

  The exposure apparatus 5 in the present embodiment performs, for example, immersion exposure processing. The liquid film of pure water, for example, a liquid film of pure water is retained on the surface of the wafer W. The resist film on the surface of the wafer W can be exposed through the interposition.

  Next, with reference to FIG.4 and FIG.5, the structure of the resist coating apparatuses 30-32 which concern on this Embodiment is demonstrated. FIG. 4 is an explanatory view of a longitudinal section showing an outline of the configuration of the resist coating apparatus, and FIG. 5 is an explanatory view of a transverse section showing an outline of the configuration of the resist coating apparatus.

  For example, as shown in FIG. 4, the resist coating apparatus 30 includes a casing 120, and a spin chuck 130 that holds the wafer W is provided in the center of the casing 120. The spin chuck 130 has a horizontal upper surface, and a suction port (not shown) for sucking the wafer W, for example, is provided on the upper surface. By suction from the suction port, the wafer W can be sucked and held on the spin chuck 130.

  The spin chuck 130 has a chuck drive mechanism 131 including a motor, for example, and can be rotated at a predetermined speed by the chuck drive mechanism 131. Further, the chuck drive mechanism 131 is provided with an elevating drive source such as a cylinder, and the spin chuck 130 can move up and down.

  The spin chuck 130 corresponds to the substrate holding part in the present invention, and the chuck driving mechanism 131 corresponds to the rotating part in the present invention.

  Further, the number of rotations of the spin chuck 130 driven by the chuck driving mechanism 131 is controlled by a control unit 160 described later.

  Around the spin chuck 130, a cup 132 that receives and collects the liquid scattered or dropped from the wafer W is provided. A discharge pipe 133 that discharges the collected liquid and an exhaust pipe 134 that exhausts the atmosphere in the cup 132 are connected to the lower surface of the cup 132.

  As shown in FIG. 5, a rail 140 extending along the Y direction (left and right direction in FIG. 5) is formed on the X direction negative direction (downward direction in FIG. 5) side of the cup 132. The rail 140 is formed, for example, from the outside of the cup 132 in the Y direction negative direction (left direction in FIG. 5) to the outside in the Y direction positive direction (right direction in FIG. 5). For example, two arms 141 and 142 are attached to the rail 140.

  As shown in FIGS. 4 and 5, a resist solution nozzle 143 that discharges a resist solution as a coating solution is supported on the first arm 141. The first arm 141 is movable on the rail 140 by a nozzle driving unit 144 shown in FIG. As a result, the resist solution nozzle 143 can move from the standby unit 145 installed on the outer side of the cup 132 on the positive side in the Y direction to substantially above the center of the wafer W in the cup 132, and further on the surface of the wafer W. It can move in the radial direction of the wafer W. The first arm 141 can be moved up and down by a nozzle driving unit 144 and the height of the resist solution nozzle 143 can be adjusted.

  The resist nozzle 143 corresponds to the supply unit in the present invention, and the first arm 141 and the nozzle drive unit 144 correspond to the moving unit in the present invention.

  As shown in FIG. 4, a supply pipe 147 communicating with the resist solution supply source 146 is connected to the resist solution nozzle 143. The resist solution supply source 146 in the present embodiment stores a low-viscosity resist solution for forming a thin resist film, for example, a resist film of 150 nm or less. The supply pipe 147 is provided with a valve 148. By opening and closing the valve 148, the discharge of the resist solution can be turned ON / OFF.

  The second arm 142 supports a solvent nozzle 150 that discharges the solvent of the resist solution. The second arm 142 is movable on the rail 140 by, for example, a nozzle driving unit 151 shown in FIG. 5, and the solvent nozzle 150 is moved from a standby unit 152 provided on the outer side of the cup 132 on the Y direction negative direction side. It is possible to move the wafer W up to substantially the center of the wafer W in the cup 132. Further, the second arm 142 can be moved up and down by the nozzle driving unit 151, and the height of the solvent nozzle 150 can be adjusted.

  As shown in FIG. 4, a supply pipe 154 communicating with a solvent supply source 153 is connected to the solvent nozzle 150. In the above configuration, the resist solution nozzle 143 that discharges the resist solution and the solvent nozzle 150 that discharges the solvent are supported by separate arms. However, the resist solution nozzle 143 and the solvent nozzle 150 may be provided to be supported by the same arm, and the movement and discharge timing of the resist solution nozzle 143 and the solvent nozzle 150 are controlled by controlling the movement of the arm. Also good.

  The rotation operation of the spin chuck 130 by the chuck driving mechanism 131 is controlled by the control unit 160. The controller 160 also controls the movement of the resist solution nozzle 143 by the nozzle drive unit 144 and the ON / OFF operation of the resist solution nozzle 143 by the valve 148 for discharging the resist solution. In addition, the operation of the drive system such as the movement of the solvent nozzle 150 by the nozzle drive unit 151 is also controlled by the control unit 160. The control unit 160 is configured by, for example, a computer including a CPU, a memory, and the like. For example, the resist coating process in the resist coating apparatus 30 can be realized by executing a program stored in the memory.

  As will be described later, the control unit 160 causes the nozzle driver 144 to move the resist solution nozzle 143 to the outer peripheral side of the wafer W while moving the resist solution nozzle 143 to the outer peripheral side of the wafer W. A resist solution is supplied to the surface of the wafer W by the nozzle 143.

  The various programs for realizing the resist coating process in the resist coating apparatus 30 are recorded on a recording medium such as a computer-readable CD, and are installed in the control unit 160 from the recording medium. Things are used.

  Note that the configuration of the resist coating apparatuses 31 and 32 is the same as that of the above-described resist coating apparatus 30, and thus the description thereof is omitted.

  Next, a resist coating process performed by the resist coating apparatus 30 configured as described above will be described together with a wafer processing process performed by the entire coating and developing system 1 with reference to FIGS. FIG. 6 is a flowchart showing main steps of the resist coating process according to the present embodiment. FIG. 7 is a graph showing the number of wafer rotations in each step of the resist coating process according to the present embodiment. 8 and 9 are views showing the state of the surface of the wafer in each step of the resist coating process according to the present embodiment.

  The resist coating process corresponds to the coating method in the present invention.

  As shown in FIGS. 6 and 7, the resist coating process in the present embodiment includes a solvent nozzle moving step (step S11), a solvent supplying step (step S12), a resist solution nozzle moving step (step S13), and solvent diffusion. It has a process (step S14), a supply process (steps S15 to S17), a first rotation process (step S18), a second rotation process (step S19), and a rotation stop process (step S20). The supply process includes a center supply process (step S15), a movement start process (step S16), and a movement supply process (step S17).

  Table 1 shows an example of a recipe that is a program for executing the resist coating process in the resist coating apparatus 30 when performing the resist coating process according to the present embodiment and that is controlled by the control unit 160.

表１において、左側から右側にかけての各列は、ステップ、時間、回転数、ウェハの中心を基準としたときのノズル位置、供給される塗布液を示している。

In Table 1, each column from the left side to the right side indicates a step, time, number of rotations, nozzle position with reference to the center of the wafer, and the supplied coating liquid.

  First, unprocessed wafers W are taken out from the cassette C on the cassette mounting table 10 one by one by the wafer transfer device 12 shown in FIG. 1 and sequentially transferred to the processing station 3. The wafer W is transferred to the temperature control device 60 belonging to the third processing device group G3 of the processing station 3, and the temperature is adjusted to a predetermined temperature. Thereafter, the wafer W is transferred to, for example, the bottom coating device 34 by the first transfer device 20 to form an antireflection film. The wafer W on which the antireflection film is formed is successively transferred by the first transfer device 20 to, for example, the heat treatment device 65 and the temperature control device 70, and predetermined processing is performed in each processing device. The wafer W that has been subjected to the predetermined processing is transferred to, for example, the resist coating apparatus 30 by the first transfer apparatus 20. As shown in FIG. 4, the wafer W transferred to the resist coating apparatus 30 is sucked and held by the spin chuck 130, and the resist coating process in the present embodiment is performed.

  First, a solvent nozzle moving step (step S11) is performed. In the solvent nozzle moving step (step S <b> 11), the nozzle nozzle 151 moves the solvent nozzle 150 from the standby unit 152. Then, as shown in FIG. 8A, the solvent nozzle 150 is moved onto the center PC of the wafer W.

  Next, a solvent supply process (step S12) is performed. In the solvent supply step (step S12), the solvent PW made of, for example, thinner is supplied to the center PC on the surface of the wafer W. As shown in FIG. 8B, for example, in a state where the wafer W is stopped, a predetermined amount of the solvent PW is discharged from the solvent nozzle 150, and the solvent PW is supplied to the center PC on the surface of the wafer W.

  The “center PC” means the rotation center of the wafer W held on the spin chuck 130 and driven to rotate by the chuck drive mechanism 131. “Supply to the central PC” includes a case where the power is not strictly supplied to the central PC, for example, a case where the power is supplied to a point separated from the central PC by a minute distance. Therefore, it is sufficient to supply to substantially the center. The same applies not only when the solvent PW is supplied but also when the resist solution R is supplied.

  Next, a resist solution nozzle moving step (step S13) is performed. In the resist solution nozzle moving step (step S <b> 13), the nozzle drive unit 151 moves the solvent nozzle 150 to the standby unit 152, and the nozzle drive unit 144 moves the resist solution nozzle 143 from the standby unit 145. Then, the resist solution nozzle 143 is moved onto the center PC of the wafer W as shown in FIG.

  Next, a solvent diffusion process (step S14) is performed. In the solvent diffusion step (step S14), the solvent PW is diffused to the outer peripheral side of the wafer W by rotating the wafer W. As shown in FIG. 8D, the wafer W held on the spin chuck 130 is rotated at a predetermined rotational speed VP by the chuck driving mechanism 131 for a predetermined time TP. Here, as an example, as shown in FIG. 7 and Table 1, the predetermined time TP can be set to 0.3 seconds, for example, and the predetermined rotation speed VP can be set to 2000 rpm, for example. As a result, the supplied solvent PW is diffused over the entire surface of the wafer W by centrifugal force. Then, the solvent PW is applied to the surface of the wafer W.

  Next, a supply process (step S15-step S17) is performed.

  First, a center supply process (step S15) is performed. In the center supply step (step S15), the resist solution R is supplied to the center PC on the surface of the rotating wafer W, and the supplied resist solution R is diffused to the outer peripheral side of the wafer W.

  The wafer W held on the spin chuck 130 is rotated by the chuck drive mechanism 131 at a predetermined rotation speed VS1. Here, the predetermined rotational speed VS1 can be set to, for example, 1500 to 4000 rpm, and more preferably, for example, 2000 rpm as shown in Table 1. For example, when both the predetermined rotation speeds VP and VS1 are 2000 rpm, the rotation speed does not change between the solvent diffusion process (step S14) and the center supply process (step S15).

  Then, in a state where the resist solution nozzle 143 that has moved onto the center PC of the wafer W is stationary, the valve 148 is opened to start discharging the resist solution R from the resist solution nozzle 143. As a result, as shown in FIG. 9A, the resist solution R starts to be supplied to the center PC on the surface of the wafer W by the resist solution nozzle 143 moved onto the center PC of the wafer W. Then, the supplied resist solution R starts to diffuse from the center PC on the surface of the wafer W to the outer peripheral side by centrifugal force.

  In the present embodiment, as the resist solution R, for example, one having a viscosity of 2 cp or less for thin film coating is used.

  By performing the center supply process (step S15) for a predetermined time TS1, the supplied resist solution R diffuses partway toward the outer periphery of the wafer W on the surface of the wafer W. Therefore, the diffusing resist solution R does not reach the outer periphery of the wafer W. Here, as an example, as shown in Table 1, the predetermined time TS1 can be set to 1.0 second, for example.

  The resist solution nozzle 143 only needs to move on the center PC of the wafer W and does not have to be stationary. For example, it may be finely moved or reciprocated on the center PC of the wafer W.

  Next, a movement start process (step S16) is performed. In the movement start process (step S <b> 16), the resist solution nozzle 143 starts to move from the center PC of the wafer W toward the outer periphery of the wafer W before the diffusing resist solution R reaches the outer periphery of the wafer W. That is, before the diffusing resist solution R reaches the outer periphery of the wafer W, the supply position for supplying the resist solution R to the surface of the wafer W starts to move toward the outer periphery of the wafer W.

  As shown in FIG. 9B, the wafer W held on the spin chuck 130 is rotated at a predetermined rotation speed VS1 by the chuck driving mechanism 131, and the resist solution nozzle 143 is moved to the wafer W by the nozzle driving unit 144. Start moving from the center PC toward the outer peripheral side. In the central supply process (step S15), which is the immediately preceding process, the diffusing resist solution R has reached the middle of the outer periphery of the surface of the wafer W, and in this state, the process proceeds to the movement start process (step S16). Therefore, in the movement start step (step S16), the resist solution nozzle 143 starts to move before the diffusing resist solution R reaches the outer periphery of the wafer W.

  Subsequent to the movement start process (step S16), a movement supply process (step S17) is performed. In the movement supply step (step S17), the resist solution R is moved while moving the resist solution nozzle 143 from the center PC of the wafer W to the outer periphery side in accordance with the movement of the resist solution R diffusing to the outer periphery side of the wafer W. Supply to the surface of the wafer W.

  As shown in FIG. 9C, the wafer W held on the spin chuck 130 is rotated at a predetermined rotation speed VS2 by the chuck driving mechanism 131, and the resist solution nozzle 143 is moved to the wafer W by the nozzle driving unit 144. Is moved from the center PC to a predetermined position P on the outer periphery side for a predetermined time TS2. Then, the resist solution R is supplied to the surface of the wafer W by discharging the resist solution R while moving the resist solution nozzle 143.

  Here, the predetermined rotational speed VS2 can be set to, for example, 1500 to 4000 rpm, and more preferably, for example, 2000 rpm as shown in Table 1. For example, when both the predetermined rotation speeds VS1 and VS2 are 2000 rpm, the rotation speed does not change between the center supply process (step S15) and the movement supply process (step S17).

  In the moving supply process (step S17), the supply position PS where the resist solution R is supplied from the resist solution nozzle 143 to the surface of the wafer W is the surface AR of the wafer W where the resist solution R is applied. In order to be included, the supply position PS is moved to a predetermined position P in a predetermined time TS2. That is, the nozzle driver 144 moves the resist solution nozzle 143 from the center PC of the wafer W to the outer peripheral side so that the supply position PS described above is included in the area AR where the resist solution R is applied on the surface of the wafer W. Move towards.

  When the resist solution nozzle 143 discharges the resist solution R substantially vertically and downward, and the moving speed of the resist solution nozzle 143 is not so high, the position of the resist solution nozzle 143 in plan view and the supply position PS Is almost identical.

  As an example when the predetermined rotational speed VS2 is set to 2000 rpm, for example, as shown in FIG. 7 and Table 1, the predetermined time TS2 is set to 0.4 seconds, for example, and the center PC of the wafer W is set as a reference, that is, 0. The predetermined position P can be set to 50 mm, for example.

  Note that the supply position PS is included in the area AR where the resist solution R is applied means that the supply position PS is diffused to the surface of the wafer W at the tip (outer periphery) FL, that is, behind the outermost periphery, that is, behind the outermost periphery. It means that it is on the inner circumference side. In other words, it means that the resist solution nozzle 143 does not pass the tip (outer periphery) FL of the diffusing resist solution R.

  In this manner, the resist solution nozzle 143 (supply position PS) is moved from the center PC of the wafer W toward the predetermined position P on the outer peripheral side, so that the diffusing resist solution R reaches the outer periphery of the wafer W. Further, as will be described later, when the resist solution R is applied to the entire surface of the wafer W, the amount of the resist solution R required to coat the entire surface of the wafer W with the resist solution R can be reduced.

  In FIG. 7 and Table 1, the predetermined rotation speeds VS1 and VS2 in the supply process (steps S15 to S17) are constant and equal to each other, and are also equal to the rotation speed VP in the solvent diffusion process (step S14). Shows about. However, the predetermined rotation speeds VS1 and VS2 in the supply process (steps S15 to S17) may not be constant and may not be equal to each other. Further, the predetermined rotational speeds VS1 and VS2 in the supply process (steps S15 to S17) may not be equal to the rotational speed VP in the solvent diffusion process (step S14).

  Next, a 1st rotation process (step S18) is performed. In the first rotation process (step S18), the first rotation speed lower than the rotation speed at which the wafer W rotates when the supply process is completed in a state where the supply of the resist liquid R from the resist liquid nozzle 143 is stopped. The wafer W is rotated at V1 for a predetermined time T1. FIG. 9D shows the state of the wafer W in the first rotation process (step S18) and the second rotation process (step S19).

  By performing the first rotation process (step S18), the resist solution R on the wafer W is leveled. That is, the resist solution R is flattened. The first rotation speed V1 can be set to, for example, 100 to 1000 rpm, and more preferably, for example, to 100 rpm as shown in Table 1.

  As described above, as an example, the case where the predetermined rotation speeds VS1 and VS2 in the supply process (steps S15 to S17) are constant and equal to each other is described. Therefore, the wafer W at the end of the supply process is described. The rotation speed is VS2. Therefore, by setting the first rotation speed V1 to 100 rpm, the first rotation speed V1 can be made lower than the rotation speed VS2 of the wafer W when the supply process is completed. Further, the predetermined time T1 can be set to 1.0 second, for example.

  Next, a second rotation process (step S19) is performed. In the second rotation step (step S19), the wafer W is rotated for a predetermined time T2 at a second rotation speed V2 higher than the first rotation speed V1. Thereby, the resist solution R applied on the wafer W is dried. Thereby, a thin resist film is formed on the wafer W.

  Here, the second rotational speed V2 can be set to, for example, 1000 to 2000 rpm, and more preferably, for example, to 1700 rpm as shown in Table 1. Further, the predetermined time T2 can be set to 17 seconds, for example.

  Finally, a rotation stop process (step S20) is performed. In the rotation stop process (step S20), the rotation of the wafer W is stopped. After the drying of the wafer W is completed, the rotation of the wafer W is stopped.

  Further, after the rotation stop process (step S20), the wafer W is unloaded from the spin chuck 130. In this way, a series of resist coating process is completed.

  After the resist coating process, the wafer W is transferred to the pre-baking device 71 by the first transfer device 20 and pre-baked, for example. Subsequently, the wafer W is sequentially transferred to the peripheral exposure device 92 and the temperature control device 83 by the second transfer device 21 and subjected to predetermined processing in each device. Thereafter, the wafer W is transferred to the exposure apparatus 5 by the wafer transfer apparatus 101 of the interface station 4 and subjected to immersion exposure. Thereafter, the wafer W is transferred to, for example, a post-exposure bake device 84 by the wafer transfer device 101, baked after exposure, and then transferred to the temperature adjustment device 81 by the second transfer device 21 to adjust the temperature. Thereafter, the wafer W is transferred to the development processing apparatus 40, and the resist film on the wafer W is developed. After development, the wafer W is transferred to the post-baking device 75 by the second transfer device 21 and post-baked. Thereafter, the wafer W is transferred to the temperature control device 63 and the temperature is adjusted. Then, the wafer W is transferred to the transition device 61 by the first transfer device 20 and returned to the cassette C by the wafer transfer device 12. In this way, a series of wafer processing is completed.

  Next, referring to FIG. 10 to FIG. 12, the amount of the resist solution R required to coat the entire surface of the wafer W with the resist solution R can be reduced by the resist coating process according to the present embodiment. It demonstrates by comparing with a comparative example. FIG. 10 is a flowchart showing main steps of the resist coating process according to the comparative example. FIG. 11 is a diagram illustrating the state of the surface of the wafer in each step of the resist coating process according to the comparative example. FIG. 12 is a cross-sectional view schematically showing the distribution of the resist solution that diffuses the surface of the wafer in the supplying step according to the present embodiment and the comparative example. 12A shows the distribution of the resist solution in the present embodiment, and FIG. 12B shows the distribution of the resist solution in the comparative example. In FIG. 12, the illustration of the solvent PW is omitted.

  As shown in FIG. 10, the resist coating process in the comparative example includes the solvent nozzle moving process (step S11) to the center supplying process (steps) among the processes of the resist coating process according to the present embodiment shown in FIG. After performing S15), a movement start process (step S16) and a movement supply process (step S17) are abbreviate | omitted, and a 1st rotation process (step S18) and subsequent steps are performed. Therefore, in the comparative example, the supply process includes only the center supply process (step S15).

  Table 2 shows an example of a recipe when performing the resist coating process according to the comparative example.

表２においても、表１と同様に、左側から右側にかけての各列は、ステップ、時間、回転数、ウェハの中心を基準としたときのノズル位置、供給される塗布液を示している。

Also in Table 2, as in Table 1, each column from the left side to the right side shows the step, time, rotation speed, nozzle position with reference to the center of the wafer, and the supplied coating liquid.

  In the recipe shown in Table 2, the moving supply process (step S17) shown in FIG. 7 and Table 1 is omitted.

  In the resist coating process according to the comparative example, the state of the surface of the wafer W in each process from the solvent nozzle moving process (step S11) to the solvent diffusion process (step S14) is the same as the resist coating process according to the present embodiment. Similarly, FIG. 8A to FIG. 8D are shown.

  On the other hand, the state of the surface of the wafer W in each step after the center supply step (step S15) is shown in FIG. 11 (a) to FIG. 11 (d).

  In the center supply step (step S15), the resist solution R is supplied to the center PC on the surface of the rotating wafer W, as in the present embodiment. Further, the state at this time is sequentially shown in FIGS. 11A to 11C.

  The resist solution R supplied to the center PC on the surface of the wafer W is diffused to the outer peripheral side of the wafer W by centrifugal force. As the resist solution R diffuses to the outer peripheral side of the wafer W, the amount of the resist solution R per unit area at the tip (outer periphery) FL of the diffusing resist solution R decreases, and the tip (outer periphery) FL. The resist solution R becomes easy to dry. When the resist solution R is dried at the tip (outer periphery) FL, the resist per unit area at the tip (outer periphery) FL of the diffusing resist solution R is shown in a region II surrounded by a broken line in FIG. The amount of the liquid R is further reduced. If the amount of the resist solution R per unit area at the front end (outer periphery) FL decreases, a sufficient centrifugal force cannot be obtained, so that the resist solution R cannot reach the outer periphery of the wafer W. As a result, the entire surface of the wafer W cannot be covered with the resist solution R as shown in FIG.

  On the other hand, according to this Embodiment, a supply process has a movement supply process (step S17). In the moving supply step (step S17), the resist solution nozzle 143 is moved so that the supply position PS is on the surface of the wafer W and is included in the region AR where the resist solution R is applied, and the resist solution R is diffused. Is moved from the center PC of the wafer W to the outer peripheral side. As a result, the resist solution R can be supplied to a position closer to the inner periphery than the tip (outer periphery) FL of the diffusing resist solution R and near the tip (outer periphery) FL. When the resist solution R is supplied to a position near the tip (outer periphery) FL, as shown in a region I surrounded by a broken line in FIG. The amount of the resist solution R per unit area at the tip (outer periphery) FL is larger than that in the comparative example. Further, when the amount of the resist solution R per unit area at the front end (outer periphery) FL increases, it is possible to prevent the liquid amount from being reduced by drying the resist solution R at the front end (outer periphery) FL. Accordingly, a sufficient centrifugal force can be obtained even at the tip (outer periphery) FL of the resist solution R, and the diffusing resist solution R can reach the outer periphery of the surface of the wafer W. As a result, even when a liquid amount equal to that of the comparative example is supplied as a total, the entire surface of the wafer W can be covered with the resist liquid R as shown in FIG. That is, the amount of liquid that can cover the entire surface of the wafer W with the resist liquid R can be reduced as compared with the comparative example.

  In the present embodiment, in the movement start step (step S16), before the diffusing resist solution R reaches the outer periphery of the wafer W, the resist solution nozzle 143 starts to move toward the outer periphery. As a result, even a small amount of resist solution R that cannot reach the outer periphery of the wafer W only by the center supply step (step S15) can reach the outer periphery of the wafer W. Therefore, the amount of the resist solution R required to coat the entire surface of the wafer W with the resist solution R can be reduced.

  Further, in the present embodiment, since the resist solution R is supplied so that the supply position PS is on the surface of the wafer W and is included in the region AR applied with the resist solution R, the supply position PS is diffused. The tip (outer periphery) FL of the liquid R is not overtaken. Therefore, the area AR to which the resist solution R is applied can be expanded to the outer peripheral side while maintaining a substantially circular shape, and the resist solution R can be uniformly applied along the rotation direction.

  Actually, using a wafer having a diameter of 300 mmφ and changing the amount of the resist solution R, the resist according to this embodiment is based on the recipes in Table 1 (this embodiment) and Table 2 (comparative example). Experiments were conducted to demonstrate the effectiveness of the coating process. As a result, in the comparative example, the amount of the resist solution R required to cover the entire surface of the wafer W was 0.3 ml, whereas in this embodiment, the entire surface of the wafer W was covered. The required amount of resist solution R was 0.2 ml. Therefore, according to the coating treatment method of the present embodiment, it was confirmed that the resist solution R can be uniformly coated on the entire surface of the wafer W with a small amount of liquid compared to the conventional method.

  As described above, according to the present embodiment, in the supplying step, before the diffusing resist solution reaches the outer periphery, the supply position for supplying the resist solution starts to move from the approximate center of the surface of the wafer W to the outer peripheral side, Thereafter, the supply position is moved to the outer peripheral side with the movement of the diffusing resist solution. As a result, the amount of resist solution per unit area at the tip of the diffusing resist solution can be increased, so that even when a smaller amount of resist solution is applied, the resist solution is diffused to the outer periphery of the wafer. be able to. Therefore, when the resist solution is applied to the entire surface of the wafer, the amount of the resist solution necessary to coat the entire surface of the wafer with the resist solution can be reduced.

In this embodiment, in the supplying step, the resist solution is supplied to the wafer surface while moving the resist solution nozzle so that the supply position is on the surface of the wafer and is included in the region where the resist solution is applied. The example to do was demonstrated. However, even if the supply position slightly exceeds the tip of the resist solution that diffuses, the same effect as in the present embodiment can be obtained. Therefore, if the supply position is moved to the outer peripheral side in accordance with the movement of the diffusing resist solution, in the supply process, the supply position is not included in the region where the resist solution is applied on the surface of the wafer. An example of moving the resist solution nozzle is also included.
(Modification of the embodiment)
Next, with reference to FIG.13 and FIG.14, the coating processing method which concerns on the modification of embodiment is demonstrated.

  FIG. 13 is a flowchart showing main steps of the resist coating process according to this modification. FIG. 14 is a graph showing the number of wafer rotations in each step of the resist coating process according to this modification.

  In the resist coating process according to this modification, in the supply step, the resist solution is supplied to the surface of the wafer while reducing the number of rotations of the wafer as the resist solution nozzle moves. This is different from the resist coating process.

  In this modification as well, the resist coating process corresponds to the coating method in the present invention. Also in this modification, the coating and developing treatment system 1 and the resist coating apparatus 30 described in the embodiment can be used.

  As shown in FIGS. 13 and 14, the resist coating process in this modification includes a solvent nozzle moving step (step S31), a solvent supplying step (step S32), a resist solution nozzle moving step (step S33), and a solvent diffusion step. (Step S34), a supply process (Steps S35 to S37), a first rotation process (Step S38), a second rotation process (Step S39), and a rotation stop process (Step S40). The supply process includes a center supply process (step S35), a movement start process (step S36), and a movement supply process (step S37).

  In addition, each process from the solvent nozzle movement process (step S31) to the movement start process (step S36) shown in FIG. 13 is started from the solvent nozzle movement process (step S11) described with reference to FIG. 6 in the embodiment. It is the same as each process of a process (step S16). Each process from the first rotation process (step S38) to the rotation stop process (step S40) shown in FIG. 13 is the same as the first rotation process (step S18) described in the embodiment with reference to FIG. It is the same as each process of a rotation stop process (step S20). Therefore, description of these steps is omitted.

  On the other hand, the movement supply process (step S37) shown in FIG. 13 is different from the movement supply process (step S17) described with reference to FIG. 6 in the embodiment.

  In the movement supply step (step S37), the resist solution nozzle 143 is moved from the center PC of the wafer W to the outer peripheral side in accordance with the movement of the resist solution R diffusing to the outer peripheral side, and the number of rotations at which the wafer W rotates is The resist solution R is supplied to the surface of the wafer W while being lowered as the resist solution nozzle 143 moves.

  The wafer W held on the spin chuck 130 is rotated at a predetermined rotational speed VS2-1 by the chuck driving mechanism 131, and the resist driving nozzle 143 is moved from the center PC of the wafer W to the outer peripheral side by the nozzle driving unit 144. It is moved to a predetermined position P for a predetermined time TS2. Then, as the resist solution nozzle 143 moves, the resist solution R is applied from the resist solution nozzle 143 to the surface of the wafer W while reducing the predetermined rotational speed from VS2-1 to VS2-2 as shown in FIG. Supply.

  Here, as an example, as shown in FIG. 14, the predetermined rotational speed VS2-1 can be set to 2000 rpm, for example, and the predetermined rotational speed VS2-2 can be set to 1800 rpm, for example. Further, the predetermined time TS2 can be set to 0.4 seconds, for example, and the predetermined position P can be set to 50 mm. That is, the resist solution nozzle 143 is moved 50 mm from the center PC in 0.4 seconds, and the rotation speed of the wafer W is decreased from 2000 rpm to 1800 rpm in 0.4 seconds.

  The predetermined rotational speed VS2-1 may be higher than the predetermined rotational speed VS1 in the center supply step (step S35), or may be lower than the predetermined rotational speed VS1.

  Further, the supply position PS at which the resist solution R is supplied from the resist solution nozzle 143 to the surface of the wafer W is included in the area AR on the surface of the wafer W where the resist solution R is applied. Further, the movement is the same as in the embodiment. In addition, the resist solution nozzle 143 may be moved so that the supply position PS is not included in the area AR as long as the supply position PS slightly exceeds the tip (outer periphery) FL of the resist solution R that diffuses. This is the same as in the embodiment.

  As described with reference to FIG. 12B in the embodiment, the resist solution R supplied to the center PC on the surface of the wafer W diffuses to the outer peripheral side of the wafer W by centrifugal force. As the diffusing resist solution R moves, the amount of the resist solution R per unit area at the tip (outer periphery) FL of the diffusing resist solution R decreases.

  Further, the passing speed at which the rotating wafer W passes below the resist solution nozzle 143 increases toward the outer peripheral side of the wafer W. When the passing speed increases, the resist solution R discharged from the resist solution nozzle 143 is repelled on the surface of the wafer W, and the amount of the resist solution R per unit area at the tip (outer periphery) FL may further decrease. .

  Also in this modification, since the resist solution nozzle 143 is moved in accordance with the movement of the resist solution R, the unit area at the tip (outer periphery) FL is the same as described with reference to FIG. The amount of the resist solution R can be increased. Thereby, even when a smaller amount of the resist solution R is applied, the resist solution R can be diffused to the outer periphery of the wafer W.

  Further, in the present modification, the rotational speed of the wafer W is decreased with the movement of the moving resist solution nozzle 143. Thereby, the passing speed at which the rotating wafer W passes under the resist solution nozzle 143 on the outer peripheral side of the wafer W can be reduced. Therefore, the resist solution R discharged from the resist solution nozzle 143 can be prevented from being repelled on the surface of the wafer W, and the amount of the resist solution R per unit area at the tip (outer periphery) FL can be increased. Therefore, the amount of liquid that can cover the entire surface of the wafer W with the resist liquid R can be further reduced.

  Further, in this modification, the predetermined rotation speed VS2 may not be decreased from VS2-1 to VS2-2 at a uniform change rate. For example, as shown in FIG. 14, the predetermined rotational speed VS2 may be decreased from VS2-1 to VS2-2 so that the absolute value of the change rate gradually decreases. Thereby, disorder of the spread of the resist solution R can be suppressed. Alternatively, the predetermined rotational speed VS2 may be decreased from VS2-1 to VS2-2 so that the absolute value of the change rate gradually increases.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. Can be modified or changed.

  In the embodiment and the modification of the embodiment, examples of the coating processing method and the coating processing apparatus for coating the resist solution have been described. However, in the coating treatment method and the coating treatment apparatus according to the present invention, the coating solution is not limited to the resist solution. Therefore, the present invention can also be applied to a coating processing method and a coating processing apparatus for coating various kinds of coating liquids such as a solvent and a chemical solution for forming an antireflection film.

  In addition, the present invention can be applied to a method including a step of applying a coating solution to a semiconductor substrate, a glass substrate, and other various substrates, and an apparatus for performing these steps.

130 Spin chuck 131 Chuck drive mechanism 143 Resist liquid nozzle 144 Nozzle drive unit 160 Control unit

Claims (11)

In the coating treatment method of applying the coating liquid to the surface of the substrate by supplying the coating liquid to the surface of the rotating substrate and diffusing the supplied coating liquid to the outer peripheral side of the substrate,
The coating liquid is supplied to the surface of the substrate while the supply position for supplying the coating liquid to the surface of the rotating substrate is moved to the outer peripheral side as the coating liquid diffuses to the outer peripheral side. have a supply process,
The supplying step supplies the coating liquid to substantially the center of the surface of the rotating substrate, diffuses the supplied coating liquid to the outer peripheral side, and before the diffusing coating liquid reaches the outer periphery of the substrate In addition, while maintaining the rotational speed of the rotating substrate so as to be included in the surface of the substrate where the coating liquid is applied, a predetermined distance from the approximate center of the surface of the substrate toward the outer peripheral side is determined. Moving the supply position to the position of
A coating treatment method characterized by that . The coating processing method according to claim 1, wherein the predetermined position is a position separated by 50 mm from the substantially central position . The coating method according to claim 1, wherein the rotation speed is approximately 2000 rpm . A first rotation step of rotating the substrate at a first rotation number lower than the rotation number of the substrate when the supply step is completed after the supply step;
After the first rotation step, the substrate, and a second rotating step of rotating at a second rotational speed higher than the first speed to one of claims 1 to 3 The coating process method of description. The first rotational speed is approximately 100 rpm,
The second rotational speed is approximately 1700 rpm.
The coating treatment method according to claim 4, wherein:   A computer-readable recording medium recording a program for causing a computer to execute the coating method according to any one of claims 1 to 5. In the coating treatment apparatus for applying the coating liquid to the surface of the substrate by supplying the coating liquid to the surface of the rotating substrate and diffusing the supplied coating liquid to the outer peripheral side of the substrate,
A substrate holder for holding the substrate;
A rotating unit for rotating the substrate holding unit holding the substrate;
A supply unit for supplying the coating liquid to the surface of the substrate held by the substrate holding unit rotated by the rotating unit;
A moving unit for moving the supply unit;
The mobile unit, have a control unit for controlling the operation of the supply unit and the rotating unit,
The control unit supplies the coating liquid to the approximate center of the surface of the substrate using the supply unit, diffuses the coating liquid to the outer peripheral side using the rotating unit, and uses the moving unit, Before the diffusing coating solution reaches the outer periphery of the substrate, the rotation speed of the rotating substrate is maintained so as to be included in the surface of the substrate where the coating solution is applied. Moving the supply position from the approximate center of the surface of the substrate toward the outer periphery to a predetermined position;
The coating processing apparatus characterized by the above-mentioned. The coating processing apparatus according to claim 7, wherein the predetermined position is a position separated by 50 mm from the substantially central position . The coating processing apparatus according to claim 7, wherein the rotation speed is approximately 2000 rpm . The control unit uses the rotating unit to rotate the coating liquid at a first rotation number lower than the rotation number after finishing the supply of the coating solution , and then rotates the second higher than the first rotation number. rotation causes in the number of rotations,
The coating processing apparatus according to claim 7, wherein the coating processing apparatus is characterized in that : The first rotational speed is approximately 100 rpm,
The second rotational speed is approximately 1700 rpm.
Wherein the coating apparatus according to claim 10.

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