JP2019102729A - Coating film forming method and coating film forming apparatus - Google Patents

Abstract

To form a coating film so as to have high uniformity of film thickness in each portion within a plane of the substrate including the inside of a recess when a coating film is formed by supplying a coating solution to the substrate having a concavo-convex pattern formed on the surface.SOLUTION: A coating film forming method includes: a step of holding a substrate W having a concavo-convex pattern formed in the surface, on a substrate holding portion 21; a discharge step of discharging mist of a coating liquid onto the surface of the substrate W held by the substrate holding portion 21; a coating step of rotating the substrate W in an inclined state or changing the inclination angle of the substrate in order to cause a coating liquid to flow in the concave portion forming the concavo-convex pattern and coat the side wall of the concave portion with the coating liquid; and a step of drying the coating liquid to form a coating film.SELECTED DRAWING: Figure 2

Description

  The present invention relates to the technical field of supplying a coating liquid to a substrate to form a coating film.

  In photolithography in a semiconductor manufacturing process, various coating liquids such as a resist are supplied to the surface of a semiconductor wafer (hereinafter, referred to as a wafer) which is a substrate to form a coating film. When the coating solution is applied, line and space, contact holes, etc. may be formed as a concavo-convex pattern on the surface of the wafer.

There is a demand for forming a coating film so as to have a film thickness with high uniformity at each part of the surface of the wafer including the inside of the concave portion without filling the concave portion of this pattern. That is, it may be required to form a coating film having high uniformity of film thickness at each part of the wafer so as to cover the side wall and the bottom in the recess. However, since the coating solution supplied into the recess moves to the bottom of the recess by gravity, the film thickness of the bottom increases, but the side wall of the recess is difficult to be covered by the coating film. Although Patent Document 1 discloses that film formation is performed by supplying a mist-like coating liquid from a nozzle to a substrate having irregularities on the surface, it is insufficient to solve the above problems.

JP, 2005-19560, A

The present invention has been made to solve such a problem, and the problem is that the substrate including the inside of the recess is formed when the coating liquid is supplied to the substrate having the concavo-convex pattern formed on the surface to form the coating film. The coating film is formed so as to increase the uniformity of the film thickness at each in-plane portion.

The method for forming a coated film according to the present invention comprises the steps of:
A discharge step of discharging a mist of a coating liquid onto the surface of the substrate held by the substrate holding portion;
In order to cause the coating solution to flow in the recess forming the concavo-convex pattern and coat the side wall of the recess with the coating solution, the substrate is rotated in an inclined state or a coating for changing the inclination angle of the substrate Process,
Drying the coating solution to form a coating film;
And the like.

  According to the present invention, the coating solution is made to flow by rotating the substrate supplied with the coating solution mist in an inclined state or changing the tilt angle. Thus, the side wall of the concave portion forming the concavo-convex pattern can be coated with the coating liquid, and the coating film can be formed so as to increase the uniformity of the film thickness in each in-plane portion of the substrate including the inside of the concave portion.

It is a top view of a substrate processing device containing a resist film formation module concerning the present invention. It is a vertical side view of the said resist film formation module. It is a top view of the said resist film formation module. It is explanatory drawing of the change operation of the inclination in the said resist film formation module. It is a perspective view of the wafer processed by the said resist film formation module. It is a perspective view of the said wafer. It is a perspective view of the said wafer. It is a perspective view of the said wafer. It is a perspective view of the said wafer. It is a perspective view of the said wafer. It is a vertical side view which shows the surface of the said wafer. It is a vertical side view which shows the surface of the said wafer. It is a vertical side view which shows the surface of the said wafer. It is a vertical side view which shows the surface of the said wafer. It is a vertical side view which shows the surface of the said wafer. It is a vertical side view which shows the surface of the said wafer. It is a perspective view of the said wafer. It is a perspective view of the said wafer. It is a vertical side view which shows the surface of the said wafer. It is a vertical side view which shows the surface of the said wafer. It is a vertical side view of another resist film formation module concerning the present invention. It is a top view of the said resist film formation module. It is a perspective view of the wafer processed by the said resist film formation module. It is a vertical side view of another resist film formation module concerning the present invention. It is a perspective view of the conveyance mechanism provided in the substrate processing apparatus. It is a perspective view of the said conveyance mechanism. It is a perspective view for demonstrating a mode that the inclination of a wafer changes. It is a top view for demonstrating a mode that the inclination of a wafer changes.

  A substrate processing apparatus 1 including a resist film forming module according to an embodiment of a coated film forming apparatus of the present invention will be described with reference to the plan view of FIG. The substrate processing apparatus 1 includes a carrier block D1 and a processing block D2. The carrier block D1 includes a mounting table 12 for mounting a carrier 11 for storing a wafer W, which is a circular substrate, and a transport mechanism 13 for delivering the wafer W between the carrier 11 and the processing block D2. There is. An uneven pattern is formed on the surface of the wafer W as described in the background art section.

The main transport mechanism 14 is provided in the processing block D2. Further, units U1 to U3 and a resist film forming module 2 are provided so as to surround the main transport mechanism 14 in plan view. The units U1 to U3 are stacks of modules. For example, the unit U1 includes a delivery module 15, and the units U2 and U3 each include a heating module 16. The transfer mechanism 13 described above delivers the wafer W to the delivery module 15. The resist film forming module 2 supplies a resist, which is a coating liquid, to the surface of the wafer W to form a resist film, which is a coating film. The resist film forming module 2 will be described in detail later.

The heating module 16 heats the wafer W on which the resist film is formed by the resist film forming module 2 to volatilize and remove the solvent contained in the resist film. The main transport mechanism 14 horizontally supports the back surface of the wafer W and transports the wafer W between the modules of the processing block D2. In the substrate processing apparatus 1, the wafer W is transported and processed in the following order: carrier 11 → delivery module 15 → resist film forming module 2 → heating module 16 → delivery module 15 → carrier 11.

The resist film forming module 2 is configured such that the concave portion for forming the concavo-convex pattern on the wafer W is not filled up with the resist, and along the surface of the concavo-convex pattern, a resist film with high film thickness can be formed at each part of the surface. It is done. The resist film forming module 2 will be described with reference to the longitudinal side view of FIG. 2 and the plan view of FIG. In the figure, reference numeral 21 denotes a horizontal circular spin chuck which is a substrate holding unit. The spin chuck 21 has a mounting surface 20 for mounting the central portion of the back surface of the wafer W, and the mounted wafer W is held by suction by the mounting surface 20 and held horizontally. In the figure, reference numeral 22 denotes a rotation mechanism, which is connected to the spin chuck 21 via a vertical shaft portion 23, and the spin chuck 21 is rotated about the central axis by the rotation mechanism 22. Since the wafer W is mounted on the spin chuck 21 so that the center thereof is aligned with the center of the spin chuck 21 in plan view, the wafer W also rotates around its central axis.

  In the figure, reference numeral 31 denotes a cup, which is provided so as to surround the wafer W held by the spin chuck 21 in order to receive waste liquid scattered or spilled from the rotating wafer W. In the figure, reference numeral 30 denotes an opening formed in the cup 31 for carrying the wafer W in and out, and is open in the vertical direction. In the figure, 32 is a drainage port opened at the bottom of the cup 31. In the drawing, reference numeral 33 denotes an exhaust pipe provided upright at the bottom of the cup, and exhausts the inside of the cup 31 during processing of the wafer W in the resist film forming module 2. In addition, in the cup 31, although the guide member which guides the drainage to the drainage port 32 and the exhaust pipe 33 and exhaust_gas | exhaustion is provided, illustration is abbreviate | omitted.

In the drawing, reference numeral 34 denotes a horizontal support plate surrounding the shaft 23, and three vertical lift pins 35 (only two are shown in FIG. 1) are spaced along the rotational direction of the wafer W. It is supported by the support plate 34. The support plate 34 is configured to be able to move up and down by a lifting mechanism 36 provided in the cup 31. That is, the lift pins 35 are lifted and lowered by the lift mechanism 36 to deliver the wafer W between the main transport mechanism 14 and the spin chuck 21 described above.

The rotation mechanism 22 described above is connected to the inclination change mechanism 37. Further, the inclination changing mechanism 37 is connected to the bottom of the cup 31 via, for example, a connection arm 38. The tilt changing mechanism 37 rotates the cup 31, the spin chuck 21, the shaft portion 23 and the rotating mechanism 22 around the horizontal axis R so as to maintain the positional relationship between these members. It can be changed. Therefore, the inclination of the wafer W held by the spin chuck 21 can be changed.

This will be described with reference to FIG. An axis passing the central axis of the wafer W, ie, the center of the wafer W, and orthogonal to the surface of the wafer W is R1. The vertical axis is R2, and the angle between the central axis R1 and the vertical axis R2 is the inclination angle θ. In the processing in this embodiment, when supplying the resist to the wafer W, the inclination angle θ = 0 °, that is, the surface of the wafer W is horizontal. Then, after the resist is supplied to the wafer W, the inclination angle θ = 90 °, that is, the surface of the wafer W is made vertical. As described above, the respective parts of the wafer W and the resist film forming module 2 when θ = 0 ° are indicated by broken lines in FIG. 4, and the respective parts of the wafer W and the resist film forming module 2 when θ = 90 ° are indicated by Each is shown by a solid line in FIG.

  Returning to FIGS. 2 and 3, the description will be continued. In the figure, reference numeral 41 denotes a resist supply nozzle for forming a spray, and has a discharge hole 42 opened downward. In the figure, reference numeral 43 denotes a resist supply source, which supplies a resist to the resist supply nozzle 41. In the figure, reference numeral 44 denotes a supply source of N 2 (nitrogen) gas, which supplies the resist supply nozzle 41 with N 2 gas. The supply of the resist to the resist supply nozzle 41 and the supply of the N 2 gas are simultaneously performed, and the resist supplied to the resist supply nozzle 41 is misted by the action of the N 2 gas and is downward from the discharge hole 42 together with the N 2 gas. It is sprayed.

As described above, the resist is not in a liquid flow state, but is atomized and supplied to the wafer W in order to prevent the concave portion formed on the surface of the wafer W from being completely filled in the resist. Further, the resist supply source 43 has a relatively low viscosity for the purpose of discharging the resist from the resist supply nozzle 41 in such a mist state and causing the resist to flow on the surface of the wafer W as described later. For example, resists of 3 cP to 10 cP are supplied to the resist supply nozzle 41.

In FIG. 3, 45 is an arm supporting the resist supply nozzle 41 at its tip end side, and the base end side of the arm 45 is connected to the moving mechanism 46. The moving mechanism 46 raises and lowers the arm 45 and is horizontally movable along the guide rail 47. By the movement along the guide rail 47, the discharge holes 42 of the resist supply nozzle 41 can move on the diameter of the rotating wafer W, and the mist of the resist can be supplied to the entire surface of the wafer W.

In the figure, 51 is a thinner supply nozzle. In the figure, 52 is a thinner supply source, and supplies thinner to the thinner supply nozzle 51. The thinner supply nozzle 51 discharges the thinner as a liquid flow downward. The thinner is a processing solution for performing pre-wetting in which the surface of the wafer W is wetted and reformed before the supply of the resist, and promotes the penetration of the resist into the recess. In the figure, 53 is an arm which supports the thinner supply nozzle 51 at its distal end side, and the proximal end side of the arm 53 is connected to the moving mechanism 54. The moving mechanism 54 raises and lowers the arm 53 and is horizontally movable along the guide rail 47. The thinner supply nozzle 51 can supply thinner on the central portion of the wafer W, and the thinner is supplied to the entire surface of the wafer W by spin coating by rotation of the wafer W.

  As shown in FIG. 2, the resist film forming module 2 is provided with a control unit 10 which is a computer. A program stored in a storage medium such as, for example, a compact disk, a hard disk, an MO (magneto-optical disk), a memory card, and a DVD is installed in the control unit 10. The installed program transmits a control signal to each part of the resist film forming module 2 to control its operation, and has instructions (each step) incorporated so that processing described later can be performed. Specifically, change of the rotation speed of the wafer W by the rotation mechanism 22, elevation of the elevation pin 35 by the elevation mechanism 36, inclination of the cup 31 and the spin chuck 21 by the inclination change mechanism 37, resist supply nozzle 41 from the resist supply source 43 Supply of resist, supply of N 2 gas from the N 2 gas supply source 44 to the resist supply nozzle 41, supply of thinner from the thinner supply source 52 to the thinner supply nozzle 51, movement of the resist supply nozzle 41 by the movement mechanism 46, movement The operation such as the movement of the thinner supply nozzle 51 by the mechanism 54 is controlled by the program.

  Subsequently, processing of the wafer W in the resist film forming module 2 will be described with reference to FIGS. 5 to 10 and 11 to 15. 5 to 10 are perspective views of the wafer W processed in the resist film forming module 2, and FIGS. 11 to 15 show how the longitudinal side view of the wafer W changes. FIG. 11 shows the wafer W when being transferred to the resist film forming module 2. In the figure, reference numeral 61 denotes a concave portion having a concavo-convex pattern. The width L1 of the recess 61 is, for example, 10 μm to 50 μm, and more specifically, 25 μm. The height H1 of the recess 61 is 50 μm to 200 μm, more specifically, for example, 100 μm. The aspect ratio = H1 / L1 is, for example, 2 to 10.

With the opening 30 of the cup 31 facing upward and the mounting surface 20 of the spin chuck 21 being horizontal, the wafer W on which the concavo-convex pattern described in FIG. It is transported. The center of the back surface of the wafer W is mounted on the mounting surface 20 and adsorbed by the elevating operation of the elevating pins 35, and the inclination angle θ described in FIG. 4 becomes 0 ° so that the surface becomes horizontal. Thus, the wafer W is held by the spin chuck 21 (FIG. 5).

After that, the thinner supply nozzle 51 is located on the center of the wafer W. Then, while the thinner 62 is supplied to the central portion of the wafer W, the wafer W rotates and centrifugal force spreads the thinner 62 at the peripheral portion of the wafer W, thereby performing pre-wetting (FIG. 6). Thereafter, the supply of the thinner 62 is stopped, and the thinner supply nozzle 51 retracts from above the wafer W to the outside of the cup 31. Subsequently, the resist supply nozzle 41 is positioned above the wafer W, and the wafer W rotates at, for example, 600 rpm or less. Then, the resist supply nozzle 41 discharges the mist of the resist 63 while reciprocating between the central portion and the peripheral portion of the wafer W, and the resist 63 is supplied over the entire surface of the rotating wafer W (see FIG. Figure 7). Therefore, a liquid film of the resist 63 is formed on the outside of the concave portion 61, that is, on the convex portion. In addition, because the flowability of the resist 63 on the surface of the wafer W is high because pre-wetting is performed, a relatively large amount of the resist 63 enters the recess 61 and is stored at the bottom of the recess 61 by gravity. Be done (Figure 12).

Thereafter, the discharge of the mist of the resist 63 is stopped from the resist supply nozzle 41, and the resist supply nozzle 41 retracts from above the wafer W, and, for example, the rotation of the wafer W is temporarily stopped. Subsequently, the spin chuck 21 and the cup 31 are inclined by the inclination changing mechanism 37, and the surface of the wafer W becomes vertical. That is, as described in FIG. 4, the inclination angle θ = 90 °. As the wafer W is thus inclined, the resist 63 still having fluidity flows to the side wall of the recess 61 in the middle of drying in the recess 61, and the side wall and the bottom of the recess 61 form the resist 63. It will be in the covered state (FIG. 13). Then, the wafer W is rotated at, for example, 600 rpm or less with the θ = 90 ° state, and the resist 63 flows in the circumferential direction of the recess 61 along the sidewall of the recess 61 by this rotation, and the entire sidewall of the recess 61 is resist 63 is coated. That is, the entire inside of the recess 61 and the outside of the recess 61 are covered with the resist 63 (FIG. 14).

Then, due to the air flow around the wafer W due to the rotation, the drying of the resist 63 proceeds, and a resist film 64 is formed along the unevenness of the surface of the wafer W in the entire surface of the wafer W (FIG. 15). The film thickness L3 of the resist film 64 is, for example, 500 nm to 10 μm. Thereafter, the rotation of the wafer W is stopped, and the tilt of the spin chuck 21 and the cup 31 is changed such that the tilt angle θ returns to 0 °. That is, the wafer W is horizontal (FIG. 10). Thereafter, the wafer W is delivered from the spin chuck 21 to the main transport mechanism 14 by the elevation of the lift pins 35.

In the resist film forming module 2, the mist of the resist 63 is sprayed onto the entire surface of the wafer W with the wafer W in a horizontal state, and then the wafer W is inclined and supplied to the recess 61 by rotating. By flowing the resist 63 in the recess 61 and covering the side wall with the resist 63, the resist film 64 along the concavo-convex pattern is uniformly filled on the entire surface of the wafer W without filling the recess of the pattern. It can be formed with high film thickness.

  By the way, in the processing described above, the number of rotations of the wafer W when supplying the resist mist and the number of rotations of the wafer W when tilting and rotating the wafer W to cover the side wall in the recess 61 In order to complete quickly, it is preferable to set each to a large value. However, as described above, since the viscosity of the resist 63 is relatively low, the resist 63 is scattered from the wafer W when the number of rotations is too large. From such a point of view, it is preferable to set the rotation speed to 600 rpm or less as described above.

Further, in the above process, the resist coating nozzle 41 is reciprocated between the center portion and the peripheral end portion of the wafer W, but one of the central portion and the peripheral end portion is not reciprocated as such. The resist 63 may be supplied by a single movement from one to the other. In addition, if the resist 63 can be supplied to the entire surface of the wafer W by using a relatively large nozzle or a plurality of nozzles, the resist coating nozzle 41 does not have to move, The wafer W may not rotate at the time of the supply of 63.

Further, the present invention is not limited to rotating the wafer W horizontally when supplying the mist of the resist 63. For example, the wafer W is rotated at an inclination angle θ of 5 to 30 °, and then the side wall is coated with the resist 63. May be rotated to a larger value, for example, 90.degree. As described above. However, it is preferable to supply the resist 63 to the wafer W in the horizontal state in order to supply the resist 63 with a high uniformity to the surface of the wafer W to make the film thickness of the resist film 64 uniform. It should be noted that the case of having a slight inclination with respect to the horizontal plane, for example, an inclination within 3 °, is also included in being horizontal due to an assembly error of the parts of the device, processing accuracy, and the like.

In the substrate processing apparatus 1 described above, the transfer of the wafer W may be repeated plural times in the order of the resist film forming module 2 and the heating module 16 so that a plurality of resist films 64 may be stacked. FIG. 16 shows an example in which the two-layered resist film 64 is stacked by repeating the transportation in the above order twice. The resist film can be formed so as to have a desired film thickness by performing conveyance in this manner and repeating the formation of the resist film and the removal of the solvent from the resist film by heating.

By the way, in the above example, the wafer W is inclined such that the inclination angle θ is 90 ° in order to cover the side wall of the recess 61 with the resist 63. Is not limited. However, if the inclination angle θ is too small, the side wall in the recess 61 is not covered with the resist 63. Therefore, the inclination angle θ is set to 20 ° or more. And in this specification, when inclination angle theta is 20 degrees or more like that, wafer W shall be in the state where it was inclined. The inclined state means that it is inclined with respect to the horizontal plane.

Although the resist 63 is described as covering the side wall with the resist 63 by supplying the resist 63 accumulated on the bottom of the recess 61 to the side wall of the recess 61 when the inclination angle θ is 90 °, the inclination angle θ is When the wafer W is tilted such that the angle of inclination is smaller than 90.degree., The resist 63 accumulated on the opening edge of the recess 61 is transmitted along the side wall toward the bottom of the recess 61, as in the case where the inclination angle .theta. The side wall of the recess 61 can be coated with the resist 63 by rotating the wafer W in the inclined state. However, in order to prevent the film thickness of the resist film 64 at the bottom of the recess 61 from becoming large, it is preferable that the resist 63 accumulated at the bottom of the recess 61 be supplied to the side wall of the recess 61. The angle θ is particularly preferably 70 ° or more.

The cup 31 is not limited to being inclined together with the wafer W as long as the scattering of the coating liquid from the wafer W during the coating process can be suppressed. Specifically, for example, the spin chuck 21, the shaft portion 23, the rotation mechanism 22 and the inclination changing mechanism 37 are provided in the cup 31, and the inclination changing mechanism 37 does not change the inclination of the cup 31. The tilt of the wafer W may be changed.

Further, the pre-wet thinner may be applied to the wafer W by the same method as the resist. Specifically, similar to the resist discharge nozzle 41, the thinner discharge nozzle 51 is configured to mist the thin film and supply it to the wafer W. Then, for example, the thinner discharge nozzle 51 is operated in the same manner as the resist discharge nozzle 41 described with reference to FIG. That is, for the wafer W rotating in the horizontal state, mist of thinner is discharged from the thinner discharge nozzle 51 moving above the wafer W. Thereafter, as described in FIGS. 8 and 9, the wafer W is rotated with the inclination angle θ = 90 ° to perform pre-wet so as to spread the thinner in the recess 61. After the pre-wetting, the wafer W is returned horizontally, and the resist 63 is applied as described in FIGS. 7 to 9 to form a resist film.

As described above, the step of discharging the mist of the thinner onto the surface of the wafer W, and the flow of the thinner in the recess formed on the surface of the wafer W to incline the wafer W in order to supply the thinner to the side wall of the recess By performing pre-wetting so as to include the step of rotating in the above state, thinner can be uniformly supplied to each portion of the surface of the wafer W including the side wall in the recess 61. By supplying the thinner in this way, the uniformity of each part in the surface of the wafer W can be made higher with respect to the film thickness of the resist film 64 formed after pre-wet, and the wafer W surface by the resist film 64 Can be made higher. The pre-wet method can also be applied to the method described as that for forming a resist film after that. Therefore, the thinner may be distributed in the recess 61 by performing the process of changing the inclination angle of the wafer W after supplying the thinner to the wafer W.

Another processing example in the resist film forming module 2 will be described with reference to the perspective view of the wafer W in FIGS. 17 and 18 and the longitudinal side view of the wafer W in FIGS. First, after performing pre-wet as described in FIGS. 6 and 7, the mist of the resist 63 is supplied to the surface of the wafer W, and then the surface of the wafer W moves downward and becomes horizontal by the inclination changing mechanism 37 As such, the wafer W is tilted. That is, the wafer W is tilted so that the above-mentioned angle θ = 180 ° (FIG. 17).

The resist 63 accumulated at the bottom of the recess 61 is moved downward by the action of gravity. At that time, due to the action of surface tension, the resist 63 flows along the side wall of the recess 61 and flows to the opening edge of the recess 61 and joins with the liquid film of the resist 63 adhering to the outside of the recess 61 by surface tension (see FIG. 19). Then, the wafer W rotates (FIG. 18), and the resist 63 attached to the side wall of the recess 61 moves along the side wall by the action of the centrifugal force. Even if there is a portion where the resist 63 is not supplied among the side walls, the resist 63 is supplied to the corresponding portion by the movement of the resist 63, and the entire side wall is covered with the resist 63. Then, the wafer W is exposed to the air flow by the rotation of the wafer W to accelerate the drying of the resist 63, and the resist film 64 is formed (FIG. 20). As described above, the inclination angle θ at the time of covering the side wall of the recess 61 can be set to a value of 180 ° or less.

Subsequently, a resist film forming module 7 which is a modified example of the resist film forming module 2 will be described with reference to the longitudinal sectional view of FIG. 21 and the plan view of FIG. Do. In the resist film forming module 7, an elevating mechanism 71 is provided at a distal end portion of an arm 45 whose proximal end is connected to the moving mechanism 46 described above. The lift arm 72 provided at the tip of the arm 45 is lifted and lowered by the lift mechanism 71, and the resist supply nozzle 41 described above is provided on the lift arm 72. In the resist supply nozzle 41, the discharge holes 42 are opened laterally toward the surface of the wafer W having the above-mentioned inclination angle θ = 90 °, that is, the surface of the vertical wafer W. Then, the discharge holes 42 move along the diameter of the wafer W as viewed from the front side of the rotating wafer W by the elevation of the elevation arm 72.

In this resist film forming module 7, as described in FIG. 6 as in the case of the resist film forming module 2, after prewetting is performed at the inclination angle θ = 0 °, the inclination angle θ = 90 °, and the wafer W is Rotate. Then, the resist supply nozzle 41 is repeatedly moved up and down so that the discharge hole 42 reciprocates between the position toward the center of the wafer W and the position toward the peripheral end of the wafer W. The mist of the resist 63 is discharged from (FIG. 23). Since the resist 63 is discharged toward the bottom and the protrusion of the recess 61 of the wafer W, the resist 63 is supplied to the bottom and the protrusion of the recess 61. Then, a part of the resist 63 supplied to the bottom of the recess 61 is supplied to the side wall of the recess 61 by gravity. Therefore, the resist 63 flows in the recess 61 as in the example shown in FIG.

Since the wafer W is rotating, the resist 63 thus supplied to the side wall of the recess 61 flows in the circumferential direction of the recess 61 along the side wall, and as shown in FIG. The resist 63 is coated with the surface of the wafer W including the bottom and the entire sidewall. Thereafter, the discharge of the resist 63 from the resist supply nozzle 41 is stopped, the resist 63 on the surface of the wafer W is dried, and a resist film 64 is formed as shown in FIG.

FIG. 24 shows a resist film forming module 74 which is a further modification of the resist film forming module 2, and such a resist film forming module 74 is provided in the substrate processing apparatus 1 instead of the resist film forming module 2. It is also good. The resist film forming module 74 is not provided with the inclination changing mechanism 37, and the cup 31, the spin chuck 21, the shaft portion 23 and the rotating mechanism 22 in the resist film forming module 74 have an inclination angle θ in the resist film forming module 2. It is configured to have the same inclination as the cup 31, the spin chuck 21, the shaft 23 and the rotation mechanism 22 in the state of 90 °. Accordingly, the opening 30 of the cup 31 opens in the lateral direction, and the mounting surface 20 of the spin chuck 21 is vertical.

The resist film forming module 74 is not provided with the elevation pins 35 and the elevation mechanism 36, and the rotation mechanism 22 is connected to the horizontal movement mechanism 75. The spin chuck 21 performs processing of the wafer W in the cup 31 by the horizontal movement mechanism 75 (indicated by a solid line in the figure) and the main transport mechanism 14 outside the cup 31 as described later. Thus, the wafer W can be moved between a delivery position (denoted by a dashed line in the figure) for delivering the wafer W. Note that the drainage port 32 of the cup 31 is provided below the opening 31 of the cup 31 so that the liquid can be drained from the inside of the cup 31.

In the resist film forming module 74, the resist supply nozzle 41 provided on the lift arm 72 is moved up and down by the lift mechanism 71 similarly to the resist film forming module 7, and the entire surface of the wafer W is raised similarly to the resist film forming module 7. Supply of the resist 63 is performed. Further, for example, the thinner supply source 52 is connected to the resist supply nozzle 41, and the thinner is also mixed with the N 2 gas by the resist supply nozzle 41 in the same manner as the resist and is discharged onto the wafer W in a mist state. Therefore, the pre-wetting in the resist film forming module 74 is performed by raising and lowering the resist supply nozzle 41 in the state of discharging the thinner during the rotation of the wafer W in the same manner as the supply of the resist described in FIG.

An example of the main transport mechanism 14 of the substrate processing apparatus 1 provided with the resist film forming module 74 is shown in FIG. In the figure, reference numeral 81 denotes a C-shaped main body in plan view surrounding the side periphery of the wafer W. In the figure, reference numeral 82 denotes a support portion for supporting the peripheral portion of the back surface of the wafer W, and a plurality of support portions are provided at intervals in the circumferential direction of the main body portion 81. The support portion 82 includes a mounting surface of the wafer W, which is a flat surface, and a suction hole 83 for sucking and holding the back surface of the wafer W is opened in the mounting surface. When the wafer W is held on the mounting surface, suction from the suction holes 83 is performed, and when each module receives the wafer W, suction from the suction holes 83 is stopped. In the figure, 84 is a rotation mechanism connected to the main body 81, and can rotate the main body 81 about a horizontal axis. The rotation mechanism 84 is configured to be movable back and forth and to be rotatable about a vertical axis.

When the wafer W is delivered to each module other than the resist film forming module 74 of the processing block D2, as shown in FIG. 25, the mounting surface of the support portion 82 is horizontal so that the wafer W can be held horizontally. Become. When the wafer W is delivered to the resist film forming module 74, the mounting surface of the support portion 82 is vertical so that the wafer W can be held vertically as shown in FIG. By moving the spin chuck 21 horizontally to the delivery position described above, the central portion of the back surface of the wafer W held vertically as such is attracted, and delivery of the wafer W is performed between the main body 81 and the spin chuck 21. It can be carried out. After the wafer W is delivered to the spin chuck 21, the spin chuck 21 moves to the processing position in the cup 31, prewet is performed as described above, and the resist 63 is supplied, and the resist film 64 is then supplied. Is formed.

In addition, by rotating the wafer W in the inclined state, the side wall of the recess 61 is not limited to being coated with the resist 63. The lower end of the shaft portion 23 is connected to the tilt direction changing mechanism 85 shown in FIGS. 27 and 28, and the upper end of the shaft portion 23 is connected to the holding portion 86 having the same configuration as the spin chuck 21 that holds the back surface of the wafer W by suction. It is done. However, in FIG. 27, the display of the holding unit 86 is omitted. The inclination changing mechanism 85 changes the inclination of the shaft portion 23 so as to draw a circle R3 along the horizontal surface. As described above, while the circle R3 is drawn, the tilt direction changing mechanism 85 changes the direction in which the shaft portion 23 tilts so that the position of the lower end on the periphery of the wafer W changes. That is, in the state where the wafer W is inclined, the inclination direction of the wafer W is changed. More specifically, the direction of the inclination of the central axis R1 of the wafer W with respect to the vertical axis R2 changes while the inclined state of the wafer W is maintained. More specifically, assuming that positions on the circumferential edge of the wafer W which are equally spaced from one another are P1 to P4, and positions on the circle R3 which are different from one another and equally spaced from one another are Q1 to Q4, the centers of the wafer W are When positioned at the positions Q1, Q2, Q3 and Q4, the tilt changing mechanism 85 changes the tilt of the shaft 23 so that the positions P1, P2, P3 and P4 at the peripheral end of the wafer W are at the lower end.

For example, when supplying pre-wet and resist mist as shown in FIGS. 6 and 7, the inclination changing mechanism 85 makes the shaft portion 23 vertical and performs processing with the wafer W in a horizontal state. Make it After that, the inclination direction of the wafer W is changed so that the center of the wafer W moves along the circle R3 as described above, the side wall of the recess 61 is covered with the resist 63, and the wafer W The resist 63 is dried by an air flow formed by moving to form a resist film 64. Thus, changing the direction of the tilt of the wafer W changes the tilt of the central axis of the wafer W with respect to the vertical axis when viewed from the side as shown in FIG. Shall be included in the change of the inclination angle of.

By the way, in the resist film forming module 2 described above, after the mist of the resist 63 is supplied as described in, for example, FIG. 7 in a state where the wafer W is horizontal, the wafer W is inclined by the inclination changing mechanism 37. That is, the tilt angle may be changed without rotating the wafer W. By changing the inclination angle, the resist 63 can be made to flow in the recess 63 so that the entire surface of the wafer W including the inside of the recess 63 is covered with the resist 63. Further, the mist of the resist 63 is supplied to the wafer W in the inclined state, and thereafter, the resist 63 is made to flow by changing the inclination angle of the wafer W, and the entire surface of the wafer W including the inside of the concave portion 61 becomes the resist 63. It may be coated.

The coating solution is not limited to the resist, but may be a chemical solution containing, for example, an antireflective film or an insulating film as the coating film. Further, the substrate is not limited to a wafer, and various substrates such as a flat panel display substrate, a substrate for a solar cell, and a printed substrate can be used. Further, the present invention is not limited to the above-described embodiments, and the respective embodiments can be combined with each other, and may be appropriately modified.

W wafer 1 substrate processing apparatus 10 control unit 2 resist film forming module 21 spin chuck 22 rotation mechanism 31 cup 37 inclination changing mechanism 41 resist supply nozzle

Claims (12)

Holding a substrate on the surface of which a concavo-convex pattern is formed on a substrate holder;
A discharge step of discharging a mist of a coating liquid onto the surface of the substrate held by the substrate holding portion;
In order to cause the coating solution to flow in the recess forming the concavo-convex pattern and coat the side wall of the recess with the coating solution, the substrate is rotated in an inclined state or a coating for changing the inclination angle of the substrate Process,
Drying the coating solution to form a coating film;
A method for forming a coated film, comprising: The method for forming a coated film according to claim 1, wherein the coating step is a step of rotating the substrate in an inclined state.   The method for forming a coated film according to claim 2, wherein the discharging step includes the step of discharging the mist onto the substrate rotating in an inclined state.   The method for forming a coated film according to claim 2, wherein the coating step includes the step of rotating the substrate in a state in which the inclination is larger than when the discharge step is performed. 5. The method for forming a coated film according to claim 4, wherein the discharging step is a step of discharging the mist onto the substrate in a horizontal state. The coating step is a step of changing the tilt angle of the substrate,
The method for forming a coated film according to claim 1, further comprising the step of changing the direction of inclination of the substrate. A substrate holding unit for holding a substrate having a concavo-convex pattern formed on its surface;
A coating solution discharge nozzle for discharging a mist of a coating solution for forming a coating film by drying on the surface of the substrate held by the substrate holding unit;
Change the tilt angle of the rotating mechanism or substrate that is provided to flow the coating solution in the recess that forms the concavo-convex pattern and coat the side wall of the recess with the coating solution, which rotates the substrate in an inclined state Tilt change mechanism,
An apparatus for forming a coated film, comprising: The coated film forming apparatus according to claim 7, wherein the rotation mechanism is provided.   9. The coating film forming apparatus according to claim 8, wherein the coating liquid discharge nozzle has a discharge hole opened laterally to supply the mist to the substrate which is rotated in a state of being inclined by the rotation mechanism. . The tilt change mechanism is configured to change the tilt angle of the rotatable substrate, and the tilt change mechanism;
A control unit that outputs a control signal to rotate the substrate in a state in which the inclination is larger than during the supply of the mist to the substrate after the mist is supplied to the substrate;
The coated film forming apparatus according to claim 8, comprising:   11. The coated film forming apparatus according to claim 10, wherein the substrate is in a horizontal state during the supply of the mist. The tilt changing mechanism is provided;
The apparatus for forming a coated film according to claim 7, wherein the tilt changing mechanism changes the direction of the tilt of the substrate.

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