TW201334874A - Coating process device, coating process method and computer storage medium - Google Patents

Abstract

The invention is a coating process device that applies a coating fluid onto a substrate by forming a pool of the coating fluid that has been discharged from a discharge opening of an application nozzle, said pool being formed between the substrate and the discharge opening, and in said state, moving the substrate and the application nozzle relative to each other in a horizontal direction. Said coating process device comprises: an application nozzle that communicates with the discharge opening, and is provided with a storage chamber that stores the coating fluid therein; a pressure adjustment mechanism that adjusts the pressure inside the storage chamber; and a control section configured to control the pressure adjustment mechanism, and while applying coating fluid to the substrate surface, to adjust the pressure within the storage chamber such that the discharge rate of the coating fluid from the discharge opening is constant.

Description

Coating processing device, coating processing method, program, and computer memory medium

The present invention relates to a coating processing apparatus, a coating processing method, a program, and a computer memory medium for applying a coating liquid to a substrate.

For example, in the photolithography step in the manufacturing process of the semiconductor device, for example, a resist coating liquid is applied on a semiconductor wafer (hereinafter referred to as "wafer") to form a resist film coating process, The resist film is exposed to a predetermined pattern of exposure treatment, the exposed resist film is developed for development, and the like, and a predetermined resist pattern is formed on the wafer.

The method for forming the above-mentioned resist film is to drop the resist from the nozzle to the center of the wafer in a state where the wafer is rotated, so that the resist liquid is diffused on the wafer by centrifugal force. The resist film is spread on the wafer, known as spin coating.

However, when the spin-coated resist film is formed, since the dropped resist is diffused by high-speed rotation, most of the dropped resist is scattered from the outer peripheral edge of the wafer to cause waste.

Therefore, for example, Patent Document 1 proposes a method of applying a liquid while forming a liquid accumulation between a nozzle and a wafer in order not to waste the resist liquid. Specifically, for example, as shown in FIG. 18, the slit-shaped discharge port 101 formed on the lower end surface of the nozzle portion 100 is brought close to the wafer W, and a predetermined gap is formed between the discharge port 101 and the wafer W. In this state, the tube 103 communicating with the reservoir portion 102 formed inside the mouth portion 100 is advanced. Line open operation. Thereby, the resist liquid 104 stored in the storage portion 102 is discharged by its own weight and capillary phenomenon, and a liquid film is formed between the wafer W and the discharge port 101.

Then, in a state where a liquid film is formed between the wafer W and the discharge port 101, the nozzle portion 100 is moved in the radial direction of the wafer W, for example. Thereby, the resist liquid 104 is discharged from the slit-shaped discharge port 101 by its own weight and capillary phenomenon, and as a result, the resist liquid 104 is applied to the wafer W without being wasted.

[Advanced technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 8-173875

According to the coating treatment method of the above Patent Document 1, for several tens of mPa. The coating solution with a lower viscosity around s is effective. However, for example, the viscosity is 100mPa. In the high-viscosity coating liquid such as the above-mentioned resist liquid or polyimine, since the flow path resistance of the discharge port 101 becomes large, it is difficult to apply the coating liquid by its own weight or capillary phenomenon.

In order to reduce the resistance of the flow path, for example, it is conceivable to enlarge the slit width of the discharge port 101. However, when the slit width is enlarged, the coating liquid cannot be held by the discharge port 101, and there is a problem that the film thickness is poor when the liquid droplets are dropped or applied.

Moreover, after being verified by the inventors, the coating by Patent Document 1 In the treatment method, the coating liquid has a different film thickness at the end portion of the substrate on the application start side and the end portion of the substrate on the application end side, and a uniform film thickness cannot be obtained in the substrate surface. In the meantime, as the coating progresses, the liquid level of the coating liquid stored in the storage portion is lowered, and the head pressure of the coating liquid acting on the discharge port 101 is reduced, and the discharge amount is gradually reduced.

The present invention has been made in view of the circumstances, and an object thereof is to uniformly apply a coating liquid having a high viscosity to a substrate without wasting.

In order to achieve the above object, the present invention relates to a coating processing apparatus which forms a liquid mixture of a coating liquid discharged from the discharge port between a substrate and a discharge port of a coating nozzle, and in this state, the substrate and the coating nozzle are provided. The coating liquid is applied to the substrate so as to be relatively movable in the horizontal direction, and has a coating nozzle including a storage chamber that communicates with the discharge port and stores the coating liquid therein, and a pressure adjusting mechanism for adjusting the aforementioned The control unit controls the pressure adjustment mechanism to adjust the pressure inside the storage chamber to the discharge amount of the coating liquid from the discharge port while the coating liquid is applied to the surface of the substrate. .

According to the present invention, when the coating nozzle and the substrate are relatively moved, the pressure adjusting mechanism is controlled while the coating liquid is applied to the substrate, and the pressure inside the storage chamber is adjusted so that the discharge amount of the coating liquid from the discharge port becomes Certainly, a uniform coating film can be formed in the surface of the substrate. Further, for example, the liquid formed in the discharge port can be sucked up to the storage chamber side so as to adjust the pressure inside the storage chamber. Thus, for example, to handle high viscosity When the coating liquid is expanded to widen the width of the discharge port, it is possible to prevent the film thickness from being lowered when the liquid droplets are dropped or applied from the discharge port. Thereby, the high viscosity coating liquid can be uniformly applied to the substrate without wasting.

The control unit may control the pressure adjustment mechanism during the application of the coating liquid on the substrate, and the pressure in the storage chamber may be a negative pressure against the pressure in the storage chamber, and the pressure in the storage chamber may be gradually increased. The discharge amount of the coating liquid from the discharge port is made constant.

A liquid level measuring mechanism for measuring a liquid level of the coating liquid stored in the storage chamber, wherein the control unit is configured to reduce a liquid level measured by the liquid level measuring unit. The pressure adjustment mechanism is controlled such that the discharge amount of the coating liquid from the discharge port is constant in a manner in which the pressure in the storage chamber rises.

A pressure measuring mechanism for measuring a pressure difference between the pressure inside the storage chamber and a pressure outside the storage chamber, wherein the control portion corresponds to a decrease in the liquid level measured by the liquid level measuring mechanism. The pressure adjusting mechanism is controlled such that the amount of discharge of the coating liquid from the discharge port is constant.

The control unit may control the pressure adjustment mechanism in accordance with the relative movement of the coating nozzle and the substrate, and change the pressure inside the storage chamber in accordance with a predetermined amplitude and a predetermined period.

According to another aspect of the invention, there is provided a coating treatment method for forming a liquid mixture of a coating liquid discharged from the discharge port between a substrate and a discharge port of a coating nozzle, and in this state, the substrate and the coating nozzle are horizontal direction The coating liquid is applied to the substrate, and the coating nozzle is provided with a storage chamber, and the storage chamber communicates with the discharge port and stores the coating liquid therein, and the coating liquid is applied to the surface of the substrate. The pressure inside the storage chamber is adjusted so that the discharge amount of the coating liquid from the discharge port is constant.

While the coating liquid is applied to the substrate, the pressure inside the storage chamber may be a negative pressure with respect to the pressure in the storage chamber, and the pressure in the storage chamber may be gradually increased to allow the pressure from the discharge port. The discharge amount of the coating liquid is constant.

The liquid level of the coating liquid stored in the storage chamber may be measured, and the pressure in the storage chamber may be increased so that the pressure in the storage chamber increases in accordance with the amount of decrease in the liquid level. The discharge amount of the coating liquid is constant.

The pressure difference between the pressure inside the storage chamber and the pressure outside the storage chamber may be measured such that the pressure difference is adjusted in accordance with the amount of decrease in the liquid level measured by the liquid level measuring means to adjust the storage. The pressure in the interior portion makes the discharge amount of the coating liquid from the discharge port constant.

The pressure inside the storage chamber may be changed in accordance with a predetermined amplitude and a predetermined period in accordance with the relative movement of the coating nozzle and the substrate.

According to another aspect of the invention, in order to execute the coating processing method by a coating processing apparatus, a program for operating on a computer that controls a control unit of the coating processing apparatus is provided.

According to another aspect of the present invention, there is provided a program for storing the aforementioned program Readable computer memory media.

According to the present invention, a coating liquid having a high viscosity can be uniformly applied onto a substrate without wasting.

Hereinafter, embodiments of the present invention will be described. Fig. 1 is a schematic longitudinal cross-sectional view showing a configuration of a resist coating device 1 as a coating processing apparatus according to the present embodiment. Fig. 2 is a schematic cross-sectional view showing the structure of the resist coating device 1.

As shown in FIG. 1, the resist coating device 1 has a processing container 10. The processing container 10 is internally provided with a rotating jig 20 for holding the wafer W for rotation. The rotating jig 20 has a horizontal upper surface on which a suction port (not shown) for sucking the wafer W is provided, for example. The wafer W can be adsorbed and held by the rotating jig 20 by suction from the suction port.

The rotating jig 20 has, for example, a jig driving mechanism 21 including a motor, and the jig driving mechanism 21 can be rotated at a predetermined speed. Further, the jig drive mechanism 21 is provided with a lift drive source such as a cylinder, and the rotary jig 20 can be moved up and down.

A cup 22 is provided around the rotating jig 20 for receiving and recovering the liquid scattered or dropped from the wafer W. A discharge pipe 23 for discharging the recovered liquid is connected to the lower surface of the cup 22, and the atmosphere in the cup 22 is arranged. Gas exhaust pipe 24.

As shown in Fig. 2, a rail 30 extending in the Y direction (the horizontal direction in Fig. 2) is formed on the side of the cup 22 in the negative X direction (the lower direction in Fig. 2). The rail 30 is formed, for example, from the outside in the negative direction of the Y direction of the cup 22 (the left direction in FIG. 2) to the outside in the positive direction of the Y direction (the right direction in FIG. 2). The rail 30 is mounted, for example, with two arms 31, 32.

As shown in FIGS. 1 and 2, the first arm 31 supports a coating nozzle 33 for supplying, for example, a resist liquid as a coating liquid to the wafer W. The configuration of the coating nozzle 33 will be described later.

As shown in FIG. 2, the first arm 31 is freely movable on the rail 30 by the nozzle driving portion 34 as a moving mechanism. Thereby, the coating nozzle 33 can be moved from the standby portion 35 provided on the outer side in the positive direction of the cup 22 to the upper portion of the wafer W in the cup 22, and further on the surface of the wafer W. The upper side moves in the radial direction of the wafer W. Further, the first arm 31 can be freely moved up and down by the nozzle driving unit 34, and the height of the coating nozzle 33 can be adjusted. The nozzle drive unit 34 incorporates, for example, a rotary encoder (not shown) for detecting position information of the nozzle drive unit 34.

As shown in FIG. 1, the coating nozzle 33 is connected to a resist reservoir 36 in which a resist liquid is stored through a supply pipe 37. The supply pipe 37 is provided with a valve 38.

The second arm 32 supports a solvent nozzle 40 for supplying a solvent such as a diluent for the resist liquid. As shown in FIG. 2, the second arm 32 is freely movable on the rail 30 by the nozzle driving unit 41, and the solvent nozzle 40 can be moved from the standby unit 42 provided on the outer side in the negative direction of the Y direction of the cup 22. It is above the center of the wafer W in the cup 22. Moreover, the second arm 32 can be The nozzle driving unit 41 is freely movable up and down, and the height of the solvent nozzle 40 can be adjusted.

As shown in FIG. 1, the solvent nozzle 40 is connected to the solvent supply source 43 through the supply pipe 44 to supply the solvent to the solvent nozzle 40. The supply pipe 44 is provided with a supply machine group 45, and includes a pipe for controlling the flow of the solvent, a flow rate adjusting unit, and the like.

Next, in explaining the configuration of the coating nozzle 33, the principle of the present invention will be briefly explained first.

For example, as shown in FIG. 3, in the case where the liquid L of a predetermined viscosity is sandwiched by two parallel flat plates 50, 50 which are arranged side by side with a predetermined length C, as long as the gravity F1 and the liquid acting on the liquid L are applied. L has a surface tension F2 which is equalized, and the liquid L is held at a lower end between the flat plates 50 and 50 in a state in which a convex liquid La is formed downward.

Further, when the portion of the liquid leaching La of the liquid L sandwiched between the flat plates 50 and 50 is brought into contact with the object 51 to be coated such as a substrate, the surface tension of the liquid L at the contact portion is lost, so that the liquid L flows out to the object to be coated. The surface of 51, for example, as shown in Fig. 4, is formed with a fluid La between the flat plates 50, 50 and the object to be coated 51. In this state, when the flat plates 50 and 50 and the object 51 are relatively moved, the liquid L is continuously discharged from the gap C of the flat plates 50 and 50 to the object 51, and the surface of the object 51 can be coated. Coating liquid L.

However, if the viscosity of the liquid L is high, it is difficult for the liquid L to fall between the liquid L and the flat plates 50, 50. Therefore, even if the flat plates 50, 50 are moved, the liquid L does not smoothly flow out, and there is a case where uneven coating occurs. In this case, by expanding the length C of the gap between the plates 50, 50, the flow of the liquid L can be improved.

However, when the gap length C between the flat plates 50 and 50 is enlarged, the surface tension F2 of the liquid L is lowered. Further, if the surface tension F2 becomes smaller than the gravity F1, the liquid L cannot be held by the flat plates 50, 50. As a result, the liquid L is dropped from between the plates 50 and 50.

Therefore, the inventors of the present invention paid attention to the fact that the force for lifting the liquid L upward is applied from the outside, and the magnitude of the force applied from the outside is adjusted, and the sum of the applied force and the surface tension F2 is equalized to the gravity F1, that is, The flow of the liquid L can be kept parallel to the holding of the liquid L by the plates 50, 50. Specifically, for example, as shown in FIG. 5, the upper end portion and the side end portion (not shown) between the flat plates 50 and 50 are closed by the cover 52, and the area surrounded by the cover 52, the flat plates 50, 50, and the liquid L is closed. The internal pressure Px1 of M is smaller than the external pressure Px2 of the region M. In this way, the pressure from the outside of the region M toward the inside and the size (Px2-Px1) can be applied to the liquid L. Further, by adjusting the magnitude of the pressure (Px2-Px1), the sum of the upward pressure and the surface tension F2 and the gravity F1 acting on the liquid L can be equalized at the lower end between the plates 50 and 50. The state in which the convex effusion La is formed maintains the liquid L.

Moreover, according to the verification by the inventors of the present invention, after coating by the above method, it was confirmed that the film thickness of the applied liquid L was different at the end portion on the application start side and the end portion on the coating end side of the object 51. Since the liquid level of the liquid L held between the flat plates 50 and 50 is lowered as the coating progresses, the head pressure of the liquid L at the lower end portion of the flat plate 50 is reduced, and The amount of liquid L flowing out between the plates 50 and 50 is gradually reduced.

Therefore, the inventors of the present invention have focused on the fact that the pressure Px1 inside the region M of the liquid L held between the plates 50 and 50 is gradually reduced in accordance with the liquid level of the liquid L. The head pressure of the liquid L at the lower end portions of 50 and 50 is kept constant, whereby the amount of the liquid L flowing out from between the flat plates 50 and 50 can be kept constant.

The coating nozzle 33 relating to the resist coating apparatus 1 of the present invention is based on such a concept, and the configuration of the coating nozzle 33 will be described next.

For example, as shown in FIGS. 2 and 6, the entire coating nozzle 33 has an elongated shape, and the length J has, for example, a body portion 60 which is at least larger than the diameter of the wafer W. The lower end surface of the main body portion 60 is formed with a slit-shaped discharge port 61 along a longitudinal direction of the main body portion 60, for example, a predetermined length D that is larger than the diameter of the wafer W and has a predetermined width G. Slit-like.

For example, as shown in FIG. 7, the cross-sectional shape in the case where the main body portion 60 is cut in a plane orthogonal to the longitudinal direction of the main body portion 60 has a substantially U-shape. The interior of the body portion 60 forms a storage chamber 62 for storing the resist liquid R. The length of the storage chamber 62 along the longitudinal direction of the body portion 60 is the same as the length D of the discharge port 61. The lower end portion of the storage chamber 62 communicates with the resist liquid flow path 63, and the resist liquid flow path 63 extends in the vertical direction and communicates with the discharge port 61. The width of the resist liquid flow path 63 is the same as the width G of the discharge port 61. Further, the length of the resist liquid flow path 63 along the longitudinal direction of the main body portion 60 is also the same as the length D of the discharge port 61 and the storage chamber 62. Further, the discharge port 61 and the resist liquid flow path 63 formed at a predetermined width G have the same function as the above-described flat plate 50, and fall from the storage chamber 62 to the resist liquid by its own weight. The resist liquid R of the flow path 63 is sandwiched between the discharge port 61 and the resist liquid flow path 63. Further, the main body portion 60 is made of, for example, stainless steel or the like which is excellent in wettability with the resist liquid R. Moreover, in order to further improve the wettability with the resist liquid R, a resin layer may be formed on the inner surfaces of the main body portion 60, that is, the inner surfaces of the discharge port 61, the storage chamber 62, and the resist liquid flow path 63.

Further, the value of the width G of the discharge port 61 is set such that when the pressure inside the storage chamber 62 is equal to the pressure outside the storage chamber 62, the surface tension of the resist liquid R becomes higher than that acting on the resist liquid. The gravity of R is small, and the resist liquid R is dripped from the discharge port 61 at a predetermined flow rate. Further, in the experiment performed in advance, the width G, the viscosity of the resist liquid R, and the material of the main body portion 60 are changed, and the state of the resist liquid R in this case is evaluated, thereby obtaining the predetermined width. G.

For example, as shown in FIG. 7, the cross-sectional shape of the storage chamber 62 is formed in a rectangular shape having a predetermined width K and height H. Therefore, the storage chamber 62 can temporarily store the resist liquid R having a capacity of "width K x height H x length D". Further, a lid body 64 for blocking the storage chamber 62 is provided at the upper end of the body portion 60. Thereby, the liquid surface of the resist liquid R stored in the storage chamber 62, the inner wall surface of the storage chamber 62, and the area surrounded by the lid body 64 form a sealed space S. Further, the capacity of the resist liquid R stored in the storage chamber 62 can be arbitrarily set as long as it can be applied to the entire surface of the wafer W at least once or more than the resist liquid R. In addition, the shape of the storage chamber 62 is not limited to a rectangular shape as long as it can apply the capacity of the resist liquid R at least once or more to the entire surface of the wafer W, and can be arbitrarily set.

The cover body 64 is respectively provided with: for measuring the pressure in the sealed space S The pressure measuring mechanism 70, the pressure adjusting tube 72 connected to the pressure adjusting mechanism 71 for adjusting the pressure in the sealed space S, and the liquid level for measuring the liquid level of the resist liquid R in the storage chamber 62 The measuring mechanism 73 passes through the lid body 64, for example. The pressure measuring mechanism 70 and the liquid level measuring mechanism 73 are electrically connected to a control unit 150 to be described later, and the measurement results are sequentially input to the control unit 150. Further, the pressure measuring mechanism 70 or the pressure adjusting tube 72 may be any arrangement as long as it can communicate with the sealed space S, and may be provided, for example, to penetrate the side surface of the body portion 60. Further, the liquid level measuring means 73 may be any form or configuration as long as it can measure the liquid level of the resist liquid R.

As shown in FIG. 7, the pressure adjusting mechanism 71 is configured such that an exhaust mechanism 80 such as a vacuum pump and a gas supply source 81 that supplies a gas such as nitrogen are connected to the pressure adjusting pipe 72 through the switching valve 82. The pressure adjustment mechanism 71 is also electrically connected to a control unit 150 which will be described later. Further, by adjusting the degree of opening of the switching tube 82 in accordance with an instruction from the control unit 150, any one of the exhaust mechanism 80 or the gas supply source 81 is connected to the pressure adjusting tube 72, and the inside from the storage chamber 62 can be adjusted. The amount of exhaust gas or the amount of gas supplied into the storage chamber 62 is adjusted. Thereby, the pressure adjusting mechanism 71 can adjust the indicated value of the pressure measuring mechanism 70, that is, the pressure in the storage chamber 62 to a predetermined value.

In this case, the inside of the storage chamber 62 is evacuated so that the pressure in the storage chamber 62 becomes a negative pressure to the pressure outside the storage chamber 62, and the resist liquid R in the storage chamber 62 can be directed toward Lifting up to prevent the resist liquid R from dripping from the discharge port 61. Also, to supply gas to the storage chamber In the method of 62, after the resist is applied, the resist liquid R remaining in the storage chamber 62 is press-pressed or cleaned. In addition, the configuration of the pressure adjusting pipe 72 or the switching pipe 82 in the pressure adjusting mechanism 61 is not limited to the embodiment, and the configuration can be arbitrarily set as long as the pressure in the storage chamber 62 can be controlled. For example, a pressure adjustment pipe 72 and a pressure adjustment valve may be provided in the exhaust mechanism 80 and the gas supply source 81, respectively, and may be individually connected to the lid body 64.

Further, the main body portion 60 is provided with the above-described supply pipe 37 that communicates with the storage chamber 62. Therefore, the valve 38 provided in the supply pipe 37 is opened, and in this state, the pressure inside the storage chamber 62, that is, the pressure in the sealed space S by the exhaust mechanism 80, becomes a negative pressure to the outside of the main body portion 60. In this manner, the resist liquid stored in the resist reservoir 36 can be introduced into the interior of the storage chamber 62.

The resist coating apparatus 1 is provided with a control unit 150 for performing various controls such as a rotation operation and a vertical movement of the rotation jig 20, a movement operation of the coating nozzle 33 by the nozzle driving unit 34, and a pressure adjustment mechanism 71 by the pressure adjustment mechanism 71. The pressure adjustment in the storage chamber 62 is performed. The control unit 150 is constituted by, for example, a computer including a CPU and a memory. For example, by performing a program stored in the memory, the coating process of the resist coating device 1 can be realized. Further, various programs for realizing the coating process of the resist coating device 1 include, for example, a computer readable hard disk (HD), a floppy disk (FD), a compact disk (DC), a magneto-optical disk (MO), a memory card, and the like. The program stored in the memory medium H is a program that is imported from the memory medium H into the control unit 150.

Next, the description will be made regarding the use of the resist coating device 1 constructed as above. The coating process of the line. Fig. 8 is a flow chart showing an example of the main steps of the coating process. Fig. 9 is a time chart in which the vertical axis represents the state of each machine in the coating process, and the horizontal axis represents the passage of time, and changes in the state of each machine are displayed in time series.

When the coating process is performed, the wafer W is first carried into the processing container 10 of the resist coating device 1 by a transfer mechanism (not shown). The wafer W carried into the resist coating device 1 is sucked and held by the rotating jig 20.

Then, the solvent nozzle 40 of the standby unit 42 is moved to the upper side of the center portion of the wafer W by the second arm 32, and the solvent is supplied to the upper surface of the wafer W (step S1 of FIG. 8). Then, the jig drive mechanism 21 is controlled to rotate the wafer W by, for example, a rotation number of 500 rpm by the rotation jig 20 so that the solvent supplied to the center portion of the wafer W is diffused toward the outer peripheral portion of the wafer W (step S2 of FIG. 8). ). Thereby, the surface of the wafer W is in a state of being wetted by the solvent. Then, after the solvent is diffused to the entire surface of the wafer W, the solvent nozzle 40 is evacuated from the upper portion of the wafer W to the standby portion 42. The rotating jig 20 also stops rotating therewith.

Then, the coating nozzle 33 of the standby unit 35 is moved by the first arm 31 to the end of the wafer W, for example, the end portion on the positive side in the Y direction of FIG. 2 (step S3 in FIG. 8 and time T1 in FIG. 9). . At this time, the pressure adjustment mechanism 71 is adjusted to a predetermined pressure P0 in advance, and the inside of the storage chamber 62 of the coating nozzle 33 is brought to a negative pressure to the outside of the storage chamber 62. Further, in the present embodiment, the pressure outside the storage chamber 62 is, for example, a constant atmospheric pressure.

Next, the valve 38 provided in the supply pipe 37 is opened. Through this The supply pipe 37 introduces the resist liquid R from the resist reservoir 36 into the storage chamber 62 of the coating nozzle 33. Thereby, the liquid level of the resist liquid R stored in the height H0 before the introduction is raised to the height H1, and the predetermined amount of the resist liquid R is stored in the storage chamber 62 (step S4 of FIG. 8 and time T2 of FIG. 9). At this time, the amount of the resist liquid R stored in the storage chamber 62 is at least one time that the resist W can be applied to the wafer W more than once. The amount of the resist liquid R introduced into the storage chamber 62 is determined based on the liquid level of the resist liquid R measured by the liquid level measuring unit 73, the width K of the storage chamber 62, and the length D. Further, the volume of the resist liquid flow path 63 is extremely small compared to the volume of the storage chamber 62. Therefore, the amount of the resist liquid R stored in the resist liquid flow path 63 can be ignored. Further, in the case of the wafer W having a diameter of 300 mm, the resist liquid for the primary resist coating is, for example, 7 cc.

After a predetermined amount of the resist liquid is stored in the storage chamber 62, the valve 38 is closed (time T3 in Fig. 9). Further, the replenishing liquid R may be added to the storage chamber 62, or may be performed before moving the coating nozzle 33 to the end of the wafer W.

Next, the coating nozzle 33 is lowered toward the wafer W. For example, as shown in FIG. 10, the discharge port 61 and the wafer W are brought close to a predetermined distance Z1 (time T4 in FIG. 9). Then, the pressure adjustment mechanism 71 raises the pressure of the sealed space S in the storage chamber 62 to a predetermined value P1 (the degree of vacuum is lowered) (time T5 in FIG. 9). Thereby, the resist liquid R held by the resist liquid flow path 63 and the discharge port 61 is dropped by the surface tension of the resist liquid R and the negative pressure in the sealed space S, for example, as shown in FIG. The effluent Ra of the resist liquid R is formed between the end portion and the discharge port 61 (step S5 of Fig. 8).

Then, the pressure in the sealed space S is directly lowered to P2 (the degree of vacuum rises), so that the resist liquid R does not flow out from the discharge port 61 onto the wafer W. The coating nozzle 33 is raised together with the distance between the discharge port 61 and the wafer W to be Z2 (time T6 in Fig. 9). In addition, the distance Z2 is obtained by maintaining the effusion Ra of the resist liquid R formed between the wafer W and the lower end surface of the main body portion 60 at a distance that does not break, and is obtained by an experiment or the like performed in advance.

Then, as shown in FIG. 12, the applicator nozzle 33 is moved to the end of the standby portion 42 side of the wafer W (the negative side in the Y direction of FIG. 2) at a predetermined speed by the first arm 31 (FIG. 8). Step S6 and time T6~T7 of FIG. Thereby, the resist liquid R of the storage chamber 62 flows out from the discharge port 61, and the resist liquid R is applied to the surface of the wafer W. At this time, the pressure of the sealed space S is gradually increased from P2 to P3 by the pressure adjusting mechanism 71 in accordance with the decrease in the liquid level of the resist liquid R in the storage chamber 62.

As described above, once the liquid level of the resist liquid R in the storage chamber 62 is lowered, the head pressure of the resist liquid R acting on the discharge port 61 is reduced. During this period, if the pressure in the sealed space S of the storage chamber 62 and the pressure outside the storage chamber 62 are set to be constant and constant, the force for pressing the resist liquid R from the discharge port 61 is just to reduce the decrease in the head pressure. Therefore, the amount of discharge of the resist liquid R is reduced.

Therefore, in the present embodiment, the pressure of the sealed space S is gradually increased to, for example, P3 by the pressure adjusting mechanism 71 in accordance with the decrease in the liquid level of the resist liquid R in the storage chamber 62 (the degree of vacuum is lowered). In this manner, the head pressure of the discharge port 61 due to the reduction in the liquid level is reduced. Its knot As a result, the discharge amount of the resist liquid R discharged from the discharge port 61 is kept constant, and a resist film having a uniform film thickness is formed in the surface of the wafer W. At this time, the value of the pressure in the sealed space S which is raised by the pressure adjusting mechanism 71 is obtained, for example, from the height of the liquid surface of the resist liquid R measured by the liquid level measuring means 73. Specifically, the amount of difference between the liquid level before the start of application and the height of the liquid surface after the start of application is determined, and the liquid level before the start of application is the state before the start of application (for example, time T6 in FIG. 9). The liquid level of the resist liquid R, the liquid level after the start of the coating is the resist in the storage chamber 62 after the application of the coating nozzle 33 to the wafer W by a predetermined distance to apply the resist liquid R. The liquid level of the resist liquid R in a state where the liquid R is reduced. Further, the amount of decrease in the head pressure associated with the discharge port 61 can be obtained by multiplying the amount of the difference in the height by the density of the resist liquid R. Therefore, the pressure in the sealed space S is increased by the pressure adjusting mechanism 71 so that the head pressure associated with the discharge port 61 is constant between time T6 and time T7. Therefore, the discharge amount of the resist liquid R discharged from the discharge port 61 is constant, and a resist film having a uniform film thickness is formed in the surface of the wafer W.

Further, the adjustment of the pressure in the sealed space S does not necessarily have to be performed in accordance with the liquid level of the resist liquid R in the storage chamber 62. For example, the sealed space can be adjusted corresponding to the relative movement distance of the coating nozzle 33 and the wafer W. The pressure inside S. In this case, as shown in FIG. 13, the correlation between the moving distance of the coating nozzle 33 and the pressure setting value in the sealed space S can be obtained in advance, and the pressure in the sealed space S can be adjusted based on the correlation.

In a manner related to FIG. 13 in advance, according to the coating nozzle 33 The amount of consumption of the resist liquid R at a predetermined position of the wafer W is obtained by determining the amount of decrease in the head pressure, whereby the pressure in the sealed space S can be adjusted. Moreover, the amount of discharge of the resist liquid R from the discharge port 61 is made constant. For example, another pressure measuring means is provided in the resist liquid flow path 63, and the resistance acting on the resist liquid flow path 63 is directly determined. The head pressure of the solution liquid R is adjusted by the pressure adjusting mechanism 71 to adjust the pressure in the sealed space S to make the head pressure constant. In either case, the pressure inside the storage chamber 62 can be adjusted by the pressure adjusting mechanism 71 to make the discharge amount of the resist liquid R from the discharge port 61 constant, in other words, the resist liquid acting on the discharge port 61. Since the head pressure of R is constant, a resist film having a uniform film thickness can be formed in the W surface of the wafer.

When the coating nozzle 33 moves to the end of the standby portion 42 side of the wafer W (the negative side in the Y direction of FIG. 2) (time T7 in FIG. 9), the coating nozzle 33 is lowered, and the discharge port 61 and the wafer W are caused. Close to the distance Z1. In conjunction with this, the pressure adjusting mechanism 71 lowers the pressure in the sealed space S to, for example, P0 (the degree of vacuum rises), and introduces the resist liquid into the storage chamber 62 side. Thereby, the liquid hydride Ra formed between the wafer W and the lower end surface of the main body portion 60 is eliminated, and the supply of the resist liquid to the wafer W from the discharge port 61 is stopped.

Then, the pressure in the sealed space S is again raised to, for example, P3 (the degree of vacuum is lowered), and the coating nozzle 33 is raised to a predetermined height (time T8 in FIG. 9). Next, the coating nozzle 33 is retracted to the standby unit 35 (step S7 of FIG. 8 and time T9 of FIG. 9). In addition, the pressure of the closed space S is again raised to P3 at time T8, in order to be once The resist liquid R applied to the wafer W is introduced into the storage chamber 62 side to prevent coating defects from occurring.

Then, the rotating jig 20 is rotated at, for example, 1000 rpm to 1800 rpm. In the present embodiment, the entire resist liquid applied to the surface of the wafer W is dried by rotating at 1500 rpm (step S8 in Fig. 5). Thereby, a resist film is formed on the wafer W.

Then, the wafer W is carried out from the processing container 10 by a transfer mechanism (not shown), and the series of coating processes is terminated, and the coating process is repeated.

According to the above embodiment, while the application nozzle 33 and the wafer W are relatively moved to apply the resist liquid R to the wafer, the pressure adjusting mechanism 71 adjusts the pressure inside the storage chamber 62 to make the discharge port. Since the discharge amount of the resist liquid R of 61 is constant, a resist film having a uniform film thickness can be formed in the surface of the wafer W. Moreover, by adjusting the pressure inside the storage chamber 62, the liquid accumulated in the slit-shaped discharge port 61 can be sucked up to the storage chamber 62 side and appropriately held. Therefore, it is possible to prevent a film thickness from being lowered from the discharge port or the film thickness at the time of application of the resist.

In particular, since the actual liquid level is measured by the liquid level measuring means 73, the liquid level of the resist liquid R corresponding to the storage chamber 62 is reduced, and the pressure inside the storage chamber 62 is increased by the pressure adjusting mechanism 71. That is, the pressure in the sealed space S can control the supply amount of the resist liquid more precisely.

In the above embodiment, the coating nozzle 33 and the wafer W are relatively moved so that the coating nozzle 33 moves. However, for example, the coating nozzle 33 may be fixed. In the state of the horizontal position, the wafer W is moved to the coating nozzle 33.

In the above embodiment, for example, the pressure in the sealed space S is adjusted in accordance with the liquid level of the storage chamber 62. However, in addition to the pressure control corresponding to the liquid level, for example, as shown in FIG. 14, the sealing may be performed in accordance with a predetermined amplitude and a predetermined period. The pressure change in space S. When the pressure in the sealed space S is changed in a periodic function, the resist liquid R in the storage chamber 62 alternately acts on the force that pulls up the resist liquid R upward and the force that is pushed downward. Thereby, for example, similarly to the case where the main body portion 60 is vibrated in the vertical direction, the fluidity of the resist liquid R in the storage chamber 62, particularly in contact with the storage chamber 62 and the resist liquid flow path 63, can be improved. The resist liquid R is smoothly supplied from the discharge port 61. As a result, even when a coating liquid having a high viscosity is used, uneven coating can be suppressed.

Further, in the above embodiment, after the application of the resist liquid R, for example, at time T7, the coating liquid 33 is lowered at the end of the wafer W, and the pressure of the sealed space S is lowered to P0 to eliminate the liquid ef Ra, but for example. Alternatively, the height of the coating nozzle 33 can be changed, and the coating nozzle 33 can be directly passed through the end of the wafer W to eliminate the liquid accumulation Ra.

In the above embodiment, the resist liquid flow path 63 is provided along the vertical direction, but it may be provided, for example, by tilting at a predetermined angle. As a result, the resistance of the resist liquid R when passing through the resist liquid flow path 63 is increased, so that the flow rate change of the resist liquid R flowing out from the discharge port 61 can be made smaller than the change in the pressure in the sealed space S. . In other words, the sensitivity of the pressure adjustment mechanism 71 to the control of the discharge amount from the coating nozzle 33 can be reduced. It is assumed that in the case where the sensitivity of the control is too high, for example, it is necessary to treat the resist liquid R in the storage chamber 62. The liquid level is closely and consistently set to the pressure. However, as long as the sensitivity of the control is lowered, even if the pressure in the sealed space S deviates somewhat from the set value, since the influence of the discharge amount from the coating nozzle 33 is small, it can be derived from The discharge amount of the discharge port 61 changes smoothly.

Further, in the above embodiment, the case where the pressure outside the storage chamber 62 is constant at atmospheric pressure will be described. However, for example, the pressure of the atmosphere of the resist application device 1 is disposed, and for example, the air pressure in the clean room is changed depending on, for example, temperature or weather. So it is not always a certain. Further, even if the pressure inside the storage chamber 62, that is, the pressure in the sealed space S is adjusted to a predetermined value, when the external pressure fluctuates, the discharge amount of the resist liquid R from the discharge port 61 does not become a desired value. Therefore, as the pressure measuring mechanism 70, a differential pressure gauge that measures the pressure difference inside the storage chamber 62 and outside the storage chamber 62 can also be used. In this case, the pressure adjusting mechanism 71 adjusts the pressure in the storage chamber 62, that is, the pressure in the sealed space S, in accordance with the ratio of the liquid level of the resist liquid R in the storage chamber 62 during the application of the resist, so that the storage chamber 62 is provided. The pressure difference between inside and outside is reduced.

[Examples]

In the case of performing the resist coating by the coating processing apparatus 1 according to the present embodiment, for example, the pressure in the sealed space S is changed by, for example, the liquid level of the resist liquid R in the storage chamber 62. An experiment for confirming the film thickness of the resist film after coating was performed. Further, as a comparative example, a confirmation experiment was also performed in the case where the pressure in the storage chamber 62, that is, the pressure in the sealed space S, was kept constant during the application. At this time, by The distance Z2 between the discharge port 61 and the wafer W when the coating nozzle 33 is subjected to the coating process is, for example, 60 μm, and the wafer W is used as a 300 mm diameter. The viscosity of the resist liquid R as a coating liquid, for example, 1800 mPa. s.

The experimental results are shown in Figures 15 and 16. The vertical axis of FIGS. 15 and 16 is the film thickness, and the horizontal axis is the position of the wafer W in the radial direction. Fig. 15 is a table showing the film thickness of the resist film in the case where the pressure in the sealed space S is constant during coating. Fig. 16 is a table showing the film thickness of the resist film in the case where the pressure in the sealed space S is changed to match the liquid level of the resist liquid R. Further, as another embodiment, as shown in FIG. 14, an experiment for confirming the film thickness of the resist film when the pressure in the sealed space S is changed to a predetermined amplitude, a predetermined period, and a periodic function is performed. The amplitude of the pressure change is 100 Pa and the period is about 1 second. The result is shown in Fig. 17. Further, in Table A shown in Figs. 15, 16, and 17, the film thickness of the resist film was measured along the moving direction of the coating nozzle 33. Table B is perpendicular to the moving direction of the coating nozzle 33, that is, the film thickness of the resist film is measured along the longitudinal direction of the coating nozzle 33.

As shown in Fig. 15, the pressure in the sealed space S is kept constant during coating, and the pattern A is sagged to the right, and it can be confirmed that the resist liquid R in the storage chamber 62 is reduced, and the resistance from the discharge port 61 is blocked. The discharge amount of the solution liquid R is reduced. Further, the pattern B, that is, the film thickness along the longitudinal direction of the coating nozzle 33 is substantially equal.

On the other hand, when the pressure in the sealed space S is changed to match the liquid level of the resist liquid R, it can be confirmed that any of the patterns A and B can obtain a uniform film thickness in the wafer W surface.

Further, in the case where the pressure in the sealed space S is changed in a periodic function, a plurality of film thickness unevenness is observed at the end portion of the wafer W, but the pressure in the sealed space S is kept constant during coating. It can be confirmed that good results are obtained. Therefore, according to the resist coating apparatus 1 according to the present embodiment, it has been confirmed that the coating liquid having a high viscosity can be uniformly applied onto the wafer W without being wasted.

Although the preferred embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited by the examples. As long as it is a person skilled in the art, it is obvious that various modifications and modifications can be made without departing from the scope of the invention as set forth in the appended claims. The present invention is not limited to this example and can adopt various aspects. For example, the present invention is also applicable to the case where a resist liquid is used instead of other high-viscosity coating liquids such as polyimide. Further, although the above embodiment is an example in which a wafer is subjected to a coating process, the present invention can also be applied to a case where the substrate is an FPD (flat display) other than the wafer, or another substrate such as a mask original for a mask (Mask Reticle). .

[Industrial availability]

The present invention is useful, for example, when a coating liquid having a high viscosity is applied onto a substrate such as a semiconductor wafer.

1‧‧‧Resistant coating device

10‧‧‧Processing container

20‧‧‧Rotary fixture

21‧‧‧Clamp drive mechanism

22‧‧‧ cup

23‧‧‧Draining tube

24‧‧‧Exhaust pipe

30‧‧‧ Track

31, 32‧‧‧ arms

33‧‧‧Applicator mouth

34‧‧‧Nozzle Drive Department

35, 42‧‧ ‧ Standby Department

36‧‧‧Resistor storage tank

37, 44‧‧‧ supply tube

38‧‧‧ tube

40‧‧‧pure water nozzle

41‧‧‧Nozzle Drive Department

43‧‧‧ pure water supply source

50‧‧‧ tablet

51‧‧‧ coated objects

52‧‧‧ Cover

60‧‧‧ Body Department

61‧‧‧Exporting

62‧‧‧Retention room

63‧‧‧Resistant flow path

64‧‧‧ Cover

70‧‧‧ Pressure measuring agency

71‧‧‧ Pressure adjustment mechanism

72‧‧‧pressure adjustment tube

73‧‧‧Liquid height measuring mechanism

80‧‧‧Exhaust mechanism

81‧‧‧ gas supply

82‧‧‧Switch tube

150‧‧‧Control Department

A, C, D, J‧‧‧ length

G, K‧‧ wide

L‧‧‧Liquid

R‧‧‧Resistant

W‧‧‧ wafer

Z‧‧‧ distance

Fig. 1 is a schematic longitudinal cross-sectional view showing a configuration of a coating processing apparatus according to the present embodiment.

Fig. 2 is a schematic cross-sectional view showing the configuration of a coating processing apparatus according to the present embodiment.

Fig. 3 is an explanatory view relating to the principle of the coating nozzle.

Fig. 4 is an explanatory view relating to the principle of the coating nozzle.

Fig. 5 is an explanatory view relating to the principle of the coating nozzle.

Fig. 6 is a schematic perspective view showing the configuration of a coating nozzle.

Fig. 7 is a schematic longitudinal cross-sectional view showing the configuration of a coating nozzle as viewed from a plane orthogonal to the longitudinal direction of the coating nozzle.

Figure 8 is a flow chart showing the main steps of the coating process.

Fig. 9 is a time chart showing changes in the state of each machine in the coating process.

Fig. 10 is an explanatory view showing a state in which the coating nozzle is moved toward the upper end of the wafer.

Fig. 11 is an explanatory view showing a state in which a liquid repellency of a resist liquid is formed between a coating nozzle and an end portion of a wafer.

Fig. 12 is an explanatory view showing a state in which a resist liquid is applied to a surface of a wafer by a coating nozzle.

Fig. 13 is a table showing the correlation between the moving distance of the coating nozzle and the pressure setting value in the sealed space.

Fig. 14 is a time chart showing pressure changes in a sealed space relating to the pressure control method of the other embodiment.

Fig. 15 is a table showing the film thickness of the resist film on the wafer in the comparative example.

Figure 16 is a view showing the wafer in the embodiment related to the embodiment. The film thickness of the resist film.

Fig. 17 is a table showing the film thickness of the resist film on the wafer in the examples relating to the other embodiments.

Fig. 18 is a schematic longitudinal cross-sectional view showing a configuration of a conventional coating nozzle.

33‧‧‧Applicator mouth

37‧‧‧Supply tube

60‧‧‧ Body Department

61‧‧‧Exporting

62‧‧‧Retention room

63‧‧‧Resistant flow path

64‧‧‧ Cover

70‧‧‧ Pressure measuring agency

71‧‧‧ Pressure adjustment mechanism

72‧‧‧pressure adjustment tube

73‧‧‧Liquid height measuring mechanism

80‧‧‧Exhaust mechanism

81‧‧‧ gas supply

82‧‧‧Switch tube

150‧‧‧Control Department

G, K‧‧ wide

H‧‧‧ Height

R‧‧‧Resistant

S‧‧‧Confined space

Claims (12)

A coating processing apparatus is configured to form a liquid repellency of a coating liquid discharged from the discharge port between a substrate and a discharge port of a coating nozzle, and in this state, the substrate and the coating nozzle are relatively moved in a horizontal direction. The coating liquid is applied to a substrate, comprising: a coating nozzle having a storage chamber that communicates with the discharge port and stores a coating liquid therein; a pressure adjustment mechanism for adjusting a pressure inside the storage chamber; and a control unit When the coating liquid is applied to the surface of the substrate, the pressure inside the storage chamber is adjusted so that the discharge amount of the coating liquid from the discharge port is constant. The coating processing apparatus according to the first aspect of the invention, wherein the control unit controls the pressure adjusting mechanism to apply a pressure to the pressure inside the storage chamber to a negative pressure during the application of the coating liquid to the substrate. Further, the pressure inside the storage chamber is gradually increased so that the discharge amount of the coating liquid from the discharge port is constant. The coating processing apparatus according to claim 2, further comprising a liquid level measuring mechanism for measuring a liquid level of the coating liquid stored in the storage chamber, wherein the control unit is configured to measure the liquid level by using the liquid level The pressure adjustment mechanism is controlled such that the amount of decrease in the liquid level measured by the mechanism increases the pressure in the storage chamber, so that the discharge amount of the coating liquid from the discharge port is constant. The coating processing apparatus of claim 3, wherein the pressure measuring mechanism has a pressure measuring mechanism for measuring a pressure inside the storage chamber and the storage a pressure difference between the pressures in the outdoor unit, wherein the control unit controls the pressure adjustment mechanism so as to reduce the pressure difference corresponding to the decrease in the liquid level measured by the liquid level measuring means; The discharge amount of the coating liquid is constant. The coating processing apparatus according to claim 1, wherein the control unit controls the pressure adjusting mechanism in accordance with a relative movement of the coating nozzle and the substrate, and causes a pressure in the storage chamber to follow a predetermined amplitude and a predetermined period. And change. A coating treatment method is a method of forming a liquid mixture of a coating liquid discharged from the discharge port between a substrate and a discharge port of a coating nozzle, and in this state, the substrate and the coating nozzle are relatively moved in the horizontal direction. The coating liquid is applied to the substrate, and the coating nozzle includes a storage chamber that communicates with the discharge port and stores the coating liquid therein, and adjusts the inside of the storage chamber while the coating liquid is applied to the surface of the substrate. The pressure is such that the discharge amount of the coating liquid from the discharge port is constant. The coating treatment method according to the sixth aspect of the invention, wherein the pressure inside the storage chamber is negatively applied to the pressure inside the storage chamber during the application of the coating liquid to the substrate, and the pressure inside the storage chamber is further increased. The rise is gradually increased so that the discharge amount of the coating liquid from the discharge port is constant. The coating treatment method according to claim 7, wherein the liquid level of the coating liquid stored in the storage chamber is measured to make the aforementioned The pressure in the storage chamber is increased in accordance with the amount of decrease in the liquid level, and the pressure in the storage chamber is adjusted so that the discharge amount of the coating liquid from the discharge port is constant. The coating processing method of claim 8, wherein the pressure difference between the pressure inside the storage chamber and the pressure outside the storage chamber is measured such that the pressure difference corresponds to a liquid level measured by the liquid level measuring mechanism. In a manner in which the amount of decrease in height is reduced, the pressure inside the storage chamber is adjusted so that the discharge amount of the coating liquid from the discharge port is constant. The coating treatment method according to claim 6, wherein the pressure inside the storage chamber changes in accordance with a predetermined amplitude and a predetermined period in accordance with the relative movement of the coating nozzle and the substrate. A program for performing a coating treatment method according to any one of claims 6 to 10 by a coating processing apparatus, on a computer for controlling a control device of the coating processing apparatus. A computer memory medium is a readable computer memory medium storing a program as claimed in claim 11.