JP2002353132A - Coater and coating method of substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure flatness of resist liquid while suppressing evaporation of the solvent in the resist liquid on a wafer when the wafer is coated with the resist liquid with one stroke. SOLUTION: Covers 75 and 76 covering a wafer W are disposed in an enclosure where coating of resist liquid is carried out. A resist liquid ejection nozzle 85 movable horizontally in the direction perpendicular to the advancing direction of the wafer W, i.e., the X direction, is disposed between the covers 75 and 76. The cover 75 is supported, on the ejection nozzle 85 side, by a supporting member 77 and, on the forward side in the X direction, by a supporting member 78. The supporting member 77 can be elevated/lowered through an elevating/ lowering drive section 81. At the time of coating, the supporting member 77 is elevated for a specified distance and the cover 75 is inclined. Since the gap between the cover 75 on the ejection nozzle 85 side and the wafer W is widened, shearing stress acting onto the surface of a resist film is reduced when the wafer W moves in the X direction immediately after coating resist.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a substrate coating apparatus and a substrate coating method.

[0002]

2. Description of the Related Art For example, in a photolithography process in a semiconductor device manufacturing process, a resist solution is applied to a wafer surface to form a resist film, a resist is exposed to a pattern on the wafer, and an exposed wafer is exposed. Is performed to form a predetermined circuit pattern on the wafer.

At present, in the resist coating process,
A spin coating method in which a resist solution is discharged to the center of a rotated wafer and the resist solution is diffused on the surface of the wafer is mainly used.

[0004]

However, in the spin coating method, since the wafer is rotated at a high speed, a large amount of the resist solution is scattered from the outer edge portion of the wafer, so that much of the resist solution is wasted. In addition, since the apparatus is contaminated by the scattering of the resist solution, there are problems such as frequent cleaning.

Therefore, instead of the spin coating method in which the wafer is rotated, the resist liquid is discharged from the resist liquid discharge section while the wafer and the resist liquid discharge section are relatively moved, so that the resist liquid is uniformly distributed on the wafer in a substantially rectangular wave shape. A so-called one-stroke application method can be proposed. In the so-called one-stroke application method, for example, the resist liquid discharge section discharges the resist liquid while reciprocating on the wafer in the Y direction, and the wafer slightly moves in the X direction each time the resist liquid discharge section turns. By shifting the application position, the resist liquid is applied to the entire surface of the wafer.

On the other hand, in a so-called one-stroke application method, for example, a resist solution having a high solvent concentration and a low viscosity is used, and the resist solution is applied linearly on a wafer. However, if it is left as it is, the resist liquid will swell along the coating path, so that it is necessary to diffuse the resist liquid over the entire surface of the wafer after coating. Therefore, in order to maintain the low viscosity of the resist solution, it is necessary to cover the wafer with, for example, a lid so that the solvent in the resist solution does not evaporate. In order to effectively suppress the volatilization of the solvent, it is desirable that the lid be as close to the wafer as possible.

However, when the lid is provided on the wafer and the wafer is moved in the X direction, an airflow in the X direction is formed between the wafer and the lid. The air flow has a velocity gradient under the influence of the lid, and a shear stress is generated on the wafer surface by the velocity gradient, so that the applied state of the resist liquid immediately after application is disturbed by the shear stress. There is fear. Also, as the lid is brought closer to the wafer, the shear stress increases, and there is a concern that the flatness of the resist solution may be lost. If the flatness of the resist solution is impaired in this way, a resist film having a uniform thickness cannot be formed on the wafer, which leads to a decrease in yield.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and when a coating solution such as a resist solution is applied in a so-called one-stroke manner, the solvent of the coating solution applied to a substrate such as a wafer is evaporated. It is an object of the present invention to provide a substrate coating apparatus and a substrate coating method which ensure the flatness of a coating liquid while suppressing the occurrence of the problem.

[0009]

According to the first aspect of the present invention, there is provided a coating apparatus for applying a coating liquid to a substrate, wherein the coating liquid is reciprocated on the substrate in a predetermined direction to discharge the coating liquid to the substrate. A coating liquid discharging unit, a holding unit that holds the substrate and is horizontally movable in a direction perpendicular to the predetermined direction, and a substrate that is closer to the one direction than the coating liquid discharging unit when viewed from above. And a lid for covering the upper surface of the substrate when the substrate is moved to a lower position, wherein the lower surface of the lid is inclined so that the side of the coating liquid ejecting section becomes higher. You. Since the lower surface of the lid only needs to be inclined, a flat lid may be provided obliquely, or a lid having an inclined lower surface may be provided.

[0010] As described above, the coating liquid ejecting section that can reciprocate on the substrate in a predetermined direction and the holding section for the substrate that can move in one direction perpendicular to the predetermined direction have the following effects. It is possible to carry out a so-called one-stroke application method in which the application liquid is applied to the substrate by moving the liquid ejection part relative to the substrate and applying the application liquid uniformly on the substrate. In addition, the lid that covers the upper surface of the substrate suppresses evaporation of the solvent from the coating liquid applied to the substrate, and maintains low viscosity of the coating liquid.
Further, since the coating liquid discharge portion side of the lid is made higher, a wide gap is formed between the substrate and the lid when the substrate immediately after coating moves in the one direction side. Accordingly, when an airflow is generated in the gap due to the movement of the substrate, it is possible to suppress the application liquid from being disturbed by the airflow, and accordingly, the flatness of the application liquid is secured. In particular, when the substrate moves, the coating liquid on the substrate is dragged backward with respect to the traveling direction by the shear stress based on the velocity gradient of the airflow,
There is a concern that the coating liquid on the substrate in the traveling direction becomes thin. According to the first aspect of the present invention, since a large gap is provided between the substrate and the lid, it is possible to suppress generation of a large shear stress on the substrate surface immediately after the application, so that only the application liquid in the traveling direction becomes thin. Is suppressed. As a result, the uniformity of the thickness of the coating liquid within the substrate surface is ensured. Also, since the lid is provided diagonally, as the substrate moves in the one direction,
The gap between the lid and the cover is reduced, and unnecessary evaporation of the solvent in the coating liquid can be suppressed.

According to a second aspect of the present invention, there is provided a coating apparatus for coating a substrate with a coating liquid, the coating apparatus comprising: a coating liquid discharge unit configured to reciprocate on the substrate in a predetermined direction and discharge the coating liquid to the substrate; A holding unit that holds the substrate and is horizontally movable in one direction perpendicular to the predetermined direction, and a holding unit that moves in one direction with respect to the coating liquid ejection unit when viewed from a plane. A lid for covering the upper surface of the substrate, wherein the lower surface of the lid is inclined so that the side of the coating liquid discharge section is lower; In addition,
Since it is sufficient that the lower surface of the lid is inclined, a flat lid may be provided obliquely inclined, or a lid having an inclined lower surface may be used.

As described above, by lowering the coating liquid discharge portion side of the lid, a narrow gap is formed between the substrate and the lid when the substrate immediately after coating moves in the one direction. The shear flow formed in the gap by the movement of the substrate generates a shear stress on the surface of the coating liquid, and the coating liquid can be flattened by the shearing force. In particular, when the coating liquid is applied in a so-called one-stroke manner, the swelling of the coating liquid along the coating path is formed immediately after the coating, but the coating liquid is flattened by the shear flow, and the coating liquid is flattened. The performance is improved.

[0013] The lower surface of the above-mentioned lid may be curved. Thus, by bending the lower surface of the lid,
The airflow between the substrate and the lid flows smoothly along the curved surface,
The behavior of the airflow is stabilized. This stabilizes the coating liquid affected by the air flow, and forms an appropriate coating film on the substrate.

The lid may have a flat plate shape, and may have a lid elevating mechanism for raising and lowering a part of the lid. By providing the lid elevating mechanism in this manner, the lid can be raised and lowered a predetermined distance and the lid can be inclined. In addition, by adjusting the elevating distance, the inclination angle of the lid can be adjusted, so that the distance of the gap between the substrate and the lid can be adjusted. Therefore, by adjusting the distance appropriately, it is possible to minimize the volatilization of the solvent from the coating liquid while suppressing the influence of the air flow. Further, if the thickness of the lid is made uniform, it is possible to suppress temperature unevenness.

[0015] The lid lifting mechanism may be configured to raise and lower the vicinity of both ends of the lid in the one direction. As described above, by raising and lowering both ends of the lid, it is possible to adjust the vertical distance between the both ends and adjust the inclination angle of the lid. In addition, by raising and lowering both ends of the lid, the entire lid can be moved up and down, so that the distance between the substrate and the lid can be changed. The airflow formed between the substrate and the lid can be controlled.
Therefore, by adjusting the distance of the gap according to the type of the coating liquid and the moving speed of the substrate, the flatness of the coating liquid can be secured while suppressing the evaporation of the solvent of the coating liquid on the substrate.
In this case, the apparatus may further include a control device that controls the degree of elevation of the lid elevating mechanism based on the thickness of the coating liquid on the substrate.

According to the seventh aspect of the present invention, the step of applying the coating liquid onto the substrate while the coating liquid discharge section moves on the substrate in a predetermined direction, and the step of applying the coating liquid discharge section to the outside of the substrate. A step of moving the substrate by a predetermined distance in one direction perpendicular to the predetermined direction, and then applying the coating liquid on the substrate while the coating liquid discharge unit moves on the substrate in a direction opposite to the predetermined direction. A coating method for coating the substrate with the coating liquid being applied to the surface of the substrate, wherein a lid for covering the upper surface of the substrate is placed on the same substrate as the substrate when the substrate is moved in the one direction. Moving the cover to the original position before moving the cover when the application liquid discharging unit moves in the opposite direction to the predetermined direction to apply the coating liquid to the substrate. And a substrate coating method characterized by having a process. It is.

According to the seventh aspect, the so-called single-stroke application method is performed. When the substrate is shifted in the one direction, the lid is also moved in the same direction.
The velocity gradient of the airflow formed between the substrate and the lid is reduced by the movement of the substrate. This reduces the influence of the air flow on the coating liquid on the substrate, stabilizes the behavior of the coating liquid, and ensures the flatness of the coating liquid. Further, since the lid is moved to the original position when the coating liquid discharging section is discharging the coating liquid onto the substrate, the lid is displaced from the substrate and a large amount of the solvent on the substrate is not volatilized. In addition, the space for moving the lid can be minimized.

The speed at which the lid moves to the original position is
The speed at which the lid moves in the one direction by a predetermined distance may be lower than the speed at which the lid moves by a predetermined distance in the one direction. By returning the lid at a low speed in this way, it is possible to suppress the formation of an airflow having a velocity gradient between the substrate and the lid at this time. Therefore, the lid can be returned to the original position without adversely affecting the coating liquid on the substrate.

According to a ninth aspect of the present invention, there is provided a coating apparatus for applying a coating liquid to a substrate, wherein the coating liquid discharge section reciprocates on the substrate in a predetermined direction and discharges the coating liquid to the substrate. A holding portion that holds the substrate and is horizontally movable in a direction perpendicular to the predetermined direction, a lid that covers an upper surface of the substrate, and a lid movement that moves the lid in a direction perpendicular to the predetermined direction. And a device for applying a substrate.

By providing the lid moving device for moving the lid in a direction perpendicular to the predetermined direction, the method for coating a substrate according to the above-mentioned aspect can be suitably carried out. Therefore, the influence of the airflow formed between the substrate and the lid on the coating liquid on the substrate is reduced, the behavior of the coating liquid is stabilized, and the flatness of the coating liquid can be secured.

If the temperature of the lid can be adjusted, it is possible to control the evaporation from the coating liquid on the substrate.
In this case, the temperature of the lid is preferably adjusted in a range of 10 ° C to 23 ° C. If the temperature is lower than 10 ° C., the surface of the lid may be dewed. If the temperature exceeds 23 ° C., evaporation from the applied liquid may be accelerated.
As means for such temperature adjustment, for example, it can be proposed to form a cooling water flow path in a lid or to house a Peltier element or a heat pipe device in the lid.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below. FIG. 1 is a plan view schematically showing a configuration of a coating and developing system 1 on which a substrate coating apparatus according to the present invention is mounted, FIG. 2 is a front view of the coating and developing system 1, and FIG. 1 is a rear view of the coating and developing system 1. FIG.

As shown in FIG. 1, for example, the coating and developing system 1 carries 25 wafers W into and out of the coating and developing system 1 from the outside in units of cassettes and carries wafers W into and out of the cassette C. A cassette station 2 for unloading, a processing station 3 in which various processing apparatuses for performing predetermined processing in a single-sheet type in a coating and developing processing step are arranged in multiple stages, and provided adjacent to the processing station 3. An interface unit 4 for transferring a wafer W to and from an exposure apparatus (not shown) is integrally connected.

In the cassette station 2, a plurality of cassettes C can be mounted in a row in the X direction (up and down direction in FIG. 1) at predetermined positions on a cassette mounting table 5 serving as a mounting portion. Then, the cassette arrangement direction (X direction) and the wafer arrangement direction (Z
(A vertical direction) is provided movably along a transfer path 8 so that each cassette C can be selectively accessed.

The wafer carrier 7 has an alignment function for positioning the wafer W. As will be described later, the wafer carrier 7 is configured to be able to access the extension device 32 belonging to the third processing device group G3 on the processing station 3 side.

In the processing station 3, a main transfer unit 13 is provided at the center thereof, and various processing units are arranged in multiple stages around the main transfer unit 13 to constitute a processing unit group. In the coating and developing system 1,
Four processing unit groups G1, G2, G3, and G4 are disposed. The first and second processing unit groups G1 and G2 are disposed on the front side of the coating and developing processing system 1, and the third processing unit group G3 is disposed. Is disposed adjacent to the cassette station 2, and the fourth processing unit group G4 is disposed adjacent to the interface unit 4. Further, a fifth processing unit group G5 indicated by a broken line as an option can be separately arranged on the back side. The main transfer device 13 includes these processing device groups G1, G2, G3, G4, G5.
The wafer W can be loaded and unloaded to and from various processing apparatuses described below. Note that the number and arrangement of the processing apparatus groups differ depending on the type of processing performed on the wafer W, and the number of processing apparatus groups can be arbitrarily selected as long as it is one or more.

In the first processing apparatus group G1, for example, as shown in FIG. 2, a resist coating apparatus 17 as a coating apparatus according to the present embodiment and a developing processing apparatus 18 for developing a wafer W after exposure are provided. They are arranged in two stages from the bottom. Similarly, in the case of the processing apparatus group G2, the resist coating apparatus 1
9 and a development processing device 20 are stacked in two stages from the bottom.

In the third processing unit group G3, for example, as shown in FIG.
0, an adhesion device 31 for improving the fixability between the resist solution and the wafer W, an extension device 32 for transferring the wafer W, prebaking devices 33 and 34 for evaporating the solvent in the resist solution, and a developing process For example, six post-baking devices 35 for performing a subsequent heat treatment are stacked in order from the bottom.

In the fourth processing unit group G4, for example, a cooling device 40, an extension cooling device 41 for naturally cooling the mounted wafer W, an extension device 42, a cooling device 43, and post-exposure baking for performing a heat treatment after exposure. Devices 44 and 45 and a post-baking device 46 for performing a heat treatment after the development process are stacked in, for example, seven stages from the bottom.

A wafer carrier 50 is provided at the center of the interface section 4. The wafer transfer body 50 is configured to freely move in the X direction (vertical direction in FIG. 1), the Z direction (vertical direction), and rotate in the θ direction (rotation direction about the Z axis). , The extension cooling device 41, the extension device 42, the peripheral exposure device 51, and the exposure device (not shown) belonging to the fourth processing device group G4, and
Can be transported.

Next, the configuration of the above-described resist coating apparatus 17 will be described. FIG. 4 is an explanatory view of a longitudinal section showing an outline of the configuration of the resist coating apparatus 17, and FIG. 5 is an explanatory view of a transverse section showing an outline of the configuration of the resist coating apparatus 17.

As shown in FIGS. 4 and 5, a substantially box-shaped outer container 61 having an upper surface opened in the X direction (the vertical direction in FIG. 5) is provided in the casing 60 of the resist coating device 17. ing. The outer container 61 has a transfer section L for loading / unloading the wafer W and a processing section R for coating the wafer W. The processing section R is located on the positive side in the X direction. L is located on the negative side in the X direction.

In the outer container 61, an inner container 62 for accommodating the wafer W is provided in a substantially box shape having an open upper surface. At the center of the inner container 62, there is provided a holding portion 63 for sucking and holding the wafer W. A drive unit 64 including a motor, a cylinder, and the like is provided below the holding unit 63, and the holding unit 63 can be moved up and down. As a result, the wafer W is moved up and down when the wafer W is loaded, so that the transfer of the wafer W from the main transfer device 13 can be suitably performed. The holding unit 63 is rotatable by a driving unit 64, and rotates the wafer W held by the holding unit 63.
Alignment can be performed. For example, an ultrasonic vibrator 65 is attached to the holding unit 63.
By vibrating 3 at a high frequency, the resist liquid applied on wafer W can be leveled by vibration. A solvent tank 66 for storing the solvent of the resist solution is provided at the inner bottom of the inner container 62. Thus, the interior of the inner container 62 can be maintained in the solvent atmosphere.

The inner bottom of the outer container 61 has a longitudinal direction (X
Direction), a rail 68 is provided.
2 is provided movably on the rail 68.
The rail 68 is provided with an inner container moving mechanism 69 that enables the inner container 62 to move. The inner container moving mechanism 69
An inner container driving unit 70 including a motor for moving the inner container 62 by electric power, a power supply 71 for supplying electric power to the inner container driving unit 70, and an inner container control unit 72 for controlling the inner container driving unit 70 by adjusting the power supply. And is constituted by. Thus, the inner container 62 can move between the transport unit L and the processing unit R along the rail 68. In addition, since the inner container 62 can move a predetermined distance at a predetermined timing at the time of coating, the holding portion 63 in the inner container 62 can be intermittently horizontally moved in the positive X direction as one direction. Become.

As shown in FIG. 5, for example, the X
The cleaning section (not shown) located outside on the negative side
A mask member 73 that covers the wafer W during coating and limits the coating range of the wafer W is on standby. Mask member 73
Has an opening 73a at the center corresponding to the application range.

The mask member 73 is configured to be movable above the wafer W in the inner container 62 by a transfer device (not shown). A mask support member 74 for supporting the mask member 73 above the wafer W is provided on the inner side wall of the inner container 62. With this configuration, the mask member 73 waiting in the cleaning unit (not shown) is transferred into the inner container 62 after the wafer W is held by the holding unit 63, and the mask member 73 is
Can be placed on the mask support member 74 above the wafer W. As a result, the resist liquid discharged from above by a discharge nozzle 85 serving as a coating liquid discharge section described later is applied only to a predetermined range of the wafer W, and the resist liquid discharged outside the range is blocked by the mask member 73. ， Can be collected.

As shown in FIG. 5, a flat lid 75 for covering the upper surface of the wafer W at the time of coating,
76 are provided. The lids 75 and 76 are formed in a square shape when viewed from a plane so as to match the opening shape of the outer container 61. The lid 75 is on the positive side in the X direction, and the lid 76 is
They are arranged side by side in the negative X direction. Lid 75 and lid 7
6, a gap d is provided, and a discharge nozzle 85 described later reciprocates in the gap d in the Y direction so that the resist liquid can be discharged to the wafer W below. Further, the lids 75 and 76 are provided so that there is substantially no gap between the lid 75 and the upper end of the inner container 62. When the inner container 62 is positioned below the lids 75 and 76, the inside of the inner container 62 is moved to a predetermined position. The atmosphere can be maintained. In this embodiment, the lid of claim 1 corresponds to the lid 75.

The lid 75 is supported by support members 77 and 78 provided on the inner side wall of the outer container 61. The support member 77 is arranged on the negative side of the lid 75 in the X direction, and the support member 78 is arranged on the positive side of the lid 75 in the X direction.

The lid 75 is, as shown in FIG.
It is configured to be able to move up and down by 0. Lid lifting mechanism 80
Has an elevating drive unit 81 including a cylinder for elevating and lowering the support member 77, and a control unit 82 for controlling the operation of the elevating drive unit 81. The lifting / lowering drive unit 81 supports the lower part of the support member 77 and can move the support member 77 in the vertical direction. Thus, the support member 77 can be raised by a predetermined distance, and the lid 75 can be inclined such that the negative side in the X direction is higher.

The above-described discharge nozzle 85 is provided so as to be located in the gap d. The discharge nozzle 85 is provided in the outer container 61.
The nozzle moving mechanism 86 provided on the lid 76
It is configured to be movable in the direction.

The nozzle moving mechanism 86 is covered by a case 86a as shown in FIG.
Inside, a slider 87 for holding and sliding the discharge nozzle 85 is provided. The slider 87 is Y
It is provided fixed to a part of the drive belt 88 extending in the direction. The driving belt 88 is hung between a driving pulley 89 and a driven pulley 90 provided on both sides of the outer container 61 on the Y direction side. The drive pulley 89 is rotated forward / reversely by a rotation drive motor 91. With this configuration, the driving pulley 89 is rotated by the rotation driving motor 91, the driving belt 88 moves, and the slider 87
The discharge nozzle 85 can reciprocate in the gap d by sliding in the direction.

The drive belt 88 on the side that does not hold the discharge nozzle 85 is provided with a balance weight 92 that is balanced in weight with the slider 87, and minimizes the shaking that occurs when the slider 87 moves. It can be suppressed.

With the above configuration, the resist liquid is discharged onto the wafer W while the discharge nozzle 85 above the wafer W is reciprocated in the Y direction, and the inner container 62 is intermittently moved in the positive X direction. The resist liquid can be applied to the surface of the wafer W in a so-called one-stroke manner.

Next, the operation of the resist coating apparatus 17 configured as described above will be described together with the photolithography process performed in the coating and developing system 1.

First, the wafer carrier 7 takes out one unprocessed wafer W from the cassette C and carries it to the extension device 32 belonging to the third processing device group G3. Next, the wafer W is carried into the adhesion device 31 by the main transfer device 13, and the wafer W is coated with, for example, HMDS for improving the adhesion of the resist solution. Next, the wafer W is
It is conveyed to the cooling device 30 and cooled to a predetermined temperature. Then, the wafer W cooled to a predetermined temperature is transferred by the main transfer device 13 to, for example, a resist coating device 17.

The wafer W to which the resist solution has been applied by the resist coating device 17 is transferred to the pre-baking device 33 and heated, and then transferred to the extension cooling device 41 to be cooled. Next, the wafer W is taken out from the extension cooling device 41 by the wafer carrier 50, and thereafter, the peripheral exposure device 51
Is transferred to an exposure apparatus (not shown) through which the predetermined pattern is exposed on the wafer W. The wafer W that has been subjected to the exposure processing is transferred by the wafer transfer body 50 to the extension device 42, then transferred by the main transfer device 13 to the post-exposure baking device 44, and after being subjected to a heating process, transferred to the cooling device 43. And
It is cooled.

The wafer W after the cooling process is transferred to the developing device 18 by the main transfer device 13, where the developing process is performed, and then transferred to the post-baking device 46 and the cooling device 30 sequentially. Is performed. Thereafter, the wafer W is returned to the cassette C via the extension device 32, and a series of coating and developing processes is completed.

Next, the operation of the above-described resist coating device 17 will be described in detail. First, when the wafer W is transferred to the resist coating device 17, the inner container 62 is on standby at the transfer unit L on the negative side in the X direction. Then, the wafer W for which the previous process has been completed is transferred to the inner container 6 by the main transfer device 13.
Holding unit 63 which has been transported into
Passed to. Wafer W delivered to holding unit 63
Is sucked and held by the holding unit 63, and is lowered to a predetermined height by the driving unit 64. At this time, for example, when the wafer W is moved to the processing section R side, the lid 75,
76 so as to be about 4 mm.

Thereafter, a notch or orientation flat of the wafer W is detected by an alignment mechanism (not shown), and based on the detection, the holding section 63 is rotated to position the wafer W at a predetermined position. Next, the mask member 73 waiting in the cleaning unit (not shown) is removed from the outer container 61 by the inner container 6.
2 and is placed on the mask support member 74.
At this time, the inner container 62 is covered with the mask member 73, and the solvent atmosphere in the inner container 62 is maintained by the mask member 73. Next, as shown in FIG. 7, the inner container 62 is moved in the positive X direction by the inner container moving mechanism 69, and the end of the wafer W on the positive X direction side is discharged.
5 is stopped below.

Next, the discharge nozzle 85 is driven by the nozzle driving mechanism 8.
6, the wafer W is moved to a start position S where coating is started, that is, a position outside the wafer W on the negative side in the Y direction as shown in FIG. At this time, as shown in FIG. 9, the support member 77 located on the discharge nozzle 85 side of the lid 75 is raised by the elevation drive unit 81, and the lid 75 is inclined accordingly, and the lid 75 on the discharge nozzle 85 side is The gap with the wafer W increases.

Next, the application of the resist liquid in a so-called one-stroke manner is started. The resist coating process at this time will be described with reference to FIG.
Discharges a linear resist solution onto the surface of the wafer W while moving at a predetermined speed from the start position S in the positive Y direction. Then, the discharge nozzle 85 advances to the outside of the wafer W on the positive side in the Y direction and temporarily stops on the mask member 73. Also at this time, the resist liquid continues to be discharged, and the resist liquid discharged to a place other than the wafer W is received by the mask member 73 and collected.

Next, the inner container 62 is shifted by a predetermined distance in the positive X direction by the inner container moving mechanism 69, and the wafer W is also moved by X.
The direction is shifted in the positive direction. At this time, with the movement of the wafer W, an airflow directed in the positive X direction is formed in the gap between the wafer W and the lid 75, but the gap between the wafer W and the lid 75 is, for example, 4 mm or more. Discharge nozzle 85
Since the side gap is wide, the influence of the air flow is minimized.

Thereafter, the discharge nozzle 85 is turned back,
Subsequently, while applying the resist solution, the wafer W moves in the negative direction of the Y direction, advances to the outside of the wafer W, and stops. Then, the wafer W is displaced by a predetermined distance in the positive direction of the X direction, and the discharge nozzle 85 again returns to the positive direction of the Y direction to discharge the resist liquid onto the wafer W.

By repeating these steps, the discharge nozzle 85
However, when it reaches the END position E shown in FIG. 8, the discharge of the resist liquid is stopped, and the resist coating is completed. As a result, the resist liquid is applied to the wafer W in a substantially rectangular wave shape, and the resist liquid is applied to the entire surface of the wafer W.

Next, the wafer W is vibrated by the ultrasonic vibrator 65 attached to the holder 63, and the resist liquid on the wafer W is leveled and flattened.

Thereafter, the inner container 62 is moved to the transport section L side, and the mask member 73 is carried out of the outer container 61. Then, the wafer W is transferred from the holding section 63 of the inner container 62 to the main transfer device 13, the wafer W is unloaded from the resist coating device 17, and a series of processes in the resist coating device 17 is completed.

According to the experiment of the inventor, the gap between the wafer W and the lid 75 is set to 1 mm as shown in FIG.
It has been confirmed that the thickness of the resist liquid applied to the wafer W becomes more uniform when the gap is increased to 4 mm (polygonal line a) than when the gap is increased to 4 mm. That is, the wafer W and the lid 75
Is set to 4 mm or more, the resist liquid applied to the wafer W is not affected by the airflow generated in the gap, and the flatness of the resist liquid is ensured. In the above embodiment, since the gap between the wafer W and the lid 75 is set to 4 mm or more, the influence of the air flow in the gap generated when the wafer W moves in the positive X direction is suppressed, and the resist solution Flatness is ensured.

The resist liquid immediately after application has the lowest viscosity because the solvent is not volatilized, and is susceptible to airflow and the like.
In the above-described embodiment, the discharge nozzle 85 side of the lid 75 is raised and inclined by the lid lifting / lowering mechanism 80. Therefore, when the wafer W immediately after application moves in the X direction and firstly faces the lid 75, the lid 75 The gap between the air and the air is the largest, and the effect of airflow is minimized. Further, since the lid 75 on the positive side in the X direction that does not significantly affect the resist liquid on the wafer W is lowered, the gap with the wafer W is narrowed, and the evaporation of the solvent from the resist liquid is suppressed.

The inclination of the lid 75 can be adjusted by the lid lifting / lowering mechanism 80, so that the width of the gap between the lid 75 on the discharge nozzle 85 side and the wafer W can be adjusted. Thereby, the gap can be adjusted so as to suppress the influence of the air flow while suppressing the evaporation of the solvent. Further, the gap can be appropriately changed according to the type of the resist solution, the size of the wafer W, and the like.

In the above embodiment, the positive side in the X direction of the lid 75 is supported by the support member 78.
As shown in FIG. 1, the hinge member 100 may be attached to the end of the lid 75 on the positive side in the X direction. As a result, the lid 75 can be rotated around the end of the lid 75, and the tilting operation of the lid 75 is suitably performed.

When tilting the lid 75,
The cover 75 may be provided diagonally in advance.
As shown in FIG. 5, a lid 105 having a shape with an inclined lower surface may be used.

In the above embodiment, the lid 75 is inclined such that the side of the discharge nozzle 85 of the lid 75 is higher.
5 may be inclined so that the side of the ejection nozzle 85 becomes lower. Such a case will be described as a second embodiment.
For example, as shown in FIG. 13, similarly to the first embodiment, the flat lid 1 is located on the positive side in the X direction from the discharge nozzle 110.
11 is provided. The lid 111 is provided so that a gap between the wafer W and the wafer W becomes 4 mm when the wafer W moves below the lid 111. The lid 111 is supported by support members 112 and 113. The support member 112 that supports the negative side of the lid 111 in the X direction is provided with a lid lifting mechanism 114 that lowers the support member 112. The lid lifting / lowering mechanism 114 includes a lifting / lowering driving unit 115 that supports the supporting member 112 and can move the supporting member 112 up and down, and a control unit 116 that controls the lifting / lowering driving unit 115. The configuration of the other parts is
This is the same as the first embodiment, and the description is omitted.

In the resist liquid coating process, the support member 112 is moved to the lid elevating mechanism 114 before starting the coating.
And the discharge nozzle 11 of the lid 111
The lid 111 is inclined so that the 0 side becomes lower. At this time, when the wafer W moves below the lid 111,
Is set to about 1 mm on the ejection nozzle 110 side. Thereafter, a resist liquid is applied to the wafer W, and when the wafer W moves in the positive direction in the X direction, the wafer W is positioned below the lid 111, and a gap of 4 mm is formed between the wafer W and the lid 111. Then, when the wafer W moves intermittently in the positive X direction, an airflow having a velocity gradient is formed in the gap, and the velocity gradient of the airflow causes
Shear stress acts on the resist solution surface. Then, the resist liquid immediately after application is flattened by the shear stress.

As described above, according to the second embodiment,
The gap between the wafer W and the lid 111 is positively narrowed, and the resist liquid on the wafer W is leveled by the shear stress based on the airflow in the gap, and the flatness of the resist liquid can be secured.

In the above embodiment, the lifting drive for raising and lowering the lid is provided only on the support member on the discharge nozzle side, but may be provided on the support member on the positive X direction side. For example, as shown in FIG. 14, the lid elevating mechanism 80 includes an elevating drive unit 120 that supports and vertically moves the support member 78, and a control unit 121 that controls the elevating drive unit 120. For example, before the application, the support members 77 and the support members 78 are raised by a predetermined distance, and the lid 75 is inclined such that the ejection nozzle 85 side is higher. Thus, similarly to the first embodiment, the airflow formed between the wafer W and the lid 75 is controlled, and the flatness of the resist solution is ensured.

In such a case, the height of the entire cover 75 can be adjusted by moving the support member 77 and the support member 78 up and down by a predetermined distance. For example, in the first embodiment, the gap between the support member 78 and the wafer W is set to 4 mm. However, the flatness of the resist solution and the volatilization amount of the solvent may be compared to be 4 mm or more. 4mm
The following may be used. This makes it possible to provide a more appropriate gap between the wafer W and the lid 75. The timing of changing the height of the entire lid 75 may be during the application of the resist liquid. During coating, the lid 75 is inclined and the wafer W is moved, so that the optimum gap is constantly changing. By changing the gap during coating, the air flow in the gap is more strictly controlled. Control the
Disturbance of the resist solution can be minimized. In the case where the above-mentioned lid is moved up and down at two places, the present invention is also applied to the second embodiment.

Although the lid described in the above embodiment has a flat plate shape, the lid 125 may be curved convexly downward as shown in FIG. In such a case, the airflow generated between the wafer W and the lid 125 flows smoothly, and a stable airflow is formed. Thereby, the wafer W is generated by the air flow.
Disturbance of the upper resist solution is suppressed, and the flatness of the resist solution is ensured. The lid 125 may have an upwardly convex curved shape.

Next, the cover 75 is moved in the X direction,
May be provided. Hereinafter, such a case will be described as a third embodiment.

The resist coating apparatus 130 according to the third embodiment is provided with a rail 132 extending in the X direction on the inner wall of the outer container 131 on the processing section R side, as shown in FIGS. 16 and 17, for example. A flat lid 133 is provided so as to be movable along the rail 132. On the rail 132
A lid driving unit 134 provided with a motor and the like for moving the lid 133 along the rail 132 is provided.
The movement of No. 4 is controlled by the inner container control unit 72 which controls the movement of the inner container 62. The inner container control unit 72 can move the inner container 62 and the lid 133 in synchronization with each other, or can move each of them independently. As described above, the lid moving device includes, for example, the rail 132 and the lid driving unit 13.
4 and an inner container control unit 72. The configuration of other parts is the same as that of the above-described embodiment, and the description is omitted.

Next, the operation of the resist coating apparatus 130 according to the third embodiment will be described. The wafer W carried into the resist coating apparatus 130 is held by the holding section 63 in the inner container 62, Is moved to a position where the application is started. Then, when the application of the resist liquid is started, first, the discharge nozzle 85 moves from the start position S in the positive Y direction, and discharges the resist liquid onto the wafer W. When the discharge nozzle 85 reaches the outside of the wafer W on the negative side in the Y direction, it is temporarily stopped there.

Then, the inner container 62 moves by a predetermined distance in the X direction positive direction, and the coating position of the wafer W is shifted. At this time, as shown in FIG. 18, the lid 133 is moved by the same distance in the positive direction of the X direction in synchronization with the inner container 62 by the inner container controller 72. Subsequently, the discharge nozzle 85 moves to the negative side in the Y direction, and discharges the resist liquid onto the wafer W.
At this time, as shown in FIG. 19, the lid 133 is returned to the original position slowly, for example, at a lower speed than when the lid 133 is moved in the positive X direction.

When the discharge nozzle 85 reaches the outside of the wafer W, it is stopped, and the inner container 62 is moved and shifted by a predetermined distance in the positive X direction. At this time, the lid 133 also moves in the positive direction in the X direction in synchronization with the wafer W as in the previous case. Then, when the discharge nozzle 85 moves in the positive Y direction again, the lid 133 is returned to the original position.

As described above, when the inner container 62 shifts in the positive X direction, the lid 133 is similarly moved in the positive X direction, and then the discharge nozzle 85 moves in the Y direction to discharge the resist liquid. The lid 133 is returned to the original position. By doing so, when the wafer W moves in the positive direction in the X direction, the velocity gradient of the airflow formed between the wafer W and the lid 133 is reduced, and the shear stress acting on the resist liquid surface can be reduced. . Further, since the lid 133 is slowly returned to the original position while the discharge nozzle 85 is moving in the Y direction, the gap d is widened and the solvent of the resist liquid from the wafer W can be suppressed from evaporating. Also, since the return is performed at a low speed, the movement at this time prevents an airflow having a large velocity gradient from being formed, thereby preventing the resist liquid from being adversely affected.

By the way, the coating liquid such as the resist liquid applied on the wafer W tends to move as the film thickness increases. The closer the lid 75 is to the surface of the wafer W, the more the evaporation of the liquid on the wafer W can be suppressed, and the occurrence of turbulence can be suppressed. Therefore, it is preferable that the distance between the lid 75 and the surface of the wafer W increases as the film thickness increases, and the distance between the lid 75 and the surface of the wafer W decreases as the film thickness decreases.

Therefore, the degree to which the support member 77 is moved up and down based on the thickness of the resist film applied to the surface of the wafer W in advance is input to the control unit 82 which controls the operation of the elevation drive unit 81. By doing so, it is possible to suitably control the degree of separation of the lid 75 from the surface of the wafer W based on the thickness of the film.

In this case, for example, as shown in FIG.
An input device 140 for inputting a film thickness to the control unit 82 is connected to the control unit 82. On the other hand, the control unit 82 has a film thickness and a preferable approach / separation degree of the lid to the wafer W corresponding to the film thickness in advance. Is provided. By adopting such a configuration, based on the film thickness information input from the input device 140, the control unit 82 determines the optimal approach / separation degree of the lid 75 corresponding to the film thickness registered in the storage unit. And outputs it to the elevation drive unit 81. Based on this, the lifting drive unit 81 moves the lid 75 closer and further away. This is also valid for the examples shown in FIGS.

Evaporation from a coating film such as a resist film applied on the wafer W is greatly affected by the temperature. In this regard, for example, as shown in FIG. 21, the temperature adjusting unit 141 may be housed inside the lid 75 to control the temperature of the lid 75, particularly, the temperature of the lower surface of the lid 75. The temperature adjustment unit 141 itself can employ a well-known technique such as a flow path through which cooling water flows, a Peltier element, and a heat pipe.

The range of temperature control is, for example, 10 ° C. to 2 ° C.
A range of 3 ° C. is preferred. If the temperature is lower than 10 ° C., the surface of the lid 75 may be condensed. If the temperature is higher than 23 ° C., evaporation from the applied liquid may be accelerated. By controlling the temperature of the lid 75 in such a range, evaporation from the coating film on the surface of the wafer W is suppressed, and as a result, generation of airflow can be suppressed.
As the material of the lid 75, a material having good heat conductivity such as stainless steel or aluminum is suitable, and resin or quartz glass is not very suitable. Note that the temperature adjusting unit 142 may be housed in the lid 76 covering the upper part of the wafer W in the same manner.

Although the above embodiment has been applied to a coating apparatus for applying a resist solution onto a wafer, the present invention relates to a coating apparatus for applying another coating liquid for forming an insulating film or the like. For example, the present invention can be applied to a coating apparatus for forming a SOD, SOG film, or the like. Although the embodiments described above have been applied to a coating apparatus in a photolithography step of a semiconductor wafer device manufacturing process, the present invention is also applied to a coating apparatus for a substrate other than a semiconductor wafer, for example, an LCD substrate. it can.

[0080]

According to the present invention, the flatness of the coating solution can be ensured by controlling the airflow generated between the substrate and the lid, so that a uniform coating film having a predetermined thickness can be formed on the substrate. Thus, the yield is improved.

[Brief description of the drawings]

FIG. 1 is a plan view schematically showing a configuration of a coating and developing system equipped with a resist coating apparatus according to an embodiment.

FIG. 2 is a front view of the coating and developing system of FIG.

FIG. 3 is a rear view of the coating and developing system of FIG. 1;

FIG. 4 is an explanatory view of a longitudinal section showing a configuration of a resist coating apparatus.

FIG. 5 is an explanatory view in a cross section showing a configuration of a resist coating apparatus.

FIG. 6 is a perspective view illustrating a configuration of a nozzle moving mechanism.

FIG. 7 is an explanatory cross-sectional view showing the configuration of the resist coating apparatus when the inner container has moved to the processing section R side.

FIG. 8 is an explanatory diagram showing a coating route of a resist solution.

FIG. 9 is an explanatory diagram of an outer container schematically showing a state where a lid is raised from a side.

FIG. 10 is a graph showing an experimental result of measuring a film thickness of a resist solution on a wafer while changing a gap between the wafer and a lid.

FIG. 11 is a side view schematically showing the inside of the outer container when the hinge member is attached to the lid.

FIG. 12 is a side view schematically showing the inside of an outer container when a lid having another shape is used.

FIG. 13 is an explanatory view schematically showing a configuration inside an outer container in the second embodiment.

FIG. 14 is an explanatory diagram schematically showing the inside of the outer container when a lifting drive unit is attached to two places of the lid, from the side.

FIG. 15 is an explanatory diagram showing an example of a configuration inside an outer container when a lid is formed into a curved shape.

FIG. 16 is an explanatory view of a longitudinal section showing a configuration of a resist coating apparatus according to a third embodiment.

FIG. 17 is an explanatory view of a cross section of the resist coating apparatus of FIG. 16;

FIG. 18 is a schematic plan view of an outer container illustrating an operation of the resist coating apparatus according to the third embodiment.

FIG. 19 is a schematic plan view of an outer container illustrating an operation of the resist coating device according to the third embodiment.

FIG. 20 is an explanatory diagram of an example provided with a film thickness input device for a control unit.

FIG. 21 is an explanatory diagram of a cover having a temperature control unit inside.

[Explanation of symbols]

 Reference Signs List 1 coating / developing processing system 17 resist coating device 61 outer container 62 inner container 63 holding unit 72 inner container moving mechanism 75 lid 76 lid 77 support member 78 support member 81 elevating drive unit 85 discharge nozzle W wafer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuki Morikawa 5-3-6 Akasaka, Minato-ku, Tokyo TBS Release Center Inside Tokyo Electron Limited (72) Inventor Kazuhiro Takeshita 5-3-1 Akasaka, Minato-ku, Tokyo No. 6 TBS Broadcasting Center Tokyo Electron Limited (72) Inventor Yoshiyuki Kawabuchi 5-6 Akasaka, Minato-ku, Tokyo TBS Broadcasting Center Tokyo Electron Limited F-term (reference) 2H025 AA18 AB14 AB16 AB17 EA04 4D075 AC06 AC08 AC88 AC96 CA47 DA06 DB13 DB14 DC22 EA07 EA45 4F041 AA02 AA06 AB01 BA22 BA34 5F046 CD01 CD05 JA02 JA20 JA24 JA27

Claims (14)

[Claims] An application apparatus for applying an application liquid onto a substrate, wherein the application apparatus reciprocates on the substrate in a predetermined direction and discharges the application liquid onto the substrate; A holding portion that can move horizontally in one direction perpendicular to the predetermined direction, and a lid that covers an upper surface of the substrate when the substrate moves in one direction from the application liquid ejection portion when viewed from a plane. And a lower surface of the lid is inclined so that the side of the coating liquid discharge section is higher. 2. A coating apparatus for coating a substrate with a coating liquid, wherein the coating apparatus discharges a coating liquid onto the substrate by reciprocating on the substrate in a predetermined direction, and holds the substrate. A holding portion that can move horizontally in one direction perpendicular to the predetermined direction, and a lid that covers an upper surface of the substrate when the substrate moves in one direction from the application liquid ejection portion when viewed from above. And a lower surface of the lid is inclined so that the side of the coating liquid discharge section is lower. 3. The substrate coating apparatus according to claim 1, wherein the lower surface of the lid is curved. 4. The substrate coating apparatus according to claim 1, wherein the lid has a flat plate shape, and has a lid elevating mechanism for raising and lowering a part of the lid. . 5. The apparatus for coating a substrate according to claim 4, wherein the lid lifting mechanism is configured to raise and lower the vicinity of both ends of the lid in the one direction. 6. The substrate coating apparatus according to claim 4, further comprising a control device for controlling a degree of elevation of the lid elevating mechanism based on a film thickness of the application liquid on the substrate. . 7. A step of applying a coating liquid onto a substrate while the coating liquid discharge section moves in a predetermined direction on the substrate, and, when the coating liquid discharge section reaches the outside of the substrate, the substrate is removed. The step of moving a predetermined distance in one direction perpendicular to the predetermined direction and the step of applying the coating liquid on the substrate while the coating liquid discharger moves on the substrate in the opposite direction to the predetermined direction are repeatedly performed. A coating method for a substrate in which a coating liquid is applied to the entire surface of the substrate, wherein, when the substrate is moved in the one direction, a lid that covers an upper surface of the substrate is moved in the same one direction as the substrate; Moving the lid to its original position before moving the lid when the coating liquid ejection unit moves in the opposite direction to the predetermined direction to apply the coating liquid to the substrate. Substrate coating method. 8. The substrate according to claim 7, wherein a speed at which the lid moves to the original position is lower than a speed at which the lid moves a predetermined distance in the one direction. Coating method. 9. A coating apparatus for coating a substrate with a coating liquid, wherein the coating apparatus discharges a coating liquid onto the substrate by reciprocating on the substrate in a predetermined direction, and holds the substrate. A holding portion that can move horizontally in one direction perpendicular to the predetermined direction, a lid that covers an upper surface of the substrate, and a lid moving device that moves the lid in a direction perpendicular to the predetermined direction. Substrate coating device. 10. The substrate coating apparatus according to claim 1, wherein the temperature of the lid is adjustable. 11. The apparatus of claim 10, wherein the temperature of the lid is adjusted in a range of 10 ° C. to 23 ° C. 12. The substrate coating apparatus according to claim 10, wherein a cooling water flow path is formed in the lid. 13. The substrate coating apparatus according to claim 10, wherein a Peltier element is housed in the lid. 14. The substrate coating apparatus according to claim 10, wherein a heat pipe device is housed in the lid.