JP2003257840A - Device and method for removing applied film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for removing coated film by which the removing cost of applied films can be reduced by reducing the amount to be used of a liquid chemical and, in addition, the applied film formed on a peripheral edge section of a substrate can be removed in a shorter time for processing by increasing a coated film dissolving power of the liquid chemical. <P>SOLUTION: The device for removing applied film is provided with a driving/ holding means 70 which rotates and inclines a substrate W having the coated film on its surface by holding the substrate W, and a liquid chemical storing means 25 which is provided in the vicinity of the means 70 and has an opening 25a to which part of the peripheral edge of the substrate W is faced when the substrate W is in an inclined and rotated state. In the storing means 25, the liquid chemical A used for dissolving the peripheral edge of the coated film is stored. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating film removing apparatus and a coating film removing method used for removing an unnecessary coating film on a peripheral portion of a semiconductor wafer, for example.

[0002]

2. Description of the Related Art As a method for forming a dielectric film (coating film) such as an interlayer insulating film in a semiconductor device manufacturing process, SOD (spin on dielectric) is used.
A coating film forming method is known in which a system is used to apply a coating liquid to a semiconductor wafer (hereinafter referred to as “wafer”) to form a coating film, and then a physical treatment such as heating is performed. Here, as a method for forming the coating film, the coating liquid is generally dropped on the substantially central portion of the wafer which is stopped or rotated, and then the wafer is rotated at a predetermined number of rotations to apply the coating liquid to the entire surface of the wafer. To diffuse into the surface (spin coating method)
Is used.

In such a coating film forming method, since the solvent in the coating liquid evaporates in the process in which the coating liquid diffuses from the central portion of the wafer toward the peripheral portion, the viscosity of the coating liquid is in the diffusion direction. However, the film thickness at the peripheral portion of the wafer is larger than that at the central portion. Further, the coating liquid adheres not only to the upper surface of the wafer but also to the end surface of the wafer. If such a phenomenon occurs, a transport error may occur or particles may be generated during the transport process. Therefore, the coating film on the peripheral portion of the wafer is removed (EBR process) by supplying a chemical liquid (solvent) such as thinner from a nozzle.

[0004]

However, in the method of removing the coating film described above, since the chemical solution is discharged onto the peripheral portion of the wafer to be processed, a large amount of chemical solution is used in the entire removal process. However, there is a problem that the cost increases. In addition, since the coating film is removed by ejecting the chemical solution from the needle-shaped nozzle toward the peripheral edge of the rotating wafer, the chemical solution diffuses to the peripheral edge of the wafer, and the dissolving power of the coating film decreases. There was a problem.

The present invention has been made in order to solve such a technical problem, and it is possible to reduce the amount of the chemical solution used and to reduce the cost, and to improve the dissolving power of the coating film. An object of the present invention is to provide a coating film removing apparatus and a coating film removing method capable of removing the coating film on the peripheral portion of the substrate in a shorter processing time.

[0006]

A coating film removing apparatus according to the present invention made to achieve the above-mentioned object is a drive / holding means for holding and rotating a substrate having a coating film formed on its surface. And a chemical solution storage means provided in the vicinity of the drive / holding means and having an opening portion such that a part of the peripheral edge thereof faces when the substrate is tilted / rotated. It is characterized in that a chemical solution for dissolving the peripheral portion of the coating film is stored.

With this structure, the peripheral portion of the coating film is removed by immersing a part of the peripheral portion in the chemical liquid in the chemical liquid storage means while rotating the substrate. Therefore, unlike the conventional case, it is not necessary to discharge the chemical liquid for each wafer to be processed, so that the amount of the chemical liquid used in the entire removal process can be reduced and the cost can be reduced. Further, since the coating film is removed by immersing the peripheral portion of the substrate in the chemical solution, the dissolving power of the coating film can be further enhanced as compared with the case of the conventional nozzle.

Here, it is preferable that the chemical liquid storage means has a level sensor for detecting the liquid level of the chemical liquid.
With this configuration, the chemical solution is replenished according to the liquid level of the chemical solution detected by the level sensor.

Further, it is preferable that the chemical liquid storage means has a temperature adjusting device for adjusting the temperature of the chemical liquid. Thus, by heating the chemical liquid to a predetermined temperature, the dissolving power of the chemical liquid can be increased. Further, it is desirable that a drying means for drying the peripheral portion of the substrate is provided in the vicinity of the chemical solution storing means, and that the drying means is a gas suction / discharge device or an infrared heating device. With such a configuration, when the coating film is removed, drying of the peripheral portion of the coating film is promoted, and it is possible to prevent the chemical solution from dripping.

Further, it is preferable that the chemical liquid storage means has an ultrasonic vibration device for applying ultrasonic vibration to the chemical liquid. As described above, since ultrasonic vibration is applied to the chemical liquid by the ultrasonic vibration device, the dissolving force can be increased and the coating film can be removed more reliably.

On the other hand, the method for removing a coating film according to the present invention is a method for removing a coating film formed on the surface of a substrate, in which the substrate is immersed in a chemical solution that dissolves the coating film. The coating film is removed by immersing a part of the peripheral edge and rotating the substrate around an axis perpendicular to the surface thereof. According to such a method, the coating film on the peripheral portion of the substrate is removed by immersing a part of the peripheral edge in the chemical liquid in the chemical liquid storage means while rotating the substrate. Therefore, it is possible to reduce the amount of the chemical liquid used and to reduce the cost, and it is possible to more surely increase the dissolving power as compared with the case of the conventional nozzle, and to reliably remove the coating film. it can.

Here, it is desirable to dry at least the peripheral portion of the substrate before immersing the coating film of the substrate in a chemical solution that dissolves it. According to such a method, it is possible to prevent the occurrence of hump (HUMP) and sagging due to the chemical solution and to suppress the deterioration of the film quality.

Further, while a part of the peripheral edge of the substrate is immersed in a chemical solution that dissolves the coating film and the substrate is rotated around an axis perpendicular to the surface of the substrate, It is desirable to dry at least the peripheral portion.
According to such a method, when the substrate comes out of the chemical solution to the outside due to the rotation of the substrate, the chemical solution attached to the substrate is prevented from flowing (dripping).

Furthermore, ultrasonic vibration is applied to the chemical while the peripheral portion of the substrate is partially immersed in a chemical that dissolves the coating film and the substrate is rotated around an axis perpendicular to the surface of the substrate. It is desirable to do. According to such a method, since the substrate is immersed in the chemical solution that has been subjected to ultrasonic vibration, the coating film can be more effectively removed.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION A coating film removing apparatus to which the present invention is applied will be described below with reference to FIGS. 1 and 2. 1 and 2 are a cross-sectional view and a plan view for explaining the configuration of a coating film removing apparatus according to an embodiment of the present invention.
In this embodiment, the case where the substrate to be processed is a wafer will be described.

As shown in FIG. 1, the coating processing unit (S
An annular coater cup (CP) is arranged at the center of (CT) 11, and a wafer drive / holding means 70 is arranged inside this coater cup (CP). The wafer drive / holding means 70 has a spin chuck 71. The spin chuck 71 is configured to hold and hold the wafer W substantially horizontally by vacuum suction, and rotate by a drive motor 72. In addition, the spin chuck 71 is
The drive motor 22 is configured to be tilted together with the tilting plate 24. Also, the coater cup (CP)
A drain 73 is provided at the bottom of the. Then, the unnecessary coating liquid, rinse liquid such as thinner, and the like are discharged.

The drive motor 22 has a unit bottom plate 74.
It is arranged on the upper lift 23. The lift table 23 is connected to a lift drive mechanism (for example, an air cylinder) 76 and a lift guide 77. The drive motor 72 is arranged on the tilt plate 24. A cylindrical cooling jacket (not shown) made of, for example, SUS is attached to the drive motor 72 and the drive motor 22.

On the unit bottom plate 74 (outside the coater cup), the tank 2 as the chemical solution storing means which constitutes the coating film removing device 10 together with the wafer driving / holding means 70.
5 are arranged. In addition, the unit bottom plate 74 is provided with a liquid discharge port (not shown) for discharging the unnecessary chemical liquid A scattered outside the tank 25.

As shown by the chain double-dashed line in FIG. 1, the tank 25 has an opening 25a so that a part of its peripheral edge faces when the wafer W is tilted and held. Then, the chemical liquid A such as thinner is stored in the tank 25, and the peripheral portion of the coating film formed on the surface of the wafer W is dissolved and removed. In addition, the tank 25
Has a level sensor 26 for detecting the liquid level of the chemical liquid A. As a result, depending on the liquid level of the chemical liquid A in the tank 25, the chemical liquid A is supplied from the chemical liquid supply unit 27 to the tank 25.
Done in.

The coating film removing device 10 is additionally provided with an infrared heating device 28 as a drying means located near the tank 25. This accelerates the drying of the peripheral portion of the wafer W, which is discharged from the chemical liquid A to the outside when the coating film is removed, and prevents the chemical liquid from flowing (dripping). Although not shown, the chemical liquid tank 25 is provided with a temperature adjusting device for keeping the chemical liquid at a predetermined temperature. As this temperature adjusting device, a hot water heater can be exemplified. By making the chemical liquid A at a predetermined temperature in this way,
The dissolving power can be increased. Wafers W
It goes without saying that the drying of the peripheral portion after the immersion in the chemical liquid is promoted.

The lower end surface 23a of the elevating table 23 is a unit bottom plate 74 when the processing liquid (coating liquid and solvent) is applied.
It is configured to be in close contact with the upper surface of the. In addition, the wafer W is transferred between the spin chuck 71 and the wafer transfer arm 55.
When the wafer is transferred and the coating film on the peripheral portion of the wafer W is removed, the lifting drive mechanism 76 drives the wafer.
The holding means 70 (both drive motors 22 and 72, spin chuck 71, etc.) is configured to be lifted from the unit bottom plate 74 by lifting it upward.

The tilting plate 24 is rotatably supported by the elevating table 23 via a support shaft 24a. Then, when the coating film on the peripheral portion of the wafer W is removed, the spin chuck 71 is driven by the drive motor 22.
And is configured to tilt together with the drive motor 72.

Further, the coating processing unit 11 is provided with a coating liquid discharge nozzle 81 for discharging a coating liquid such as polyimide resin onto the surface of the wafer W. The coating liquid discharge nozzle 81 is detachably attached to the tip of the first scan arm 82 via a nozzle holder 83.
It is configured to be movable in the Z direction by the Z-axis drive mechanism 97. Further, it is connected to the coating liquid supply unit 95, and the coating liquid is supplied from the coating liquid supply unit 95.

The tip portion of the coating liquid discharge nozzle 81 is a nozzle standby portion 98 shown in FIG.
By being inserted into 8a and being exposed to a solvent atmosphere therein, the coating liquid at the tip of the nozzle is prevented from solidifying or deteriorating. Further, the coating liquid discharge nozzle 81 is composed of a plurality of nozzles, and is used properly according to the type of coating liquid, for example.

The first scan arm 82 is attached to the upper end of a vertical support member 85 that is horizontally movable on the guide rail 84 of the unit bottom plate 74, and is integrated with the vertical support member 85 by a Y-axis drive mechanism 96. It is configured to be movable in the Y direction. The first scan arm 82 can also be moved in the X direction orthogonal to the Y direction by an X axis drive mechanism (not shown) in order to selectively attach the coating liquid discharge nozzle 81 in the nozzle standby portion 98. Is configured.

Further, the coating processing unit (SCT)
A treatment liquid discharge nozzle 81 a and a back rinse nozzle 123 are arranged at 11. The processing liquid discharge nozzle 81a is configured to discharge the solvent onto the wafer W and obtain the wettability of the coating liquid with respect to the wafer W. Further, the back rinse nozzle 123 discharges a rinse liquid such as thinner, and the wafer W held by the spin chuck 71.
Is configured to remove the coating liquid adhering to the back surface of the.

The processing liquid discharge nozzle 81a is detachably attached to the tip of the second scan arm 82a via a nozzle holder 83a, and is configured to be movable in the Z direction by a Z-axis drive mechanism 97. There is. Further, the solvent is supplied from a processing liquid supply unit (not shown). The processing liquid discharge nozzle 81a and the like are not shown in FIG. 1 because they overlap the coating liquid discharge nozzle 81 and the like when viewed from the Y direction.

The operation of the drive system of the coating processing unit (SCT) 11 configured as described above is controlled by the controller 90. That is, the drive motors 22 and 72, the X-axis drive mechanism (not shown), the Y-axis drive mechanism 96, the Z-axis drive mechanism 97, the coating liquid supply unit 95, the processing liquid supply unit, and the chemical liquid supply unit 2
7. The thinner supply unit and the like are drive-controlled by a command from the control unit 90.

Next, a method for removing a coating film using the above coating processing unit will be described with reference to FIGS. FIG. 3 is a cross-sectional view shown for explaining the coating film removing method according to the embodiment of the present invention. In the coating film removing method, since the "raising operation", the "tilting operation (immersion processing)", and the "rotating operation" of the wafer W are sequentially performed,
Each of these operations will be sequentially described.

In carrying out this coating film removing method,
It is assumed that both the coating liquid discharge nozzle 81 and the processing liquid discharge nozzle 81a are arranged outside the coating film forming operation region, and the spin chuck 71 is arranged at the coating film forming operation position (lowermost position). In addition, the wafer W has an insulating film (coating film) formed on its surface and is held by the spin chuck 71 substantially horizontally.

"Climbing Operation" By driving the elevating / lowering drive mechanism 76, the spin chuck 71 at the position shown by the solid line in FIG. 3 (a) is lifted and placed at the position shown by the chain double-dashed line in FIG. 3 (a). . In this case, when the spin chuck 71 moves up, the wafer W in the coater cup (CP) moves upward together with the spin chuck 71 and is placed outside the coater cup (CP).

By rotating the "immersion process" drive motor 22, the spin chuck 71 (tilting plate 24) at the position shown by the solid line in FIG. 4B is rotated counterclockwise (direction of arrow a) of the support shaft 24a. The figure (b)
It is placed at the position indicated by the chain double-dashed line. In this case, when the spin chuck 71 tilts, the wafer W in a substantially horizontal posture tilts 90 ° together with the spin chuck 71. Therefore, a part of the peripheral edge of the wafer W faces the opening 25a of the tank 25,
It is immersed in the chemical solution A in the tank 25.

"Rotation operation" By rotating the drive motor 72, the spin chuck 71 is moved in the direction of arrow m (axis O perpendicular to the surface of the wafer W as shown in FIG. 4C).
Rotate). In this case, when the control unit 90 controls the wafer W to rotate at a predetermined rotation speed (for example, 30 rpm), the entire peripheral portion of the coating film is supplied with the chemical liquid A and removed. In addition, when the wafer W comes out of the chemical solution A due to the rotation of the wafer W, the infrared heating device 2
In order to prevent the chemical liquid adhering to the wafer W from flowing (dripping) by 8, the peripheral portion of the wafer W is dried. By thus immersing the peripheral portion of the wafer W in the chemical liquid A, the coating film can be removed more reliably. After the above process, the spin chuck 71 (tilting plate 24) is attached to the support shaft 24a.
Is rotated (tilted) 90 ° clockwise (in the direction of arrow a) to return to a substantially horizontal state, and the removal of the coating film is completed.

Before removing the coating film (wafer W
It is also desirable to rotate the wafer W, for example, before immersing the wafer W into the wafer W and accelerate the drying of the peripheral portion thereof by an infrared irradiation device or the like. As a result, it is possible to prevent hump and sagging due to the chemical liquid A and prevent deterioration of the film quality.

It is desirable that the tank 25 be provided with an ultrasonic vibration device for applying ultrasonic vibration to the chemical liquid A. Since ultrasonic vibration is applied to the chemical liquid A by the ultrasonic vibration device, the dissolving power of the chemical liquid can be increased,
The coating film can be removed more reliably.

When the above-mentioned removal processing is performed a predetermined number of times (for example, 100 wafers are processed), the tank 25
Replace the drug solution A inside. In this case, the used chemical liquid A can be reused by passing it through a filter (not shown) or the like. Therefore, in the present embodiment, since it is not necessary to discharge the chemical liquid for each wafer that processes the chemical liquid A, it is possible to reduce the usage amount of the chemical liquid A in the entire coating process and to reduce the cost. it can. Further, in the present embodiment, since the coating film is removed by immersing the peripheral portion of the wafer W in the chemical liquid A, the dissolving power can be increased.

In this embodiment, the case where the wafer W is tilted and then rotated has been described. However, the present invention is not limited to this, and the wafer W is tilted while being rotated so that the wafer W is immersed in the chemical solution. You may soak. Further, in the present embodiment, the case where the dipping process is performed by tilting the wafer W by 90 ° has been described, but the tilt angle of the wafer W in the present invention is not particularly limited.

Further, although the case where the infrared heating device 28 is used as the drying means has been described in the present embodiment, the present invention is not limited to this, and the gas suction device (vacuum suction nozzle) and the gas discharge device (supply gas). as,
For example, even if air or nitrogen gas) is used, the same effect as that of the embodiment can be obtained. In this case, the gas suction device and the gas discharge device may be used at the same time, or either one of them may be used.

Besides, in the present embodiment, the case of applying to the removal of the insulating film has been described, but the present invention is not limited to this and is applicable to the removal of, for example, the semiconductor film, the electrode film, and the photoresist film. Is. Further, in the present invention, the processing substrate is not limited to a wafer, and may be, for example, an LCD.
Of course, it may be a substrate or another substrate such as a CD.

[0040]

As is apparent from the above description, according to the coating film removing apparatus and method of the present invention, the amount of the chemical solution used can be reduced, the cost can be reduced, and the dissolving power can be increased. Therefore, the coating film can be reliably removed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view shown for explaining a configuration of a coating film removing apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view shown for explaining the configuration of the coating film removing apparatus according to the embodiment of the present invention.

3A to 3C are cross-sectional views shown for explaining a method of removing a coating film according to an embodiment of the present invention.

[Explanation of symbols]

10 Coating film removing device 11 Coating processing unit (SCT) 22 Drive motor 23 Lifting platform 24 Tilt plate 24a spindle 25 tanks 25a opening 26 level sensor 27 Chemical supply unit 28 Infrared heating device 55 Wafer transfer arm 70 Wafer drive / holding means 71 Spin chuck 72 Drive motor 73 drain 74 unit bottom plate 81 Coating liquid discharge nozzle 81a Treatment liquid discharge nozzle 83,83a nozzle holder A chemical liquid CP coater cup W wafer

Continued front page    F-term (reference) 2H096 AA25 DA04                 4D075 AC65 BB20Z BB27Z DA06                       DB14 DC22 EA07 EA19 EA21                 4F042 AA02 AA07 AB00 EB05 EB09                       EB13 EB18 EB27                 5F046 JA15

Claims (10)

[Claims] 1. A driving / holding means for holding and rotating / tilting a substrate having a coating film formed on its surface, and a peripheral portion of the driving / holding means arranged in the vicinity of the driving / holding means when the substrate is tilted / rotated. A coating solution removing means having an opening partly facing the coating solution, wherein a solution for dissolving the peripheral portion of the coating film is stored in the coating solution removing means. apparatus. 2. The coating film removing apparatus according to claim 1, wherein the chemical liquid storage unit has a level sensor for detecting a liquid level of the chemical liquid. 3. The coating film removing apparatus according to claim 1, wherein the chemical liquid storage unit has a temperature adjusting device for adjusting the temperature of the chemical liquid. 4. The coating film removing apparatus according to claim 1, further comprising a drying means for drying the peripheral portion of the substrate in the vicinity of the chemical solution storage means. . 5. The coating film removing device according to claim 4, wherein the drying means is a gas suction / discharge device or an infrared heating device. 6. The coating film removing apparatus according to claim 1, wherein the chemical liquid storage unit includes an ultrasonic vibration device that applies ultrasonic vibration to the chemical liquid. 7. A coating film removing method for removing a peripheral portion of a coating film formed on a surface of a substrate, wherein the peripheral portion of the substrate is immersed in a chemical solution that dissolves the coating film, and the substrate is removed. A method for removing a coating film, which comprises removing the coating film by rotating it about an axis perpendicular to the surface. 8. The method for removing a coating film according to claim 7, wherein at least a peripheral portion of the substrate is dried before being immersed in a chemical solution for dissolving the coating film on the substrate. 9. A substrate, which has come out of the chemical solution while being immersed in a chemical solution for dissolving the coating film, at a part of the peripheral edge of the substrate and rotating the substrate around an axis perpendicular to the surface thereof. 9. The coating film removing method according to claim 7, wherein at least a peripheral portion is dried. 10. An ultrasonic vibration is applied to the chemical while dipping a part of the peripheral edge of the substrate in a chemical that dissolves the coating film and rotating the substrate around an axis perpendicular to the surface thereof. The coating film removing apparatus according to any one of claims 7 to 9, wherein