JP2688716B2 - Liquid processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a processing apparatus.

(Prior Art) In a semiconductor manufacturing process, surface treatment of a semiconductor wafer (hereinafter, abbreviated as a wafer) includes, for example, a resist coating process and a developing process. In this resist coating processing device,
JP-A-58-171819, JP-A-59-82975, JP-A-60-2452
No. 25, Japanese Patent Laid-Open No. 61-101029, and many other publications.

According to the above-mentioned JP-A-58-171819, in coating a resist or the like as a processing liquid on the surface of a wafer in a photoresist coating step or the like, a liquid surface of a solvent or the like contained in the resist is stabilized, and The exhaust amount by the auto-damper is adjusted to prevent the resist or the like generated around the wafer from adhering to the surface of the wafer again during spin rotation.

(Problems to be solved by the invention) However, the exhaust gas of such a processing apparatus may contain mist of a resist and an organic solvent and adhere to the auto damper. Therefore, the exhaust gas is provided in the exhaust path communicating with the processing chamber. The auto damper and drive system are damaged or malfunction. When the resist solution dropped on the wafer surface is tried to be spin-coated without noticing this failure, there is a problem that the remaining resist floats in the processing chamber and adheres to the wafer surface again.

Further, as a means for solving the above problem, an exhaust sensor for detecting the exhaust state in the processing chamber is provided in the processing chamber,
Means for displaying such that the exhaust gas abnormality is detected and displayed when the exhaust gas becomes abnormal can be considered.

However, when the exhaust damper of the above-mentioned exhaust sensor is closed, an abnormal exhaust is displayed and the processing may stop.

Further, in the method using the exhaust sensor, the automatic damper may also adjust the flow rate of the exhaust gas, so that it is difficult to adjust the exhaust abnormality sensor and there is variation in the adjustment.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide means for preventing mist from adhering to a damper and for immediately detecting an abnormality in the damper.

[Configuration of the invention]

(Means for Solving the Problems) The present invention relates to a spin chuck that holds and rotates an object to be processed, a processing liquid supply unit that supplies a processing liquid to the object to be processed held by the spin chuck, and the spin chuck. In a liquid treatment apparatus including a cup provided so as to cover the circumference of the cup, an exhaust pipe opened to the bottom of the cup and connected to exhaust means, and a drain pipe, a mist removing mechanism for the exhaust pipe. And an adjusting means for adjusting the exhaust amount between the mist removing mechanism and the exhaust means are provided in the exhaust pipe.

In this processing apparatus, the exhaust pipe may be provided with a mist removing mechanism, and the exhaust pipe may be provided with adjusting means for adjusting the exhaust amount between the mist removing mechanism and the exhaust means.

(Operation / Effect) According to the present invention, the mist of the processing liquid that has been scattered / mixed into the exhaust pipe from the processing chamber can be removed by the mist removing mechanism. Therefore, the damper disposed on the downstream side of the mist removing mechanism It is possible to prevent the treatment liquid from adhering to, and to reduce the breakdown.

The waste liquid captured by the mist removing mechanism may be appropriately discharged to the outside of the exhaust pipe system by using drainage means such as a drain pipe.

Also, by providing a sensor that detects the opening and closing of the damper,
When the auto damper system including the drive system is damaged or malfunctions by electrically detecting that the gas flow in the processing chamber has slowed down in the processing step of applying the processing liquid to the object to be processed, It is possible to immediately stop the coating process. In addition, when the processing liquid adhering to the object to be processed is removed by the centrifugal force at the time of rotation, it is possible to electrically detect that the air in the processing chamber is sucked and exhausted to the outside. If the auto-damper system is damaged or malfunctions, it can be stopped immediately. However, since the open / closed state of the on-off valve is detected, there is no "deviation" in time compared to the conventional method using the exhaust sensor, and the response is good.

(Embodiment) An embodiment in which the apparatus of the present invention is applied to a development processing apparatus will be described below with reference to the drawings.

The developing processing apparatus, as shown in FIG.
For example, a nozzle (1a) that ejects a developer containing electrolyte
Further, a cleaning liquid for flushing the developing liquid, for example, a nozzle (1b) for ejecting a rinse liquid is provided in the vertical direction. A circular rotary unit that holds an object to be processed, for example, a wafer (2) at a position facing the tips of the nozzles (1a) and (1b), for example, holds the object to be processed by direct air suction and rotates at a set speed. , For example a wafer chuck (3) is provided.

Around the wafer chuck (3), the cup (4) that can be moved up and down does not scatter around even if the processing liquid discharged from the nozzles (1a) (1b) collides with the wafer (2) and scatters. ) Is provided. The cup (4) is composed of a lower cup (4a) which can be moved up and down and a fixed upper cup (4b).

At the bottom of the lower cup (4a), a drainage pipe (5) is provided downward so that the treated liquid flows to a drainage tank (not shown).

Further, an exhaust mechanism (6) for exhausting the air or atmosphere in the cup (4) to the outside is provided. In this exhaust mechanism (6), the airflow generated in the cup (4) passes through the mist removing mechanism (7) and the automatic damper (9) provided in the exhaust pipe (8) and is exhausted to the outside. An exhaust pump (10) is provided. As shown in FIG. 3, the exhaust pipe (8) has a first exhaust pipe portion (8a) for sucking downward from the inside of the cup (processing chamber) (4) and a first exhaust pipe portion (8a). The second exhaust pipe part (8
b), and the mist removing mechanism (7) is arranged at the connecting portion between the first exhaust pipe portion (8a) and the second exhaust pipe portion (8b). The damper (9) and the exhaust pump (10) are arranged in the second exhaust pipe portion (8b). Further, the mist removing mechanism (7) includes a draining means (7a) for discharging the waste liquid captured by the mist removing mechanism (7).

The automatic damper (9) is configured such that the opening / closing valve (9a) shuts off the exhaust passage by rotating the rotating shaft (9b) and the valve can be opened.

At one end of the rotary shaft (9b), for example, the bottom end in the figure, a rotary drive (1
1), for example, an air cylinder (11a) is provided.

In this air cylinder (11a), a solenoid box (12) for switching air supply is used to supply and stop the supply of air.

Here, the air supply operation system is the air cylinder (11
The rod of a) is extended, and the on-off valve (9a) is configured to shut off the exhaust passage. On the other hand, the supply stop operation system shortens the rod of the air cylinder (11a) and opens / closes the valve (9
a) is configured to open the exhaust passage.

The control of the air cylinder (11a) is performed by a control means such as a CPU (13) via a solenoid box (12).

The CPU (13) also controls the discharge amount of the processing liquid discharged onto the wafer (2) and the rotation speed of the wafer chuck (3).

At the other end of the rotary shaft (9b), when the rotary drive unit (11) shuts off the exhaust passage, a detection means for detecting the shut-off valve (9a), for example, an auto-damper sensor (14).
Is provided.

As shown in FIG. 1, the automatic damper sensor (14) is provided with a linear bar (15) which is cantilevered with a rotating shaft (9b) in a direction perpendicular to the area direction of the on-off valve (9a). There is.

A magnet, for example, a magnetized ferrite magnet (16) is provided at the floating end of the linear bar (15).

Here, the straight bar (15) provided on the on-off valve (9a)
Moves along with the rotational movement of the on-off valve (9a).

A reed switch (17) is provided on the moving path along which the ferrite magnet (16) provided on the linear bar (15) moves.

The reed switch (17) is arranged to switch on when the ferrite magnet (16) arrives.

Here, when the reed switch (17) is switched on by the ferrite magnet (16), the on-off valve (9a) is input to the automatic damper check relay (18) by a signal that the exhaust passage is shut off.

In addition to the cutoff signal, an exhaust sensor (19) is provided to detect an abnormal exhaust when the gas flow in the cup (4) is suppressed. Here, when the exhaust sensor (19) detects an exhaust abnormality, a signal is input to the automatic damper check relay (18) that the air in the cup (4) is not sucked. The auto-damper check relay (18) is formed so as to perform three types of electrical operations, as shown in FIG.

First, as shown in FIG. 2 (A), a drive signal for closing the on-off valve (9a) by the drive force from the drive source and the cup (4).
When the exhaust abnormality signal of the exhaust sensor (19) provided inside and the arrival signal of the on-off valve (9a) detected by the auto-damper sensor (14) provided on the on-off valve (9a) are input, it is stored in advance. The application operation start signal of the developing liquid or the cleaning liquid is output according to the executed program.

Further, as shown in FIG. 2 (B), a release drive signal for opening the on-off valve (9a) by releasing the drive force from the drive source,
When the normal exhaust signal of the exhaust sensor (19) and the signal that the auto-damper sensor (14) cannot detect the on-off valve (9a), for example, the opening signal, are input, the wafer is stored according to the program stored in advance. A rotation operation signal for removing the developing solution or cleaning solution attached to (2) by centrifugal force is output.

Then, as shown in FIG. 2 (c), release of the driving force from the drive source causes a release drive signal for opening the on-off valve (9a),
When the exhaust abnormality signal of the exhaust sensor (19) and the signal that the arrival of the opening valve (9a) are not released by the automatic damper sensor (14) are input, the wafer processing is continued according to the program stored in advance. A processing stop signal for stopping the operation is output. Moreover, the abnormal alarm signal and the lighting display signal are output.

 Next, the operation will be described.

First, it is placed on the wafer (2) and the wafer chuck (3), and is rotated by driving the drive motor (3a) of the wafer chuck (3). The developing solution or the cleaning solution is discharged and applied from the nozzles (1a) and (1b) provided above the surface of the wafer (2). The developing solution or cleaning solution applied on the surface of the wafer (2) passes through the drainage pipe (5) and is stored in, for example, a tank (not shown).

Then, after a predetermined developing time has elapsed, the developing solution is attached to the surface of the wafer (2).

This developing solution is driven by the wafer chuck (3) so as to be shaken off by the high speed rotation and removed.

Further, after the development coating process is completed, the wafer (2)
In order to wash off the developing solution above, the cleaning solution is applied in the same manner as above, and is shaken off and removed in the same manner as above. By the way, when the developing solution or the cleaning solution is applied to the wafer (2), if the air in the cup (4) moves, the liquid level of the developing solution solvent applied to the wafer (2) cannot be kept stable. , Exhaust passage with open / close valve for auto damper (9) (9
Development is performed in the state where the exhaust is stopped by shutting off in b).

On the other hand, when the developer adhering to the wafer (2) is shaken off and removed by applying centrifugal force, the air in the cup (4) must be sucked and exhausted to the outside to fill the cup (4). Since the developing solution or the cleaning solution adheres again, the opening / closing valve is opened to escape from the filled cup (4).

Although the exhaust pipe (8) is opened and closed as described above, the mist of the resist developing solution may adhere to the auto damper (9), causing damage or failure.

The position of the normal on-off valve (9a) should automatically return to the position shown by the chain double-dashed line as shown in FIG. 1, but it is damaged, for example, the rod part of the air cylinder (11a) is damaged, When the exhaust path is shut off regardless of the drive signal, as shown in FIG. 2 (c), in the auto damper check relay (18), the signal from the auto damper sensor (14) is a closing signal, that is, Since the reed switch (17) is switched on, the processing operation of the wafer (2) is stopped according to a predetermined program.

In addition, an abnormal alarm is sounded to inform the operator of this.

The operator investigates the reason why the automatic damper (9) does not operate and the processing exhaust is not performed, and if it is damaged, repair it and press the reset button to continue the processing again.

Although the reed switch and the ferrite magnet are used for the auto damper sensor in the above embodiment, the present invention is not limited to this, as long as it can detect the position of the on-off valve by blocking the exhaust passage, a proximity switch can be used. If so, the position of the on-off valve is detected.

In the above embodiment, the open type circuit is switched on when the on-off valve reaches the position where the exhaust passage is shut off.
When the on-off valve arrives, the position of the on-off valve is detected even in the cross-type circuit that switches off.

In the above embodiment, the ferrite magnet is provided in the direction orthogonal to the area direction of the on-off valve, but the present invention is not limited to this, and the position of the on-off valve can be detected even if it is provided in the direction parallel to the area direction.

As described above, according to the above-described embodiment, since the opening / closing valve position where the exhaust passage is blocked is detected, it is assumed that the opening / closing valve is open when it is not detected, that is, in the cup. Assuming that the gas is sucked and exhausted to the outside, a step of shaking off the processing liquid adhering to the wafer is performed.

Further, when the opening / closing valve does not open due to the driving force from the driving source, the processing of the wafer is automatically stopped, so that the processing cannot be performed in the atmosphere in which the processing solution is suspended, and therefore the shaken-off processing solution is reattached. Will disappear.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an auto-damper exhaust pipe for explaining an embodiment in which the apparatus of the present invention is applied to a developing processing apparatus, and FIG.
1 is an explanatory view of an auto-damper check relay for explaining an operation signal when the on-off valve of FIG. 1 does not operate at a predetermined position, and FIG. 3 is for explaining the entire configuration of the device of FIG. It is a structure explanatory view. 9 …… Auto damper, 9a …… Open / close valve, 9b …… Rotary shaft,
11 …… Rotary drive, 11a …… Air cylinder, 14 ……
Auto damper sensor, 15 …… straight bar, 16 …… ferrite magnet, 19 …… exhaust sensor.

Claims (2)

(57) [Claims] 1. A spin chuck for holding and rotating an object to be processed, a processing liquid supply means for supplying a processing liquid to the object to be processed held by the spin chuck, and a spin chuck provided so as to cover the periphery of the spin chuck. A cup, an exhaust pipe opened to the bottom of the cup and connected to an exhaust means, and a drain pipe, respectively, in the liquid treatment apparatus, the exhaust pipe is provided with a mist removing mechanism, and the mist removing mechanism is provided. A liquid processing apparatus, wherein the exhaust pipe is provided with an adjusting unit for adjusting an exhaust amount between the exhaust unit and the exhaust unit. 2. The liquid processing apparatus according to claim 1, wherein the mist removing mechanism includes a drainage unit that drains the trapped waste liquid.