JP2002253950A - Apparatus for treating substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate treating apparatus for preventing an outer peripheral member surrounding a liquid waste tank filled with liquid waste from a treating tank from being corroded by the liquid waste while the apparatus cost is kept inexpensive even when the liquid waste is overflowed from the upper part of the liquid waste tank. SOLUTION: The liquid waste tank for storing the liquid waste from the treating tank 10 is made from a material showing corrosion resistance to the liquid waste. A housing 28 surrounding the liquid waste tank is made from another material showing lower corrosion resistance to the liquid waste than the material of the liquid waste tank. A liquid waste sensor 36 is arranged for detecting the liquid waste which is overflowed from the upper part of the liquid waste tank and flows between the liquid waste tank and the housing 28.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing apparatus for processing various substrates such as a semiconductor substrate, a glass substrate for a flat panel display such as a liquid crystal display device, a glass substrate for a photomask, and a substrate for an optical disk with a processing liquid. .

[0002]

2. Description of the Related Art In a so-called one-bus type substrate processing apparatus in which substrates are sequentially processed by a plurality of different types of processing liquids in one processing tank, the substrate is loaded into and held in the processing tank. A plurality of processing liquids are sequentially supplied to the processing tank, and the inside of the processing tank is sequentially filled with the respective processing liquids, and a series of processing is performed so that the substrate is sequentially immersed in the plurality of processing liquids. In such a substrate processing apparatus, the processing liquid is continuously introduced into the processing tank from the bottom of the processing tank, and the processing liquid overflows from the top of the processing tank, so that the inside of the processing tank is filled with the processing liquid. To When changing the type of the processing liquid, the next processing liquid is supplied to the processing tank filled with the previous processing liquid, and the previous processing liquid is supplied to the processing tank by the next processing liquid flowing into the processing tank. It is pushed out from the top and overflowed so that the inside of the processing tank is replaced with the next processing liquid.

In the above-described substrate processing apparatus, the processing liquid that overflows from the upper portion of the processing tank flows into an overflow receiving portion provided on the outer periphery of the upper portion of the processing tank, and the liquid in the apparatus is discharged from the overflow receiving portion. Spilled into tank. A drain pipe is connected to and connected to the bottom of the drain tank, and the drain pipe is connected to a flow path switch having a plurality of switching valves for switching a drain path for each type of processing liquid. Connected to the entrance side. Then, the drainage stored in the drainage tank passes through the drainage pipe and is discharged out of the apparatus via the flow path switch.

Further, the above-mentioned substrate processing apparatus is configured such that a periphery of a processing tank and a drainage tank is surrounded by a housing (outer peripheral member). The drainage tank and the drainage pipe which come into contact with the drainage are made of a material having corrosion resistance to the drainage, for example, PVDF (vinylidene fluoride resin),
The housing is made of vinyl chloride resin, polypropylene, steel plate, or the like from the viewpoint of cost, while being made of PTFE (fluorinated ethylene resin) or the like.

[0005]

In the above-described substrate processing apparatus, when all the switching valves are closed due to some trouble in the flow path switching device, the drainage stored in the drainage tank is drained. Rather than being discharged to the outside of the apparatus through the liquid pipe through the liquid pipe, the liquid overflows from the upper portion of the drainage tank and flows into and stays between the drainage tank and the housing. In this case, when the drainage is a highly corrosive chemical such as ozone water or a strong acid such as nitric acid, there is a problem that the housing is corroded by the drainage.

[0006] Such a problem is caused by changing the material of the housing,
The problem can be solved by changing to a material having corrosion resistance to a chemical solution, but such a material is expensive and the equipment cost is high, so that it is not practical.

The present invention has been made in view of the above-mentioned circumstances, and while the cost of the apparatus is kept low, even if the drainage overflows from the upper part of the drainage tank, It is an object of the present invention to provide a substrate processing apparatus that can prevent the outer peripheral member from being corroded by drainage.

[0008]

According to the first aspect of the present invention,
At least the inner surface is formed of a material having corrosion resistance to the drainage, a drainage tank for supplying a processing liquid to the substrate and inflowing a drainage flowing out of a processing unit for processing the substrate, and at least the inner surface is for the drainage. A drain pipe formed of a material having corrosion resistance and communicating with the bottom of the drain tank to discharge the drain liquid flowing into the drain tank to the outside of the apparatus; and a drain pipe compared to the material of the drain tank. An outer peripheral member formed of a material having low corrosion resistance against the drainage tank, the outer peripheral member surrounding the drainage tank, and overflowing from the upper part of the drainage tank and flowing between the drainage tank and the outer peripheral member. And a detecting means for detecting the drained liquid.

According to a second aspect of the present invention, in the substrate processing apparatus of the first aspect, the substrate processing apparatus is formed of a material having lower corrosion resistance to the drainage liquid than the material of the drainage pipe, and overflows from the upper part of the drainage tank. And a preliminary drain pipe for discharging the drain liquid flowing between the drain tank and the outer peripheral member.

According to a third aspect of the present invention, in the substrate processing apparatus of the second aspect, the preliminary drain pipe is disposed so as to surround a periphery of the drain pipe. And a double pipe is formed, and a space between the inner peripheral surface of the preliminary drainage pipe and the outer peripheral face of the drainage pipe overflows from the upper part of the drainage tank and flows between the drainage tank and the outer peripheral member. It is characterized by being a liquid passage.

In the substrate processing apparatus according to the first aspect of the present invention, the drainage stored in the drainage tank overflows from the upper portion of the drainage tank and flows between the drainage tank and the outer peripheral member. In any case, the detection means detects that the drainage has flowed between the drainage tank and the outer peripheral member. Therefore, if appropriate measures such as immediately stopping the processing of the substrate in the processing section and stopping the drainage of the drainage from the processing section are taken, the drainage will remain between the drainage tank and the outer peripheral member. You don't have to. Further, if a treatment such as washing the outer peripheral member with pure water to wash out the drainage is performed, the drainage does not remain on the outer peripheral member.
For this reason, even if the outer peripheral member is formed of a material having low corrosion resistance to drainage, and the drainage is a highly corrosive chemical,
The outer peripheral member is not corroded by the drainage.

In the substrate processing apparatus according to the second aspect of the present invention,
The drainage that overflows from the upper part of the drainage tank and flows between the drainage tank and the outer peripheral member is discharged through the auxiliary drainage pipe.

In the substrate processing apparatus according to the third aspect of the present invention,
The drainage which overflows from the upper part of the drainage tank and flows between the drainage tank and the outer peripheral member is discharged through a passage formed between the inner peripheral surface of the preliminary drainage pipe and the outer peripheral surface of the drainage pipe. You. And since a preliminary | backup drainage pipe and a drainage pipe comprise a double pipe, the space for piping may be small.

[0014]

Preferred embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show an example of an embodiment of the present invention. FIG. 1 is a view schematically showing a schematic configuration of a substrate processing apparatus. FIGS. 2 and 3 show a substrate processing apparatus. It is the figure which looked at from the front and the side, respectively. In FIG. 2, the housing and the drainage tank are shown in cross section, and in FIG. 3, the housing is shown in cross section and the drainage tank is shown in a partially broken cross section. In FIGS. 2 and 3,
The illustration of the substrate supporting / elevating mechanism and the processing liquid supply piping system is omitted.

This substrate processing apparatus has one processing tank 10 for processing a substrate W. A plurality of types of processing liquids are sequentially supplied into the processing tank 10, and the inside of the processing tank 10 is filled with the respective processing liquids in turn while the liquid is replaced. Then, the substrate W carried into and held in the processing bath 10 is sequentially immersed in a plurality of types of processing liquids and processed. An overflow receiver 12 is provided integrally with the upper portion of the processing tank 10 so as to make a circuit around the outer periphery, and the waste liquid overflowing from the upper portion of the processing tank flows into the overflow receiver 12. It has become.

As shown in FIG. 2, the overflow receiving portion 12 is partially open on the front side, and the drainage guide plate 14 having a width larger than the opening width is provided as shown in FIG. Overflow receiver 1
2 is attached so as to project forward from the bottom surface. A drainage tank 16 (not shown in FIG. 1) having a width equivalent to that of the drainage guide plate 14 is provided directly below the drainage guide plate 14. The waste liquid that overflows from the upper part of the processing tank 10 and flows into the overflow receiving part 12 flows out of the opening in the front of the overflow receiving part 12, flows on the drain guide plate 14, and flows from the front end thereof. It flows down and flows into the drainage tank 16.

A drainage outflow pipe 18 is connected to the bottom of the drainage tank 16, and a drainage tank 20 having an open top surface is provided below the drainage tank. Outflow pipe 18
The lower end outlet of the bottom surface faces the inside of the drainage tank 20. The drainage flowing into the drainage tank 16 is discharged to the drainage outflow pipe 18.
And flows down from the lower end outlet of the drainage outflow pipe 18 into the drainage tank 20, and is stored in the drainage tank 20.

A drain pipe 22 is connected to and connected to the bottom of the drain tank 20. The drain pipe 22 has a plurality of switching valves 26 for switching the drain path for each type of processing liquid.
a, 26b, 26c, and 26d are connected to the inlet side of the flow path switch 24. The drainage stored in the drainage tank 20 passes through the drainage pipe 22, and the switching valves 26 a, 26 b, which are selectively opened according to the type of the processing liquid, of the flow path switch 24. The liquid passes through 26c or 26d, and is discharged to the outside of the apparatus through the drainage path.

The processing tank 10 and the drainage tank 20 are surrounded by a housing (peripheral member) 28. Drainage passages 30 and 32 are formed between the outer side surface of the drainage tank 20 and the inner side surface of the housing 28 and between the outer bottom surface of the drainage tank 20 and the inner bottom surface of the housing 28, respectively. I have. Also, the drain pipe 22
A preliminary drain pipe 34 having an inner diameter larger than the outer diameter of the drain pipe 22 is provided so as to surround the periphery of the drain pipe 22, and the preliminary drain pipe 34 and the drain pipe 22 constitute a double pipe. ing. A passage through which drainage flows is formed between the inner peripheral surface of the preliminary drainage pipe 34 and the outer peripheral surface of the drainage pipe 22, and the passage and the drainage passage 32 communicate with each other. Also, the drain passage 30
A drain sensor 36 for detecting drain is provided near the lower part of the sensor. Since the drainage sensor 36 does not normally come into contact with the drainage, it is not necessary to manufacture the drainage sensor 36 from a material having corrosion resistance to the drainage.

In this embodiment, the auxiliary drain pipe 34 is arranged so as to surround the drain pipe 22 so as to form a double pipe. The drainage passage 32 may be connected to a position different from the position where the nozzle 22 is mounted.

In this apparatus, the overflow receiving portion 1 of the processing tank 10
The drainage tank 16, the drainage outflow pipe 18, the drainage tank 20, and the drainage pipe 22 in which the drainage from the tank 2 constantly flows are made of a material having corrosion resistance to the drainage, for example, strong acid such as ozone water and nitric acid, For example, it is formed of PVDF, PTFE, or the like. Alternatively, the inner surfaces of those components are PVDF, P
Coated with TFE or the like. On the other hand, the housing 28 is formed of a relatively inexpensive material having lower corrosion resistance to drainage than the drainage tank 20, the drainage tube 22, and the like, such as a vinyl chloride resin, a polypropylene, and a steel plate.

In the substrate processing apparatus having the above-described structure, some inconvenience occurs on the downstream side of the drainage tank 20. For example, the failure of the switching valves 26a to 26d and the malfunction of the drainage tank 20 When the drainage stored in the drainage tank 20 is not discharged to the outside of the apparatus through the drainage path, the drainage tank 20 becomes full of the drainage liquid, and the drainage overflows from the upper part of the drainage tank 20. put out. The drain liquid overflowing from the upper part of the drain tank 20 flows into the drain passage 30 between the drain tank 20 and the housing 28. Then, when the drainage overflowing from the drainage tank 20 starts to accumulate in the drainage passage 30, the drainage sensor 36 detects the drainage and issues an alarm.

When drainage is detected by the drainage sensor 36, for example, the processing of the substrate in the processing tank 10 is automatically stopped immediately, and the drainage of the drainage from the processing tank 10 is stopped. In addition, the operator discharges the drainage collected in the drainage passage 30 through the drainage passage 32 and a passage between the outer peripheral surface of the drainage pipe 22 and the inner peripheral surface of the preliminary drainage pipe 34, through a bypass passage or the like. Discharge outside. Therefore, the drainage is discharged to the drainage tank 2
The stagnation between the zero and the housing 28 does not occur. Further, the operator cleans the inside of the housing 28 with pure water to wash out the drainage. Therefore, even if the housing 28 is formed of a material having low corrosion resistance to drainage, the housing 28 is not corroded by drainage.

[0025]

When the substrate processing apparatus according to the first aspect of the present invention is used, even if the drainage from the processing tank fills the drainage tank and overflows from the upper part thereof, the drainage tank can be used. Can be prevented from being corroded by the drainage. Further, since the outer peripheral member can be formed of a material having low corrosion resistance against drainage, the apparatus cost can be reduced.

In the substrate processing apparatus according to the second aspect of the present invention,
The waste liquid that overflows from the upper part of the drain tank and flows between the drain tank and the outer peripheral member can be quickly discharged out of the apparatus.

[0027] In the substrate processing apparatus according to the third aspect of the present invention,
The space for the piping system for discharging the waste liquid is reduced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of an embodiment of the present invention and schematically illustrating a schematic configuration of a substrate processing apparatus.

FIG. 2 is a view of the substrate processing apparatus shown in FIG. 1 as viewed from the front, and is a view showing a cross section of a housing and a drainage tank.

FIG. 3 is a side view of the substrate processing apparatus shown in FIG. 1, showing a housing in cross section and a drain tank in a partially broken cross section.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Processing tank 12 Overflow receiving part 14 Drainage guide plate 16 Drainage tank 18 Drainage outflow pipe 20 Drainage tank 22 Drainage pipe 24 Flow path switching device 26a, 26b, 26c, 26d Switching valve 28 Housing (outer peripheral member) 30, 32 Drain passage 34 Preliminary drain pipe 36 Drain sensor W Substrate

Claims (3)

[Claims] 1. A drain tank, wherein at least an inner surface is formed of a material having corrosion resistance to drainage, and a drainage tank through which wastewater flowing out of a processing unit that supplies a processing liquid to the substrate and processes the substrate is provided. Is formed of a material having corrosion resistance against drainage, and is connected to the bottom of the drainage tank to discharge drainage flowing into the drainage tank to the outside of the device; and a material of the drainage tank. An outer peripheral member formed of a material having lower corrosion resistance against drainage than the outer peripheral member surrounding the drainage tank, wherein the drainage tank overflows from an upper part of the drainage tank and the outer peripheral member. A substrate processing apparatus having a detecting means for detecting a drained liquid flowing between the substrate processing apparatus and the apparatus. 2. The substrate processing apparatus according to claim 1, wherein the substrate is formed of a material having lower corrosion resistance to drainage than a material of the drainage pipe, and overflows from an upper part of the drainage tank to form the drainage tank and the drainage tank. A substrate processing apparatus, comprising: a preliminary drainage pipe for discharging a drained liquid flowing between the outer peripheral member and the outer peripheral member. 3. The substrate processing apparatus according to claim 2, wherein the preliminary drain pipe is disposed so as to surround a periphery of the drain pipe, and a double pipe is formed by the preliminary drain pipe and the drain pipe. The space between the inner peripheral surface of the preliminary drainage pipe and the outer peripheral surface of the drainage pipe is a passage for drainage overflowing from the upper part of the drainage tank and flowing between the drainage tank and the outer peripheral member. A substrate processing apparatus characterized by the above-mentioned.