JPH0684873A - Wafer treatment device - Google Patents

Abstract

PURPOSE:To ensure safety and to prevent environmental pollution during wafer treatment by providing a wafer treatment device which prevents acid gas and alkaline gas from mixing and coming into contact with each other. CONSTITUTION:This device is provided with an airtightly closed treatment bath 2 with a sample insertion port in a lid part, an exhaust duct 3 opened inside the treatment bath 2, an airtightly closed chemical storage tank 5 connected to the exhaust duct 3, an airtightly closed duplicate washing liquid storage tank 6 connected to the exhaust duct 3, a chemical supply circuit 10 which supplies treatment chemical and duplicate washing liquid into the treatment bath 2 from the chemical storage tank 5 or the duplicate washing liquid storage tank 6 and circulates them inside the treatment bath 2, and further collects them into the tank 5 or the tank 6 from inside the treatment bath 2, water supply/drain means 7, 8 which make pure water flow to the treatment bath 2, a new chemical supply means 7' to a chemical storage tank and an exhaust gas cleaning device 9 arranged in a base part of the exhaust duct 3. Processes from chemical treatment of a wafer to water washing thereof are performed in the same treatment bath.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer processing apparatus, and more particularly to a wafer processing apparatus which prevents the danger and environmental pollution due to the gas generated from the chemicals in the chemical treatment of semiconductor wafers.

[0002] For wafer processing performed between various steps in manufacturing a semiconductor device, a solution of acid or alkali which is heated at room temperature or heated is used. Therefore, a mixed reaction occurs between the gaseous acid and alkali generated from the chemical, and a new reaction product is likely to be formed.There is a risk of clogging of the exhaust port caused by deposition of this reaction product, and removal. Environmental pollution due to atmospheric release of the above reaction products has become a problem, and development of a wafer processing apparatus which avoids contact and contact between acidic gas and alkaline gas is desired.

[0003]

2. Description of the Related Art Conventionally, as a means for preventing environmental pollution due to acidic or alkaline gas generated during the manufacture of semiconductor devices, many wafer processing devices used in various manufacturing processes are divided into acid and alkali systems. The method is to collect the exhaust gas of each wafer processing equipment by system and perform exhaust gas treatment such as water washing for each system to remove harmful components such as acid and alkali in exhaust gas and then release them into the atmosphere. It was being done.

On the other hand, in the conventional wafer processing apparatus, as shown in the schematic diagram of FIG. 4, an acid processing tank 52 into which a sulfuric acid (H ₂ SO ₄ ) or the like is introduced is adjacently provided in a wafer processing chamber 51. A water washing tank 53 in which pure water flows and an alkaline treatment tank 54 into which, for example, ammonia water (NH ₄ OH) is introduced are sequentially arranged, and in an upper portion of the acid treatment tank 52 and the alkaline treatment tank 54 in the treatment chamber 51, The exhaust gas cleaning device 59 for an acid gas and the exhaust gas cleaning device 60 for an alkaline gas, each of which has an exhaust duct 57 for an acid gas and an exhaust duct 58 for an alkaline gas, are opened at the ends thereof. In the figure, reference numerals 61 and 62 denote gas discharge ports.

In the wafer processing, a plurality of semiconductor wafers 56 are mounted side by side in a wafer carrier 55, and the wafer carrier 55 is first placed in an acid treatment tank 52 as shown by a flow line m of the wafer carrier 55. It is carried out by a method of dipping for a predetermined time, then pulling it up and moving it, soaking it in the washing tank 53 for a predetermined time, then further pulling it up and moving it and soaking it in the alkali treatment tank 54 for a predetermined time. The semiconductor wafer 56 that has been subjected to the alkali treatment is transferred to a wafer cleaning step (not shown) with the carrier 55 still mounted.

[0006]

[Problems to be Solved by the Invention] However, as described above,
In a conventional wafer processing apparatus in which the same wafer processing chamber 51 is provided with an acid treatment tank tank 52 and an alkali treatment tank 54 whose upper parts are opened, the acid treatment tank tank 52 and the alkali treatment tank 54 are
Even if a dedicated exhaust duct 57 for acid gas and an exhaust duct 58 for alkali gas are provided in the upper part of the exhaust duct, various ducts for wet processing (not shown) are actually connected to the respective ducts so that the exhaust ducts are exhausted. The exhaust gas balance between 57 and 58 becomes unbalanced, and therefore the exhaust duct for acid gas
In some cases, alkali gas may flow into 57, or acid gas may flow into the exhaust duct 58 for alkali gas. Further, when the wafer carrier 55 having the wafer 56 mounted thereon is moved, the surface of the wafer 56 having a large surface area and the acid or alkali liquid adhering to the wafer carrier 55 evaporates, and a large amount of evaporative gas enters the wafer processing chamber 51. Due to the spread, a large amount of acid gas and alkali gas will flow into the exhaust ducts other than the dedicated ones.

Therefore, in the conventional wafer processing apparatus described above, a contact reaction between the acidic gas and the alkaline gas occurs in the exhaust ducts 57 and 58, and reaction products are deposited and deposited in the exhaust ducts 57 and 58. There are problems that the duct is clogged, which impairs safety, and that the reaction products are not properly removed by the exhaust gas cleaning devices 59 and 60, thereby causing environmental pollution.

[0008] Therefore, an object of the present invention is to provide a wafer processing apparatus which prevents the acid gas and the alkaline gas from being mixed with each other, and to secure safety during wafer processing and prevent environmental pollution.

[0009]

To solve the above-mentioned problems, the upper part is covered with a lid having an openable / closable sample insertion port, and a processing liquid is overflowed to a height separating a space of a predetermined size from the lid. A sealed wafer processing tank, an exhaust duct having an end opening in the space, and a sealed chemical storage tank containing processing chemicals to be supplied into the processing tank and connected to the exhaust duct And a closed type co-washing liquid storage tank that stores the co-washing liquid to be supplied into the treatment tank and is connected to the exhaust duct, and the treatment chemicals and the co-washing liquid are the chemical storage tank or the co-washing liquid storage In the chemical liquid supply circuit, a chemical liquid supply circuit having a function of supplying from the tank into the treatment tank, circulating the inside of the treatment tank, and further collecting from the treatment tank into the chemical storage tank or the co-washing liquid tank Inserted into , A water supply means for circulating pure water into the treatment tank, a drainage means from the treatment tank, a means for supplying a new chemical to the chemical storage tank, and an exhaust gas cleaning disposed at the base of the exhaust duct. A wafer processing apparatus according to the present invention, which is equipped with an apparatus, from the chemical treatment of wafers to washing with water in the same processing tank, or the first wafer processing apparatus for acid treatment and the second wafer treatment for alkali having the above structure. This is achieved by the wafer processing apparatus according to the present invention, which has the same wafer processing apparatus as described above in the same processing chamber.

[0010]

FIG. 1 is a block diagram of the essential parts of a wafer processing apparatus for explaining the principle of the present invention. In the figure, 2 is a closed type wafer processing tank, which has a lid 2A to which a first end 3A of an exhaust duct 3 is connected, and the lid 2A is provided with an openable / closable wafer loading / unloading port 4. In addition, 5 is a closed chemical storage tank,
Processing chemicals are stored in the upper part of the exhaust duct 3
End 3C of is connected. Further, 6 is a closed type co-washing liquid storage tank in which a co-washing liquid containing the same chemical as the treatment chemical is stored, and the second end 3B of the exhaust duct 3 is connected to the upper portion. Further, 7 is a water supply pipe for supplying washing water,
7'is a new chemical supply pipe to the chemical storage tank, 8 is a drain pipe, 9
Is an exhaust gas cleaning device. Then, in the wafer processing apparatus of the present invention, the wafer processing tank 2, the chemical storage tank 5, and the co-washing liquid storage tank 6 have a chemical solution supply circuit 10 in which a filter 11 capable of supply, circulation and recovery is built in. The wafer is chemically connected to the wafer and the wafer is washed with water in the same hermetically sealed processing tank 2 collectively.

As described above, in the wafer processing apparatus of the present invention, the chemical processing of the wafer is carried out in the closed type wafer processing tank 2 to which the exhaust duct 3 (3A) is connected, and the processing chemicals and the co-washing liquid are treated. Since the storage tanks 5 and 6 are also of a closed type and connected to the exhaust duct 3 (3B or 3C), most of the chemical gas leaked from the equipment to the outside during the chemical processing of the wafer and the co-washing of the processing container. Disappear. Further, the wafer after the chemical treatment is washed with water in the same wafer treatment tank 2 continuously, and the wafer treatment container 2
Since the wafer to be taken out and the carrier equipped with the wafer have been washed with water, there is almost no generation of chemical gas outside the apparatus due to the movement of the wafer.

As described above, when the wafer processing apparatus having the constitution of the present invention is configured as a wafer processing apparatus in which the acid treatment and the alkali treatment are arranged adjacent to each other and the acid treatment and the alkali treatment are continuously performed. However, the exclusive gas ducts for acidic gas or alkaline gas that are connected to the respective devices do not mix each other's gas, and almost no reaction products are generated by the contact and contact of the acidic gas and the alkaline gas.

Therefore, clogging of the exhaust duct due to precipitation and deposition of reaction products due to contact between the acidic gas and alkaline gas, and release of the reaction product mist into the atmosphere due to defective treatment of the exhaust gas cleaning device are avoided. The safety of the processing process is ensured, and at the same time, environmental pollution due to wafer processing is prevented.

[0014]

EXAMPLES The present invention will be described in detail below with reference to illustrated examples. 2 is a schematic configuration diagram of an embodiment of the wafer processing apparatus of the present invention, and FIG. 3 is a schematic configuration diagram of another embodiment of the same. The same object is denoted by the same reference numeral throughout the drawings.

In FIG. 2 showing one embodiment of the present invention, 12
Is an overflow type closed wafer processing tank, 13 is an exhaust duct, 13A, 13B and 13C are the first, second and third ends of the exhaust duct 13, 14 is a wafer loading / unloading port, and 15 is a closed chemical storage Tank, 16 is a closed type co-washing liquid storage tank, 17 is a water supply pipe, 18 is a drain pipe, 19 is an exhaust gas cleaning device, 20
Is a chemical supply circuit, 21 is a wafer, 22 is a wafer carrier, 23 is a processing chemical, 24 is a co-washing liquid, 25 is a pressure pump, 26
Is a filter, 27 is a new chemical supply pipe, and SV-1 to SV-9 are valves.

A wafer processing apparatus of the present invention, for example, a wafer acid processing apparatus has a structure as shown in FIG. 2, for example, and HNO ₃ is contained as a processing chemical 23 in the sealed chemical storage tank 15. It In addition, it contains a solution used for washing the treatment tank after washing, that is, for co-washing, in order to prevent changes in the concentration of the treatment chemical introduced by replacing the water accumulated in every corner of the treatment tank 12 after washing with water. The closed type co-washing liquid storage tank 16 stores HNO ₃ as the co-washing liquid, which is similar to the above-mentioned treatment chemical. Then, the wafer processing tank 12, the chemical storage tank 15 and the co-washing liquid storage tank 16 are provided with a dedicated exhaust gas cleaning device 19 in the same system, that is, at the base via the exhaust duct end portions 13A, 13C, 13B at the upper part. It is connected to the exhaust duct 13 of the acid system.

When processing the wafer 21, first the valve is used.
Only SV-4 and SV-2 are opened to fill the wafer processing tank 12 with HNO _{3 of the} processing chemical 23, and then the wafer loading / unloading port 14 is opened to process the wafer 21 mounted on the wafer carrier 22.
The wafer is held by being dipped therein, and the wafer loading / unloading port 14 is closed.

Next, the valves SV-1, SV-3, SV-4, SV-
5, SV-6, SV-7, SV-8 are closed, only SV-2 is opened, and the pressure pump 25 is driven. In this state, the processing chemical 23 circulates in the wafer processing tank 12 via the pressure feed pump 25 and the filter 26. The circulation of the treatment chemical 23 is continued for a predetermined time to perform a predetermined acid treatment.

Then, when the processing is completed, the valve SV
-2, SV-3, SV-4, SV-5, SV-7, SV-8 are closed, SV-1, SV-6 are opened, pressure pump 25 is driven, and processing chemicals 23 in processing tank 12
Are collected in the chemical storage tank 15.

Then, the valve SV-7 is opened to supply pure water from the water supply pipe 17, and the valves SV-1, SV-3, SV-4, SV-5 and SV are supplied.
-6, SV-8 are closed, valve SV-2 is opened, pressure pump 25 is driven, pure water is circulated in wafer processing tank 12 through pressure pump 25 and filter 26, and wafer 21
Wash with pure water.

Then, after cleaning with pure water is completed, the valve SV is
-8 is opened, SV-1, SV-3, SV-4, SV-5, SV-6 is closed for a certain period of time SV-2 is opened, the pressure pump 25 is driven, and the processing tank 12 and the piping The pure water is discharged from the drain pipe 18.

Then, the wafer loading / unloading port 14 is opened, and the wafer 21 after cleaning with pure water and the carrier 22 on which the wafer 21 is loaded are taken out from the processing tank 12 and transferred to another processing apparatus. Next, the wafer loading / unloading port 14 is closed, and the valve SV-2
And SV-3 open, valves SV-1, SV-4, SV-5, SV-6, SV-7,
With the SV-8 closed, the co-washing liquid is pressure-fed to fill the processing tank 12 for co-washing and cleaning, then the valves SV-1 and SV-5 are opened, and the valves SV-2, SV-3, With the SV-4, SV-6, SV-7 and SV-8 closed, the pressure feed pump 25 is driven to collect the co-washing liquid 24 into the co-washing liquid storage container 16.

In this state, the pure water remaining in the treatment tank 12 and the pipe is replaced by the co-washing liquid 24, and then the treatment tank 12 is replaced.
When the treatment chemical 23 is introduced into the inside 12, the change in the concentration thereof is suppressed.

As described above, in the above-mentioned wafer processing apparatus according to the present invention in which the wafer 21 is processed, the processing chemicals and HNO _{3 as the} co-washing liquid are all dedicated acid exhaust ducts.
Since it is handled in a closed container connected to 13, the amount of gas containing HNO ₃ leaking to the outside of the device can be suppressed to an extremely small amount. Further out from the apparatus carrier 22 for mounting the wafer 21 and it is processed, since the pure water cleaning is performed after the end, drawn from the semiconductor wafer and the carrier device, HNO ₃ to diffuse to the outside of the device Almost no gas containing is generated. After repeated dozens of times, HNO ₃ for co-washing is discharged from drain pipe 18, HNO ₃ for treatment is for co-washing, SV-9 opens and new HNO ₃ from new chemical supply pipe 27. ₃ is supplied.

FIG. 3 is a schematic structural view of another embodiment of the present invention in which an acid treatment tank and an alkali treatment tank are arranged adjacent to each other in the same treatment chamber. In the figure, 112 is a closed acid treatment tank, 11
3 is an exhaust duct for acid gas, 113A, 113B and 113C are its first, second and third ends, 114 is a wafer loading / unloading port, 11
5 is a sealed acid storage tank, 116 is a sealed acid co-washing solution storage tank, 117 is a water supply pipe, 118 is a drain pipe, 119 is an acid gas exhaust gas cleaning device, and 120 is the same circuit configuration as in the above embodiment. The acid treatment chemical supply circuit that is provided, 121 is an acidic chemical supply pipe, 212 is a closed alkaline treatment tank, 213 is an exhaust duct for alkali gas, and 213A, 213B, and 213C are the first and second thereof.
The third end, 214 is a wafer loading / unloading port, 215 is a sealed alkaline storage tank, 216 is a sealed alkaline co-washing liquid storage tank, 217 is a water supply pipe, 218 is a drain pipe, and 219 is an exhaust gas cleaning device for alkaline gas. , 220 is a chemical supply circuit for alkaline treatment having the same circuit configuration as the above-mentioned embodiment, 221 is an alkaline chemical supply pipe, 123 is an acid treatment liquid, 223 is an alkali treatment liquid, 21 is a wafer, 22 is a wafer carrier, 1 is Shows the processing chamber.

In this embodiment, as shown in the figure, the acid treatment device and the alkali treatment device of the wafer 21 having the same structure as the wafer treatment device of the above-mentioned embodiment are combined to perform the acid treatment and the alkali treatment of the wafer. An integrated wafer processing device is continuously formed. The processing method in each processing tank is the same as that in the above-mentioned embodiment.

In this apparatus, for example, first, the acid treatment bath 112 is filled with the acid treatment liquid 123, the wafer loading / unloading port 114 of the treatment bath 112 is opened, and the wafer 21 mounted on the wafer carrier 22 is marked with an arrow. As shown by the chain line m, the wafer is immersed and held in the acid treatment liquid 123, and the wafer loading / unloading port 114
Is closed, and an acid treatment is performed for a predetermined time while circulating the treatment liquid 123.

Next, after recovering the acid treatment liquid 123 in the acid treatment tank 112 into the closed type acid storage tank 115, the acid treatment tank 112 is recovered.
Purified water is circulated in the inside for washing with water. Then, the processing tank 11
Open the wafer loading / unloading port 114 of No. 2 and pull out the wafer 21 and the carrier 22 that have been washed with water, move them as shown by the chain line m with the arrow, and open the wafer loading / unloading port 214 of the alkali treatment tank 212 to open the inside of the tank 212. It is dipped and held in the alkaline treatment liquid 223 filled with the solution.

Next, the wafer loading / unloading port 214 of the alkali treatment tank 212 is closed, and the alkali treatment is performed for a predetermined time while circulating the treatment liquid 223. Then, the alkaline treatment tank 212
The alkaline treatment liquid 223 in the sealed alkaline storage container 215
After the recovery, the pure water is circulated in the processing tank 212 to wash the wafer 21 and the carrier 22 with water.

Then, the wafer loading / unloading port 214 is opened, and the wafer 21 and the wafer carrier 22 which have been washed with water are withdrawn and moved to the next step, and the wafer processing is completed.
In this apparatus, as described in the above process description, the wafer 21 mounted on the carrier 22 is sealed in the acid treatment tank 112.
When the wafer is inserted into the alkaline treatment tank 212, the respective wafer loading / unloading ports 114 or 214 are opened to expose the processing liquid surface into the processing chamber 1.
3 or 213 ends 113A or 213A of the processing tank 112 or
Since it is opened in 212, the air in the processing chamber 1 flows toward the inside of the processing tank 112 or 212 when the respective wafer loading / unloading ports 114 or 214 are opened.
Almost no acid or alkali gas flows into the processing chamber 1. In addition, since the wafer 21 and the carrier 22 that have undergone the respective treatments are drawn out of the treatment apparatus and moved after finishing the washing with water, an acid or alkali gas is released from the surface of the wafer 21 and the carrier 22 into the treatment chamber 1. It never happens. Further, the acid treatment liquid, the alkali treatment liquid and the respective co-washing liquids to be stored are also housed in the hermetically-sealed storage containers connected to the exhaust ducts dedicated to the acid or alkali, respectively, so these storage containers 115, 116, 215, 216
Acid or alkali gas leaking into the processing chamber 1 from the above is not generated. Therefore, the acid and alkali gas are not mixed at a high concentration through the processing chamber 1 and drawn into the acid or alkali exhaust duct 113 or 213. Therefore, the clogging of the duct and the environmental pollution due to the reaction product formed by the contact of the acidic gas and the alkaline gas are prevented.

[0031]

As described above, according to the wafer processing apparatus of the present invention, even if the acid treatment and the alkali treatment of the wafer are performed in the vicinity of each other, the reaction product is formed by the contact and contact of the acidic gas and the alkaline gas. Is almost gone.

Therefore, in the wafer processing for manufacturing the semiconductor device, the reaction product does not deposit and accumulate in the exhaust duct to reduce the exhaust efficiency of the duct, and the acidic gas and the alkaline gas are used exclusively for the respective cases. Sufficiently removed by exhaust gas cleaning equipment. Therefore, the present invention greatly contributes to improvement of safety in wafer processing and prevention of environmental pollution.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of a wafer processing apparatus for explaining the principle of the present invention.

FIG. 2 is a schematic configuration diagram of an embodiment of the wafer processing apparatus of the present invention.

FIG. 3 is a schematic configuration diagram of another embodiment of the wafer processing apparatus of the present invention.

FIG. 4 is a schematic configuration diagram of a conventional wafer processing apparatus.

[Explanation of symbols]

 2 Closed wafer processing tank 2A Lid 3 Exhaust duct 3A 1st end of exhaust duct 3B 2nd end of exhaust duct 3C 3rd end of exhaust duct 4 Wafer loading / unloading port 5 Sealed chemical storage tank 6 Closed type co-washing liquid storage tank 7 Water supply pipe 7'New chemical supply pipe 8 Drain pipe 9 Exhaust gas cleaning device 10 Chemical liquid supply circuit 11 Filter

Claims (2)

[Claims] 1. A sealed wafer processing tank, the upper part of which is covered with a lid having an openable / closable sample insertion port, and a processing liquid is filled up to a height separating a space of a predetermined dimension from the lid by an overflow method. An exhaust duct having a terminal end opening in the space, a closed type chemical storage tank containing the processing chemicals to be supplied into the processing tank and connected to the exhaust duct, and a supply tank into the processing tank. A closed type co-washing liquid storage tank containing a washing liquid and connected to the exhaust duct, and supplying the treatment chemicals and the co-washing liquid into the treatment tank from the chemical storage tank or the co-washing liquid storage tank, and A chemical liquid supply circuit having a function of circulating the inside of the treatment tank and further recovering from the treatment tank into the chemical storage tank or the co-washing liquid tank, a filter inserted in the chemical liquid supply circuit, and the treatment tank Distribute pure water to For treating chemicals on a wafer, which comprises: a water supply means for discharging, a drainage means from the treatment layer, a means for supplying a new chemical to the chemical storage tank, and an exhaust gas cleaning device arranged at the base of the exhaust duct. A wafer processing apparatus characterized in that everything from cleaning to washing is performed in the same processing tank. 2. A wafer having the first wafer processing apparatus for acid treatment and the second wafer processing apparatus for alkali treatment having the structure according to claim 1 in the same processing chamber. Processing equipment.