KR20100061028A

KR20100061028A - Chemical mixing apparatus

Info

Publication number: KR20100061028A
Application number: KR1020080119898A
Authority: KR
Inventors: 유재혁
Original assignee: 세메스 주식회사
Priority date: 2008-11-28
Filing date: 2008-11-28
Publication date: 2010-06-07

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning liquid mixing apparatus, and more particularly, to a cleaning liquid mixing apparatus capable of shortening the time required for mixing a cleaning liquid required for cleaning a semiconductor wafer to a predetermined concentration.

In the cleaning liquid mixing apparatus according to the embodiment of the present invention, an IPA supplied through a separate pipe from the outside and a mixing tank in which ultrapure water is stored, and a nitrogen gas supplied from the outside are injected into the mixing tank to generate bubbles. As a result, the bubble generator includes a bubble generator for smoothly mixing IPA and ultrapure water in the mixing tank by the bubbles.

Description

Cleaning liquid mixing apparatus

The present invention relates to a cleaning liquid mixing apparatus, and more particularly, to a cleaning liquid supply apparatus capable of shortening the time for mixing the cleaning liquid when mixing the cleaning liquid required to clean the semiconductor wafer, and improving the mixing effect of the cleaning liquid. It is about.

Generally, a semiconductor device is manufactured by forming a predetermined film on a wafer and forming the film in a pattern having electrical properties. The pattern is formed by sequential or repeated performance of unit processes such as film formation, photolithography, etching, ion implantation, polishing, and the like. During the process described above, foreign substances such as compounds or dusts remain on the surface of the wafer, which may cause malfunction of semiconductor devices or other various problems.

Therefore, in order to improve the quality of the semiconductor device, a cleaning process must be performed. Conventional cleaning methods may be classified into wet scrubbing using chemical liquids, dry scrubbing using gases, mechanical cleaning using fine particles, and the like. Among these methods, a wet cleaning method also includes a method using an IPA mixed solution which cleans a wafer using a cleaning solution obtained by mixing IPA (Iso Propyl Alcohol) and ultrapure water (DIW: Deionized Water) at a predetermined concentration.

In general, the mixing device for mixing IPA and ultrapure water is a nozzle for mixing the first mixing tank and the second mixing tank, the circulation unit, the chemical liquid of the first mixing tank and the chemical liquid of the second mixing tank mixed with IPA and ultrapure water supplied from the outside. It may include a supply unit for supplying to.

IPA and ultrapure water are respectively supplied to the first mixing tank and the second mixing tank, and the other mixing tank is ready for the cleaning liquid exchange while the cleaning liquid is supplied from the mixing tank to the nozzle.

The circulation unit circulates the cleaning liquid of the first mixing tank and the cleaning liquid of the second mixing tank with each other, or circulates the cleaning liquid in each of the mixing tanks so that the IPA and the ultrapure water in the mixing tank can be smoothly mixed. To this end, the circulation part may include a pump. When mixing IPA and ultrapure water using a pump as in the related art, there is a problem in that it takes a long time to mix the cleaning liquid.

The present invention has been made to solve the above problems, when mixing the cleaning liquid for cleaning the semiconductor element, it is possible to shorten the time that the cleaning liquid is mixed, the cleaning liquid mixing apparatus that can improve the mixing effect of the cleaning liquid The purpose is to provide.

The objects of the present invention are not limited to the above-mentioned objects, and other objects that are not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, the cleaning liquid mixing apparatus according to an embodiment of the present invention is a mixing tank in which the IPA and ultrapure water is stored, and nitrogen gas supplied from the outside into the mixing tank By injecting bubbles to be generated, the bubble generator includes a bubble generator to smoothly mix the IPA and ultrapure water in the mixing tank by the bubbles.

Specific details of other embodiments are included in the detailed description and the drawings.

According to the washing | cleaning liquid mixing apparatus by this invention, there exist one or more of the following effects.

First, the time required for mixing the cleaning liquid can be shortened.

Second, it is possible to improve the mixing effect of the cleaning liquid, thereby improving the quality of the semiconductor device.

The effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

Specific details of other embodiments are included in the detailed description and the drawings. Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms, and only the embodiments make the disclosure of the present invention complete, and the general knowledge in the art to which the present invention belongs. It is provided to fully inform the person having the scope of the invention, which is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Hereinafter, the cleaning solution mixing apparatus according to the embodiment of the present invention with reference to the accompanying drawings will be described in detail.

1 is a view schematically showing the configuration of a cleaning liquid mixing device according to an embodiment of the present invention.

As shown in FIG. 1, the cleaning solution mixing apparatus according to an embodiment of the present invention is mixed by the cleaning solution mixing unit 40, and the cleaning solution mixing unit 40 that generate a cleaning solution having a predetermined concentration by mixing IPA and ultrapure water. The cleaning solution supply unit 80 may be configured to supply the cleaned solution to the nozzle 90.

The cleaning solution mixing unit 40 may include a mixing tank. The mixing tank may be connected through the IPA supply part 2 and the IPA supply pipe 20 to supply the IPA, and may be connected through the ultrapure water supply part 3 and the ultrapure water supply pipe 30 to supply the ultrapure water. FIG. 1 illustrates a case in which the cleaning liquid mixing unit 40 includes two mixing tanks, that is, the first mixing tank 50 and the second mixing tank 60. In this case, the first mixing tank 50 may be used. ) And the second mixing tank 60 may be configured in parallel, the IPA supply pipe 20 may be divided into two and connected to the first mixing tank 50 and the second mixing tank 60, respectively. An IPA supply valve 21 is provided on the IPA supply pipe 20. By opening and closing the IPA supply valve 21, the IPA can be supplied or blocked into the first mixing tank 50 and the second mixing tank 60. .

The ultrapure water supply pipe 30 may also be branched into two like the IPA supply pipe 20 and connected to the first mixing tank 50 and the second mixing tank 60, respectively. The ultrapure water supply valve 31 is provided on the ultrapure water supply pipe 30. The ultrapure water supply valve 31 may be opened or closed to supply or block the ultrapure water into the first mixing tank 50 and the second mixing tank 60. . The IPA supply valve 21 or the ultrapure water supply valve 31 may be located at a point before the IPA supply pipe 20 or the ultrapure water supply pipe 30 is branched into two, or the IPA supply pipe 20 or the ultrapure water supply The pipe 30 may be located at a point after the branching into two. 1 shows that the IPA supply valve 21 is positioned at the point before the IPA supply pipe 20 is branched into two, and the ultrapure water supply valve 31 is positioned at the point before the ultrapure water supply pipe 30 is branched into two. It shows where it is located.

One or more level sensors 51 and 61 may be provided in the first mixing tank 50 and the second mixing tank 60, respectively. The level sensors 51 and 61 detect the flow rate of ultrapure water supplied into each mixing tank so that the ultrapure water can be supplied to the mixing tank as much as desired.

According to one embodiment of the present invention, each mixing tank is connected to the nitrogen gas supply unit 1 through the nitrogen gas supply pipe 10. The nitrogen gas supply pipe 10 is a pipe for supplying nitrogen gas N ₂ into each mixing tank, and may be connected to the lower portion of each mixing tank. A nitrogen gas supply valve 11 is provided on the nitrogen gas supply pipe 10, and by opening and closing the nitrogen gas supply valve 11, nitrogen gas can be supplied or blocked into the mixing tank. The supply of nitrogen gas into the mixing tank can for example take place after the IPA and the ultrapure water are fed into the mixing tank.

On the other hand, the nitrogen gas supply pipe 10 may be connected to the bubble generator (52, 62) included in each mixing tank. Each bubble generator (52, 62) may be located in the lower side of each mixing tank (50, 60), may be implemented in a form that is connected to the lower side of the outside of each mixing tank (50, 60). Bubble generators 52 and 62 positioned below each of the mixing tanks 50 and 60 inject nitrogen gas supplied through the nitrogen gas supply pipe 10 into each of the mixing tanks 50 and 60, thereby supplying nitrogen gas. By allowing bubbles to be generated.

Specifically, when the nitrogen gas supply valve 11 is opened while the IPA and the ultrapure water are supplied to each of the mixing tanks 50 and 60, the nitrogen gas supplied from the outside moves along the nitrogen gas supply pipe 10 to each of the mixing tanks 50 and 60. When the nitrogen gas is supplied into each of the mixing tanks 50 and 60 in a state where IPA and ultrapure water are mixed in each of the mixing tanks 50 and 60, nitrogen gas is supplied to the mixing tanks 50 and 60. Due to the bubbles generated, due to the generated bubbles are mixed in each mixing tank (50, 60), which is to mix the IPA and ultrapure water. In this way, by using the bubbles generated by the nitrogen gas, the mixing time can be shortened compared to the case where the IPA and ultrapure water in each of the mixing tanks 50 and 60 are circulated using the pump 81 and mixed at a constant concentration. have.

In addition, the cleaning liquid supply pipe 70 is connected to the first mixing tank 50 and the second mixing tank 60, respectively. The cleaning solution supply pipes 70 connected to the first mixing tank 50 and the second mixing tank 60 may be combined into one pipe. The cleaning solution supply pipe 70 combined as one may be connected to the cleaning solution supply unit 80. Cleaning liquid supply valves 71 and 72 may be provided on each of the cleaning liquid supply pipes 70. The cleaning liquid in each of the mixing tanks 50 and 60 may be opened and closed by opening and closing the cleaning liquid supply valves 71 and 72. ) Or can be cut off. Each of the cleaning liquid supply valves 71 and 72 may be opened and closed alternately. That is, when the cleaning liquid supply valve 71 of the first mixing tank 50 is opened, the cleaning liquid supply valve 72 of the second mixing tank 60 is blocked and the cleaning liquid supply valve 72 of the second mixing tank 60 is blocked. ) Is opened, the first cleaning liquid supply valve 71 may be blocked.

The cleaning liquid supply unit 80 serves to supply the cleaning liquid supplied from the first mixing tank 50 or the second mixing tank 60 to the nozzle 90. To this end, the cleaning solution supply unit 80 may include a pump 81, a filter 82, and an IPA densitometer 83.

The pump 81 is connected to the first mixing tank 50 and the second mixing tank 60 through the cleaning liquid supply pipe 70. The pump 81 pumps the cleaning liquid in the mixing tank and provides it to the filter 82.

The filter 82 purifies the cleaning liquid moved by the pump 81. That is, the filter 82 filters out the impurities mixed in the cleaning liquid so that the cleaning liquid can be used for as long as possible.

The IPA densitometer 83 is connected to the filter 82 and checks the IPA concentration in the cleaning liquid. Since IPA is a volatile substance, the concentration of IPA in the cleaning liquid may change during the use of the cleaning liquid. Therefore, the IPA concentration meter 83 is used to check whether the IPA concentration in the cleaning liquid is at an appropriate level, and if the IPA concentration in the cleaning liquid is lower than the specified level, the IPA supply valve 21 is adjusted to additionally supply the IPA to the mixing tank. So that the concentration of IPA in the cleaning liquid is maintained at an appropriate level.

The nozzle 90 is for discharging the cleaning liquid supplied from the cleaning liquid supply unit 80 onto the wafer, and may be provided with at least one.

In the above-described example, the case where the cleaning liquid mixing device includes two mixing tanks 50 and 60 has been described as an example. However, the present invention is not limited thereto, and as shown in FIG. 2, the present invention may also be applied to a cleaning liquid mixing device including one mixing tank 60, and the cleaning liquid including two or more mixing tanks is not illustrated. It can also be applied to mixing devices.

Although embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains have various permutations and modifications without departing from the spirit and essential features of the present invention. It is to be understood that the present invention may be practiced in other specific forms, since modifications may be made. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is shown by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

2 is a view schematically showing the configuration of a cleaning liquid mixing device according to another embodiment of the present invention.

10: nitrogen gas supply piping 11: nitrogen gas supply valve

20: IPA supply piping 21: IPA supply valve

50: first mixing tank 51, 61: level sensor

52, 62: bubble generator 60: second mixing tank

70: cleaning liquid supply pipe 71, 72: cleaning liquid supply valve

80: cleaning liquid supply part 81: pump

82: filter 83: IPA densitometer

90: nozzle

Claims

Mixing tank for storing the IPA and ultrapure water supplied through a separate pipe from the outside; And

And a bubble generator for injecting nitrogen gas supplied from the outside into the mixing tank to generate bubbles, thereby allowing the bubble to smoothly mix the IPA and the ultrapure water in the mixing tank.

According to claim 1,

The bubble generator is located under the mixing tank, the bubble generator is connected to the nitrogen gas supply pipe to which the nitrogen gas is supplied, cleaning liquid mixing apparatus.

The method of claim 2,

And a nitrogen gas supply valve positioned in the nitrogen gas supply pipe and configured to adjust an amount of nitrogen gas supplied into the mixing tank.

According to claim 1,

And a cleaning liquid supply unit configured to receive the cleaning liquid mixed with the IPA and the ultrapure water through a cleaning liquid supply pipe connected to the mixing tank and provide the cleaning liquid to a nozzle.