KR20030091427A - Wafer cooling system of semiconductor device manufacturing equipment - Google Patents

Abstract

PURPOSE: A wafer cooling system of a semiconductor device manufacturing equipment is provided to be capable of reducing process time by swiftly exhausting the coolant supplied for cooling a wafer by using a manifold. CONSTITUTION: A wafer cooling system(30) of a semiconductor device manufacturing equipment is provided with a supply line(14) for supplying a coolant from a coolant supply part to the back side of a wafer(W) loaded in a process chamber(12), an exhaust line(32) branched from the supply line and connected to a vacuum pump, and a pressure control valve(24) connected through the exhaust line for controlling the exhaust volume of the coolant according to a control signal. The wafer cooling system further includes a manifold(34) branched from the first exhaust line located at the front portion of the pressure control valve and connected through the second exhaust line located at the rear portion of the pressure control valve, and a plurality of electronic control valve(18a,18b,36) for selectively switching the manifold.

Description

Wafer cooling system of semiconductor device manufacturing equipment

The present invention relates to a wafer cooling system of a semiconductor device manufacturing apparatus, and more particularly, to a wafer cooling system of a semiconductor device manufacturing apparatus for maintaining a temperature of a wafer in a heated atmosphere at a constant level during a process execution process.

In general, high-tech products such as semiconductor devices are manufactured in a production environment that satisfies specific conditions in order to improve their performance and manufacturing yield in accordance with the trend of ultra-precision, high purity, and asepticization. Is one of the major factors affecting process uniformity, critical dimension, profile and repeatability.

In particular, the inside of the process chamber where etching, metal deposition, low pressure chemical vapor deposition, etc. using high frequency power are performed to form a heated atmosphere under the influence of high frequency power, and when the wafer is heated above a predetermined temperature in such an atmosphere, Certain portions of the sensitively acting wafer lead to process failures such as burning or unstable processes.

Accordingly, the process chamber is provided with a cooling system for maintaining the wafer in a temperature range of a predetermined range, where the refrigerant is supplied at a constant pressure to the bottom surface of the wafer seated and supported inside the process chamber to which high frequency power is applied among various cooling systems. The prior art of the configuration to be described with reference to the accompanying drawings.

Looking at the configuration of the cooling system 10 according to the prior art, as shown in Figure 1, the flow rate for adjusting the flow amount of the refrigerant on the supply line 14 from the refrigerant source (not shown) to the process chamber 12 The controller 16, an electronic control valve 18a for selectively blocking the flow of the refrigerant, and a pressure gauge 20 for measuring the pressure state in the supply line 14 leading to the process chamber 12 are sequentially installed. The above-described electronic control valve 18a opens and closes the supply line 14 by the control of a controller (omitted for simplicity of the drawing) according to the process situation in the process chamber 12, and the flow controller 16 is a pressure gauge. The flow rate of the refrigerant is regulated by the control of the controller which receives the pressure state signal measured from 20 and makes the pressure in a certain range. On the other hand, on the supply line 14 between the above-described electronic control valve 18a and the pressure gauge 20, the discharge line 22 which leads to a vacuum pump (not shown) forcibly inducing and discharging the refrigerant is branched and connected On the discharge line 22, the controller controls the controller for forming the pressure change of the supply line 14 measured from the pressure gauge 20 and the electronic control valve 18b controlled by the controller again. The pressure regulating valve 24 for controlling the discharge of the refrigerant by each is installed sequentially.

According to the configuration of the cooling system 10, first, when the wafer W is seated and fixed in the fixing chamber such as an electrostatic chuck in the process chamber 12, the controller that determines the controller controls and supplies the respective electronic control valves 18a and 18b. The line 14 and the discharge line 22 are opened, and at this time, the controller receives the pressure state signal on the supply line 14 according to the refrigerant supply from the pressure gauge 20 so that the pressure according to the refrigerant supply is at a set level. One flow controller 16 and pressure regulating valve 24 are controlled. Here, the set pressure according to the coolant supply described above is used to maintain the wafer W at an appropriate temperature state and to lift the wafer W from the fixing means with respect to the inside of the process chamber 12 at a higher vacuum pressure. It is intended to be within a range that does not. Therefore, the discharge of the refrigerant through the pressure regulating valve 24 is performed in conjunction with the continuous supply of the refrigerant.

When the process is completed by the above-described process, the controller controls the electronic control valve 18a on the supply line 14 to block the supply of the refrigerant, and the wafer (relatively) on the electronic control valve 18a on the supply line 14. W) The refrigerant existing on the supply line 14 reaching the bottom surface is discharged by continuously opening the electronic control valve 18b on the discharge line 22 so as not to enter the process chamber 12.

However, as described above, the wafer W in which the process is completed has a relationship to be continuously fixed to the fixing means until the discharge of the refrigerant on the supply line 14, wherein the discharge of the refrigerant is on the supply line 14. It takes a lot of time by passing through the pressure control valve 24 to induce a small amount of refrigerant in order to control the refrigerant pressure, which results in a delay of the process time for one wafer (W).

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems according to the prior art described above, and to shorten the ejection time of the wafer, that is, the processing time, by allowing the refrigerant supplied to cool the wafer to be discharged more quickly after the process is completed. The present invention provides a wafer cooling system for a semiconductor device manufacturing facility.

1 is a refrigerant supply circuit diagram schematically showing a part of the configuration of the cooling system according to the prior art and the flow relationship of the refrigerant by these configurations.

2 is a refrigerant supply circuit diagram schematically showing some components of a cooling system according to the present invention and a flow relationship of a refrigerant according to these components.

Explanation of symbols on the main parts of the drawings

10, 30: cooling system 12: process chamber

14: Supply Line 16: Flow Controller

18a, 18b, 36: solenoid valve 20: pressure gauge

22, 32: discharge line 24: pressure control valve

34: branch pipe

A characteristic configuration of the present invention for achieving the above object is a supply line for forming a refrigerant supply passage from the refrigerant supply source to the bottom surface of the wafer in the process chamber; A discharge line branching from the supply line and leading to a vacuum pump; And a pressure control valve installed in communication with the discharge line and configured to control the discharge of the refrigerant according to a control signal applied thereto, wherein the wafer cooling system of the semiconductor device manufacturing facility comprises a pressure control valve branched from a discharge line preceding the pressure control valve. A branch pipe connected to the discharge line at the rear end; And an electronic control valve configured to selectively open and close the branch pipe in accordance with a control signal applied to the branch pipe.

In addition, the electronic control valve is provided on the branch pipe is preferably composed of a solenoid valve.

Hereinafter, a wafer cooling system of a semiconductor device manufacturing apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.

2 is a refrigerant supply circuit diagram schematically showing a part of the cooling system according to the present invention and the flow relationship of the refrigerant according to these configurations, the same reference numerals are assigned to the same parts as in the prior art, and detailed description thereof will be omitted. do.

The configuration of the wafer cooling system 30 of the semiconductor device manufacturing apparatus according to the present invention, as shown in Figure 2, the refrigerant on the supply line 14 leading to the process chamber 12 from the refrigerant source (not shown) The flow controller 16 for adjusting the flow rate, the electronic control valve 18a for selectively blocking the flow of the refrigerant, and the pressure gauge 20 for measuring the pressure state in the supply line 14 leading to the process chamber 12 are sequentially Is installed. The above-described electronic control valve 18a opens and closes the supply line 14 by the control of a controller (omitted for simplicity of the drawing) according to the process situation in the process chamber 12, and the flow controller 16 is a pressure gauge. The flow rate of the refrigerant is regulated by the control of the controller which receives the pressure state signal measured from 20 and makes the pressure in a certain range. On the other hand, on the supply line 14 between the above-described electronic control valve 18a and the pressure gauge 20, a discharge line 32 leading to a vacuum pump (not shown) is branched and connected to forcibly induce and discharge the refrigerant. On the discharge line 32, the controller for controlling the controller for forming the pressure change of the supply line 14 measured from the pressure gauge 20 and the electronic control valve 18b controlled by the controller again. The pressure regulating valve 24 for controlling the discharge of the refrigerant by each is installed sequentially. In addition, on the discharge line 32 described above, one end of the branch pipe 34 is connected in a branched shape at the front end of the pressure control valve 24, and the other end of the branch pipe 34 is the pressure control valve described above. (24) It is connected to the discharge line 32 of the rear end. And, on the branch pipe 34 described above, an electronic control valve 36 for selectively blocking the flow of the refrigerant through the branch pipe 34 by the control of the controller is provided, such an electronic control valve 36 is conventional It is preferable to constitute a solenoid valve.

According to the configuration of the cooling system 30, the controller that determines the state in which the wafer W is seated and fixed in the fixing means such as the electrostatic chuck in the process chamber 12, the electronic control valve 36 on the branch pipe (34) In the state of controlling and blocking the flow of the fluid through the branch pipe 34, the electronic control valve 18a installed on the supply line 14 is first opened, and then the electronic control valve 18b installed on the discharge line is opened. Open. Accordingly, the refrigerant supplied from the refrigerant source is filled in the supply line 14 leading to the bottom surface of the wafer (W). At this time, the controller receives the measurement signal of the pressure gauge 20 to check the supply pressure of the refrigerant to the bottom surface of the wafer W, and controls the flow controller 16 based on this to adjust the refrigerant supply amount and at the same time the pressure regulating valve. By controlling the amount of refrigerant discharged by the control of 24, the supply pressure of the refrigerant to the bottom surface of the wafer W is maintained at a constant level.

Then, when the process is completed, the controller cuts off the refrigerant supply through the electronic control valve 18a on the supply line 14 and simultaneously opens the electronic control valve 36 on the branch pipe 34 to supply the supply line 14. The refrigerant already supplied from the electronic control valve 18a on the wafer to the bottom of the wafer W is induced and discharged through the branch pipe 34.

Accordingly, the refrigerant already supplied after the completion of the process flows a large amount of refrigerant through the branch pipe 34 at a high speed in comparison with the conventional art in which a small amount of the refrigerant is discharged at a low speed through the pressure regulating valve 24. The finished wafer W can be separated from the fixing means in a short time, and thus the processing time for one wafer W is shortened.

Therefore, according to the present invention, the ejection time of the wafer, that is, the processing time for one wafer, can be shortened by quickly discharging the refrigerant supplied to cool the wafer after the process is completed by opening the branch pipe. have.

Although the present invention has been described in detail only with respect to specific embodiments, it will be apparent to those skilled in the art that modifications and variations can be made within the scope of the technical idea of the present invention, and such modifications or changes belong to the claims of the present invention. something to do.

Claims (2)

A supply line constituting a refrigerant supply passage from the refrigerant supply source to the bottom of the wafer in the process chamber; A discharge line branching from the supply line and leading to a vacuum pump; In the wafer cooling system of the semiconductor device manufacturing equipment consisting of a pressure regulating valve for controlling the discharge of refrigerant in accordance with a control signal applied in communication with the discharge line, A branch pipe branched from a discharge line in front of the pressure control valve and connected to a discharge line at a rear end of the pressure control valve; And an electronic control valve for selectively opening and closing the branch pipe in accordance with a control signal applied to and communicated with the branch pipe. The method of claim 1, The electronic control valve installed on the branch pipe is a wafer cooling system of the semiconductor device manufacturing equipment, characterized in that the solenoid valve.