JPH11353032A - Mechanism and method for detecting leakage of cooling gas - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the leakage of cooling gas by quantitatively monitoring whether the quantity of sealed gas is regulated within a fixed range or not. SOLUTION: The cooling gas is led into the backside of a substrate 13 to be treated in a process chamber. A pressure controller 5 controls a control valve 3 so as to keep the quantity of introduced gas within the fixed range. Then the inputs of a pressure gauge 4 attached on the same side as the control valve 3 and a pressure gauge 10 attached on the opposite side of the control valve are fetched into an ordinary monitor mechanism 12, the difference of signals between the inputs of the pressure gauges 4 and 10 is operated and when it exceeds the allowable range, abnormality is reported by judging the existence of the leakage of cooling gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a liquid crystal panel manufacturing,
The present invention is applied to an apparatus having a form in which a substrate or a wafer is transferred to a process chamber in the apparatus, such as a semiconductor manufacturing apparatus, and relates to a leak detection mechanism and a detection method of a cooling gas of a substrate backside cooling method in the process chamber. .

[0002]

2. Description of the Related Art FIG. 2 is an explanatory view showing the structure of a conventional cooling gas leak detecting mechanism. Reference numeral 15 denotes a clamp mechanism for holding a substrate, 16 denotes a gas flow controller for cooling a substrate, and 17 denotes a pressure. A control valve for controlling, 18 is a pressure gauge for monitoring the pressure of the cooling gas, 19 is
A pressure controller which takes in a signal from the pressure gauge 18 and calculates a difference from a set pressure to issue an opening command to the control valve 17; 20 is an isolation valve for keeping the pressure gauge 18 in a vacuum state; A stop valve for turning on and off the cooling gas, a main valve 22 mounted on the upstream side of the control valve 17, a bypass valve 23 for quickly exhausting gas at the end of cooling,
24 is a substrate to be processed.

In the mechanism configured as described above, the relationship and operation of each component will be described below.

First, in a process chamber A, a substrate 2
4 is held down by the clamp mechanism 15. Then, the control valve 17, the main valve 22, and the stop valve 21
And the isolation valve 20 is opened. Further, a cooling gas flow command is given to the gas flow controller 16 to introduce the cooling gas to the back surface of the substrate. At this time, in order to keep the introduced gas amount constant, the exhaust amount is calculated from the input value of the pressure gauge 18 attached to the gas pipe, and the control valve 17 installed to adjust the gas exhaust amount is adjusted. The opening command is adjusted to keep the amount of introduced gas within a certain range.

[0005]

However, when the pressure of the cooling gas is controlled by the above-described cooling gas leak detection mechanism, when a small amount of cooling gas leaks into the process chamber from the back surface of the substrate, The cooling gas cannot be adjusted to a pressure within a certain range unless an amount of gas that compensates for the leaking amount is contained. Therefore, although the gas pressure is within a certain range, the amount of gas introduced is not constant. In addition, even with a pressure gauge monitoring the pressure in the process chamber, the leak cannot be sufficiently detected, and not only the cooling effect does not become constant, but also the leaked cooling gas affects the process state, thereby There is a problem that a substrate that is not normally processed occurs, which lowers the productivity of the apparatus.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and quantitatively monitors whether or not the amount of the contained gas is adjusted within a predetermined range, and detects a minute leakage of the cooling gas for detecting the presence or absence of an abnormality. It is an object to provide a mechanism and a detection method.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a mechanism for cooling a back surface of a processing substrate in a process chamber by adjusting a flow rate controller of a cooling gas and a pressure of the cooling gas. A first pressure gauge mounted upstream of the control valve for monitoring the pressure of the cooling gas introduced to the back side of the substrate, and taking in a signal from the first pressure gauge. A pressure controller that calculates a difference from a set pressure and feeds back an opening command to the control valve, and a cooling gas that is attached upstream with respect to the process chamber and that is not introduced to the back surface of the substrate. A second pressure gauge for monitoring pressure, a signal from the first pressure gauge and a signal from the second pressure gauge are taken in, a pressure difference between the signals is calculated, and an allowable range is set. It characterized by having a constant monitoring mechanism for notifying an abnormality when was e.

The present invention also provides a cooling gas flow controller, a control valve for adjusting the pressure of the cooling gas, and a control valve for adjusting the pressure of the cooling gas. A pressure gauge attached to the upstream side and monitoring the pressure of the cooling gas introduced to the back surface of the substrate, and taking in a signal from the pressure gauge, calculating a difference from a set pressure, and calculating a difference with the control valve. A pressure controller that feeds back the opening command and the opening command of the control valve are taken in, and the difference between the opening and the set opening is calculated,
It is characterized by having a constant monitoring mechanism for notifying an abnormality when exceeding an allowable range.

The present invention also provides a cooling gas flow controller, a control valve for adjusting the pressure of the cooling gas, a pressure gauge for monitoring the pressure of the cooling gas introduced to the back surface of the substrate, and the pressure gauge. Signal from the
A pressure controller that calculates a difference from a set pressure and feeds back an opening command to the control valve, and a cooling gas in a mechanism for introducing a cooling gas to the back surface of the processing substrate in the process chamber to cool the substrate. The leak detection method of calculating the pressure difference between the pressure of the cooling gas before introducing it to the back surface of the substrate and the pressure of the cooling gas after introducing it to the back surface of the substrate, when exceeding the allowable range It is characterized by notification of abnormality.

The present invention also provides a cooling gas flow controller, a control valve for adjusting the pressure of the cooling gas, and a cooling gas mounted on the upstream side of the control valve and introduced to the back surface of the substrate. A pressure controller that monitors the pressure and calculates the difference from the set pressure, and includes a pressure controller that feeds back the opening command to the control valve, and introduces a cooling gas to the back surface of the processing substrate in the process chamber. A method for detecting a leakage of cooling gas in a cooling mechanism, wherein a difference between an opening command and an opening of the control valve is calculated.
It is characterized in that an abnormality is notified when the value exceeds the allowable range.

By such means, it is possible to monitor the introduction amount of the cooling gas and determine that the leakage of the cooling gas exists when the amount exceeds the allowable range.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is an explanatory view showing the structure of a cooling gas leak detecting mechanism according to the present invention, wherein 1 is a clamp mechanism for holding a substrate, 2 is a gas flow controller for cooling a substrate, and 3 is a pressure controller. Control valve, 4
Is a pressure gauge on the control valve side that monitors the pressure of the cooling gas, 5 is a pressure controller that takes in a signal from the pressure gauge 4, calculates a difference from a set pressure, and issues an opening command to the control valve 3. 6 is an isolation valve for keeping the pressure gauge 4 in a vacuum state, 7 is a stop valve for turning on and off the cooling gas, 8 is a main valve mounted on the upstream side of the control valve 3, and 9 is a gas exhaust at the end of cooling. Bypass valve for quick operation, 10
Is a pressure gauge mounted on the opposite side of the control valve 3, 11 is an isolation valve for keeping the pressure gauge 10 in a vacuum state, 12 is a signal from the pressure gauge 4 and the pressure gauge 10, and calculates a pressure difference therebetween. A constant monitoring mechanism for notifying an abnormality when the value exceeds an allowable range, 13 is a substrate to be processed, and 14 is an opening command from the pressure controller 5 to the control valve 3, and a difference from the opening monitoring value. Is a constant monitoring mechanism for notifying an abnormality when the value exceeds the allowable range.

Next, the operation will be described.

First, in the process chamber A, the substrate 1
3 is held down by the clamp mechanism 1. Then, the control valve 3, the main valve 8 and the stop valve 7 are opened,
A cooling gas setting command is given to the gas flow controller 2 to introduce the cooling gas to the back surface of the substrate. At this time, in order to keep the introduced gas amount constant, the exhaust amount is calculated from the input value of the pressure gauge attached to the gas pipe, and the control valve 3 attached to adjust the gas exhaust amount is opened. Adjust the degree command. Then, the input of the pressure gauge 10 attached to the opposite side of the control valve 3 is always taken into the monitoring mechanism 12, and the difference between the input signal of the pressure gauge 4 and the input signal of the pressure gauge 10 is calculated. I do.

With this configuration, when the difference between the pressure of the cooling gas before the introduction and the pressure of the cooling gas after the introduction with respect to the rear surface of the substrate exceeds an allowable range, it is determined that the leakage of the cooling gas has occurred. can do.

In addition to the cooling gas leak detection method described above, the pressure
Is always taken into the monitoring mechanism 14, a difference from a preset monitoring value of the opening is calculated, and when it exceeds the allowable range, it is determined that the leakage of the cooling gas has occurred, There is a method of notifying abnormalities. It should be noted that 2
It goes without saying that two cooling gas leak detection methods may be used in combination.

[0018]

According to the present invention constructed as described above, it is determined whether or not the amount of cooling gas introduced is within a certain range by the signals of the pressure gauge on the introduction side and the pressure gauge on the discharge side. By calculating the pressure difference, the monitoring mechanism always notifies the abnormality when the pressure difference exceeds the allowable range, the substrate cooling efficiency is kept within a certain range, and by detecting the leakage of the cooling gas,
It is possible to reduce the occurrence of substrates that are not properly processed and improve the productivity of the apparatus.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a cooling gas leak detection mechanism according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a configuration of a conventional cooling gas leak detection mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Clamp mechanism 2 Gas flow controller 3 Control valve 4, 10 Pressure gauge 5 Pressure controller 6, 11 Isolation valve 7 Stop valve 8 Main valve 9 Bypass valve 12, 14 Constant monitoring mechanism 13 Substrate

Claims (4)

[Claims] In a mechanism for cooling a back surface of a substrate for processing in a process chamber, a flow rate controller of a cooling gas, a control valve for adjusting a pressure of the cooling gas, and an upstream side of the control valve. A first pressure gauge for monitoring the pressure of the cooling gas introduced to the back surface of the substrate, and taking in a signal from the first pressure gauge to calculate a difference from a set pressure, A pressure controller that feeds back an opening degree command, a second pressure gauge attached upstream of the process chamber, and monitors a pressure of a cooling gas before being introduced to the back surface of the substrate; and a first pressure gauge. Having a constant monitoring mechanism that captures the signal of the second pressure gauge and calculates the pressure difference and notifies an abnormality when the pressure difference exceeds an allowable range. A leakage detection mechanism for cooling gas. 2. A mechanism for cooling a back surface of a substrate for processing in a process chamber, a flow controller for a cooling gas, a control valve for adjusting a pressure of the cooling gas, and an upstream side with respect to the control valve. And a pressure gauge for monitoring the pressure of the cooling gas introduced to the back surface of the substrate, and a signal from the pressure gauge is taken in, a difference from a set pressure is calculated, and an opening degree command is issued to the control valve. A pressure controller that feeds back the control valve, takes in the opening command of the control valve, calculates the difference between the opening and the set opening, and has a constant monitoring mechanism that notifies an abnormality when the difference exceeds an allowable range. Of leaking cooling gas. 3. A cooling gas flow controller, a control valve for adjusting a pressure of the cooling gas, a pressure gauge for monitoring a pressure of the cooling gas introduced to the back surface of the substrate, and a signal from the pressure gauge. A pressure controller that calculates a difference from a set pressure, feeds back an opening command to the control valve, and cools by introducing a cooling gas to the back surface of the processing substrate in the process chamber. The method for detecting the leakage of the cooling gas in the above, wherein the pressure difference between the pressure of the cooling gas before introduction to the back surface of the substrate and the pressure of the cooling gas after introduction to the back surface of the substrate is calculated, exceeding the allowable range A leakage detection method for a cooling gas, wherein an abnormality is notified when the cooling gas leaks. 4. A controller for controlling the flow rate of the cooling gas, a control valve for adjusting the pressure of the cooling gas, and a control valve mounted on the upstream side of the control valve for controlling the pressure of the cooling gas introduced to the back surface of the substrate. A pressure controller that monitors and calculates a difference from a set pressure and feeds back an opening command to the control valve, and a mechanism that introduces a cooling gas to the back surface of the process substrate in the process chamber and cools the substrate. A cooling gas leakage detection method, wherein a difference between an opening command of the control valve opening command and a setting opening is calculated, and an abnormality is notified when the opening exceeds an allowable range. Leak detection method.