Chiller of etch equipment for semiconductor processing

Abstract

A chiller for etching equipment for processing a semiconductor includes: a chuck for controlling a temperature of a semiconductor wafer, a coolant pipeline connected to the chuck, a coolant tank connected to the coolant pipeline, an evaporator in the coolant tank, a refrigerant in the evaporator, a compressor for compressing refrigerant flowing from the evaporator, a condenser for condensing the compressed refrigerant from the compressor, and an electronically controlled expansion valve connected to the condenser to receive compressed refrigerant, and connected to the evaporator for feeding the expanded refrigerant into evaporator.

1 . An apparatus comprising:
 a chuck for controlling a temperature of a semiconductor wafer;   a coolant pipeline connected to the chuck;   a coolant tank connected to the coolant pipeline;   an evaporator in the coolant tank;   a refrigerant in the evaporator;   a compressor for compressing refrigerant flowing from the evaporator;   a condenser for condensing the compressed refrigerant from the compressor; and   an electronically controlled expansion valve connected to the condenser to receive compressed refrigerant, and connected to the evaporator for feeding expanded refrigerant into evaporator.   
   
   
       2 . The apparatus of  claim 1 , wherein a refrigerant circulation flow path is defined by the condenser, the expansion valve, the evaporator, the compressor, and connections therebetween, and wherein a degree of opening of the expansion valve is controlled with dependence on at least one of a temperature and a pressure of the refrigerant in at least one position in the refrigerant circulation flow path. 
   
   
       3 . The apparatus of  claim 2 , wherein the degree of opening of the expansion valve is controlled based on a difference in temperatures between refrigerant which flows from the condenser and refrigerant which flows from the evaporator tank into compressor. 
   
   
       4 . The apparatus of  claim 2 , wherein the degree of opening of the expansion valve is controlled based on a pressure of the refrigerant flowing from the evaporator to the compressor. 
   
   
       5 . The apparatus of  claim 2 , wherein the degree of opening of the expansion valve is controlled by proportional integral differential control. 
   
   
       6 . The apparatus of  claim 5 , wherein the expansion valve receives digitized electrical signals as input data. 
   
   
       7 . The apparatus of  claim 6 , wherein the degree of opening of the expansion valve is varied from stage zero to stage N by a stepper motor, where N is a positive real number. 
   
   
       8 . The apparatus of  claim 1 , wherein a degree of opening of the expansion valve is controlled based on a temperature of the refrigerant in the coolant pipeline. 
   
   
       9 . The apparatus of  claim 2 , wherein a degree of opening of the expansion valve is increased when the temperature of the refrigerant in at least one position in the refrigerant circulation flow path is higher than a set temperature. 
   
   
       10 . The apparatus of  claim 2 , wherein degree of opening of the expansion valve is decreased when the temperature of the refrigerant in at least one position in the refrigerant circulation flow path is lower than a set temperature. 
   
   
       11 . An apparatus comprising:
 a chuck for controlling a temperature of a semiconductor wafer;   a coolant pipeline connected to the chuck;   a coolant tank connected to the coolant pipeline;   a coolant circulation flow path including the coolant tank connected to the coolant pipeline and a circulation pump;   a refrigerant circulation flow path including a condenser, an expansion valve, a refrigerant path in an evaporator fixed in the coolant tank, and a compressor; and   an automatic valve for hot gas fixed in the coolant tank.   
   
   
       12 . The apparatus of  claim 11 , wherein the automatic valve for hot gas is driven by a stepper motor. 
   
   
       13 . The apparatus of  claim 12 , wherein the stepper motor receives digitized electrical signals as input data. 
   
   
       14 . The apparatus of  claim 13 , wherein the degree of opening of the automatic valve is varied from stage zero to stage N by the stepper motor, where N is a positive real number. 
   
   
       15 . An method comprising:
 providing a semiconductor wafer;   mounting the semiconductor wafer on a chuck;.   controlling the temperature of the wafer by circulating coolant from a coolant tank through a coolant pipeline connected to the chuck;   circulating a refrigerant in an evaporator in the coolant tank to form evaporated refrigerant;   compressing the evaporated refrigerant flowing from the evaporator to form compressed refrigerant;   condensing the compressed refrigerant to form condensed refrigerant; and   expanding the condensed refrigerant using an electronically controlled expansion valve; and   feeding the expanded refrigerant into evaporator.   
   
   
       16 . The method of  claim 15 , wherein a degree of opening of the expansion valve is controlled with dependence on at least one of a temperature and a pressure of one of the evaporated refrigerant, the compressed refrigerant, the condensed refrigerant, or the expanded refrigerant. 
   
   
       17 . The method of  claim 16 , wherein the degree of opening of the expansion valve is controlled based on a difference in temperatures between the condensed refrigerant and the evaporated refrigerant. 
   
   
       18 . The method of  claim 16 , wherein the degree of opening of the expansion valve is controlled based on a pressure of the evaporated refrigerant. 
   
   
       19 . The method of  claim 16 , wherein the degree of opening of the expansion valve is controlled by proportional integral differential control. 
   
   
       20 . The method of  claim 15 , wherein the expansion valve receives digitized electrical signals as input data.