Wafer processing apparatus capable of controlling wafer temperature

Abstract

In a wafer processing apparatus, wafers are sequentially placed one by one on a ceramic plate of a wafer stage within a vacuum chamber. The pressure of a heat-conductive gas introduced at this time between the wafer and the ceramic plate is adjusted to control the temperature of the wafer, and the wafer is processed by use of plasma. In this case, the user can select any one of a process for regulating the pressure of the heat-conductive gas each time the wafers are sequentially placed on the wafer stage, a process for optimizing aging conditions, and a process for optimizing heater conditions so that the wafer temperature variation within lot can be reduced by performing the selected process. The selected process is performed on the basis of its conditions that are computed to determine by a control-purpose computer of the processing apparatus.

1 . A wafer processing apparatus in which a plurality of semiconductor wafers are sequentially placed on a wafer stage and processed by use of plasma, said apparatus comprising: 
 means for measuring the temperature of said wafer stage; and    means for adjusting pressure of a heat-conductive gas introduced between each of said semiconductor wafers and said wafer stage on a basis of said wafer stage temperature measured by said temperature measuring means each time said wafers are sequentially placed on said wafer stage.    
   
   
       2 . A wafer processing apparatus according to  claim 1 , wherein said temperature measuring means is any one of a sheathed thermocouple, a fluorescent temperature gauge and a thermistor.  
   
   
       3 . A wafer processing apparatus in which a plurality of semiconductor wafers are sequentially placed on a wafer stage and processed by use of plasma, said apparatus comprising: 
 means for cooling said wafer stage by a refrigerant of which temperature is regulated by a temperature controller;    means for measuring temperature of said wafer stage; and    means for adjusting temperature of said refrigerant on a basis of said wafer stage temperature measured by said temperature measuring means each time said wafers are sequentially placed on said wafer stage.    
   
   
       4 . A wafer processing apparatus according to  claim 3 , wherein said temperature measuring means is any one of a sheathed thermocouple, a fluorescent temperature gauge and a thermistor.  
   
   
       5 . A wafer processing apparatus in which a plurality of semiconductor wafers are sequentially placed on a wafer stage and processed by use of plasma, said apparatus comprising: 
 means for heating said wafer stage and measuring the temperature of said wafer stage; and    means for adjusting at least one of a pressure of a heat-conductive gas introduced between each of said semiconductor wafers and said wafer stage and all electric power supplied to said heater on a basis of said wafer stage temperature measured by said temperature measuring means each time said wafers are sequentially placed on said wafer stage.    
   
   
       6 . A wafer processing apparatus according to  claim 5 , wherein said temperature measuring means is any one of a sheathed thermocouple, a fluorescent temperature gauge and a thermistor.