Etching apparatus

Abstract

In order to prevent a workpiece from being damaged in etching workpiece of various external diameters, a ceramic holding jig corresponding to the external diameter of workpiece is mounted on a chuck table in a chamber of an etching apparatus. The chuck table is composed of a holding face for holding a workpiece and for converting etching gas into plasma and insulating zones each having an internal diameter smaller than the external diameter of the workpiece and an external diameter larger than the external diameter of the workpiece. In case a workpiece is to be held by either a first ceramic holding jig or a second ceramic holding jig on the chuck table, a jig identifying means installed to the chamber identify in advance which ceramic holding jig is mounted on the chuck table to match the holding jig and the workpiece each other, thereby to prevent the workpiece from being damaged.

1 . An etching apparatus comprising: a chuck table for holding a workpiece; etching gas supply means for supplying an etching gas to the workpiece held by said chuck table; a chamber housing said chuck table and said etching gas supply means and having an opening, through which said workpiece is delivered in and out; transfer means for delivering the workpiece into and out of said chamber through said opening; and a shutter for bringing said opening into an opened state or a closed state, wherein 
 said chuck table is configured to include a holding face for holding the workpiece and for converting the etching gas into plasma, and insulating zones each having an internal diameter smaller than the external diameter of the workpiece and an external diameter larger than the external diameter of the workpiece,    said insulating zones respectively match at least two types of workpiece with different external diameters, including a first ring-shaped insulating zone having an internal diameter smaller than the external diameter of a first workpiece with the larger external diameter and an external diameter larger than the external diameter of said first workpiece; and a second ring-shaped insulating zone having an internal diameter smaller than the external diameter of the second workpiece with external diameter smaller than said first workpiece, and an external diameter larger than the external diameter of said second workpiece, and    said chuck table can mount a first ceramic holding jig for housing said first workpiece and for covering the portion of said first insulating zone of said chuck table that does not contact said first workpiece; and a second ceramic holding jig for housing said second workpiece and for covering the portion of said second insulating zone of said chuck table that does not contact the second workpiece, and further comprising:    a jig identifying means for identifying said first ceramic holding jig and said second ceramic holding jig.    
   
   
       2 . An etching apparatus according to  claim 1 , wherein the external diameter of said first ceramic holding jig and the external diameter of said second ceramic holding jig are different, and said jig identifying means is arranged on the outer side of the chamber for measuring the external diameter of the first ceramic holding jig and the external diameter of the second ceramic holding jig when the opening is brought into the opened state.  
   
   
       3 . An etching apparatus according to  claim 2 , wherein said jig identifying means has a function to output a signal corresponding to an identified result, and decision means for deciding, by inputting the signal, whether or not the ceramic holding jig mounted on the chuck table matches the workpiece to be delivered into the chamber is connected with the jig identifying means, the transfer means is informed of the result of the decision by the decision means, and the transfer means controls the delivery of the workpiece into the chamber on the basis of the result of the decision.  
   
   
       4 . An etching apparatus according to  claim 1 , wherein the workpiece is a semiconductor wafer, whereby the face of the ground semiconductor wafer is thereafter etched in the chamber.  
   
   
       5 . An etching apparatus according to  claim 2 , wherein the workpiece is a semiconductor wafer, whereby the face of the ground semiconductor wafer is thereafter etched in the chamber.  
   
   
       6 . An etching apparatus according to  claim 3 , wherein the workpiece is a semiconductor wafer, whereby the face of the ground semiconductor wafer is thereafter etched in the chamber.