Floating pin for substrate transfer

Abstract

A floating pin for positioning a substrate relative to a substrate support includes a shaft configured to move through a guide hole in a substrate support, and a pin head including a top surface and a flat shoulder surface disposed between the top surface and the shaft. The flat shoulder surface is configured to be seated on a recessed surface of the substrate support and seal the guide hole of the substrate support.

What is claimed is: 
     
         1 . A floating pin for positioning a substrate relative to a substrate support, the floating pin comprising:
 a shaft configured to move through a guide hole in a substrate support; and   a pin head comprising a top surface and a flat shoulder surface disposed between the top surface and the shaft,   wherein the flat shoulder surface is configured to be seated on a recessed surface of the substrate support and seal the guide hole of the substrate support.   
     
     
         2 . The floating pin of  claim 1 , wherein:
 the flat shoulder surface has a diameter of between 8.9 mm and 9.1 mm, and   the shaft has a diameter of between 3.225 mm and 3.285 mm, having a clearance to interior sidewall surface of the guide hole of between 0.3 mm and 0.4 mm.   
     
     
         3 . The floating pin of  claim 1 , wherein the pin head comprises:
 a shoulder portion that includes the flat shoulder surface; and   a countersunk portion that includes the top surface having a larger diameter than the flat shoulder surface, the countersunk portion having a beveled surface extending from an exterior sidewall surface of the shoulder portion to the top surface.   
     
     
         4 . The floating pin of  claim 3 , wherein:
 the flat shoulder surface has a diameter of between 8.9 mm and 9.1 mm,   the top surface has a diameter of between 11.1 mm and 11.2 mm, and   the shaft has a diameter of between 3.225 mm and 3.285 mm, having a clearance to interior sidewall surface of the guide hole of between 0.3 mm and 0.4 mm.   
     
     
         5 . The floating pin of  claim 1 , wherein the shaft comprises aluminum oxide. 
     
     
         6 . The floating pin of  claim 1 , further comprising:
 a dead weight disposed at an end of the shaft opposite the pin head.   
     
     
         7 . The floating pin of  claim 6 , wherein the dead weight comprises stainless steel and weighs between 13 g and 20 g. 
     
     
         8 . A lift pin assembly for positioning a substrate relative to a substrate support, the lift pin assembly comprising:
 a floating pin having a pin head and a shaft; and   a lift pin configured to contact an end of the shaft opposite the pin head and move the shaft through a guide hole in the substrate support, wherein:
 the pin head comprises a top surface and a flat shoulder surface disposed between the top surface and the shaft, and 
 the flat shoulder surface is configured to be seated on a recessed surface of the substrate support and seal the guide hole of the substrate support. 
   
     
     
         9 . The lift pin assembly of  claim 8 , wherein:
 the flat shoulder surface has a diameter of between 8.9 mm and 9.1 mm, and   the shaft has a diameter of between 3.225 mm and 3.285 mm, having a clearance to interior sidewall surface of the guide hole of between 0.3 mm and 0.4 mm.   
     
     
         10 . The lift pin assembly of  claim 8 , wherein the pin head comprises:
 a shoulder portion that includes the flat shoulder surface; and   a countersunk portion that includes the top surface having a larger diameter than the flat shoulder surface, the countersunk portion having a beveled surface extending from an exterior sidewall surface of the shoulder portion to the top surface.   
     
     
         11 . The lift pin assembly of  claim 10  wherein:
 the flat shoulder surface has a diameter of between 8.9 mm and 9.1 mm, 
 the top surface has a diameter of between 11.1 mm and 11.2 mm, and 
 the shaft has a diameter of between 3.225 mm and 3.285 mm, having a clearance to interior sidewall surface of the guide hole of between 0.3 mm and 0.4 mm. 
 
     
     
         12 . The lift pin assembly of  claim 8 , wherein:
 the shaft comprises aluminum oxide, and   the lift pin comprises stainless steel.   
     
     
         13 . The lift pin assembly of  claim 8 , further comprising:
 a dead weight disposed at an end of the shaft opposite the pin head.   
     
     
         14 . The lift pin assembly of  claim 13 , wherein the dead weight comprises stainless steel and weighs between 13 g and 20 g. 
     
     
         15 . A processing system, comprising:
 a substrate support having a guide hole therethrough, the guide hole comprising a seating portion and a guide portion, wherein the seating portion comprises a flat shoulder surface between a front-side surface of the substrate support and the guide portion; and   a lift pin assembly comprising:
 a floating pin having a pin head configured to be seated in the seating portion and a shaft configured to move through the guide portion; and 
 a lift pin configured to contact an end of the shaft opposite the pin head and move the floating pin through the guide hole in the substrate support, wherein: 
   the pin head comprises a top surface and a flat shoulder surface disposed between the top surface and the shaft, and   the flat shoulder surface of the pin head is configured to be seated on the flat shoulder surface of the seating portion and seal the guide hole of the substrate support.   
     
     
         16 . The processing system of  claim 15 , wherein:
 the flat shoulder surface of the pin head has a diameter of between 8.9 mm and 9.1 mm,   the shaft has a diameter of between 3.225 mm and 3.285 mm,   the flat shoulder surface of the seating portion has a diameter of between 10.6 mm and 10.8 mm, and   the guide portion has a diameter of between about 3.95 mm and about 4.05 mm.   
     
     
         17 . The processing system of  claim 15 , wherein the pin head comprises:
 a shoulder portion that includes the flat shoulder surface; and   a countersunk portion that includes the top surface having a larger diameter than the flat shoulder surface, the countersunk portion having a beveled surface extending from an exterior sidewall surface of the shoulder portion to the top surface.   
     
     
         18 . The processing system of  claim 17 , wherein:
 the flat shoulder surface has a diameter of between 8.9 mm and 9.1 mm,   the top surface has a diameter of between 11.1 mm and 11.2 mm,   the shaft has a diameter of between 3.225 mm and 3.285 mm, having a clearance to interior sidewall surface of the guide hole of between 0.3 mm and 0.4 mm,   the flat shoulder surface of the seating portion has a diameter of between 12.6 mm and 12.8 mm, and   the guide portion has a diameter of between about 3.95 mm and about 4.05 mm.   
     
     
         19 . The processing system of  claim 15 , wherein:
 the shaft comprises aluminum oxide, and   the lift pin comprises stainless steel.   
     
     
         20 . The processing system of  claim 15 , further comprising:
 a dead weight disposed at an end of the shaft opposite the pin head, wherein the dead weight comprises stainless steel and weighs between 13 g and 20 g.