Substrate supporting plate

Abstract

A supporting plate having a diameter identical to or larger than a diameter of a substrate to which the supporting plate is attached. A plurality of penetrating holes is provided in a thickness direction of the supporting plate so as to allow a solvent, such as alcohol, to pass therethrough. A diameter of the penetrating holes is approximately in a range of 0.3-0.5 mm, and a pitch of the penetrating holes is approximately in a range of 0.5-1.0 mm. The supporting plate comprises a low thermal expansion material—such as glass, ceramic or an alloy of nickel and iron—which has a thermal expansion coefficient less than that of the substrate.

1 . A supporting plate having a diameter identical to or larger than a diameter of a substrate to which the supporting plate is attached, 
 wherein a plurality of penetrating holes are provided in a thickness direction of the supporting plate so as to allow a solvent to pass therethrough,    wherein a diameter of the penetrating holes is 0.3-0.5 mm, and a pitch of the penetrating holes is 0.5-1.0 mm; and    wherein the supporting plate comprises a low thermal expansion material having a thermal expansion coefficient of 1.5×10 −6  or less.    
     
     
         2 . The supporting plate according to  claim 1 , wherein a diameter of the supporting plate is larger than that of the substrate, and an outer peripheral portion of the supporting plate, which is outside from an area covered by the edge portion of the substrate, is a flat portion in which no penetrating hole is formed.  
     
     
         3 . The supporting plate according to  claim 1 , wherein the supporting plate comprises an alloy of Ni and Fe.  
     
     
         4 . The supporting plate according to  claim 1 , wherein the supporting plate comprises glass.  
     
     
         5 . The supporting plate according to  claim 1 , wherein the supporting plate comprises ceramic.  
     
     
         6 . The supporting plate according to  claim 3 , wherein said alloy includes about 36% of said nickel.  
     
     
         7 . The supporting plate according to  claim 1 , wherein a diameter of the supporting plate is identical as that of the substrate, and an outer peripheral portion of the supporting plate includes the penetrating holes formed therein.  
     
     
         8 . The supporting plate according to  claim 1 , wherein the thickness of said supporting plate is approximately 0.5 mm.  
     
     
         9 . A supporting plate having a diameter identical to or larger than a diameter of a substrate to which the supporting plate is attached, 
 wherein a plurality of penetrating holes are provided in the thickness direction of the supporting plate so as to allow a solvent to pass therethrough; and    wherein the supporting plate comprises a low thermal expansion material having a thermal expansion coefficient of 1.5×10 −6  or less.    
     
     
         10 . The supporting plate according to  claim 9 , wherein the diameter of the penetrating holes is 0.3-0.5 mm, and a pitch of the penetrating holes is 0.5-1.0 mm.  
     
     
         11 . The supporting plate according to  claim 9 , wherein a diameter of the supporting plate is larger than that of the substrate, and an outer peripheral portion of the supporting plate, which is outside from an area covered by the edge portion of the substrate, is a flat portion in which no penetrating hole is formed.  
     
     
         12 . The supporting plate according to  claim 9 , wherein the supporting plate comprises an alloy of Ni and Fe.  
     
     
         13 . The supporting plate according to  claim 9 , wherein the supporting plate comprises glass.  
     
     
         14 . The supporting plate according to  claim 9 , wherein the supporting plate comprises ceramic.  
     
     
         15 . The supporting plate according to  claim 9 , wherein a thickness of said supporting plate is approximately 0.5 mm.  
     
     
         16 . A supporting plate having a diameter identical to or larger than the diameter of a substrate to which the supporting plate is attached, 
 wherein a plurality of penetrating holes are provided in the thickness direction of the supporting plate so as to allow a solvent to pass therethrough; and    wherein a thermal expansion coefficient of the supporting plate is less than that of the substrate.    
     
     
         17 . The supporting plate according to  claim 16 , wherein said thermal expansion coefficients of said supporting plate and said substrate are about 1.5×10 −6  or less and 4×10 −6  or less, respectively.  
     
     
         18 . The supporting plate according to  claim 16 , the supporting plate is formed of material comprising one of an alloy of Ni and Fe, ceramic and glass.  
     
     
         19 . The supporting plate according to  claim 16 , wherein a diameter of the supporting plate is larger than that of the substrate, and an outer peripheral portion of the supporting plate, which is outside from an area covered by the edge portion of the substrate, is a flat portion in which no penetrating hole is formed.  
     
     
         20 . The supporting plate according to  claim 16 , wherein the diameter of the penetrating holes is in a range of 0.3-0.5 mm, and a pitch of the penetrating holes is in a range of 0.5-1.0 mm.