Wafer holder, heater unit having the wafer holder, and wafer prober having the heater unit

Abstract

A wafer holder less susceptible to deformation even under high load and having high heat-insulating effect and hence capable of improving positional accuracy, improving thermal uniformity and rapid heating and cooling of chips, as well as a heater unit including the wafer holder and a wafer prober including the heater unit are provided. The wafer holder includes a chuck top having a chuck top conductive layer on its surface and a supporter supporting the chuck top, and has a support member in a space between the chuck top and the supporter. Preferably, the support member is arranged concentric with the supporter or approximately at the center of the supporter, and more preferably, support members arranged concentrically and arranged at the center are both provided.

1 . A wafer holder, comprising: a chuck top having a chuck top conductive layer on a surface and a supporter supporting said chuck top, wherein a space is formed between said chuck top and said supporter, and a support member is provided in said space.  
   
   
       2 . The wafer holder according to  claim 1 , wherein 
 said support member is arranged concentric with said supporter.    
   
   
       3 . The wafer holder according to  claim 1 , wherein 
 said support member is arranged approximately at the center of said supporter.    
   
   
       4 . The wafer holder according to  claim 1 , comprising 
 said support member arranged concentric with said supporter, and said support member arranged approximately at the center of said supporter.    
   
   
       5 . The wafer holder according to  claim 1 , wherein 
 said support member has a pipe-shape.    
   
   
       6 . The wafer holder according to  claim 1 , wherein 
 thermal expansion coefficient of said support member and thermal expansion coefficient of said supporter are approximately the same.    
   
   
       7 . The wafer holder according to  claim 1 , wherein 
 said support member has Young's modulus of at least 100 GPa.    
   
   
       8 . A heater unit comprising the wafer holder according to  claim 1 .  
   
   
       9 . A wafer prober comprising the heater unit according to  claim 8 .  
   
   
       10 . A wafer holder, comprising: a chuck top for mounting a wafer and a supporter supporting said chuck top, wherein a space is formed between said chuck top and said supporter, and a material of low thermal conductivity having thermal conductivity lower than that of said chuck top is inserted in said space.  
   
   
       11 . The wafer holder according to  claim 10 , wherein 
 thermal conductivity of said material of low thermal conductivity is lower than thermal conductivity of said supporter.    
   
   
       12 . The wafer holder according to  claim 10 , wherein 
 material of said chuck top is a composite body of metal and ceramics.    
   
   
       13 . The wafer holder according to  claim 12 , wherein 
 material of said chuck top is a composite body of aluminum and silicon carbide or a composite body of silicon and silicon carbide.    
   
   
       14 . The wafer holder according to  claim 10 , wherein 
 material of said chuck top is ceramics.    
   
   
       15 . The wafer holder according to  claim 10 , wherein 
 material of said supporter is ceramics or a composite body of a plurality of ceramics.    
   
   
       16 . The wafer holder according to  claim 10 , wherein 
 main component of the material of said supporter is any of mullite, alumina, a composite body of mullite and alumina, aluminum nitride, and silicon nitride.    
   
   
       17 . A heater unit comprising the wafer holder according to  claim 10 .  
   
   
       18 . A wafer prober comprising the heater unit according to  claim 17.