Ceramic substrate for semiconductor manufacture/inspection apparatus, ceramic heater, electrostatic clampless holder, and substrate for wafer prober

Abstract

The present invention provide a ceramic substrate for semiconductor manufacture and/or inspection which is conducive to decrease in α-rays radiated, and change of thermal conductivity with passage of the time, and which is superior in the temperature controllability. This invention is related to a ceramic substrate for apparatuses for use in semiconductor manufacture and/or inspection, wherein the level of α-rays radiated from said ceramic substrate exceeds 0.25 c/cm 2 ·hr and is not higher than 50 c/cm 2 ·hr.

1 . A ceramic substrate for apparatuses for use in semiconductor manufacture/inspection, 
 wherein the level of α-rays radiated from said ceramic substrate exceeds 0.25 c/cm 2 ·hr and is not higher than 50 c/cm 2 ·hr.    
   
   
       2 . The ceramic substrate according to  claim 1 , 
 wherein said ceramic substrate has a temperature adjusting means.    
   
   
       3 . A ceramic heater for heating a semiconductor comprising: 
 a ceramic substrate, and a heating element disposed on the surface of the ceramic substrate or inside the ceramic substrate,    wherein the level of α-rays radiated from said ceramic substrate exceeds 0.25 c/cm 2 ·hr and is not higher than 50 c/cm 2 ·hr.    
   
   
       4 . An electrostatic chuck comprising a ceramic substrate and electrodes embedded therein, 
 wherein the level of α-rays radiated from said ceramic substrate exceeds 0.25 c/cm 2 ·hr and is not higher than 50 c/cm 2 ·hr.    
   
   
       5 . The electrostatic chuck according to  claim 4 , 
 wherein said ceramic substrate has a temperature adjusting means.    
   
   
       6 . A substrate for a wafer prober comprising a ceramic substrate and a conductor layer formed on the surface thereof, 
 wherein the level of α-rays radiated from the surface of said ceramic substrate exceeds 0.25 c/cm 2 ·hr and is not higher than 50 c/cm 2 ·hr.    
   
   
       7 . The substrate for a wafer prober according to  claim 6 , 
 wherein said ceramic substrate has a temperature adjusting means.