Ceramic substrate

Abstract

The present invention provides a ceramic substrate for use in an apparatus for manufacturing and inspecting semiconductors. The ceramic substrate comprises a through-hole having excellent tolerance performance against a drawing stress applied to an external terminal pin. The through-hole is provided with a projection which protrudes into the ceramic substrate made of aluminum nitride as primary component.

1 . A ceramic substrate comprising: 
 a conductor layer on the surface and/or inside of said ceramic substrate; and    a through-hole connected electrically to said conductor layer, wherein a projection is formed on a side wall of said through-hole so as to protrude into said ceramic substrate.    
   
   
       2 . The ceramic substrate according to  claim 1 , further comprising: 
 a conductor layer on the surface of said ceramic substrate; and    a through-hole connected electrically to said conductor layer, wherein a projection is formed on a side wall of said through-hole so as to protrude into said ceramic substrate, whereby said ceramic substrate functions as a wafer prober.    
   
   
       3 . The ceramic substrate according to  claim 1 , further comprising: 
 a heat generation body as a conductor layer inside said ceramic substrate; and    a through-hole connected electrically to said heat generation body, wherein a projection is formed on a side wall of said through-hole so as to protrude into said ceramic substrate, whereby said ceramic substrate functions as a heater.    
   
   
       4 . The ceramic substrate according to  claim 1 , further comprising: 
 an electrostatic electrode as a conductor layer inside said ceramic substrate; and    a through-hole connected electrically to said electrostatic electrode, wherein a projection is formed on a side wall of said through-hole so as to protrude into said ceramic substrate, whereby said ceramic substrate functions as an electrostatic chuck.