Carbon-containing aluminum nitride sintered body, and ceramic substrate for a semiconductor producing/examining device

Abstract

An aluminum nitride ceramic including a sintered body having an aluminum nitride matrix, a carbon contained in the aluminum nitride matrix, and a sintering aid. The carbon is undetectable on an X-ray diffraction chart or below a detection limit of the X-ray diffraction chart.

1 . An aluminum nitride ceramic comprising: 
 a sintered body having an aluminum nitride matrix, a carbon contained in the aluminum nitride matrix, and a sintering aid, wherein the carbon is undetectable on an X-ray diffraction chart or below a detection limit of the X-ray diffraction chart.    
     
     
         2 . The aluminum nitride ceramic according to  claim 1 , wherein the carbon is at least one of amorphous carbon and carbon forming solid solution in an aluminum nitride crystal phase.  
     
     
         3 . The aluminum nitride ceramic according to  claim 1 , wherein the carbon is in an amount of 200 to 5000 ppm in the aluminum nitride matrix.  
     
     
         4 . The aluminum nitride ceramic according to  claim 1 , wherein the sintering aid is at least one of an alkali metal oxide, an alkali earth metal oxide and a rare earth oxide.  
     
     
         5 . The aluminum nitride ceramic according to  claim 1 , wherein the sintering aid is in an amount of 0.1 to 10 wt %.  
     
     
         6 . The aluminum nitride ceramic according to  claim 1 , wherein the sintered body has a brightness of N4 or less defined in JIS Z 8721.  
     
     
         7 . The aluminum nitride ceramic according to  claim 1 , wherein the sintering aid is at least one of CaO, Y 2 O 3 , Na 2 O, Li 2 O and Rb 2 O.  
     
     
         8 . The aluminum nitride ceramic according to  claim 1 , wherein the sintered body is usable at a temperature of 100° C. to 1000° C.  
     
     
         9 . The aluminum nitride ceramic according to  claim 1 , wherein the sintered body has a volume resistivity of 10 8 Ω·cm at temperature of 500° C.  
     
     
         10 . The aluminum nitride ceramic according to  claim 1 , wherein the sintered body has a disc shape.