Ceramic-metal bonded body

Abstract

To form an electrostatic chuck, a bonding sheet is applied onto the upper surface of a cooling plate and then the cooling plate is placed in a vacuum dryer at a pressure of 2,000 Pa or less for a pre-bake treatment at 120° C. to 130° C. for 15 to 40 hours, followed by natural cooling. A plate is then stacked on the bonding sheet so that the lower surface of the plate is aligned with the upper surface of the bonding sheet, which is applied onto the cooling plate. The resulting stacked body is placed in a heat-resistant resin bag, and is then placed in an autoclave and treated together for several hours under pressure and heat.

What is claimed: 
     
         1 . A ceramic-metal bonded body comprising a ceramic plate, a metal supporting base, and a resin bonding sheet that bonds the plate to the supporting base,
 wherein when the bonded body is heated in a vacuum environment of 100 Pa at 120° C. for 300 hours, the amount of change in the weight of the bonding sheet is 50 μg/cm 2 , where the unit is microgram per square centimeter of a bonded surface, or less.   
     
     
         2 . A ceramic-metal bonded body comprising a ceramic plate, a metal supporting base, and a resin bonding sheet that bonds the plate to the supporting base,
 wherein when the bonded body is heated in a vacuum environment of 100 Pa at 120° C. for 300 hours, no bubbles are generated at a bonded interface between the plate and the bonding sheet and a bonded interface between the supporting base and the bonding sheet.   
     
     
         3 . The ceramic-metal bonded body according to  claim 1 , wherein the ceramic-metal bonded body is an electrostatic chuck used for fixing a wafer by applying suction in a semiconductor manufacturing process or a showerhead used for supplying and dispersing a reactant gas to a chamber in a semiconductor manufacturing process. 
     
     
         4 . The ceramic-metal bonded body according to  claim 2 , wherein the ceramic-metal bonded body is an electrostatic chuck used for fixing a wafer by applying suction in a semiconductor manufacturing process or a showerhead used for supplying and dispersing a reactant gas to a chamber in a semiconductor manufacturing process.