Patent ID: 6849522

Claim:
A method of press-working an inorganic substrate, comprising disposing a combination set of laminating materials including an inorganic substrate made of a semiconductor wafer substrate or an inorganic continuously porous sintered substrate and auxiliary materials for a laminate working between upper and lower heat plates of a vacuum press machine which comprises as essential components staybars, upper and lower frames, upper and lower heat plates, means for heating the upper and lower heat plates, pressure loading means to the upper and lower heat plates and a sealed pot having the sealing function of reducing a pressure in an atmosphere between the upper and lower heat plates, and heating and pressurizing the combination set, wherein the vacuum press machine comprises as a pressurization system an air cylinder which drives a plunger by means of air pressure and, the upper and lower heat plates which have been heated up to a predetermined temperature are brought into contact with the combination set disposed between the heat plates after or before the initiation of pressure reduction of a press atmosphere or at a reduced pressure and then a low-pressure loading from the initiation of the pressurization to 0.05 MPa takes at least 10 seconds at the reduced pressure.