| 摘要 |
PROBLEM TO BE SOLVED: To obtain the clamp jig, which is suitable for a high density signal recording disk, by utilizing the ceramic sintered compact mainly made of the crystal structure, which is the compound of lithium aluminum silicate crystals and calcium silicate crystals, and having the specific thermal expansion coefficient similar to a silicon substrate. SOLUTION: The crystal structure is a ceramic sintered compact and is mainly made of the compound of lithium aluminum silicate crystals having the weight percentage of 10 to 90 and calcium silicate crystals having the weight percentage of 90 to 10 and has a thermal expansion coefficient of 1.0 to 5.0×10<-6> / deg.C similar to a silicon substrate. The material powder is adjusted and formed so that the containing amount of each element of the sintered compact in terms of the oxide converted weight % becomes 0.7<=Li2 O<=7.0, 47.0<=SiO2 <=60.0, 4.0<=CaO<=44.0 and 3.0<=Al2 O3 <=30.0 or after melting, it is casted, formed and heat treated at high temperature of 700 to 1300 deg.C. If the material, which includes amorphous powder, is to be used, it is desirable to be heated to 700 to 1000 deg.C, held and heat treated at 1100 to 1300 deg.C. |
