CERAMIC SUBSTRATE, FIXING HEATER AND APPARATUS FOR FIXING

摘要

PROBLEM TO BE SOLVED: To shorten the working time by a laser scribing method. SOLUTION: Respective recessed parts 53 forming lines 52 for separation are overlapped for the lines 52 for separation formed by laser scribing on the lines 52 for separation to separate a substrate body in the substrate body of ceramics. Thereby, even when the depth of the respective recessed parts 53 is shallow, the substrate body can readily be separated with the lines 52 for separation. Even when the substrate body is formed of a material having a high thermal conductivity, e.g. aluminum nitride, the lines 52 for separation can be formed in a short time and the working time by laser scribing can be shortened.