PURPOSE: To prevent generation of crack, breakage, and exfoliation of a ceramic body due to thermal stress when a ceramic body is bonded to a mother material interposing an intermediate material by setting backward an edge of the intermediate material from the ceramic side to the mother material side gradually.

CONSTITUTION: A ceramic small piece 1 is bonded to a mother material 3 of a partner member interposing an intermediate material 2. In this case, an edge 2a of the intermediate material 2 is set backward gradually to the inner side than the edge 1a of the small ceramic piece 1 as the edge 2a of the intermediate material 2 is apart further from the small ceramic piece 1 side toward the mother material 3 side. By this constitution, a space for liberating thermal stress generated by the difference of coefft. of thermal expansion between the small ceramic piece 1 and the intermediate material 2 is formed in a part where the edge 2a of the intermediate material 2 is set back, thus, concentration of thermal stress to the periphery of interface between the small ceramic piece 1 and the intermediate material bonded thereto is moderated.