Patent ID: 7569177

Claim:
A method of producing ceramic multilayer substrates comprising: (1) providing a green composite laminate comprising a green multilayer mother substrate having first and second opposing main surfaces and comprising a plurality of ceramic green layers containing ceramic powder, and first and second shrink-suppressing layers on the first and second main surfaces of the mother substrate, respectively, wherein the first and second shrink-suppressing layers comprise a powder substantially incapable of being sintered under the sintering conditions for the ceramic powder of the green multilayer mother substrate; (2) forming a plurality of first grooves extending from the first shrink-suppressing layer side so as to pass through the first shrink-suppressing layer and reach a part of the green multilayer mother substrate; (3) providing an auxiliary sheet on the first shrink-suppressing layer after the first grooves are formed; (4) firing the green composite laminate under the sintering conditions for the ceramic powder; (5) removing the first and second shrink-suppressing layers to recover a sintered multilayer mother substrate, and (6) dividing the multilayer mother substrate along the first grooves to realize a plurality of ceramic multilayer substrates, wherein at least one of (a) the first shrink-suppressing layer and the second shrink-suppressing layer have different thicknesses, (b) the powders in the first and second shrink-suppressing layers have different average particles sizes and (c) the provided green composite laminate has wiring conductors disposed on the first and second main surfaces and the density of the wiring conductors on those main surfaces is different, is satisfied.