STRENGTHENING ALUMINA SUBSTRATES BY INCORPORATING GRAIN GROWTH INHIBITOR IN SURFACE AND PROMOTER IN INTERIOR

摘要

A thin ceramic substrate having unusually high strength properties is manufactured by a casting process which produces a triple layered ceramic body. The exterior layers of the body having incorporated therein a grain growth inhibitor. The interior layer of the body has incorporated therein a grain growth promoter. Upon sintering, the composite body is defined by an interior grain size which is approximately twice as large as the exterior grain size.