Patent ID: 7332231

Claim:
A thin film electronic component, comprising: a ceramic substrate base portion having pores and comprising ceramic; a dense glass-ceramic mixed layer formed on the ceramic substrate base portion, said dense glass-ceramic mixed layer comprising glass dispersed in the ceramic of a surface portion of the ceramic substrate so as to fill the pores therein with glass; and a thin film conductor layer formed on a surface of the dense glass-ceramic mixed layer; said dense glass-ceramic mixed layer is prepared by subjecting a glass layer formed on a surface of the ceramic substrate base portion to heat and pressure treatment to form said dense glass-ceramic mixed layer at the surface of the ceramic substrate and a glass glaze layer on the dense glass-ceramic layer, and then polishing to expose a surface of the dense ceramic-glass mixed layer; wherein said surface of the dense glass-ceramic mixed layer has an arithmetic average surface roughness (Ra) of 0.02 μm or less and a maximum height (Ry) of 0.25 μm or less, wherein said dense glass-ceramic mixed layer does not have a pore while said ceramic substrate base portion has pores, wherein an amount of the glass-filled in pores of the dense glass-ceramic mixed layer is 0.5-50% by mass, and wherein the dense glass-ceramic mixed layer has a thickness of 10 μm or more and not greater than 100 μm.