A single crystal of β‐normalSiC was grown by chemical vapor deposition using an SiH4‐C3H8‐H2 system on a silicon substrate with a sputtered layer. The grown layer of 4 μm thickness was confirmed as a single crystal by examination with reflection electron diffraction and x‐ray diffraction. To reduce the large mismatch between β‐normalSiC and a silicon substrate, a sputtered β‐normalSiC layer was employed as a buffer layer. Even though the sputtered layer was polycrystalline, the subsequent layer deposited by CVD was a single crystal. The crystallinity of the deposited layer was strongly affected by the thickness of the sputtered layer, the substrate temperature during sputtering, and the temperature of chemical vapor deposition.

A planar mtallization process has been proposed, where contact windows or via holes of a high aspect ratio are refilled with tungsten by selective CVD employing wF6. In tungsten selective CVD, an appropriate choice of substrate material and surface cleaning prior to tungsten deposition is a key factor to success. For selective deposition onto A l , Al surface is coated with p.loSi2 thin layer, and contact resistivities of refilling tungsten with n+ Si and WSi2 coated Al are comparable to those of conventional Al metallization. Combining a interlevel insulator surface planarization process and a planar metallization process, a tri-level aluminum interconnection process of 1 micron feature size has been constructed, which has a scheme extensive to submicron feature size.

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