Manufacture of semiconductor element

Abstract

Abstract PURPOSE:To increase the surface angle of a single crystal silicon island in an isolation surface section, and to prevent the deterioration of current-resistant capacitance due to the stepped disconnection of a metallic wiring or a change into a thin-film of the metallic wiring by forming a V trench to the single crystal silicon island through anisotropic etching in the isolation surface section through which the metallic wiring is passed. CONSTITUTION:A dielectric isolation substrate 11 is formed of a polycrystalline silicon support substrate 1, an N-single crystal silicon island 2 and an oxide film 3 for isolation, an oxide film 12 is shaped and an opening section 8 is formed. The isolation substrate 11 is anisotropic-etched by an alkali group etchant while using the oxide film 12 as a mask material, and a recessed section 9 is shaped to the support substrate 1. An oxide-film projecting section 3a and the oxide film 12 are removed extending over the whole surface. An oxide film 4 and an N<+> layer 6 as the diffusion layer for extracting potential of the single crystal silicon island 2 are shaped so as to contain an isolation surface section, and a metallic wiring 7 is formed. The acutest angle of the surface angle of the single crystal silicon island 2 in the isolation surface section is brought to 109 deg., thus improving the coverage of the metallic wiring 7 shaped in the isolation surface section even when a stepped section 5 is generated.

Inventors

• 👤 Yoshiyuki Kanai
• 👤 金井　美之

Bibliographic Details