Semoconductor device and manufacture thereof

Abstract

Abstract PURPOSE:To manufacture an isolating structure between elements by the formation of porous substrate by dry etching without side etching, an anodic oxidation and the oxidation thereof by forming a pattern of ultrafine width at the periphery of an element region. CONSTITUTION:The first and second materials 4, 5 are accumulated on a silicon substrate 1 having the first oxidation resistant material 3 on the surface, and the material 5, to which the pattern of the material 4 is bonded at the edge, is removed by ethcing, thereby forming a groove (a). The substrate material exposed on the bottom of the groove (a) is etched to form a groove (b) on the substrate 1. Then, the material 5 is removed, with the material 4 as a mask the material 3 is removed. Then, the second oxidation resistant material 8 is accumulated, directional etching is performed, thereby allowing the side wall of the material 3 and the material 8 in the groove (b) to remain, and the material 8 except them is etched to expose the substrate 1. Then, the substrate 1, on which the material 3 is not covered, is formed in a porous state by anodic oxidation, and the porous region is formed by thermal oxidation to a thermally oxidized film 10.

Inventors

• 👤 Kohei Ebara
• 👤 江原　孝平
• 👤 Susumu Muramoto
• 👤 村本　進
• 👤 Seitaro Matsuo
• 👤 松尾　誠太郎

Bibliographic Details