Method for fabricating semiconductor device having semiconductor circuit element in isolated semiconductor region
Abstract
Abstract A semiconductor integrated circuit device is fabricated in an epitaxial layer of an n-type Si on a substrate of p-type Si by forming semiconductor circuit elements within one surface of the epitaxial layer, forming a mask layer on the surface of the epitaxial layer, forming grooves through the mask layer, which surround each semiconductor circuit element, so as to expose the surface of the epitaxial layer, diffusing boron into the surface of the exposed portions of the epitaxial layer through the grooves, maintaining the substrate at a temperature of 700* C, and directing 1016 argon ions per square centimeter having an energy of 50 KeV toward the surface, whereby p-type regions are extended quickly from the surface of the epitaxial layer to that of the substrate to isolate the semiconductor circuit elements from each other.
Inventors
- 👤 T Tsuchimoto
Bibliographic Details
Claims Analysis
Total Claims: 6References Cited (Backward Citations)
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