| 摘要 |
<p>PURPOSE:To obtain a mesa type pellet without cracks during the processes, by layering polycrystalline Si on an Si substrate, providing mesa grooves having a specified depth, covering the surface by a protecting film, providing a desired electrode on the surface, and providing isolation. CONSTITUTION:An N layer is formed on the entire Si surface having a P-N-P three layer structure, and said layer is covered with an SiO2 film 12. Polycrystalline Si 16 is grown on a P layer on the other surfce in gaseous phase. Heat treatment is performed at 800-900 deg.C. The surface concentration of the polycrystalline Si is about 10<19>/cm<2>, and the intimate adherence with electrode metal is enhanced. Then the polycrystalline Si is covered by a film 17 having etching resistant property. Holes are perforated in the SiO2 film 12 on the other surface, and the mesa grooves 13 are formed and covered by glass. Then electrode metal 14 is attached as usual, and the isolation is performed to obtain SCRs. In this constitution, the thickness of the thinnest part caused by the groove formation is about 0.1mm. or more, and the damage due to cracks in the substrate 11 can be reduced.</p> |
