| 摘要 |
PURPOSE:To increase the degree of integration and density while preventing the generation of a punch through among elements by isolating one conduction type semiconductor substrate and a reverse conduction type region by a wedge-shaped insulator, one surface thereof is approximately vertical. CONSTITUTION:A thermal oxide film 22, a silicon nitride film 23 and an Al film 24 are formed onto an N type silicon substrate 21 in succession, and a concave section 26 is formed through etching while using a resist mask 25 or both the resist mask 25 and the Al film 24 as masks. A first insulating film is deposited to the whole surface. When the whole surface is etched by an ammonium fluoride liquid, a V-shaped groove 28 is formed around the concave section 26. A wafer is treated by a mixed flow of sulfuric acid and hydrogen peroxide, and shape of which the concave section is buried with a SiO2 film 27 is obtained. The V-shaped groove 28 is buried completely with a silicon nitride film 29, and a resist film 30 is applied onto the film 29 to flatte the surface. The whole surface is etched until the insulating film 27 is exposed. The insulating film 27 is removed, and the substrate 21 of the bottom of the recessed section is exposed. A silicon single crystalline layer 32 of the same shape as the substrate and a reverse conduction type silicon single crystalline layer 33 are formed. |
