| 摘要 |
PURPOSE:To isolate elements with each other via a complete filmlike silicon oxidized film by thermally oxidizing an oxygen-added thin silicon film formed in the groove formed on the surface of a silicon substrate, thereby eliminating an air gap presented in the oxygen-added thin silicon film and improper filmlike part. CONSTITUTION:An oxygen added thin silicon film 7 is thermally oxidized in dipped oxidative atmosphere to form a completely filmlike silicon oxidized film 72 having 2 of oxygen composition ratio to silicon. Air gap is compressed due to the volumetric expansion of the case that the film 72 is varied to obtain a completely filmlike property so that the volumetric expansion becomes small amount. Thus, no dislocation of crystal is produced in the silicon substrate 1. Then, the film 72 except the groove is removed by anisotropic etching, thereby forming a silicon oxidized film 73 only in the groove 4, and removing a silicon nitrided film 6 and a silicon oxidized film 5 on an element region 3. A silicon oxidized film 51, a silicon nitrided film 61 and a silicon oxidized film 73 are formed only in the inner surface of the groove 4, these insulators can isolate elements with each other, and the substrate 1 can be exposed on an element region 3. |
