| 摘要 |
PURPOSE:To obtain a separated region not generating stress by, when insulation- separating an N-type single crystal Si layer by use of a dielectric, after firstly boring an annular V-shaped groove in the Si layer and forming a P-type region at the side wall and the bottom of the groove by diffusion, anodizing the Si layer to make a porous Si and heat-treating the porous Si to convert it into SiO2. CONSTITUTION:An N-type layer 11 is epitaxially grown on a P-type Si substrate 10, covered with a mask subjected to etching and an annular V-shaped groove 12 not reaching the substrate 10 is bored therein. Next, using the same mask or another mask a P-type region 13 is formed by diffusion in the side wall and the bottom of the groove 12, the P-type region in the bottom reaching the substrate 10. The P-type region 13 is anodized using hydrogen fluide solution to convert it into a porous Si region 14. Then, the region 14 is heat-treated in an oxidizing atomosphere to convert it into an SiO2 layer 15, thereby obtaining an island-shaped dielectric separating region 11 surrounded by a layer 15 in the layer 11. This does not generate the stress applied to the layer 11 owing to formation of the separated region, resulting in no crystal defect. |
