| 摘要 |
PURPOSE:To accurately control the depth of impurity diffusion as well as to prevent the generation of crystal defects for the titled semiconductor device by a method wherein the silica film containing diffused impurities is applied in uniform thickness, and the diffusion depth at the circumferential part of the window for diffusion is restrained to the thickness same as that of the other part or below. CONSTITUTION:The silicon substrate 11, whereon the silica film 14 was applied, is placed in the furnace of approximately 200 deg.C, and the silica film 14 is sintered. Then, a silica film 15 containing diffused impurities is applied on the silica film 14. In this instance, the silica film 15 is applied almost in uniform thickness irrespective of existence or non-existence of a stepping. Subsequently, the silicon substrate 11 is placed in a diffusion furnace, the diffused impurities in the upper silicon film 15 are diffused on the silicon substrate 11 through the lower silica film 14, and a diffusion layer 16 is formed in the substrate 11. When the diffusion layer 16 is formed as above, the depth of diffusion at the circumferential part of the window 13 to be used for diffusion is formed same as that of the other part or, to be more precise, shallower than the other part. |
