| 摘要 |
PURPOSE:To prevent the occurrence of rosette by a method wherein a glass film containing impurities is provided on a diffusing semiconductor region in forming an impurity diffusion region and diffusion treatment is done by providing a protective film on only the surface of a semicondcutor substrate covered with no glass film. CONSTITUTION:An antimonial glass film is applied to the surface of a P type Si substrate 1 and a silicic acid glass film 6 including antimony of about 2,000Angstrom is formed by annealing treatment. Next, a nitride film 7 of about 1,000Angstrom in thickness is coated and covered on the surface of the film 6 and etching is removed by leaving the part on the region diffusing impurities. Then, plasma etching is applied to the film 6 by using the remained film 7 as a mask. Furthermore, after forming an oxide film 8 on the exposed surface of the substrate 1 by thermal oxidization, the film 7 is removed to perform thermal treatment under oxygen atmosphere and an antimonial diffusion layer 9 is obtained. The glass film 6 containing impurities is coated and covered on only the surface becoming a diffusion region. Therefore, no rosette is generated at unnecessary places. |
