| 摘要 |
PURPOSE:To enable formation of a P type layer easily with boron in preferable controllability by forming an Si3N4 film on an Si substrate and implanting boron- containing molecular ions through the film thereto. CONSTITUTION:An SiO2 film 2 is formed on an N type Si substrate 1, and an opening is perforated thereat. Then, a thin Si3N4 film 3 is formed thereon. Thereafter, boron-containing ions 4 are implanted into the substrate 1. In this step, nitrogen in the film 3 is introduced into the substrate 1 by a knock-on effect caused by an impact of the ions 4 to the film 3. Resultantly, there is formed a layer 5 to which nitrogen, boron, fluorine and chlorine are introduced into the substrate 1. Subsequently, a P type layer 6 is formed thereon by a heat treatment. In this manner, there can be formed a P type layer having uniform and shallow depth of junction. |
