| 摘要 |
PURPOSE:To perform a diffusion and particularly a selective diffusion of Al, Ga ions in an Si substrate accurately and inexpensively by injecting Al or Ga ions in the Si substrate from the surface of the substrate, coating an Si layer on the surface thereof, heat treating the same, and diffusing the Al, Ga ions in the prescribed depth in the substrate. CONSTITUTION:Al, or Ga ions are injected from one main surface of an Si substrate, and an Si layer is coated on the surface. The Si this coated is amorphous Si, and the thickness is higher than 1mum. The substrate is heated to activate the injected ions, and the ions are diffused in the prescribed depth, e.g., 0.02-0.05mum in the substrate. Accordingly, the Si layer coated newly prevents the external diffusion of the injected ions and also prevents the segregation of the injected ions in the surface of the substrate, thereby facilitating the selective diffusion. |
