| 摘要 |
PURPOSE:To improve the current amplification factor of a lateral P-N-P transistor by forming an N diffusion region between a P type region as an emitter and an N<+> type buried layer just under the P type region. CONSTITUTION:Sb, etc. are deposited onto a high-resistance P<-> type Si substrate 1 while using an oxide film 9 as a mask, and the N<+> diffusion layer 2 for burying is formed. An impurity such as P is introduced to one part of the surface of the N<+> buried layer 2 through deposition or ion implantation of an oxide film 10. A low-concentration N<-> type epitaxial layer 3 is shaped to the whole surface. P is ''arising''-diffused into the epitaxial layer at that time, and an N region (CNH)8 is formed. A P isolation part 4 is diffused, and P<+> type regions 5, 6 as emitter-collector are diffused while using an oxide film 11 as a mask. The P<+> layer 5 is shaped sufficinelty deeply so as to be contacted with an N region 8 in the epitaxial layer. |
