| 摘要 |
PURPOSE:To form a bipolar transistor in a CMOS process having no Ic dependency, a large hFE and good high frequency characteristic by adding a P<+> type diffused layer for newly forming a base without forming a P<-> type well. CONSTITUTION:N-channel and P-channel MOS transistors are formed on an N type silicon substrate 20. In other words, after a window is opened at an oxide film such as an SiO2 oxide film 21, boron ions are implanted to form a base diffused layer 22. The diffusing depth and the density of the base layer at this time are set to levels used for a normal bipolar LSI. Then, an oxide film such as an SiO2 oxide film 23 is formed, a window for diffusing an emitter is opened, phosphorus or arsenic ions are then implanted to form an emitter region 24. A base leading high density P<+> type region 25 and an emitter leading electrode 26 are similarly formed in the CMOS process. An emitter electrode 26 is formed, for example, of polysilicon. |
