| 摘要 |
PURPOSE:To make the starting points of each diffusion with a base and an emitter the same, to reduce the area of an element and to improve the degree of integration and increase the speed of processing by setling an emitter diffusion hole prior to the formation of a base diffusion layer. CONSTITUTION:An N<+> type buried layer 4 as a collector region in an N-P-N transistor is diffused into an element forming region on a P type silicon semiconductor substrate 5. An impurity is diffused, and a select oxide film 14 is formed to the surface. A select oxidation is executed, a silicon nitride film 13 is removed by hot phosphoric acid, and a P<+> type channel stopper region 15 is shaped while using the oxide film 14 on the N<+> type region 4 as a mask. The oxide films 12, 14 of the surface of the silicon semiconductor substrate 5 are removed, an N type epitaxial growth semiconductor layer 6 is formed on the upper surface of the substrate 5, and oxide films 7 for an isolation are formed through a select oxidation method. An emitter diffusion hole 11 is shaped to a thin oxide film 16 on the element forming region through photolithography technique while an N<+> layer 18 as a collector section and a P<+> layer as a base region 8 are formed. A polycrystalline silicon film 19 is deposited on the surface of an element, and arsenic ions are doped to the polycrystalline silicon film 19. |
