| 摘要 |
PURPOSE:To prevent the breakdown due to the concentration of electric field by a method wherein the substrate plane for base formation is processed into a spherical plane. CONSTITUTION:An oxide film 8 is formed on the Si substrate 7, and its part is processed into a recess-form spherical shape. Next, a P<+> layer 11 is formed by the deposit and the thermal diffusion of a P type impurity 10 with the film 8 as a mask. Then, a window 13 for emitter formation is bored in an oxide film 12 formed at the time of the thermal diffusion of the P type impurity, where an N type impurity 14 is deposited. An impurity is thermally diffused thereto, thus forming an N<+> layer 15 serving as an emitter layer E on the layer 11. A contact window is bored on each layer, and then the terminals of the base B, collector C, and emitter E are led out. |
