| 摘要 |
PURPOSE:To contrive the reduction in MOS capacitance with simple construction by a method wherein the surface of a protection film formed on the surface of an oxide film on a semiconductor substrate is provided with an extension electrode. CONSTITUTION:The oxide film 4 is formed after formation of a base 2 and an emitter 3 in a wafer 1, and electrodes 5 and 6 are connected to the base 2 and the emitter 3 via apertures 4A and 4B bored in the film 4 thereafter. Afterwards, the protection film 7 is formed so as to cover the film 4 and the electrodes 5 and 6. Apertures 8 and 9 are provided at parts of the film 7 corresponding to the electrodes 5 and 6, respectively; extension electrode sections 5A and 6A connected to each of the electrodes 5 and 6 via these apertures are formed on the surface of the film 7. Such a manner makes the MOS capacitance equivalent to a series capacitance of the capacitance of the film 4 and that of the film 7. Since the capacitance becomes smaller than the capacitance of the film 4, the MOS capacitance reduces. |
