| 摘要 |
PURPOSE:To enable to realize a bi-polar IC of a high withstand voltage composed by the combination of a lateral p-n-p transistor with a vertical n-p-n transistor even at the circuit part whereon a high voltage is applied by a method wherein the development of the depletion layer at the collector junction is restrained at the time of impressing a collector bias. CONSTITUTION:A ring aperture is formed by selectively removing an SiO2 film in ring form, and a ring collector region 3 is formed by ion-implanting boron to the surface of a semiconductor substrate within the aperture, or by solid- diffusion from an oxide doped with boron. A conductive film is selectively opened at the first position of the ring form along the inner peripheral side of the collector region 3 and the second position at the center of the first position. Next, after coating the first ring aperture 15 with a resist 17, the SiO2 film 5 exposed to the second aperture 16 at the center is removed by etching, thus exposing the surface of the semiconductor substrate in said aperture 16. After exfoliating the resist 17, boron is ion-implanted to the entire surface. Finally, a metallic film is adhered over the entire surface, and thereafter patterning is performed, resulting in the formation of electrode films 10 and 11 on the first conductive film part 6 and the second one 7. |
