| 摘要 |
PURPOSE:To simplify the manufacturing process by a method wherein a transistor having emitter layers of different junction depths in the same chip is formed only at a time of photoetching process. CONSTITUTION:An N-collector layer 2, an SiO2 thick film 5, thin films 6a, 6a' and 6b, Si3N4 films 7 and 17, and a P-base layer 3 are formed on a P type Si substrate 1, the films 6a', 6c', 7 and 17 being selectively removed by photoetching, and an SiO2 thick film 5a being then formed by the LOCOS method. Next, in order to form elements of different emitter junction depths in the same chip, only the SiO2 film 6a' and the Si3N4 film 7 are selectively photoetched, an N- emitter layer 19 and an N<+> collector layer 10 is formed by diffusion through the films 6a and 6b, and the Surface is changed into an impurity glass layer 11. After the glass layer 11 and the Si3N4 film 17 are removed over the entire surface, an N-emitter layer 12 and an N<+> collector layer 13 are formed by diffusion through thin films 6c and 6d. This construction enables to obtain the device of high reliablility by simplification of the manufacturing process. |
