Patent ID: 6337252
Filing Date: 2002-01-08
Classification: H01L

Abstract:
A method of manufacturing a semiconductor device having a vertical PNP bipolar transistor formed on a P-type semiconductor substrate, characterized in that a step of forming an N-type bottom separation region on the P-type semiconductor substrate to separate the vertical PNP bipolar transistor, a step of forming a P-type collector region of the vertical PNP bipolar transistor, and a step of forming an N-type base region of the vertical PNP bipolar transistor are performed by using the same mask;wherein the mask has substantially a same thickness during the step of forming bottom separation region, the step of forming the P-type collector region and the step of forming the N-type base region, and the bottom separation region, the P-type collector region and the N-type base regions are created by varying energies used for doping.