| 摘要 |
PURPOSE:To shorten the diffusing time of a semiconductor device by forming impurity diffusion for forming an isolating region following the manner of the other region when forming a plurality of semiconductor devices on the same semiconductor substrate. CONSTITUTION:In forming a plurality of planar thyristors as isolated with an isolating region on an N type semiconductor substrate, an isolating layer 3 is formed not to penetrate the substrate 1 by the boron impurity diffusion thereon. In this step, unisolated layer 10 exists in the N type region. In forming boron impurity diffusion on P type impurity regions 4, 5, the layer 10 is erased, and an isolating layer 3 is completed through the substrate 1. Since this can shorten the diffusing time of boron drive to form the isolating layer, the N type base layer 7 on the silicon surface is retained widely, and various characteristics of the thyristor such as forward and reverse protective voltage characteristics can be improved. |
