| 摘要 |
The present invention provides a method of manufacturing a semiconductor device, comprising the steps of selectively diffusing an impurity of a first conductivity type and another impurity of a second conductivity type into a main surface region of a semiconductor substrate (21) so as to form first semiconductor regions (22) of the first conductivity type and second semiconductor regions (23) of the second conductivity type, forming a first semiconductor layer (25) of the second conductivity type on the semiconductor substrate (21), said first semiconductor layer (25) being of at least a single layer structure, forming element regions (26, 27, 28, 29) of the first and second conductivity types by thermal diffusion of impurities into the first semiconductor layer (25), and polishing the opposite main surface of the semiconductor substrate (21) to expose the first semiconductor regions (22) of the first conductivity type and the second semiconductor regions (23) of the second conductivity type. The first semiconductor layer (25) may be of a laminate structure consisting of a plurality of semiconductor layers differing from each other in the impurity concentration. <IMAGE> |
