| 摘要 |
PROBLEM TO BE SOLVED: To inhibit diffusion of an acceptor element to another semiconductor layer located in a lower layer than a p-type semiconductor layer in a semiconductor device where an n-type semiconductor layer is formed on a p-type semiconductor layer by ion injection.SOLUTION: A semiconductor device comprises: a first semiconductor layer containing a first donor element at a first concentration; a second semiconductor layer which is formed on the first semiconductor layer and contains an acceptor element at a second concentration higher than the first concentration and has p-type conductivity; and a third semiconductor layer which is formed on the second semiconductor layer and contains a second donor element having an atomic weight smaller than that of the acceptor element and has n-type conductivity. The first semiconductor layer contains an acceptor element of the same kind in the second semiconductor layer at a concentration which decreases as depart from the second semiconductor layer, and a region where the concentration of the acceptor element in the first semiconductor layer becomes equivalent with the first concentration exists in a range of not less than 0.4 μm and not more than 0.8 μm from the second semiconductor layer.SELECTED DRAWING: Figure 1 |
