摘要 |
A semiconductor device in the present invention is provided with a cathode layer of an N-type impurity region and an anode layer of a P-type impurity region formed on the cathode layer. A plurality of floating ring layers of the P-type impurity regions which is electrically floating is provided spaced apart from the anode layer on the main surface of the cathode layer. Then, well layers of the N-type impurity regions containing floating ring layers are provided. For example, each well layer can individually be provided to the floating ring layer. In this case, each floating ring layer may be spaced apart or overlapped one another. Accordingly, a semiconductor device serves to downsize a chip without changing a property of on-resistance or a breakdown voltage.
|