| 摘要 |
PURPOSE:To shorter reverse recovery time of a diode present between source and drain, by setting resistivity of an epitaxial layer to be M times (M>1) as large as resistivity determined by relation between resistivity and dielectric strength observed when extension of a depletion layer is ensured, and decreasing the thickness of the epitaxial layer corresponding thereto. CONSTITUTION:An N-type layer 2a is epitaxially grown on a highly doped N-type semiconductor substrate 1. A P-type diffused layer 3 is formed on a predetermined region on the layer 2a and, further, a highly doped N-type dif fused layer 4 is formed in a predetermined region on the layer 3. A gate elec trode G, a source electrode S and a drain electrode D are formed on predeter mined regions on the N-type expitaxial layer 2a, the P-type diffused layer 3 and the N-type diffused layer 4. Resistivity Pepi of the N-type epitaxial layer 2a is set to be twice (M=2) as large as resistivity Pepi determined by relation between dielectric strength and resistivity Pepi of the epitaxial layer as observed when extension of a depletion layer is ensured (preferably M>=1.5). In this man ner, a diode between the source and the drain is allowed to have shortened reverse recovery time without changing dielectric strength or ON resistance. |
