| 摘要 |
PURPOSE:To obtain an IGFET having a high dielectric strength and a low ON resistance, by forming a groove which is not so deep as to reach the substrate, in an N type drain region neighbouring a P type channel forming region provided on a P type substrate. CONSTITUTION:A P type channel forming region 40 having an N<+> type source region 37, and an N tye drain region 32 having an N<+> layer 36 are formed on a P type Si substrate 30 having a P<+> layer 39 on the back surface thereof. A groove H, which is not so deep as to reach the substrate is formed in the N type region 32, and a drain electrode 44, a gate electrodd 43, a source electrode 45 and a back-gate electrode 46 are provided. Thereby, the depletion layer between the regions 32 and 30 reaches the groove H. Accordingly, a high dielectric strength and a low ON resistance are obtained as the groove is noneffective at ON. |
