| 摘要 |
PURPOSE:To improve disruptive strength in case of latching of L load by forming a deep P<+> type well having high concentration by one part except the channel section of the P type well of a vertical MOSFET. CONSTITUTION:The deep P<+> type wells 7 having high concentration are formed by one parts except the channel sections of the P type wells 3 of the vertical MOSFET. Surface concentration shall be at least 1X10<17>atoms/cm<3> or more in the concentration of the P<+> type wells 7. Accordingly, the device does not function as a parasitic bipolar transistor by short-circuiting the base and emitter of a bipolar NPN transistor and lowering base resistance, and breakdown voltage BVDSS is increased, thus improving the dielectric resistance of the L load. |
