| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a semiconductor device to solve a problem that leakage failure between a source and a drain frequently occurs in an LDMOSFET using a back surface of a silicon substrate as a source electrode when high concentration boron doped substrate is used as to reduce substrate resistance for improvement of an output efficiency, and it becomes clear based on the result of failure analysis that undesired stress due to a p-type polysilicon plug disposed from an impurity doped region of a source through a p-type epitaxy layer to a p-type substrate is a factor of the leakage failure. <P>SOLUTION: The semiconductor device including an LDMOSFET comprises a conductive plug extending downward from an upper surface in vicinity of an impurity doped region of a source of the LDMOSFET to vicinity of a silicon substrate through an epitaxy layer with a bottom edge staying in the epitaxy layer, and containing silicon as main composition. <P>COPYRIGHT: (C)2012,JPO&INPIT |
