| 摘要 |
<p>PURPOSE:To make a MOSFET cell fine, to increase a mounting density, to make an ON resistance low and to increase a breakdown-strength by a method wherein a size of a source region is prescribed in a self-aligned manner by an insulating film at a sidewall part of a gate electrode and a U-groove contact which is shallower than a depth of the source region is formed. CONSTITUTION:A source region of a power MOSFET is composed of a shallow low-concentration region 11 and a deep high-concentration region 12. A length in a transverse direction of the source region is self-aligned by a U-groove part to be used as a source electrode 9 and its size is uniform. Consequently, a size of a base region connected to the source electrode 9 is secured to be definite. As a result, a base resistance can be suppressed to be small, and a parasitic bipolar transistor operation is not caused.</p> |
