Method of making high voltage vertical field effect transistor with improved safe operating area

摘要

A vertical field effect transistor having a first low resistivity region which determines breakdown voltage and a second low resistively region which is formed underneath a portion of a source is provided. The second low resistivity region lowers the gain of a parasitic bipolar transistor, and lowers resistance of a base region under the source of the field effect transistor, improving the commutating safe operating area of the vertical field effect transistor.