MOS TRANSISTOR AND MANUFACTURE THEREOF

摘要

PROBLEM TO BE SOLVED: To elongate a channel on a drain side in width by a method, wherein a gate is formed like a ring on a semiconductor substrate where a groove is provided, a second conductive-type first impurity region is formed along the inner side of the gate, and a second conductive-type second impurity region is formed along the outer side of the gate. SOLUTION: A groove is provided to the surface of an epitaxial layer 12 on a semiconductor substrate 10, and a gate electrode 26 is formed on the epitaxial layer 12 where the groove is provided. A second conductive-type first impurity source region 32 of high concentration is formed along the inner side of the gate electrode 26. A second conductive-type second impurity drain region 32 of high concentration is formed along the outer side of the gate electrode 26, and a body region 28 is formed covering a high-concentration region 32. By this setup, a channel on a drain side can be enhanced in width, and a MOS transistor of this constitution can be lessened in operating resistance.