Patent ID: 7928445
Filing Date: 2011-04-19
Classification: H01L

Abstract:
1. A semiconductor device comprising a MOS transistor which comprises: a semiconductor substrate of a first conductivity type; a drain region and a source region both of a second conductivity type disposed spaced apart from each other on a surface of the semiconductor substrate, a gate insulating film formed on the semiconductor substrate between the source region and the drain region; and a gate electrode formed on the gate insulating film; wherein the semiconductor substrate between the source region and the drain region provides a channel region, the drain region comprising a first drain region disposed spaced apart from the gate insulating film and the channel region, and a second drain region disposed between and adjacent to the first drain region and the channel region, wherein the gate electrode comprises a first gate electrode formed on the gate insulating film and a second gate electrode formed on the first gate electrode via a gate electrode insulating film, wherein a gate wiring for providing a gate voltage is connected to the second gate electrode but not to the first gate electrode, wherein, as seen from above, the edges of the second gate electrode are partly or entirely disposed outside the edges of the first gate electrode, wherein a portion of the second gate electrode that is disposed outside the edges of the first gate electrode is disposed over the field insulating film, the portion being disposed over the first gate electrode via the gate electrode insulating film.