Patent ID: 7309877

Claim:
A semiconductor device having: at least one pixel comprising: a switching transistor which comprises a source region connected to a signal line and a drain region, both of which are of a first conductivity type and formed in a base semiconductor region of a second conductivity type, and a gate electrode formed on a region between said source region and said drain region, with an insulating layer therebetween, and connected to a scan line; a signal accumulation capacitor formed in said base semiconductor region of said second conduction type, said signal accumulation capacitor includes two semiconductor regions of said second conductivity type formed in said base semiconductor region, and an electrode formed on a region between said two semiconductor regions, with an insulating layer therebetween; a reflection electrode which serves as a pixel electrode is formed in connection with said drain region of said switching transistor and said electrode of said signal accumulation capacitor; and a bias semiconductor region of said second conduction type is formed in said base semiconductor region, separately from said semiconductor regions constituting said signal accumulation capacitor.