MIS transistor with three-layer, transistor insulating film

摘要

The transistor insulating region surrounds the transistor forming one. The insulating film (2) consists of three layers (3-5) of different materials, with first one (3) surrounding the transistor forming region, while the second layer is so formed on the first one as to surround also the transistor forming region. The third layer (5) is so formed on the second one as to form an aperture for the transistor forming region. The MIS transistor comprises a source (10) and a drain region (11) in the semiconductor substrate (1), spaced by a sandwiched channel region (12) in a formation for PN-junction ends in contact with the first layer of the insulating film.