SEMICONDUCTOR DEVICE AND FABRICATION METHOD

摘要

The present invention provides an SOI device which has high breakdown voltage, wide stable operation range, good thermal dissipation, and high effective conductance and good frequency characteristics, and a method for fabricating the device. In a semiconductor device, a BOX region is formed on a part of a surface layer of a p substrate. The BOX region is formed around a point where a vertical line is dropped from the center of the gate structure portion, and isolates a drain region and an extended drain region from the p^- substrate. The thickness of the drain region is in a 150 nm to 300 nm range, and the thickness of the BOX region is 150 nm or more.