Integrated circuit, ldmos with trapezoid jfet, bottom gate and ballast drift and fabrication method

Abstract

Disclosed examples include LDMOS transistors and integrated circuits with a gate, a body region implanted in the substrate to provide a channel region under a portion of the gate, a source adjacent the channel region, a drain laterally spaced from a first side of the gate, a drift region including a first highly doped drift region portion, a low doped gap drift region above the first highly doped drift region portion, and a second highly doped region portion above the gap drift region, and an isolation structure extending through the second highly doped region portion into the gap drift region portion, with a first end proximate the drain region and a second end under the gate dielectric layer, where the body region includes a tapered side laterally spaced from the second end of the isolation structure to define a trapezoidal JFET region.