Lateral extended drain metal oxide semiconductor field effect transistor (LEDMOSFET) with tapered dielectric plates to achieve a high drain-to-body breakdown voltage, a method of forming the transistor and a program storage device for designing the transistor

摘要

A lateral, extended drain, metal oxide semiconductor, field effect transistor (LEDMOSFET) with a high drain-to-body breakdown voltage (Vb) incorporates gate structure extensions on opposing sides of a drain drift region. The extensions are tapered such that a distance between each extension and the drift region increases linearly from one end adjacent to the channel region to another end adjacent to the drain region. In one embodiment, these extensions can extend vertically through the isolation region that surrounds the LEDMOSFET. In another embodiment, the extensions can sit atop the isolation region. In either case, the extensions create a strong essentially uniform horizontal electric field profile within the drain drift. Also disclosed are a method for forming the LEDMOSFET with a specific Vb by defining the dimensions of the extensions and a program storage device for designing the LEDMOSFET to have a specific Vb.