Lateral thin-film SOI devices with graded top oxide and graded drift region

摘要

A lateral thin-film Silicon-On-Insulator (SOI) device includes a lateral semiconductor device such as a diode or MOSFET provided in a thin semiconductor film on a thin buried oxide. The lateral semiconductor device structure includes at least two semiconductor regions separated by a lateral drift region. A top oxide insulating layer is provided over the thin semiconductor film and a conductive field plate is provided on the top oxide insulating layer. In order to provide enhanced device performance, a portion of the top oxide layer increases in thickness in a substantially continuous manner, while a portion of the lateral drift region beneath the top oxide layer decreases in thickness in a substantially continuous manner, both over a distance which is at least about a factor of five greater than the maximum thickness of the thin semiconductor film.