| 摘要 |
<p>A method of making a semiconductor device such as a diode or MOSFET provided in a thin semiconductor film on a thin buried oxide is disclosed, in which 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. This structure is achieved by a method including the steps of forming an oxidation mask including silicon nitride on the thin semiconductor film, and then patterning a portion of the oxidation mask with a series of sequential openings of different widths, a portion of the openings having a width less than the maximum thickness of the top oxide insulation layer. The thin semiconductor film is then oxidized using the oxidation mask to grow the top oxide insulation layer and lateral drift region portions which change in thickness.</p> |
