Texas Instruments Incorporated
TRANSISTOR WITH FIELD PLATE OVER TAPERED TRENCH ISOLATION

Abstract:

An integrated circuit (IC) includes a field-plated transistor including a substrate having a semiconductor surface layer, at least one body region in the semiconductor surface layer, and at least a first trench isolation region adjacent to the body region having at least a first tapered sidewall that has an average angle along its full length of 15 to 70 degrees. A gate is over the body region. A field plate is over the first tapered trench isolation region. A source is on one side of the field plate and a drain is on an opposite side of the field plate. The IC also includes circuitry for realizing at least one circuit function having a plurality of transistors which are configured together with the field-plated transistor that utilize second trench isolation regions for isolation that have an average angle of 75 and 90 degrees.