Metal/polysilicon gate trench power mosfet

摘要

The present disclosure relates to a power MOSFET device having a relatively low resistance hybrid gate electrode that enables good switching performance. In some embodiments, the power MOSFET device has a semiconductor body. An epitaxial layer is disposed on the semiconductor body. A hybrid gate electrode, which controls the flow of electrons between a source electrode and a drain electrode, is located within a trench extending into the epitaxial layer. The hybrid gate electrode has an inner region having a low resistance metal, an outer region having a polysilicon material, and a barrier region disposed between the inner region and the outer region. The low resistance of the inner region provides for a low resistance to the hybrid gate electrode that enables good switching performance for the power MOSFET device.

主权项

1. A transistor device, comprising:
a semiconductor substrate comprising an epitaxial layer disposed over a semiconductor body and a plurality of implantation regions disposed along a top surface of the epitaxial layer opposing the semiconductor body; a source electrode and a drain electrode located on opposite sides of the semiconductor substrate; and a hybrid gate electrode located within a trench extending into the semiconductor substrate and configured to control a vertical flow of current between the source electrode and the drain electrode, wherein the hybrid gate electrode comprises a plurality of nested regions that extend from a position at the top surface of the epitaxial layer to a position vertically under the plurality of implantation regions, and wherein one or more of the plurality of nested regions comprise a low resistance metal.