Second Schottky contact metal layer to improve GaN Schottky diode performance
AssigneeVelox Semiconductor Corporation
InventorsTing Gang Zhu, Marek Pabisz
Life of this patent
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Abstract
A Schottky contact is disposed atop a surface of a semiconductor. A first Schottky contact metal layer is disposed atop a first portion of the semiconductor surface. A second Schottky contact metal is disposed atop a second portion of the surface layer and adjoins the first Schottky contact metal layer. The first Schottky contact metal layer has a lower work function than the second Schottky contact metal layer.
Claims33
A Schottky contact disposed atop a planar surface of a semiconductor, said Schottky contact comprising:
- a first Schottky contact metal layer that includes a plurality of stripes each having its bottom surface disposed on said planar semiconductor surface and spaced apart from each other;
- and
- a second Schottky contact metal layer having a bottom surface disposed on said planar semiconductor surface at least between adjacent ones of and at least adjoining outermost ones of said plurality of stripes of said first Schottky contact metal layer so that the bottom surfaces of said plurality of stripes are co-planar with the bottom surface of said second Schottky contact metal layer and the bottom surfaces of said plurality of stripes, said first Schottky contact metal layer having a lower work function than that of said second Schottky contact metal layer.
A method of forming a Schottky contact atop a planar surface of a semiconductor, said method comprising:
- forming a first Schottky contact metal layer that includes a plurality of stripes each having its bottom surface disposed on said planar semiconductor surface and spaced apart from each other;
- and
- forming a second Schottky contact metal layer having a bottom surface disposed on said planar surface at least between adjacent ones of and at least adjoining outermost ones of said plurality of stripes of said first Schottky contact metal layer so that the bottom surfaces of said plurality of stripes are co-planar with the bottom surface of said second Schottky contact metal layer, said first Schottky contact metal layer having a lower work function than said second Schottky contact metal layer.
A Schottky contact having improved metal-to-semiconductor adhesion, said Schottky contact comprising:
- a first Schottky contact metal layer that includes a plurality of stripes each having its bottom surface disposed on a portion of a planar surface of a semiconductor structure, said first Schottky contact metal layer including a higher work function metal and having improved adhesion to the semiconductor surface by being annealed at a temperature of at least 300° C. and at most 500° C.;
- and
- a second Schottky contact metal layer having a bottom surface disposed atop at least a portion of said first Schottky contact metal layer and on said planar semiconductor surface at least between adjacent ones of and at least adjoining outermost ones of said plurality of stripes of said first Schottky contact metal layer so that the bottom surfaces of said plurality of stripes are co-planar with the bottom surface of said second Schottky contact metal layer and the bottom surfaces of said plurality of stripes.
Dependencies are inferred from the claim text.