Wide bandgap power device with self-aligned ohmic silicided regions
AssigneeWolfspeed, Inc.
InventorsThomas Harrington, Shadi Sabri
Life of this patent
Estimating the term…
Abstract
A power semiconductor device includes a semiconductor layer structure having a drift region of a first conductivity type, and a gate structure including a gate contact on the semiconductor layer structure and a silicide blocking layer on the gate contact opposite the semiconductor layer structure. A protective spacer is provided on a sidewall of the gate structure, where the protective spacer is directly on the semiconductor layer structure. The protective spacer may define an interface with the semiconductor layer structure that is free of a gate insulating layer therebetween. Related devices and fabrication methods are also discussed.
Claims27
A power semiconductor device, comprising:
- a semiconductor layer structure comprising a drift region of a first conductivity type;
- a gate structure comprising a gate contact on the semiconductor layer structure and a silicide blocking layer on the gate contact opposite the semiconductor layer structure;
- and
- a protective spacer on a sidewall of the gate structure, wherein the protective spacer is directly on the semiconductor layer structure.
A power semiconductor device, comprising:
- a semiconductor layer structure comprising a drift region of a first conductivity type and a source region of the first conductivity type;
- a gate structure on the semiconductor layer structure adjacent the source region, the gate structure comprising a gate contact and a silicide blocking layer on the gate contact opposite the semiconductor layer structure;
- an interlayer dielectric layer on the gate structure and comprising an opening therein that exposes the source region;
- and
- a first conductive silicide on the source region and extending beyond edges of the opening in the interlayer dielectric layer and between the interlayer dielectric layer and the semiconductor layer structure.
A power semiconductor device, comprising:
- a semiconductor layer structure comprising a drift region of a first conductivity type, and at least one source region of the first conductivity type;
- gate contacts on the semiconductor layer structure with the at least one source region therebetween;
- protective spacers on respective sidewalls of the gate contacts, wherein top portions of the gate contacts opposite the semiconductor layer structure are free of the protective spacers;
- an interlayer dielectric layer on the top portions of the gate contacts;
- and
- a first ohmic contact on the at least one source region and continuously extending between the protective spacers.
A method of fabricating a semiconductor device, the method comprising:
- providing a semiconductor layer structure comprising a drift region of a first conductivity type and at least one source region of the first conductivity type;
- providing gate contacts on the semiconductor layer structure;
- providing a first dielectric material on the gate contacts opposite the semiconductor layer structure as silicide blocking layers;
- providing a second dielectric material on respective sidewalls of the gate contacts as protective spacers;
- and
- providing a first conductive silicide on the at least one source region between the gate contacts.
-35. (canceled)
A method of fabricating a semiconductor device, the method comprising:
- providing a semiconductor layer structure comprising a drift region of a first conductivity type and at least one source region of the first conductivity type;
- providing a gate insulating material on the semiconductor layer structure;
- providing a gate contact material on the gate insulating material opposite the semiconductor layer structure;
- providing a first dielectric material on the gate contact material opposite the gate insulating material;
- and
- patterning the first dielectric material, the gate contact material, and the gate insulating material to form gate structures comprising gate contacts and silicide blocking layers thereon that are spaced apart on the semiconductor layer structure with the at least one source region therebetween.
-42. (canceled)
Dependencies are inferred from the claim text.