Semiconductor device with back side metal structure
AssigneeInfineon Technologies AG
InventorGerhard Schmidt
Life of this patent
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Abstract
A semiconductor device includes a semiconductor body with a base layer and a field shaping zone of a first conductivity type. The base layer extends parallel to a back surface of the semiconductor body in a central portion and into an edge portion that surrounds the central portion. The field shaping zone is formed in the edge portion and has a maximum dopant concentration exceeding at least three times a maximum dopant concentration in the base layer. A back side metal structure directly adjoins the back surface in the central portion and extends over the edge portion. A dielectric structure is between the back side metal structure and the field shaping zone. Leakage current mechanisms reducing the reverse blocking capabilities are reduced.
Claims25
A semiconductor device, comprising:
- a semiconductor body that comprises a base layer and a field shaping zone of a first conductivity type, the base layer extending parallel to a back surface of the semiconductor body over a central portion and into an edge portion surrounding the central portion, the field shaping zone formed in the edge portion and having a maximum dopant concentration exceeding at least three times a maximum dopant concentration in the base layer;
- a back side metal structure directly adjoining the back surface in the central portion and extending into the edge portion;
- and
- a dielectric structure between the back side metal structure and the field shaping zone.
An insulated gate bipolar transistor, comprising:
- a semiconductor body that comprises a base layer and a field shaping zone of a first conductivity type, the base layer extending parallel to a back surface of the semiconductor body over a central portion and into an edge portion surrounding the central portion, the field shaping zone formed in the edge portion and having a maximum dopant concentration exceeding at least three times a maximum dopant concentration in the base layer;
- a back side metal structure directly adjoining the back surface in the central portion and extending into the edge portion;
- and
- a dielectric structure between the back side metal structure and the field shaping zone.
A method of manufacturing a semiconductor device, the method comprising:
- forming a base layer of a first conductivity type in a semiconductor body, the base layer extending parallel to a back surface of the semiconductor body over a central portion and into an edge portion surrounding the central portion;
- forming a field shaping zone of the first conductivity type in the edge portion, wherein a maximum dopant concentration in the field shaping zone exceeds at least three times a dopant concentration in the base layer;
- providing a dielectric structure directly adjoining the back surface in the edge portion;
- and
- providing a back side metal structure directly adjoining the back surface in the central portion and the dielectric structure in the edge portion.
A semiconductor device, comprising:
- a semiconductor body that comprises a base layer of a first conductivity type, the base layer extending parallel to a back surface of the semiconductor body over a central portion and into an edge portion surrounding the central portion;
- a back side metal structure directly adjoining the back surface in the central portion and extending into the edge portion;
- and
- a dielectric structure directly adjoining the back side metal structure, directly adjoining an outer surface of the semiconductor body perpendicular to the back surface, and extending into a well of a second conductivity type opposite to the first conductivity type, the well forming part of a front side edge termination construction.
Dependencies are inferred from the claim text.