Semiconductor Device Including a LDMOS Transistor and Method
AssigneeInfineon Technologies AG
InventorsAlbert Birner, Helmut Brech, Matthias Zigldrum, Michaela Braun, Christian Eckl
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Abstract
In an embodiment, a semiconductor device includes a semiconductor substrate having a front surface, a LDMOS transistor in the front surface, and a metallization structure arranged on the front surface. The metallization structure includes at least one cavity arranged in at least one dielectric layer.
Claims27
A semiconductor device, comprising:
- a semiconductor substrate comprising a front surface,
- a LDMOS (Lateral Diffused Metal Oxide Semiconductor) transistor in the front surface;
- and
- a metallization structure arranged on the front surface,
- wherein the metallization structure comprises at least one cavity arranged in at least one dielectric layer.
The semiconductor device of clam 8, wherein the first dielectric layer comprises three sublayers, the first sublayer comprising BPSG, the second sublayer comprising SiN and the third sublayer comprising SiOx, and wherein the second dielectric layer comprises SiON, the third dielectric layer comprises SiN and the fourth dielectric layer comprises SiOx.
The semiconductor device of clam 5, wherein the first cavity is arranged between drain-sided edge of a field plate and a drain region of the LDMOS transistor.
An LDMOS transistor, comprising:
- a semiconductor substrate comprising a front surface,
- a doped source region, a gate, a doped drain region, a doped channel region, a doped drain drift region and a doped body contact region arranged in the front surface;
- a metallization structure arranged on the front surface, the metallization structure comprising one or more dielectric layers, one or more conductive redistribution layers arranged between the one or more dielectric layers and one or more conductive vias extending through the one or more dielectric layers;
- and
- at least one cavity defined by dielectric material, the at least one cavity comprising a dielectric constant which is lower than a dielectric constant of the dielectric material defining the at least one cavity.
A method, comprising:
- applying a dielectric layer to a front surface of a semiconductor substrate comprising a LDMOS transistor structure;
- forming an opening in at least one dielectric layer;
- and
- covering the opening with a further dielectric layer to seal the cavity.
A method, comprising:
- positioning one or more cavities having a dielectric constant that is less than a dielectric constant of dielectric material of a metallization structure arranged on a LDMOS transistor in positions so as to reduce one or more of the group consisting of an electric field in the metallization structure at those positions, capacitive coupling between drain and gate, capacitive coupling between source and gate, and capacitive coupling between source and drain.
Dependencies are inferred from the claim text.