Recessed drift region for HVMOS breakdown improvement
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsWilliam Wei-Yuan Tien, Fu-Hsin Chen
Life of this patent
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Abstract
A high-voltage metal-oxide-semiconductor (HVMOS) device having increased breakdown voltage and methods for forming the same are provided. The HVMOS device includes a semiconductor substrate; a gate dielectric on a surface of the semiconductor substrate; a gate electrode on the gate dielectric; a source/drain region adjacent and horizontally spaced apart from the gate electrode; and a recess in the semiconductor substrate and filled with a dielectric material. The recess is between the gate electrode and the source/drain region, and is horizontally spaced apart from the gate electrode.
Claims20
A semiconductor structure comprising:
- a semiconductor substrate;
- a gate dielectric on a surface of the semiconductor substrate;
- a gate electrode on the gate dielectric;
- a source/drain region adjacent and horizontally spaced apart from the gate electrode;
- a recess in the semiconductor substrate and filled with a dielectric material, wherein the recess is between the gate electrode and the source/drain region, wherein the recess is horizontally spaced apart from the gate electrode, and wherein the recess and the source/drain region are not vertically overlapped, and are physically separated from each other;
- and
- a lightly doped source/drain region having a lower impurity concentration than the source/drain region, wherein the lightly doped region is of a same conductivity type as the source/drain region and has an edge substantially aligned with an edge of the gate electrode, and wherein the recess and the source/drain region are in the lightly doped source/drain region.
A semiconductor structure comprising:
- a substrate;
- a gate dielectric on a surface of the substrate;
- a gate electrode on the gate dielectric;
- a well region of a first conductivity type underlying the gate electrode and extending beyond edges of the gate electrode;
- a lightly doped region of a second conductivity type opposite the first conductivity type in the well region, wherein the lightly doped region has an edge adjacent an edge of the gate electrode;
- a heavily doped region of the second conductivity type in the lightly doped region;
- a recess extending from a top surface of the lightly doped region into the lightly doped region, wherein the recess is horizontally spaced apart from the gate electrode, and is horizontally between the gate electrode and the heavily doped region;
- a dielectric region in the recess;
- a contact etch stop layer extending over the gate electrode, the lightly doped region, and the heavily doped region, and extending into the recess, wherein a portion of the contact etch stop layer in the recess forms a first portion of the dielectric region, and wherein a bottom surface of the first portion contacts a semiconductor material of the substrate;
- and
- an inter-layer dielectric over the contact etch stop layer, wherein the inter-layer dielectric extends into the recess and forms a second portion of the dielectric region.
A semiconductor structure comprising:
- a substrate;
- a well region of a first conductivity type in the substrate;
- a gate dielectric on a surface of the well region;
- a gate electrode on the gate dielectric;
- a gate sidewall spacer on a sidewall of the gate electrode;
- a lightly doped region of a second conductivity type opposite the first conductivity in the well region, wherein the lightly doped region has an edge substantially aligned to an edge of the gate electrode;
- a heavily doped region of the second conductivity type in the lightly doped region;
- and
- a recess in the lightly doped region and between the gate electrode and the heavily doped region, wherein the recess has an inner edge substantially aligned with an outer edge of the gate sidewall spacer, wherein the recess is filled with a dielectric material, and wherein the heavily doped region is spaced apart from the recess.
Dependencies are inferred from the claim text.