Semiconductor device having deep implantation region and method of fabricating same
AssigneeMacronix International Co., Ltd.
InventorsChing-Lin Chan, Cheng-Chi Lin, Shih-Chin Lien, Shyi-Yuan Wu
Life of this patent
Estimating the term…
Abstract
A semiconductor device includes a substrate having a first conductivity type, a high-voltage well having a second conductivity type and disposed in the substrate, a source well having the first conductivity type and disposed in the high-voltage well, a drift region disposed in the high-voltage well and spaced apart from the source well, and a deep implantation region having the first conductivity type and disposed in the high-voltage well between the source well and the drift region.
Claims17
A semiconductor device, comprising:
- a substrate having a first conductivity type;
- a high-voltage well having a second conductivity type and disposed in the substrate;
- a source well having the first conductivity type and disposed in the high-voltage well;
- a source region entirely disposed in the source well and having a doping concentration higher than a doping concentration of the source well;
- a drift region disposed in the high-voltage well and spaced apart from the source well;
- and
- a deep implantation region having the first conductivity type and disposed in the high-voltage well outside of the source well, and between the source well and the drift region,
- wherein the drift region includes a plurality of alternately arranged first sections and second sections in a top view of the semiconductor device,
- the drift region further including:
- a top region having the first conductivity type only in the first sections in a cross-sectional view of the semiconductor device;
- and
- a grade region having the second conductivity type in both of the first sections and the second sections in the cross-sectional view of the semiconductor device, the grade region being formed on top of the top region in each of the first sections.
A method for fabricating a semiconductor device, the method comprising:
- providing a substrate having a first conductivity type;
- forming a high-voltage well having a second conductivity type in the substrate;
- forming a source well having the first conductivity type in the high-voltage well;
- forming a source region entirely in the source well and having a doping concentration higher than a doping concentration of the source well;
- forming a drift region in the high-voltage well and spaced apart from the source well;
- and
- forming a deep implantation region having the first conductivity type in the high-voltage well outside of the source well, and between the source well and the drift region,
- wherein the drift region includes a plurality of alternately arranged first sections and second sections in a top view of the semiconductor device,
- the forming of the drift region in the high-voltage well further including:
- forming a top region having the first conductivity type only in the first sections in a cross-sectional view of the semiconductor device;
- and
- forming a grade region having the second conductivity type in both of the first sections and the second sections in the cross-sectional view of the semiconductor device, the grade region being formed on top of the top region in each of the first sections.
Dependencies are inferred from the claim text.