Trench isolation structure and method of formation
View Patent ↗In general, the present invention discloses at least one trench isolation region formed in a semiconductor substrate to electrically and/or optically isolate at least one active region from another active region. The at least one trench isolation region comprises a bottom portion and first and second trench sidewalls. At least one trench sidewall is adjacent a doped region. The at least one sidewall adjacent a doped region has a higher impurity dopant concentration than impurity doped regions surrounding the at least one trench isolation region.
1. A semiconductor device, comprising:
a substrate having a first doped region of a first doping concentration of a first conductivity type, wherein said first doped region is a well formed within said substrate;
a second doped region within said first doped region having a second doping concentration higher than said first doping concentration of said first conductivity type;
a trench isolation region that isolates active components in the substrate, wherein the trench isolation region is formed at least in a portion of said first doped region of said substrate, wherein the trench isolation region has two sidewalls and a bottom portion between the two sidewalls, and wherein at least one of the two sidewalls of said trench isolation region is adjacent said second doped region; and
a third doped region within said first doped region having a third doping concentration, wherein a first part of the bottom portion of the trench isolation region is adjacent to the third doped region and wherein a second part of the bottom portion is adjacent to the first doped region.
2. The semiconductor device of claim 1 , wherein said first doped region is a blanket doped region of said substrate.
3. The semiconductor device of claim 1 , wherein a first portion of the third doped region adjacent said bottom portion of said trench isolation region is formed self-aligned to the second doped region adjacent at least one sidewall of said trench isolation region.
4. The semiconductor device of claim 1 , wherein a first portion of the third doped region adjacent said bottom portion of said trench isolation region overlaps the second doped region adjacent at least one sidewall of said trench isolation region.
5. A processing system, comprising:
a processor; and
at least one integrated circuit coupled to said processor, wherein said at least one integrated circuit and processor further comprising a semiconductor device with at least one trench isolation region, said semiconductor device comprising:
a substrate having a first doped region of a first doping concentration of a first conductivity type, wherein said first doped region is a well formed within said substrate;
a second doped region within said first doped region having a second doping concentration higher than said first doping concentration of said first conductivity type;
a trench isolation region that isolates active components in the substrate, wherein the trench isolation region is formed at least in a portion of said first doped region of said substrate, wherein the trench isolation region has two sidewalls and a bottom portion between the two sidewalls, and wherein at least one of the two sidewalls of said trench isolation region is adjacent said second doped region; and
a third doped region within said first doped region having a third doping concentration, wherein a first part of the bottom portion of the trench isolation region is adjacent to the third doped region and wherein a second part of the bottom portion is adjacent to the first doped region.
6. The processing system of claim 5 , wherein said first doped region is a blanket doped region of said substrate.
7. The processing system of claim 5 , wherein a first portion of the third doped region adjacent said bottom portion of said trench isolation region is formed self aligned to the second doped region adjacent at least one sidewall of said trench isolation region.
8. The processing system of claim 5 , wherein a first portion of the third doped region adjacent said bottom portion of said trench isolation region overlaps the second doped region adjacent at least one sidewall of said trench isolation region.