Polysilicon/metal contact resistance in deep trench
First Claim
1. A trench structure comprising:
- a trench in a semiconductor on insulator (SOI) substrate, wherein said trench extends from a surface of a semiconductor on insulator (SOI) layer of said SOI substrate through a buried dielectric layer of said SOI substrate into a base semiconductor layer of said SOI substrate;
an undoped semiconductor material fill present in a lower portion of said trench that is located in said base semiconductor layer;
a dielectric layer present on sidewalls of said trench and extending from a portion of said buried dielectric layer into said base substrate layer;
a metal containing layer present on said dielectric layer, wherein a contact portion of said metal containing layer extends above an upper surface of said undoped semiconductor material fill; and
a doped semiconductor material fill present in said trench extending from an upper portion of said trench that extends through said SOI layer of said SOI substrate into contact with said contact portion of said metal containing layer.
7 Assignments
0 Petitions
Accused Products
Abstract
A method of forming a trench structure that includes forming a metal containing layer on at least the sidewalls of a trench, and forming an undoped semiconductor fill material within the trench. The undoped semiconductor fill material and the metal containing layer are recessed to a first depth within the trench with a first etch. The undoped semiconductor fill material is then recessed to a second depth within the trench that is greater than a first depth with a second etch. The second etch exposes at least a sidewall portion of the metal containing layer. The trench is filled with a doped semiconductor containing material fill, wherein the doped semiconductor material fill is in direct contact with the at least the sidewall portion of the metal containing layer.
41 Citations
16 Claims
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1. A trench structure comprising:
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a trench in a semiconductor on insulator (SOI) substrate, wherein said trench extends from a surface of a semiconductor on insulator (SOI) layer of said SOI substrate through a buried dielectric layer of said SOI substrate into a base semiconductor layer of said SOI substrate; an undoped semiconductor material fill present in a lower portion of said trench that is located in said base semiconductor layer; a dielectric layer present on sidewalls of said trench and extending from a portion of said buried dielectric layer into said base substrate layer; a metal containing layer present on said dielectric layer, wherein a contact portion of said metal containing layer extends above an upper surface of said undoped semiconductor material fill; and a doped semiconductor material fill present in said trench extending from an upper portion of said trench that extends through said SOI layer of said SOI substrate into contact with said contact portion of said metal containing layer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
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Specification