Split contact structure and fabrication method thereof
View Patent ↗A split contact structure includes a semiconductor substrate having a major surface; a first upwardly protruding structure disposed on the major surface; a first cell contact region in the major surface and being close to the first upwardly protruding structure; a second upwardly protruding structure disposed on the major surface; a second cell contact region in the major surface and being close to the second upwardly protruding structure; a first patterned layer stacked on the first upwardly protruding structure; a second patterned layer stacked on the first upwardly protruding structure; a first contact structure disposed on a sidewall of the first upwardly protruding structure and being in direct contact with the first cell contact region; and a second contact structure disposed on a sidewall of the second upwardly protruding structure and being in direct contact with the second cell contact region.
1. A split contact structure, comprising:
a semiconductor substrate having a major surface;
a first upwardly protruding structure disposed on the major surface;
a first cell contact region in the major surface and being close to the first upwardly protruding structure;
a second upwardly protruding structure disposed on the major surface;
a second cell contact region in the major surface and being close to the second upwardly protruding structure;
a shallow trench isolation (STI) region between the first cell contact region and the second cell contact region; wherein the first cell contact region and the second cell contact region are both in contiguous with the STI region;
a first patterned layer stacked on the first upwardly protruding structure;
a second patterned layer stacked on the second upwardly protruding structure;
a first contact structure disposed on a sidewall of the first upwardly protruding structure and being in direct contact with the first cell contact region, wherein the first patterned layer protrudes from a top surface of the first contact structure; and
a second contact structure disposed on a sidewall of the second upwardly protruding structure and being in direct contact with the second cell contact region, wherein the second patterned layer protrudes from a top surface of the second contact structure.
2. The split contact structure according to claim 1 , wherein the first and second upwardly protruding structures extend along a first direction and the first and second patterned layers have a line-shaped pattern and extend along a second direction, wherein the first direction is perpendicular to the second direction.
3. The split contact structure according to claim 1 further comprising a dual-spacer structure on the first or second contact structure.
4. The split contact structure according to claim 1 , wherein the first and second contact structure comprises an inwardly curved sidewall profile.
5. The split contact structure according to claim 1 , wherein the first and second patterned layers are silicon oxide layers.
6. The split contact structure according to claim 1 , wherein the first and second upwardly protruding structures comprise a silicon lower portion, a metal portion directly on the silicon lower portion, and a silicon nitride layer stacked on the metal portion and covering the sidewalls of the metal portion.