Semiconductor device having metal gate and poly gate
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsAlexander Kalnitsky, Wei-Cheng Wu, Harry-Hak-Lay Chuang
Life of this patent
Estimating the term…
Abstract
A semiconductor device includes a substrate, a first well, a second well, a metal gate, a poly gate, a source region, and a drain region. The first well and the second well are within the substrate. The metal gate is partially over the first well. The poly gate is over the second well. The poly gate is separated from the metal gate, and a width ratio of the poly gate to the metal gate is in a range from about 0.1 to about 0.2. The source region and the drain region are respectively within the first well and the second well.
Claims20
A method of fabricating a semiconductor device, comprising:
- forming shallow trench isolation (STI) structures in a substrate;
- forming a dummy gate stack and a poly gate stack over the substrate, wherein the dummy gate stack has a lateral dimension wider than a lateral dimension of the poly gate stack;
- forming a source region between the dummy gate stack and a first one of the STI structures;
- forming a drain region between the poly gate stack and a second one of the STI structures;
- after forming the drain region between the poly gate stack and the second one of the STI structures, conformally depositing an oxide material layer over the substrate, the dummy gate stack and the poly gate stack;
- patterning the oxide material layer;
- and
- replacing the dummy gate stack with a metal gate stack, wherein the metal gate stack has a lateral dimension wider than the lateral dimension of the poly gate stack.
A method of fabricating a semiconductor device, comprising:
- forming a first well and a second well in a substrate, wherein the first well and the second well include different types of dopants, and the first well is a neighbor to the second well;
- forming a dummy gate stack and a poly gate stack on the substrate, wherein the dummy gate stack and the poly gate stack are physically separated from each other;
- forming a source region adjacent to the dummy gate stack, wherein the source region is in the first well;
- forming a drain region adjacent to the poly gate stack, wherein the drain region is in the second well;
- and
- replacing the dummy gate stack with a metal gate stack, wherein the metal gate stack overlaps the first well and the second well, and the poly gate stack overlaps the second well and does not overlap the first well.
A method of fabricating a semiconductor device, comprising:
- forming a first well and a second well in a substrate, wherein the first well and the second well include different types of dopants, and the first well is a neighbor to the second well;
- forming a dummy gate stack and a poly gate stack on the substrate, wherein the dummy gate stack is on the first well and the second well, and the poly gate stack is on the second well and is discontinuous from the dummy gate stack;
- forming a source region adjacent to the dummy gate stack, wherein the source region is in the first well;
- forming a drain region adjacent to the poly gate stack, wherein the drain region is in the second well;
- depositing a hard mask on the poly gate stack, wherein the hard mask is made of polymer or metal;
- and
- after depositing the hard mask on the poly gate stack, replacing the dummy gate stack with a metal gate stack.
Dependencies are inferred from the claim text.