Semiconductor structure having source/drain gouging immunity
There is set forth herein a method of fabricating a semiconductor structure, the method including forming a conductive metal layer over a source/drain region. The conductive metal layer in one aspect can prevent gouging of a source/drain region during removal of materials above a source/drain region. The conductive metal layer in one aspect can be used to pattern an air spacer for reduced parasitic capacitance. The conductive metal layer in one aspect can reduce a contact resistance between a source/drain region and a contact above a source/drain region.
1. A method comprising:
forming a conductive metal layer over a source/drain region;
forming a dielectric layer over the conductive metal layer;
removing material of the conductive metal layer to define a contact hole, wherein the removing includes removing material of the dielectric layer to expose the conductive metal layer within the contact hole;
filling the contact hole with a contact metal formation;
wherein the forming includes forming the conductive metal layer so that the conductive metal layer extends over a first gate adjacent a first end of the source/drain region and over a second gate adjacent a second end of the source/drain region, the conductive metal layer having a section extending from a first sidewall of the first gate to an opposing sidewall of the second gate.
2. The method of claim 1 , wherein the forming includes forming the conductive metal layer so that the conductive metal layer extends over a first gate adjacent a first end of the source/drain region and over a second gate adjacent a second end of the source/drain region.
3. The method of claim 1 , wherein the forming includes forming the conductive metal layer so that the conductive metal layer extends over a first gate adjacent a first end of the source/drain region and over a second gate adjacent a second end of the source/drain region, the conductive metal layer having a section extending from a first sidewall of the first gate to an opposing sidewall of the second gate, the conductive metal layer having a first vertically extending section extending adjacent to the first sidewall of the first gate, the conductive metal layer including a second vertically extending section adjacent to the opposing sidewall of the second gate.
4. The method of claim 1 , further comprising using the conductive metal layer to pattern air spacers.
5. The method claim 3 , wherein the first vertically extending section and the second vertically extending section are removed to define air spacers.
6. A semiconductor structure comprising:
a source/drain region having a first end adjacent a first gate and a second end adjacent a second gate;
a conductive metal layer formed on the source/drain region;
a dielectric layer formed adjacent a side of said first or second gate and over said conductive metal layer;
at least one air spacer adjacent said first gate or second gate patterned from the conductive metal layer; and
a contact metal formation formed above the conductive metal layer.
7. The semiconductor structure of claim 6 , wherein the conductive metal layer has a section that extends from a first sidewall of the first gate to an opposing sidewall of the second gate.
8. The semiconductor structure of claim 6 , wherein the conductive metal layer is formed of a first material and a second material different from the first material.
9. The semiconductor structure of claim 6 , wherein, the semiconductor structure has a first air space adjacent the first gate and a second air spacer adjacent the second gate.