Semiconductor structure and method for manufacturing the same
A method for manufacturing a semiconductor structure is provided. The method includes: receiving a substrate having a first epitaxy region in a first transistor of a first conductive type and a second epitaxy region in a second transistor of a second conductive type; introducing an agent onto the first epitaxy region and the second epitaxy region, wherein the agent is selectively deposited to the second epitaxy region; selectively depositing a first metal layer on the first epitaxy region; and depositing a second metal layer on the first epitaxy region and the second epitaxy region. A semiconductor structure according to the method is also provided.
1. A method for manufacturing a semiconductor structure, comprising:
receiving a substrate having a first epitaxy region in a first transistor and a second epitaxy region in a second transistor, wherein the first epitaxy region has a first germanium concentration greater than 50%;
introducing a hydroxyl-sensitive agent directly onto the first epitaxy region and the second epitaxy region, wherein the hydroxyl-sensitive agent is selectively bonded to the second epitaxy region;
selectively depositing a first metal layer on the first epitaxy region; and
depositing a second metal layer on the first epitaxy region and the second epitaxy region;
wherein the hydroxyl-sensitive agent is bonded to hydroxyl groups on a surface of the second epitaxy region; and
wherein the second epitaxy region comprises silicon phosphorus.
2. The method of claim 1 , wherein depositing the first metal layer comprises a plasma-free operation.
3. The method of claim 1 , wherein depositing the first metal layer and the second metal layer comprises conformal deposition.
4. The method of claim 1 , wherein the first epitaxy region includes at least one of germanium and silicon germanium.
5. The method of claim 1 , wherein the first metal layer includes at least one of ruthenium (Ru), cobalt (Co), nickel (Ni), platinum (Pt), and tungsten (W).
6. The method of claim 1 , further comprising forming a cap layer on the first epitaxy region and the second epitaxy region.
7. The method of claim 1 , wherein a work function of the first metal layer is greater than a work function of the second metal layer.
8. The method of claim 1 , further comprising, after depositing the second metal layer, annealing the first metal layer and the second metal layer to form a first silicide on the first epitaxy region and a second silicide on the second epitaxy region.
9. The method of claim 1 , further comprising removing the hydroxyl-sensitive agent by a baking operation or a plasma operation prior to depositing the second metal layer.
10. A method for manufacturing a semiconductor structure, comprising:
receiving a substrate having a first epitaxy region in a first transistor and a second epitaxy region in a second transistor, wherein the first epitaxy region has a first germanium concentration greater than 50%;
introducing a hydroxyl-sensitive agent directly onto the first epitaxy region and the second epitaxy region, wherein the hydroxyl-sensitive agent demonstrates different reactivities on the first epitaxy region and the second epitaxy region;
depositing a first metal layer, wherein the first metal layer covers the first epitaxy region and exposes a top surface of the second epitaxy region; and
depositing a second metal layer on the first epitaxy region and the second epitaxy region;
wherein the hydroxyl-sensitive agent is bonded to hydroxyl groups on a surface of the second epitaxy region; and
wherein the second epitaxy region comprises silicon phosphorus.
11. The method of claim 10 , wherein the second epitaxy region has a second germanium concentration less than that of the first epitaxy region.