Dual silicide integration with laser annealing
View Patent ↗The embodiments of the present invention relate generally to the fabrication of integrated circuits, and more particularly to a structure and method for fabricating more particularly to a structure and method for fabricating silicides with different compositions and/or thicknesses on a single structure having more than one type of device using laser annealing. A method is disclosed that includes using a photoresist compatible with a laser annealing process to protect a region of a semiconductor substrate from silicide formation.
1. A method comprising:
forming a first photoresist layer over a first device formed on a semiconductor substrate;
forming a metal layer over a second device formed on the semiconductor substrate and the first photoresist layer;
performing an annealing process to form a first silicide on a source-drain region of the second device;
removing unreacted portions of the first metal layer after performing the annealing process;
removing the first photoresist layer;
forming a second metal layer on the first device and the second device;
performing an annealing process to form a second silicide on a source-drain region of the first device, wherein the annealing process to form the second silicide comprising:
performing a first anneal within a first temperature range;
removing unreacted portions of the second metal layer; and
performing a second anneal within a second temperature range.
2. The method of claim 1 , wherein the first photoresist layer comprises:
a resist material able to withstand a post-exposure bake (PEB) temperature ranging from approximately 70° C. to approximately 115° C. for approximately 60 seconds.
3. The method of claim 1 , wherein the performing an annealing process to form the first silicide on the source-drain region of the second device comprises performing a laser annealing process.
4. The method of claim 1 , wherein performing an annealing process to form the first silicide on the source-drain region of the second device comprises:
performing a first anneal within a first temperature range;
removing unreacted portions of the first metal layer; and
performing a second anneal within a second temperature range.
5. The method of claim 1 , wherein the performing the annealing process to form the second silicide on the source-drain region of the first device comprises a laser annealing process.
6. The method of claim 1 , further comprising:
forming a second photoresist layer over the second device and the first silicide before forming the second metal layer on the first device and the second device, the second photoresist layer comprising a resist able to withstand a post-exposure bake (PEB) temperature ranging from approximately 70° C. to approximately 115° C. for approximately 60 seconds.
7. The method of claim 1 , wherein the forming the second silicide on the source-drain region of the first device changes the composition of the first silicide.
8. The method of claim 1 , wherein the second silicide has a different thickness than the first silicide.