Method and apparatus for transistor sidewall salicidation

1. A method for manufacturing a transistor, comprising:

providing the transistor having a substrate, an insulator on the substrate, a structure on the insulator having a structure sidewall, and a spacer covering a portion of the structure sidewall;

activating an exposed portion of the structure sidewall;

depositing a conformal layer of a metal or metal containing material on the exposed portion of the structure sidewall wherein depositing uses an electroless deposition process; and

annealing the metal or metal containing material to diffuse into the exposed portion of the structure sidewall to form a salicide.

2. The method as claimed in claim 1 wherein:

activating uses a first process and a first metal; and

depositing the conformal layer uses a second process different from the first process and a second metal different from the first metal.

3. The method as claimed in claim 1 further comprising:

pre-cleaning the structure before activation using a solution containing citric acid.

4. The method as claimed in claim 1 wherein:

depositing uses the metal or metal containing material selected from nickel, cobalt, phosphorous, boron, an alloy thereof, a compound thereof, and a combination thereof.

5. The method as claimed in claim 1 further comprising:

post-cleaning the structure after depositing using a solution containing citric acid.

6. The method as claimed in claim 1 wherein:

annealing is performed in an inert atmosphere or vacuum from about 400° C. to about 600° C. for one to two minutes.

7. A method for manufacturing a transistor, comprising:

providing the transistor having a substrate, an insulator on the substrate, a gate on the insulator including a gate electrode having a vertical structure sidewall, a spacer covering a portion of the vertical structure sidewall, and a source/drain on the insulator including a fin having a vertical structure sidewall;

activating an exposed portion of the gate including an exposed portion of the vertical structure sidewall of the gate electrode and the source/drain including the vertical structure sidewall of the fin wherein activating uses a surface activation process;

depositing a conformal layer of a metal or metal containing material on the gate including the exposed portion of the vertical structure sidewall of the gate electrode and the source/drain including the vertical structure sidewall of the fin, the depositing not depositing the metal or metal containing material on the spacer or the insulator wherein depositing the conformal layer uses an electroless deposition process; and

annealing the metal or metal containing material to form a salicide with the material of the gate including the exposed portion of the vertical structure sidewall of the gate electrode and the source/drain including the vertical structure sidewall of the fin to form a salicide.

8. The method as claimed in claim 7 further comprising:

pre-cleaning the transistor before activation using an acidic solution containing citric acid;

post-cleaning the transistor after activation using an about neutral solution containing citric acid and tetramethylammonium hydroxide.

9. The method as claimed in claim 7 wherein:

depositing uses electroless deposition of the metal or the metal containing material selected from nickel, cobalt, phosphorous, boron, an alloy thereof, a compound thereof, and a combination thereof in a base solution containing citric acid.

10. The method as claimed in claim 7 wherein:

depositing uses an electroless deposition process in a base solution; and

depositing uses an about neutral post-cleaning solution after electroless deposition using a base solution.

11. The method as claimed in claim 7 further comprising:

post-cleaning the structure after depositing using a solution containing citric acid.

12. The method as claimed in claim 7 wherein:

annealing is performed in an inert atmosphere or vacuum from about 400° C. to about 450° C. for one to two minutes.