Wet etch and clean chemistries for MoO
A method of removing non-noble metal oxides from material (e.g., semiconductor material) used to make a microelectronic device includes providing the material comprising traces of the conducting non-noble metal oxides; applying a chemical mixture (or chemical solution) to the material; removing the traces of the non-noble metal oxides from the material; and removing the chemical mixture from the material. The non-noble metal oxides comprise MoO x , wherein x is a positive number between 0 and 3. The chemical solution comprises any one of HNO 3 -based chemicals, H 2 SO 4 -based chemicals, HCl-based chemicals, or NH 4 OH-based chemicals.
1. A method of removing non-noble metal oxides from semiconductor substrate used to make a microelectronic device, said method comprising:
providing a semiconductor substrate comprising silicon oxide, silicon nitride, and traces of conducting non-noble metal oxides,
wherein said non-noble metal oxides comprise MoOx, (0<x≦3);
applying a chemical mixture to said semiconductor substrate,
wherein said chemical mixture comprises NH 4 OH,
wherein said chemical mixture selectively and completely removes said traces of said non-noble metal oxides from said semiconductor substrate while retaining the silicon oxide and the silicon nitride; and
removing said chemical mixture from said semiconductor substrate.
2. The method of claim 1 , wherein said chemical mixture further comprises H 2 O 2 and H 2 O.
3. The method of claim 1 , wherein the applying of said chemical mixture occurs in a temperature range of between 20° C. and 80° C.
4. The method of claim 1 , further comprising applying anyone of a patterned photoresist or hardmask over said semiconductor substrate prior to the applying of said chemical mixture.
5. The method of claim 1 , wherein removed said traces of said non-noble metal oxides remain in solution of said chemical mixture without re-attaching to said semiconductor substrate.
6. The method of claim 1 , wherein said removing said traces of said non-noble metal oxides from said semiconductor substrate comprises anyone of a wet etching process or a wet cleaning process.
7. The method of claim 1 , wherein said removing said traces of said non-noble metal oxides from said semiconductor substrate comprises removing said traces of said non-noble metal oxides from a silicon wafer.
8. The method of claim 1 , wherein said traces of said conducting non-noble metal oxides are also removed from a bevel of the semiconductor substrate.
9. The method of claim 1 , wherein the traces of the conducting non-noble metal oxides are removed from a top side of the semiconductor substrate.
10. The method of claim 1 , wherein applying the chemical mixture to said semiconductor substrate is performed while spinning the semiconductor substrate.
11. The method of claim 10 , wherein the chemical mixture is applied to a backside of the semiconductor substrate.
12. The method of claim 11 , wherein the chemical mixture does not contact a front side of the semiconductor substrate when the chemical mixture is applied to the semiconductor substrate.
13. The method of claim 1 , wherein the traces of the conducting non-noble metal oxides are removed from a bottom side of the semiconductor substrate.
14. The method of claim 2 , wherein composition of the chemical mixture is 1 part of NH 4 OH to 1 part of H 2 O 2 to 20 parts of H 2 O.
15. The method of claim 2 , wherein composition of the chemical mixture is 1 part of NH 4 OH to 1 part of H 2 O 2 to 5 parts of H 2 O.
16. The method of claim 2 , wherein composition of the chemical mixture is 1 part of NH 4 OH to 1 part of H 2 O 2 to 50 parts of H 2 O.
17. The method of claim 2 , wherein composition of the chemical mixture is 1 part of NH 4 OH to 4 part of H 2 O 2 to 20 parts of H 2 O.
18. The method of claim 1 , wherein applying of the chemical mixture is performed at a temperature of greater than 80° C.