CVD Mo deposition by using MoOCl
A method of forming a molybdenum-containing material on a substrate is described, in which the substrate is contacted with molybdenum oxytetrachloride (MoOCl 4 ) vapor under vapor deposition conditions, to deposit the molybdenum-containing material on the substrate. In various implementations, a diborane contact of the substrate may be employed to establish favorable nucleation conditions for the subsequent bulk deposition of molybdenum, e.g., by chemical vapor deposition (CVD) techniques such as pulsed CVD.
1. A method of forming a molybdenum-containing material on a substrate, comprising establishing a nucleation surface on the substrate by contacting the substrate with vapor consisting of diborane vapor and optionally separately with molybdenum oxytetrachloride (MoOCl 4 ) vapor and contacting the nucleation surface of the substrate with molybdenum oxytetrachloride (MoOCl 4 ) vapor under vapor deposition conditions, to deposit the molybdenum-containing material on the substrate.
2. The method of claim 1 , wherein establishing the nucleation surface comprises a plurality of cycles of contacting the substrate with vapor consisting of diborane vapor and separately with molybdenum oxytetrachloride (MoOCl 4 ) vapor.
3. The method of claim 1 , wherein the contact of the substrate with vapor consisting of diborane vapor is conducted at temperature in a range of from 300° C. to 450° C.
4. The method of claim 1 , wherein the vapor deposition conditions are pulsed vapor deposition conditions.
5. The method of claim 1 , wherein the vapor conditions are selected such that the deposited molybdenum-containing material has a resistivity of at most 20 μΩ·cm.
6. The method of claim 1 , wherein the molybdenum-containing material is deposited at a temperature in the range of from 400° C. to 600° C.
7. The method of claim 1 , comprising volatilizing molybdenum oxytetrachloride (MoOCl 4 ) to form said molybdenum oxytetrachloride (MoOCl 4 ) vapor.
8. The method of claim 1 , wherein said vapor deposition conditions comprise a reducing ambient so that the molybdenum-containing material comprises elemental molybdenum material.
9. The method of claim 1 , wherein the molybdenum-containing material comprises molybdenum oxide.
10. The method of claim 1 , wherein the substrate comprises one or more of TiN, Mo, MoC, B, SiO 2 , W, and WCN.
11. The method of claim 1 , wherein: the substrate comprises a semiconductor device substrate comprising silicon dioxide having a titanium nitride layer thereon; the method comprises forming a nucleation surface on the titanium nitride layer; and the molybdenum-containing material is deposited on the nucleation layer.
12. The method of claim 11 , wherein the nucleation surface is formed by pulsed CVD or ALD deposition comprising contact of the titanium nitride layer with diborane vapor and separately with molybdenum oxytetrachloride (MoOCl 4 ) vapor.
13. The method of claim 1 carried out in a process for making a semiconductor device on the substrate.
14. The method of claim 13 , wherein the semiconductor device comprises at least one of a DRAM device and a 3-D NAND device.
15. The method of claim 1 , wherein the substrate comprises a via in which the molybdenum-containing material is deposited.
16. The method of claim 1 , wherein the molybdenum-containing material is deposited on the substrate at step coverage of from 90% to 110%.
17. A method of forming a molybdenum-containing material on a semiconductor device substrate comprising silicon dioxide having a titanium nitride layer thereon, the method comprising: forming a nucleation surface on the titanium nitride layer by contacting the titanium nitride layer with vapor consisting of diborane vapor, contacting the nucleation surface with molybdenum oxytetrachloride (MoOCl 4 ) vapor under vapor deposition conditions, to deposit the molybdenum-containing material on the substrate, wherein the vapor conditions are selected such that the deposited molybdenum-containing material has a resistivity of at most 20 μΩ·cm.