Selective growth of metal-containing hardmask thin films
Methods and apparatuses for selectively growing metal-containing hard masks are provided herein. Methods include providing a substrate having a pattern of spaced apart features, each feature having a top horizontal surface, filling spaces between the spaced apart features with carbon-containing material to form a planar surface having the top horizontal surfaces of the features and carbon-containing material, selectively depositing a metal-containing hard mask on the top horizontal surfaces of the features relative to the carbon-containing material, and selectively removing the carbon-containing material relative to the metal-containing hard mask and features.
1. A method comprising:
providing a patterned semiconductor substrate having features spaced apart on an underlying material to be etched;
filling spaces between the features with an ashable fill such that top horizontal surfaces of the features are exposed and sidewalls of the features contact the ashable fill;
after filling the spaces between the features, selectively depositing a metal-containing hard mask on the exposed top horizontal surfaces of the features relative to the ashable fill; and
removing the ashable fill relative to the features and metal-containing hard mask.
2. The method of claim 1 , wherein the filling between the features is performed to form a planar surface comprising the top horizontal surfaces of the features and the ashable fill.
3. The method of claim 1 , wherein the filling between the features is done by spin-on.
4. The method of claim 3 , wherein the spin-on is performed by injecting a carbon-containing fluid mixture onto the patterned semiconductor substrate followed by heat curing.
5. The method of claim 3 , wherein the filling between the features is done by spin-on followed by planarization to expose the top horizontal surfaces of the features.
6. The method of claim 1 , wherein the filling between the features is done by plasma enhanced chemical vapor deposition.
7. The method of claim 6 , wherein the filling between the features further comprises planarizing the patterned semiconductor substrate after the plasma enhanced chemical vapor deposition.
8. The method of claim 6 , wherein the filling by plasma enhanced chemical vapor deposition comprises exposing the features to a hydrocarbon precursor having a formula C x H y , wherein X is an integer between and including 2 and 10, and Y is an integer between and including 2 and 24.
9. The method of claim 1 , wherein the selectively depositing of the metal-containing hard mask is performed at a substrate temperature between about 200° C. and about 400° C.
10. The method of claim 1 , wherein the selectively depositing of the metal-containing hard mask is performed by one or more cycles of atomic layer deposition.
11. The method of claim 10 , wherein one cycle of atomic layer deposition comprises exposure to a silicon-containing precursor and exposure to a tungsten-containing precursor.
12. The method of claim 11 , wherein the silicon-containing precursor is silane.
13. The method of claim 11 , wherein the tungsten-containing precursor is a tungsten halide.
14. The method of claim 13 , wherein the tungsten-containing precursor is selected from the group consisting of tungsten hexafluoride, tungsten pentachloride, tungsten hexachloride, and combinations thereof.
15. The method of claim 1 , wherein the features comprise a dielectric material.
16. The method of claim 1 , wherein the features comprise silicon.
17. The method of claim 1 , wherein the metal-containing hard mask comprises tungsten.
18. The method of claim 17 , wherein the metal-containing hard mask is selected from the group consisting of tungsten, tungsten carbide, tungsten carbonitride, and combinations thereof.
19. The method of claim 1 , wherein spaces between features have an aspect ratio of at least about 4:1.