Deposition of amorphous silicon-containing films
View Patent ↗Chemical vapor deposition methods are used to deposit amorphous silicon-containing films over various substrates. Such methods are useful in semiconductor manufacturing to provide a variety of advantages, including uniform deposition over heterogeneous surfaces, high deposition rates, and higher manufacturing productivity. Preferably, the deposited amorphous silicon-containing film is annealed to produce crystalline regions over all or part of an underlying substrate.
1. A deposition method comprising:
depositing an amorphous Si-containing film onto an exposed single crystal surface of a mixed substrate at a rate of about 20 Å per minute or higher using a feed gas that comprises trisilane, wherein the amorphous Si-containing film has a thickness non-uniformity that is about 20% or less across its surface over the mixed substrate; and
annealing the amorphous Si-containing film to form a crystalline Si-containing film that comprises a single crystal region.
2. The method of claim 1 in which the crystalline Si-containing film is an epitaxial crystalline film.
3. The method of claim 1 in which the crystalline Si-containing film further comprises a polycrystalline region.
4. The method of claim 1 in which the depositing is conducted at a temperature in the range of about 350° C. to about 500° C.
5. The method of claim 1 in which the annealing is conducted at a temperature in the range of about 500° C. to about 1100° C.
6. The method of claim 1 in which the depositing is conducted at a temperature in the range of about 350° C. to about 500° C. and the annealing is conducted at a temperature in the range of about 500° C. to about 750° C.
7. The method of claim 6 in which the substrate is crystalline.
8. The method of claim 1 in which the crystalline Si-containing film is selected from the group consisting of silicon, doped silicon, SiC, doped SiC, SiGe, doped SiGe, SiGeC, and doped SiGeC.
9. The method of claim 1 , further comprising depositing a SiGe film onto the crystalline Si-containing film.
10. The method of claim 9 in which the SiGe film comprises a dopant.
11. The method of claim 1 in which the feed gas further comprises a precursor selected from the group consisting of a germanium source, a silicon source, a carbon source, a boron source, a gallium source, an indium source, an arsenic source, a phosphorous source, an antimony source, a nitrogen source and an oxygen source.
12. The method of claim 11 in which the precursor is a silicon source selected from the group consisting of silane and disilane.
13. The method of claim 1 , wherein the mixed substrate comprises the single crystal surface and a surface that is not single crystal.
14. The method of claim 1 , wherein the mixed substrate comprises a surface that is epitaxial and a surface that is not epitaxial.
15. The method of claim 1 , wherein the mixed substrate comprises a surface that is amorphous and a surface that is not amorphous.
16. The method of claim 1 , wherein the thickness non-uniformity is about 15% or less.
17. The method of claim 1 , wherein thickness non-uniformity is about 10% or less.
18. The method of claim 1 , wherein the thickness non-uniformity is about 8% or less.
19. The method of claim 1 , wherein the thickness non-uniformity is about 6% or less.
20. The method of claim 1 , wherein the thickness non-uniformity is about 4% or less.
21. The method of claim 1 , wherein the rate is about 50 Å per minute or higher.
22. The method of claim 1 , wherein the depositing occurs in a chamber, and the chamber comprises a total pressure in the range of about 1 Torr to about 350 Torr.
23. The method of claim 1 , wherein the depositing occurs in a chamber, and the chamber comprises a total pressure in the range of about 1 Torr to about 100 Torr.
24. The method of claim 22 , wherein trisilane comprises a partial pressure in the range of about 0.0001% to about 100% of the total pressure in the chamber.
25. The method of claim 22 , wherein trisilane comprises a partial pressure in the range of about 0.001% to about 50% of the total pressure in the chamber.