CVD precursors
View Patent ↗A method of producing silicon containing thin films by the thermal polymerization of a reactive gas mixture bisaminosilacyclobutane and source gas selected from a nitrogen providing gas, an oxygen providing gas and mixtures thereof. The films deposited may be silicon nitride, silicon carbonitride, silicon dioxide or carbon doped silicon dioxide. These films are useful as dielectrics, passivation coatings, barrier coatings, spacers, liners and/or stressors in semiconductor devices.
1. A method for producing silicon containing films on a substrate wherein the method comprises the thermal or plasma polymerization of a reactive gas mixture comprising bisaminosilacyclobutane and source gas selected from a nitrogen providing gas, an oxygen providing gas and mixtures thereof, wherein the film deposited is a silicon carbonitride film, and wherein the bisaminosilacyclobutane is represented by:
where each R 1 , R 2 , R 3 , and R 4 is selected from hydrogen and a monovalent hydrocarbon group having 1 to 6 carbons, where R 1 and R 2 together may optionally form a cyclic group including N and/or R 3 and R 4 together may optionally form a cyclic group including N; and
where the thermal or plasma polymerization is carried out at a temperature of from 25 to 500° C.
2. The method as claimed in claim 1 wherein the bisaminosilacyclobutane is selected from Bis(t-butylamino)silacyclobutane, Bis(i-propylamino)silacyclobutane, Bis(ethylamino)silacyclobutane, Bis(methylamino)silacyclobutane, Bis(pyrrolidino)silacyclobutane, Bis(dimethylamino)silacyclobutane, and Bis(diethylamino)silacyclobutane.
3. The method as claimed in claim 1 wherein the source gas is a nitrogen providing gas selected from nitrogen N 2 , ammonia NH 3 , hydrazine N 2 H 4 , hydrazoic acid HN 3 , and mixtures thereof.
4. The method as claimed in claim 3 wherein there is 0.1 to 50 volume parts of nitrogen providing gas per volume part of bisaminosilacyclobutane.
5. The method as claimed in claim 4 wherein there is 0.2 to 7 volume parts of nitrogen providing gas per volume part bisaminosilacyclobutane.
6. The method as claimed in claim 3 wherein the source gas is ammonia.
7. The method as claimed in claim 1 wherein there is also present a material selected from carrier gases, dopants, halogens and halogen-containing gases.
8. The method as claimed in claim 1 wherein the substrate is a semiconductor substrate.
9. The method as claimed in claim 1 wherein the polymerization comprises thermal polymerization and is carried out by low pressure chemical vapor deposition or by atomic layer deposition.
10. The method as claimed in claim 1 wherein the film deposited has a thickness of 0.01 to 10 μm.
11. The method as claimed in claim 1 wherein the polymerization comprises plasma polymerization and is carried out by plasma enhanced chemical vapor deposition or by plasma enhanced atomic layer deposition.