Precursors and methods for preparing silicon-containing films
Provided are certain liquid silicon precursors useful for the deposition of silicon-containing films, such as films comprising silicon, silicon nitride, silicon oxynitride, silicon dioxide, silicon carbide, carbon-doped silicon nitride, or carbon-doped silicon oxynitride. Also provided are methods for forming such films utilizing vapor deposition techniques.
1. A compound of Formula (I):
wherein each R 1 is independently selected from a group consisting of hydrogen, C 1 -C 4 alkyl, or a halogen atom selected from a group consisting of Cl, Br, and I, and wherein at least one R 1 is other than hydrogen.
2. The compound of claim 1 , wherein each R 1 is methyl.
3. The compound of claim 1 , wherein each R 1 is ethyl.
4. The compound of claim 1 , wherein each R 1 is a halogen atom selected from a group consisting of Cl, Br, and I.
5. A process for preparing a compound of Formula (I):
wherein each R 1 is independently selected from a group consisting of, C 1 -C 4 alkyl, or a halogen atom selected from a group consisting of Cl, Br, and I, wherein at least one R 1 is other than-hydrogen, which comprises the steps:
A. contacting a compound of the formula
with a compound of the formula M-R 3 , wherein M is lithium or potassium and R 3 is a C 1 -C 6 alkyl group, optionally containing a nitrogen atom, to provide a compound of Formula (II):
wherein each R 1 is independently selected from a group consisting of hydrogen, C 1 -C 4 alkyl, or a halide atom selected from a group consisting of Cl, Br, and I, and wherein R 2 is chosen from lithium or potassium; followed by
B. Reacting the compound of Formula (II) with a compound of the formula
wherein X is a halogen.
6. The process of claim 5 , wherein each R 1 is methyl.
7. The process of claim 5 , wherein the compound of the formula M-R 3 is selected from a group consisting of n-butyl lithium, methyl lithium, t-butyl lithium, lithium diisopropylamide, methyl potassium, and n-butyl potassium.
8. The process of claim 5 , wherein each R 1 is methyl, X is chloro, and M is lithium.
9. A method for depositing a silicon-containing film onto a surface of a microelectronic device, which comprises introducing at least one compound of Formula (I)
wherein each R 1 is independently selected from a group consisting of hydrogen, C 1 -C 4 alkyl, or a halogen atom selected from a group consisting of Cl, Br, and I, and wherein at least one R 1 is other than hydrogen,
to said surface in a reaction chamber, under vapor deposition conditions.
10. The method of claim 9 , wherein the silicon-containing film is silicon dioxide.
11. The method of claim 9 , wherein the silicon-containing film is silicon nitride.
12. The method of claim 9 , wherein the vapor deposition conditions are selected from a group consisting of chemical vapor deposition (CVD), atomic layer deposition (ALD), plasma-enhanced ALD (PEALD), plasma enhanced cyclical chemical vapor deposition (PECCVD), a flowable chemical vapor deposition (FCVD), a plasma-enhanced ALD-like process, or an ALD process with oxygen-containing reactants, a nitrogen-containing reactant, or a combination thereof.
13. The method of claim 10 , wherein the vapor deposition conditions comprise a temperature of about 150° C. to about 650° C., and a pulsing sequence comprising the steps:
(v) injection of precursor of Formula (I) for 0.1 to 30 seconds, followed by
(vi) purging for 1 to 30 seconds using an inert gas, followed by
(vii) injection of ozone at a flow rate of 50 to 500 secm, for about 0.1 to 30 seconds, followed by
(viii) purging for 1 to 30 seconds using an inert gas, and repeating steps (i) through (iv) until a film of desired thickness has been obtained.
14. The method of claim 13 , wherein the compound of Formula (I) is bis(dimethylsilyl)dimethylhydrazine.
15. The method of claim 13 , wherein the temperature is about 500 to 550° C.