Method of manufacturing semiconductor device and method of processing substrate
Provided is a method of forming a tantalum oxide-based film having good step coverage while controlling an oxygen concentration in the film. The method includes forming a tantalum nitride layer on a substrate by supplying a source gas including a tantalum and a nitriding agent into a process chamber wherein the substrate is accommodated under a condition where a chemical vapor deposition (CVD) reaction is caused; oxidizing the tantalum nitride layer by supplying an oxidizing agent into the process chamber under a condition where an oxidation reaction of the tantalum nitride layer by the oxidizing agent is unsaturated; and forming on the substrate a conductive tantalum oxynitride film wherein an oxygen is stoichiometrically insufficient with respect to the tantalum and a nitrogen by alternately repeating forming the tantalum nitride layer on the substrate and oxidizing the tantalum nitride layer a plurality of times.
1. A method of manufacturing a semiconductor device, comprising:
(a) forming on a substrate a conductive tantalum oxide film wherein oxygen is stoichiometrically insufficient with respect to tantalum by alternately repeating: supplying a source gas including the tantalum and a nitriding agent into a process chamber wherein the substrate is accommodated under a condition where a chemical vapor deposition (CVD) reaction is caused to form a tantalum nitride layer on the substrate; and supplying an oxidizing agent into the process chamber to oxidize the tantalum nitride layer under a condition where an oxidation reaction of the tantalum nitride layer by the oxidizing agent is unsaturated while removing nitrogen from the tantalum nitride layer;
(b) supplying the source gas including the tantalum and the oxidizing agent into the process chamber with the substrate having the conductive tantalum oxide film formed thereon being accommodated in the process chamber after performing the step (a) to form an insulating tantalum oxide film on the conductive tantalum oxide film; and
(c) unloading the substrate having the conductive tantalum oxide film and the insulating tantalum oxide film formed thereon from the process chamber.
2. The method according to claim 1 , wherein the source gas comprises a butyl imino group.
3. The method according to claim 1 , wherein the source gas comprises a tertiary butyl imino group.
4. The method according to claim 2 , wherein the source gas further comprises at least one of an ethyl group and a methyl group, and an amino group.
5. The method according to claim 3 , wherein the source gas further comprises at least one of an ethyl group and a methyl group, and an amino group.
6. The method according to claim 1 , wherein the source gas comprises at least one of Ta[NC(CH 3 ) 3 ][N(C 2 H 5 ) 2 ] 3 , Ta[NC(CH 3 ) 3 ][N(C 2 H 5 )CH 3 ] 3 and Ta[NC(CH 3 ) 3 ][N(CH 3 ) 2 ] 3 .
7. The method according to claim 6 , wherein the nitriding agent comprises at least one of NH 3 , N 2 H 2 , N 2 H 4 and N 3 H 8 , and the oxidizing agent comprises at least one of O 2 , O 3 , H 2 O and O 2 +H 2 .
8. The method according to claim 1 , wherein the insulating tantalum oxide film is continuously formed on the conductive tantalum oxide film in the process chamber after forming the conductive tantalum oxide film in the step (a) without unloading the substrate from the process chamber.
9. The method according to claim 1 , wherein the conductive tantalum oxide film and the insulating tantalum oxide film are continuously formed in the process chamber.
10. The method according to claim 1 , wherein the conductive tantalum oxide film and the insulating tantalum oxide film are continuously formed in-situ.
11. The method according to claim 1 , wherein the oxidizing agent comprises O 2 +H 2 .
12. The method according to claim 1 , wherein the oxidizing agent comprises O 3 .
13. The method according to claim 1 , wherein further comprising exposing the substrate to an atmosphere after the conductive tantalum oxide film and the insulating tantalum oxide film are formed.
14. The method according to claim 13 , wherein the insulating tantalum oxide film serves as a barrier layer preventing the conductive tantalum oxide film from being exposed to the atmosphere when the substrate is exposed to the atmosphere.