Substrate processing method, method for manufacturing semiconducor device, and plasma processing apparatus
A substrate processing method includes: providing a substrate including a first region and a second region into a chamber; forming a deposit film on the first region and the second region of the substrate by generating a first plasma from a first processing gas, and selectively etching the first region with respect to the second region by generating a second plasma from the second processing gas containing an inert gas. The first processing gas is a mixed gas including a first gas containing carbon atoms and fluorine atoms and a second gas containing silicon atoms.
1. A method for processing a substrate comprising:
(a) providing a substrate including a first region and a second region into a chamber;
(b) forming a deposit film on the first region and the second region of the substrate by generating a first plasma from a first processing gas; and
(c) etching the first region by generating a second plasma from a second processing gas containing an inert gas,
wherein the first processing gas is a mixed gas including a first gas containing carbon atoms and fluorine atoms and a second gas containing silicon atoms.
2. The method according to claim 1 , wherein the deposit film contains carbon atoms and fluorine atoms, and
in (b), a composition ratio of the carbon atoms and the fluorine atoms in the deposit film formed on each of the first region and the second region is controlled by adjusting a flow rate ratio of the first gas and the second gas.
3. The method according to claim 2 , wherein the ratio of the composition ratio of the carbon atoms to the composition ratio of the fluorine atoms in the deposit film is increased b increasing the flow rate ratio of the second gas to the first gas.
4. The method according to claim 1 , wherein the first gas is at least one of a fluorocarbon gas and a hydrofluorocarbon gas.
5. The method according to claim 1 , wherein the first gas contains at least one selected from a group consisting of C 5 F 8 gas, C 5 F 8 gas, C 4 F 8 gas, C 4 F 6 gas, CF 4 gas, CH 3 F gas, CHF 3 gas, and CH 2 F 2 gas.
6. The method according to claim 1 , wherein the second gas contains at least one selected from a group consisting of SiCl 4 gas, SiH 4 gas, Si 2 H 6 gas, SiH 2 C 12 gas, Si 4 H 10 gas, and Si 5 H 12 gas.
7. The method according to claim 1 , wherein the first region contains silicon oxide, and the second region contains silicon nitride.
8. The method according to claim 7 , wherein, in (c), the first region is etched by reacting the first region with ions contained in the second plasma.
9. The method according to claim 1 , wherein the second processing gas is a rare gas or a nitrogen gas.
10. The method according to claim 1 , wherein a cycle including (b) and (c) is repeated once or more times.
11. The method according to claim 10 , wherein the flow rate of the second gas is gradually increased or decreased as the cycle is repeated.
12. The method according to claim 10 , wherein the flow rate of the second gas is gradually decreased as the cycle is repeated.
13. The method according to claim 1 , wherein a proportion occupied by a processing time of (b) in a total of a processing time of (b) and (c) is set to a range of 5% to 45%.
14. A method for processing a substrate comprising:
(a) providing a substrate including a first region and a second region into a chamber; and
(b) forming a deposit film on the first region and the second region of the substrate by generating a first plasma from a first processing gas,
wherein the first processing gas is a mixed gas including a first gas containing carbon atoms and fluorine atoms and a second gas containing silicon atoms.
15. A method for manufacturing a semiconductor device including the substrate processing method according to claim 1 .