Substrate processing method
A substrate processing method includes steps of: arranging a substrate in a chamber; introducing H 2 gas at a first flow rate and O 2 gas at a second flow rate independently from the H 2 gas into a catalyst reaction portion in which catalyst is accommodated, wherein H 2 O gas produced from the H 2 gas and the O 2 gas that contact the catalyst is ejected from the catalyst reaction portion toward the substrate; and reducing a flow rate of the O 2 gas introduced to the catalyst reaction portion to a third flow rate that is lower than the second flow rate, wherein the steps of introducing the H 2 gas and the O 2 gas and reducing the flow rate of the O 2 gas are repeated in this order at a predetermined repetition frequency, thereby processing the substrate.
1. A substrate processing method of processing a substrate, the method comprising steps of:
arranging a substrate in a chamber;
introducing H 2 gas at a first flow rate and O 2 gas at a second flow rate independently from the H 2 gas into a catalyst reaction portion in which a catalyst is accommodated, wherein H 2 O gas produced from the H 2 gas and the O 2 gas that contact the catalyst is ejected from the catalyst reaction portion toward the substrate; and
reducing a flow rate of the O 2 gas introduced to the catalyst reaction portion to a third flow rate that is lower than the second flow rate,
wherein the steps of introducing the H 2 gas and the O 2 gas and reducing the flow rate of the O 2 gas are repeated in this order at a predetermined repetition frequency, thereby processing the substrate.
2. The substrate processing method of claim 1 , further comprising a step of supplying a film deposition gas including a constituent element of an oxide film into the chamber for a predetermined period of time,
wherein repetition at the predetermined repetition frequency is carried out in the order of the steps of introducing the H 2 gas and the O 2 gas, supplying the film deposition gas, and reducing the flow rate of the O 2 gas.
3. The substrate processing method of claim 2 , wherein the third flow rate in the step of reducing the flow rate of the O 2 gas is 0 sccm.
4. The substrate processing method of claim 2 , further comprising a step of reducing a flow rate of the H 2 gas introduced to the catalyst reaction portion to a fourth flow rate that is lower than the first flow rate.
5. The substrate processing method of claim 4 , wherein the third flow rate in the step of reducing the flow rate of the O 2 gas is 0 sccm, and
wherein the fourth flow rate in the step of reducing the flow rate of the H 2 gas is 0 sccm.
6. The substrate processing method of claim 5 , wherein the step of reducing the flow rate of the H 2 gas is carried out after the step of reducing the flow rate of the O 2 gas.
7. The substrate processing method of claim 2 , wherein the step of introducing the H 2 gas and the O 2 gas includes a step of setting a partial pressure of the O 2 gas in the catalyst reaction portion to a first partial pressure, and
wherein the step of reducing the flow rate of the O 2 gas includes a step of setting a partial pressure of the O 2 gas in the catalyst reaction portion to a second partial pressure that is lower than the first partial pressure.
8. The substrate processing method of claim 2 , wherein the H 2 gas is introduced into the catalyst reaction portion earlier than the O 2 gas in the step of introducing the H 2 gas and the O 2 gas.
9. The substrate processing method of claim 2 , wherein the predetermined repetition frequency is in a range from 1 Hz through 1 kHz.
10. The substrate processing method of claim 2 , wherein the predetermined period of time is 1 second or less.
11. The substrate processing method of claim 1 , further comprising:
a step of reducing a flow rate of the H 2 gas introduced to the catalyst reaction portion to a fourth flow rate that is lower than the first flow rate; and
a step of supplying a film deposition gas including a constituent element of an oxide film into the chamber for a predetermined period of time,
wherein the step of supplying the film deposition gas is carried out after the step of introducing the H 2 gas and the O 2 gas is started and after the steps of reducing the flow rate of the O 2 gas and reducing the flow rate of the H 2 gas, and
wherein the repetition at the predetermined repetition frequency is carried out in the order of the step of introducing the H 2 gas and the O 2 , the steps of reducing the flow rate of the O 2 gas and reducing the flow rate of the H 2 gas, and the step of supplying the film deposition gas.
12. The substrate processing method of claim 1 , wherein the third flow rate in the step of reducing the flow rate of the O 2 gas is 0 sccm.
13. The substrate processing method of claim 1 , further comprising a step of reducing a flow rate of the H 2 gas introduced to the catalyst reaction portion to a fourth flow rate that is lower than the first flow rate.
14. The substrate processing method of claim 13 , wherein the third flow rate in the step of reducing the flow rate of the O 2 gas is 0 sccm, and
wherein the fourth flow rate in the step of reducing the flow rate of the H 2 gas is 0 sccm.
15. The substrate processing method of claim 14 , wherein the step of reducing the flow rate of the H 2 gas is carried out after the step of reducing the flow rate of the O 2 gas.
16. The substrate processing method of claim 1 , wherein the step of introducing the H 2 gas and the O 2 gas includes a step of setting a partial pressure of the O 2 gas in the catalyst reaction portion to a first partial pressure, and
wherein the step of reducing the flow rate of the O 2 gas includes a step of setting a partial pressure of the O 2 gas in the catalyst reaction portion to a second partial pressure that is lower than the first partial pressure.
17. The substrate processing method of claim 1 , wherein the H 2 gas is introduced into the catalyst reaction portion earlier than the O 2 gas in the step of introducing the H 2 gas and the O 2 gas.
18. The substrate processing method of claim 1 , wherein the predetermined repetition frequency is in a range from 1 Hz through 1 kHz.