Substrate processing method and substrate processing apparatus

1 . A substrate processing method for processing a substrate in a processing vessel, comprising:

(a) heating the substrate to a set processing temperature;

(b) supplying deuterium into the processing vessel;

(c) supplying oxygen into the processing vessel; and

(d) discharging the deuterium and the oxygen in the processing vessel so that a pressure inside the processing vessel maintains a set processing pressure,

wherein, at a start of the processing of the substrate, the step (b) is started first so that the pressure inside the processing vessel becomes stable at a pressure that corresponds to opening degree of a pressure regulating valve of the processing vessel,

wherein the step (a) is started after the pressure inside the processing vessel becomes stable by step (b) at the pressure that corresponds to opening degree of the pressure regulating valve of the processing vessel,

wherein the step (c) is started, after the step (b) is started, when the pressure inside the processing vessel becomes stable at the pressure that corresponds to opening degree of a pressure regulating valve of the processing vessel, and

wherein the step (d) is performed after the step (c) is started, and the step (b) and the step (c) are continuingly performed while the step (d) is performed.

2 . The substrate processing method according to claim 1 , wherein a timing to start the step (c) is timing at which the processing temperature is reached by heating the substrate in the step (a).

3 . The substrate processing method according to claim 1 , wherein, in the step (a), the processing temperature is set to a temperature in a range from 500° C. to 700° C.

4 . The substrate processing method according to claim 1 , wherein, in the step (d), the processing pressure is set to lower than or equal to 1 Torr.

5 . The substrate processing method according to claim 1 ,

wherein a ratio of a flow rate of the deuterium flowed in the step (b) to a flow rate of the oxygen supplied in the step (c) is in a range from twice to 20 times.

6 . The substrate processing method according to claim 1 , wherein the substrate includes an insulating film formed on a surface of the substrate, and the deuterium is incorporated into the insulating film by the processing of the substrate.

7 . The substrate processing method according to claim 1 , wherein the substrate includes an insulating film comprising silicon nitride or a high-k dielectric, and the method includes incorporating the deuterium into the insulating film and reducing a leakage current of the insulating film.