Method of cleaning, method of manufacturing semiconductor device, substrate processing apparatus, and recording medium
A method of cleaning an interior of a process chamber by supplying a cleaning gas into the process chamber after a process of forming a thin film on a substrate in the process chamber is performed, including alternately repeating changing a pressure in the process chamber from a first pressure range to a second pressure range, and changing the pressure in the process chamber from the second pressure range to the first pressure range. In this method, when the pressure in the process chamber is changed to the first pressure range, the pressure in the process chamber is changed to the first pressure range without being maintained at the second pressure range, and when the pressure in the process chamber is changed to the second pressure range, the pressure in the process chamber is changed to the second pressure range without being maintained at the first pressure range.
1. A method of cleaning an interior of a process chamber by supplying a cleaning gas into the process chamber after a process of forming a thin film on a substrate in the process chamber is performed, the method comprising:
alternately repeating, in a state where supplying the cleaning gas into the process chamber is maintained, changing a pressure in the process chamber from a first pressure range to a second pressure range, and changing the pressure in the process chamber from the second pressure range to the first pressure range,
wherein in the act of alternately repeating the acts of changing the pressure in the process chamber, when the pressure in the process chamber is changed to the first pressure range after being changed to the second pressure range, the pressure in the process chamber is changed to the first pressure range without being maintained at the second pressure range, and when the pressure in the process chamber is changed to the second pressure range after being changed to the first pressure range, the pressure in the process chamber is changed to the second pressure range without being maintained at the first pressure range,
wherein a low pressure range is a lower one of the first pressure range and the second pressure range and a high pressure range is a higher one of the first pressure range and the second pressure range, and
wherein in the act of alternately repeating the acts of changing the pressure in the process chamber, a pressure falling time period which occurs until the pressure in the process chamber reaches the low pressure range from the high pressure range is set to be longer than a pressure rising time period which occurs until the pressure in the process chamber reaches the high pressure range from the low pressure range.
2. The method according to claim 1 , wherein the act of alternately repeating the acts of changing the pressure in the process chamber is performed under a non-plasma atmosphere.
3. The method according to claim 1 , wherein in the act of alternately repeating the acts of changing the pressure in the process chamber, deposits including the thin film deposited on a surface of a member in the process chamber are removed by a thermochemical reaction.
4. The method according to claim 1 , wherein the first pressure range is from 13 to 2,660 Pa and the second pressure range is from 5,320 to 13,300 Pa.
5. The method according to claim 1 , wherein in the act of alternately repeating the acts of changing the pressure in the process chamber, a temperature in the process chamber is set to be not lower than room temperature and not higher than 200 degrees C.
6. The method according to claim 1 , wherein the cleaning gas includes a fluorine-based gas.
7. The method according to claim 1 , wherein the cleaning gas includes at least one selected from a group consisting of hydrogen fluoride gas, fluorine gas, nitrogen fluoride gas, and chlorine fluoride gas.
8. The method according to claim 1 , wherein the cleaning gas includes a hydrogen fluoride gas.