Patent ID: 9685346
Date: 2017-06-20
CPC Classifications: C23C,H01J,H01L

Claim:
1. A method of generating plasma in at least one remote plasma source (RPS), the method comprising: generating a first plasma by supplying at least one first process gas into a first RPS and applying a first energy having a first power at a first duty ratio, wherein the first energy is applied in the form of a first electromagnetic wave (EMW) having a first frequency; and generating a second plasma by supplying at least one second process gas into a second RPS and applying a second energy having a second power at a second duty ratio, wherein the second energy is applied in the form of a second EMW having a second frequency, wherein the supplying of the at least one first process gas into the first RPS and the applying of the first energy are performed independent of the supplying of the at least one second process gas into the second RPS and the applying of the second energy, the first EMW is applied during an on-off time period of the first EMW comprising an on time period during which the first EMW is turned on and an off time period during which the first EMW is turned off, the second EMW is applied during an on-off time period of the second EMW comprising an on time period during which the second EMW is turned on and an off time period during which the second EMW is turned off, and the on-off time period of the first EMW is equal in duration to the on-off time period of the second EMW, the first duty ratio is equal to the second duty ratio, and the on time period of the first EMW is concurrent with the off time period of the second EMW, the first EMW is applied as a continuous wave during the on time period of the first EMW and/or the second EMW is applied as a continuous wave during the on time period of the second EMW.