Abnormal heating of low-energy electrons in low-pressure capacitively coupled discharges

作者：Park G Y^*; You S J; Iza F; Lee J K

来源：Physical Review Letters, 2007, 98(8): 085003.

DOI：10.1103/PhysRevLett.98.085003

In low-pressure capacitively coupled plasmas, high-energy electrons are collisionlessly heated by large rf fields in the sheaths while low-energy electrons are confined in the bulk plasma by the ambipolar potential. Low-energy electrons are typically inefficiently heated due to their low collisionality and the weak rf electric field present in the bulk. It is shown, however, that as a result of the nonlinear interaction between the electron motion and the weak rf field present in the bulk, low-energy electrons can be efficiently heated. Electrons in the bulk that bounce inside the electrostatic potential well with a frequency equal to the rf excitation frequency are efficiently heated by the coherent interaction with the rf field. This resonant collisionless heating can be very efficient and manifest itself as a plateau in the electron energy probability function.

• 出版日期2007-2-23