Capacitively coupled hydrogen plasmas sustained by tailored voltage waveforms: excitation dynamics and ion flux asymmetry
Capacitively coupled hydrogen plasmas sustained by tailored voltage waveforms: excitation dynamics and ion flux asymmetry
复制标题
DOI：
10.1088/0963-0252/25/4/045019
复制
发表时间：
2016-07
影响因子：
3.8
通讯作者：
B. Bruneau;P. Diomede;D. J. Economou;S. Longo;T. Gans;D. O’Connell;A. Greb;E. Johnson;J. Booth
中科院分区：
文献类型：
--
作者：
B. Bruneau;P. Diomede;D. J. Economou;S. Longo;T. Gans;D. O’Connell;A. Greb;E. Johnson;J. Booth
平行板电容耦合等离子体在氢在相对较高的压力（~1托）的激励与定制的电压波形包含多达五个频率。预测的混合模型相结合的粒子在细胞中的模拟与蒙特卡罗碰撞和流体模型进行比较，相位分辨的光学发射光谱测量，产生的信息在这些放电的激发速率的动态。当用振幅不对称波形激发放电时，放电变得电不对称，在两个电极中的每一个处具有不同的离子能量。出乎意料的是，两个电极中的每一个的H2+通量的大差异是由不同的H3+能量引起的。当放电被激发与斜坡不对称波形，只有微弱的电不对称的放电观察。在这种情况下，由于在一个电极处的快速鞘膨胀而引起的电子功率吸收被由于强电场反转而在相对电极处的电子功率吸收平衡。
Parallel plate capacitively coupled plasmas in hydrogen at relatively high pressure (~1 Torr) are excited with tailored voltage waveforms containing up to five frequencies. Predictions of a hybrid model combining a particle-in-cell simulation with Monte Carlo collisions and a fluid model are compared to phase resolved optical emission spectroscopy measurements, yielding information on the dynamics of the excitation rate in these discharges. When the discharge is excited with amplitude asymmetric waveforms, the discharge becomes electrically asymmetric, with different ion energies at each of the two electrodes. Unexpectedly, large differences in the H2+ fluxes to each of the two electrodes are caused by the different H3+ energies. When the discharge is excited with slope asymmetric waveforms, only weak electrical asymmetry of the discharge is observed. In this case, electron power absorption due to fast sheath expansion at one electrode is balanced by electron power absorption at the opposite electrode due to a strong electric field reversal.