Electron power absorption dynamics in magnetized capacitively coupled radio frequency oxygen discharges
Electron power absorption dynamics in magnetized capacitively coupled radio frequency oxygen discharges
复制标题
磁化电容耦合射频氧气放电中的电子功率吸收动力学
DOI：
10.1088/1361-6595/abb2e7
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发表时间：
2020-10
影响因子：
3.8
通讯作者：
Julian Schulze
中科院分区：
文献类型：
--
作者：
Li Wang;De-Qi Wen;Perter Hartmann;Zoltan Donko;Aranka Dersi;Xi-Feng Wang;Yuan-Hong Song;You-Nian Wang;Julian Schulze
采用一维粒子模拟/蒙特卡罗碰撞（1D PIC/MCC）方法研究了平行于电极的均匀磁场对100 mTorr、13.56 MHz频率下射频电容耦合氧放电的影响.增加从0到200 G的磁场被发现，导致在一个急剧增强的电子和O2+离子的密度，由于由磁场增强的电子约束。然而，时空平均的O−离子密度几乎保持不变，因为解离电子附着（O−的产生通道）和由于负离子与氧离子碰撞而产生的缔合电子脱离速率（O−的主要损失通道）同时增强。这是理解的基础上的时空电子动力学的详细分析。几乎恒定的O−密度与增加的电子密度一起导致电负性的显着降低和作为外部施加磁场的函数的电子功率吸收动力学的显着变化。当磁场较低时，放电模式为电负性漂移双极模式，而当磁场增加时，放电模式转变为电正性α模式。同时，在强磁场下，鞘层局部塌陷时，在每个电极附近产生强电场反转，局部增强了电子功率吸收。电场产生的模型揭示了反向电场是由于磁场捕获到电极的电子通量减少而引起的。等离子体性质的随之而来的变化预计会影响这种放电在蚀刻，沉积和其他半导体加工技术中的应用。
The influence of a uniform magnetic field parallel to the electrodes on radio frequency capacitively coupled oxygen discharges driven at 13.56 MHz at a pressure of 100 mTorr is investigated by one-dimensional particle-in-cell/Monte Carlo collision (1D PIC/MCC) simulations. Increasing the magnetic field from 0 to 200 G is found to result in a drastic enhancement of the electron and the O2+ ion density due to the enhanced confinement of electrons by the magnetic field. The time and space averaged O− ion density, however, is found to remain almost constant, since both the dissociative electron attachment (production channel of O−) and the associative electron detachment rate due to the collisions of negative ions with oxygen metastables (main loss channel of O−) are enhanced simultaneously. This is understood based on a detailed analysis of the spatio-temporal electron dynamics. The nearly constant O− density in conjunction with the increased electron density causes a significant reduction of the electronegativity and a pronounced change of the electron power absorption dynamics as a function of the externally applied magnetic field. While at low magnetic fields the discharge is operated in the electronegative drift-ambipolar mode, a transition to the electropositive α-mode is induced by increasing the magnetic field. Meanwhile, a strong electric field reversal is generated near each electrode during the local sheath collapse at high magnetic fields, which locally enhances the electron power absorption. A model of the electric field generation reveals that the reversed electric field is caused by the reduction of the electron flux to the electrodes due to their trapping by the magnetic field. The consequent changes of the plasma properties are expected to affect the applications of such discharges in etching, deposition and other semiconductor processing technologies.
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影响因子：
4
作者：
A. Greb;K. Niemi;D. O’Connell;T. Gans
通讯作者：
A. Greb;K. Niemi;D. O’Connell;T. Gans
DOI：
--
发表时间：
2003-09
期刊：
--
影响因子：
--
作者：
M. Lieberman;A. Lichtenberg
通讯作者：
M. Lieberman;A. Lichtenberg
影响因子：
4
作者：
S. You;C. Chung;K. Bai;Hong-young Chang
通讯作者：
S. You;C. Chung;K. Bai;Hong-young Chang
影响因子：
3.8
作者：
Derzsi, A.;Korolov, I.;Schulze, J.
通讯作者：
Schulze, J.
DOI：
10.1103/physreva.41.4447
发表时间：
1990-04
期刊：
Physical review. A, Atomic, molecular, and optical physics
影响因子：
--
作者：
Belenguer;Boeuf
通讯作者：
Belenguer;Boeuf