Self-consistent multidimensional electron kinetic model for inductively coupled plasma sources.

摘要

Inductively coupled plasma (ICP) sources have received increasing interest in microelectronics fabrication and lighting industry. In 2-D configuration space (r, z) and 2-D velocity domain (;The kinetic analysis shows that the RF energy in an ICP source is extracted by a collisionless dissipation mechanism, if the electron thermovelocity is close to the RF phase velocities. A criterion for collisionless damping is thus given based on the analytic solutions. To achieve uniformly distributed plasma for plasma processing, we propose a novel discharge structure with both planar and vertical coil excitations. The theoretical results demonstrate improved uniformity for the excited azimuthal E-field in the chamber.;Non-monotonic spatial decay in electric field and space current distributions was recently observed in weakly-collisional plasmas. The anomalous skin effect is found to be responsible for this phenomenon. The proposed model successfully models the non-monotonic spatial decay effect and achieves good agreements with the measurements for different applied RF powers.;The proposed analytical model is compared with other theoretical models and different experimental measurements. The developed model is also applied to two kinds of ICP discharges used for electrodeless light sources. One structure uses a vertical internal coil antenna to excite plasmas and another has a metal shield to prevent the electromagnetic radiation. The theoretical results delivered by the proposed model agree quite well with the experimental measurements in many aspects. Therefore, the proposed self-consistent model provides an efficient and reliable means for designing ICP sources in various applications such as VLSI fabrication and electrodeless light sources.