高功率脉冲磁控溅射(HiPIMS)等离子体 放电时空特性研究进展

高功率脉冲磁控溅射（HiPIMS）放电凭借着高离化率优势，已经成为物理气相沉积（PVD）领域的核心技术。鉴于HiPIMS放电具有复杂的物理场配置和兆瓦级的峰值功率，其产生的不均匀等离子体严重影响着薄膜的性能。从HiPIMS放电等离子体的时间和空间特性角度出发，结合放电靶电流、等离子体阻抗、离子饱和电流的特性，以及各种粒子在不同时刻和空间位点对应的相互作用和运动轨迹，综述了近年来国际上关于HiPIMS脉冲放电过程中等离子体参数的时空演变特性以及脉冲等离子体动力学行为，主要包含了等离子体物理量的时间演变规律，复杂物理场的空间分布行为，粒子密度、能量的扩散传输机制，靶材粒子离化程度的表征方法等，并全面地叙述了气体原子稀释效应、气体循环、双极扩散、等离子体波、旋转的spoke等不稳定传输特性。此外，依据等离子体时空特性，总结出HiPIMS放电沉积速率低的内因，介绍了提高沉积速率的方法和机理。最后，指出了目前关于HiPIMS时空特性研究方面存在的问题和发展方向。

Temporal/Spatial Characteristics of Plasma Discharge by High Power Impulse Magnetron Sputtering (HiPIMS)

High power impulse magnetron sputtering (HiPIMS) discharge has become a core technology in the field of physical vapor deposition (PVD) due to high ionization rate. In view of the complex physical field and the high peak power (~MW) in HiPIMS discharge, the uneven plasma seriously affects the performance of the thin films. From the temporal/spatial characteristics of HiPIMS discharge plasma, the temporal/spatial evolution characteristics of plasma parameters and the dynamic behavior of pulsed plasma in the process of HiPIMS pulse discharge in recent years were analyzed based on the characteristics of discharge target current, plasma impedance, ion saturation current, and the corresponding interactions and motion trajectories of various particles at different time and space sites, which mainly included the temporal evolution law of plasma physical quantity, the spatial distribution behavior of complex physical field, the diffusion and transmission mechanism of particle density and energy, and the characterization method of target particle ionization degree. The unstable transmission characteristics of gas atom dilution effect, gas circulation, bipolar diffusion, plasma wave, rotating spoke, etc. were also comprehensively described. In addition, according to the temporal/spatial characteristics of plasma, thefactors of lower deposition rate in HiPIMS were summarized, and the methods and mechanism of increasing deposition rate were introduced. Finally, the existing problems and development direction in the research on the temporal/spatial characteristics of HiPIMS are pointed out.