Surface passivation in detectors is designed to improve the performance and stabilize the characteristics over time and ambient. In Cd${}_{\mathrm{1-x}}$Zn${}_{\mathrm{x}}$Te radiation detectors, oxidation by plasma is a well-known passivation method, but its physics is not fully understood. This study focuses on the macroscopic and microscopic effects of plasma treatment. It is shown that plasma oxidation before contact deposition causes a considerable decrease in the device’s dark current and that this reduction is in a strong correlation with the lowering of the surface potential. X-ray photoelectron spectroscopy (XPS) measurements revealed a significant increase in TeO ₂ fraction on the plasma-treated surface. The main conclusion of this study is that the plasma-related effects are not confined to the surface layer. Furthermore, the deep penetration of plasma treatment byproduct takes place over long time periods, which may lead to variations in device characteristics. The effects were corroborated by several characterization techniques. DC current–voltage measurements combined with layer-by-layer stripping indicate plasma signature deep into the bulk. Transient current technique (TCT) results demonstrate that the plasma treatment affects the electric field distribution millimeters into the bulk. Photo-induced current transient spectroscopy (PICTS) and thermoelectric emission spectroscopy (TEES) measurements reveal plasma-related traps in-depth of the CdZnTe crystals.

检测器中的表面钝化旨在改善性能并在一段时间和环境中稳定特性。镉${}_{\mathrm{1-x}}$锌${}_{\mathrm{X}}$在辐射探测器中，等离子体氧化是一种众所周知的钝化方法，但是其物理原理尚未完全被理解。这项研究的重点是等离子体处理的宏观和微观效果。结果表明，接触沉积之前的等离子体氧化会导致器件的暗电流显着降低，并且这种降低与表面电势的降低密切相关。X射线光电子能谱（XPS）测量显示TeO ₂显着增加等离子体处理过的表面上的分数。这项研究的主要结论是，与等离子体相关的作用并不局限于表面层。此外，等离子体处理副产物的深层渗透需要很长时间，这可能导致器件特性发生变化。几种表征技术证实了这种效果。直流电流-电压测量与逐层剥离相结合，表明等离子信号深入主体。瞬态电流技术（TCT）的结果表明，等离子体处理会影响以毫米为单位的电场分布。光感应电流瞬态光谱法（PICTS）和热电发射光谱法（TEES）的测量揭示了CdZnTe晶体中与等离子体有关的陷阱的深度。