Ramos Mauricio R, Crnjac Andreo, Cosic Donny, Jakšić Milko
Laboratory for Ion Beam Interactions, Ruđer Bošković Institute, Bijenicka Cesta 54, 10000 Zagreb, Croatia.
Materials (Basel). 2022 Jan 5;15(1):388. doi: 10.3390/ma15010388.
Synthetic single crystal diamond grown using the chemical vapor deposition technique constitutes an extraordinary candidate material for monitoring radiation in extreme environments. However, under certain conditions, a progressive creation of space charge regions within the crystal can lead to the deterioration of charge collection efficiency. This phenomenon is called polarization and represents one of the major drawbacks associated with using this type of device. In this study, we explore different techniques to mitigate the degradation of signal due to polarization. For this purpose, two different diamond detectors are characterized by the ion beam-induced charge technique using a nuclear microprobe, which utilizes MeV energy ions of different penetration depths to probe charge transport in the detectors. The effect of polarization is analyzed by turning off the bias applied to the detector during continuous or discontinuous irradiation, and also by alternating bias polarity. In addition, the beneficial influence of temperature for reducing the effect of polarization is also observed. Finally, the effect of illuminating the detector with light is also measured. Our experimental results indicate that heating a detector or turning off the bias, and then applying it during continuous irradiation can be used as satisfactory methods for recovering the CCE value close to that of a prepolarized state. In damaged regions, illumination with white light can be used as a standard method to suppress the strength of polarization induced by holes.
采用化学气相沉积技术生长的合成单晶金刚石是极端环境下监测辐射的一种特殊候选材料。然而，在某些条件下，晶体内空间电荷区的逐渐形成会导致电荷收集效率下降。这种现象称为极化，是使用这类器件的主要缺点之一。在本研究中，我们探索了不同的技术来减轻极化导致的信号退化。为此，使用核微探针的离子束诱导电荷技术对两种不同的金刚石探测器进行了表征，该技术利用不同穿透深度的兆电子伏能量离子来探测探测器中的电荷传输。通过在连续或不连续辐照期间关闭施加到探测器的偏压，以及交替改变偏压极性来分析极化的影响。此外，还观察到温度对降低极化效应的有益影响。最后，还测量了用光照射探测器的效果。我们的实验结果表明，加热探测器或关闭偏压，然后在连续辐照期间施加偏压，可以用作使电荷收集效率值恢复到接近预极化状态的令人满意的方法。在受损区域，用白光照射可以用作抑制空穴诱导极化强度的标准方法。
