论文标题
退火对稀薄增益雪崩探测器的运行影响
Annealing effects on operation of thin Low Gain Avalanche Detectors
论文作者
论文摘要
来自Hamamatsu光子学的几个稀薄的低增益雪崩检测器被中子辐照到最高$φ_{eq} = 3 \ cdot10^{15} $ cm $^{ - 2} $的不同等效通量。辐照后，他们以60 $^\ circ $ c的步骤将其退火至$> 20000 $分钟。它们的性质，主要是完全耗尽电压，增益层耗尽电压，产生和泄漏电流以及它们在收集的电荷和时间分辨率方面的性能，在这些步骤之间确定。 发现退火对定时分辨率和收集电荷的影响不是很大，主要发生在前几十分钟内。这是主动初始受体浓度降低的结果 随着时间的流逝，观察到大约10 \％的变化。对于检测器操作的任何相关退火时间，由于其厚度很小，并且需要高偏置电压操作，因此散装中有效掺杂浓度的变化会微不足道地影响了设备的性能。在很长的退火时期，大容量中有效掺杂浓度的增加导致增益层中电场的显着增加，并且通过此导致给定电压时增益的增加。泄漏电流根据发电电流退火而减小。
Several thin Low Gain Avalanche Detectors from Hamamatsu Photonics were irradiated with neutrons to different equivalent fluences up to $Φ_{eq}=3\cdot10^{15}$ cm$^{-2}$. After the irradiation they were annealed at 60$^\circ$C in steps to times $>20000$ minutes. Their properties, mainly full depletion voltage, gain layer depletion voltage, generation and leakage current, as well as their performance in terms of collected charge and time resolution, were determined between the steps. It was found that the effect of annealing on timing resolution and collected charge is not very large and mainly occurs within the first few tens of minutes. It is a consequence of active initial acceptor concentration decrease in the gain layer with time, where changes of around 10\% were observed. For any relevant annealing times for detector operation the changes of effective doping concentration in the bulk negligibly influences the performance of the device, due to their small thickness and required high bias voltage operation. At very long annealing times the increase of the effective doping concentration in the bulk leads to a significant increase of the electric field in the gain layer and, by that, to the increase of gain at given voltage. The leakage current decreases in accordance with generation current annealing.
