Energy‐Sensitive GaSb/AlAsSb Separate Absorption and Multiplication Avalanche Photodiodes for X‐Ray and Gamma‐Ray Detection
Energy‐Sensitive GaSb/AlAsSb Separate Absorption and Multiplication Avalanche Photodiodes for X‐Ray and Gamma‐Ray Detection
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DOI：
10.1002/adom.201900107
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发表时间：
2019-03
影响因子：
9
通讯作者：
B. Juang;Andrew Chen;D. Ren;B. Liang;D. Prout;A. Chatziioannou;D. Huffaker
中科院分区：
文献类型：
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作者：
B. Juang;Andrew Chen;D. Ren;B. Liang;D. Prout;A. Chatziioannou;D. Huffaker
展示了用于X射线和伽马射线探测的锑基（Sb-基）分离吸收和倍增雪崩光电二极管（SAM-APD），其由GaSb吸收体和大带隙AlAsSb倍增区组成，以提高阻止高能光子的概率，同时大幅抑制少数载流子扩散。在暴露于241 Am放射源的情况下观察到明确的X射线和伽马射线泄漏，证明了理想的能量敏感探测器性能。光谱表征表明，由于吸收体中的高峰值电场降低和表面上的非辐射复合被抑制，测量的能量分辨率显著提高。此外，GaSb/AlAsSb SAM‐ APD的能量响应线性度高达59.5 keV，最小半高全宽为1.283 keV。光谱测量的进一步分析表明，器件的性能本质上是由读出电子的噪声，而不是从光电二极管的限制。这项研究提供了对Sb基能量敏感SAM‐ APD的初步了解，并为实现X射线和伽马射线光谱学的高能光子的有效检测铺平了道路。
Demonstrated are antimony‐based (Sb‐based) separate absorption and multiplication avalanche photodiodes (SAM‐APDs) for X‐ray and gamma‐ray detection, which are composed of GaSb absorbers and large bandgap AlAsSb multiplication regions in order to enhance the probability of stopping high‐energy photons while drastically suppressing the minority carrier diffusion. Well‐defined X‐ray and gamma‐ray photopeaks are observed under exposure to 241Am radioactive sources, demonstrating the desirable energy‐sensitive detector performance. Spectroscopic characterizations show a significant improvement of measured energy resolution due to reduced high‐peak electric field in the absorbers and suppressed nonradiative recombination on surfaces. Additionally, the GaSb/AlAsSb SAM‐APDs clearly exhibit energy response linearity up to 59.5 keV with a minimum full‐width half‐maximum of 1.283 keV. A further analysis of the spectroscopic measurement suggests that the device performance is intrinsically limited by the noise from the readout electronics rather than that from the photodiodes. This study provides a first understanding of Sb‐based energy‐sensitive SAM‐APDs and paves the way to achieving efficient detection of high‐energy photons for X‐ray and gamma‐ray spectroscopy.