在 InP 衬底上的 InGaAs/AlInAs 超晶格雪崩光电二极管中实现碰撞电离特性的工程设计。

Engineering of impact ionization characteristics in InGaAs/AlInAs superlattice avalanche photodiodes on InP substrate.

机构信息

Department of Electrical and Computer Engineering, The Ohio State University, Columbus, OH, 43210, USA.

Department of Physics, University of Illinois, Chicago, IL, 60607, USA.

出版信息

Sci Rep. 2020 Oct 7;10(1):16735. doi: 10.1038/s41598-020-73810-w.

DOI:10.1038/s41598-020-73810-w

PMID:33028858

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7542422/

Abstract

We report on engineering impact ionization characteristics of InGaAs/AlInAs superlattice avalanche photodiodes (InGaAs/AlInAs SL APDs) on InP substrate to design and demonstrate an APD with low k-value. We design InGaAs/AlInAs SL APDs with three different SL periods (4 ML, 6 ML, and 8 ML) to achieve the same composition as AlGaInAs quaternary random alloy (RA). The simulated results of an RA and the three SLs predict that the SLs have lower k-values than the RA because the electrons can readily reach their threshold energy for impact ionization while the holes experience the multiple valence minibands scattering. The shorter period of SL shows the lower k-value. To support the theoretical prediction, the designed 6 ML and 8 ML SLs are experimentally demonstrated. The 8 ML SL shows k-value of 0.22, which is lower than the k-value of the RA. The 6 ML SL exhibits even lower k-value than the 8 ML SL, indicating that the shorter period of the SL, the lower k-value as predicted. This work is a theoretical modeling and experimental demonstration of engineering avalanche characteristics in InGaAs/AlInAs SLs and would assist one to design the SLs with improved performance for various SWIR APD application.

摘要

我们报告了在 InP 衬底上的 InGaAs/AlInAs 超晶格雪崩光电二极管（InGaAs/AlInAs SL APD）的工程影响电离特性，以设计和展示具有低 k 值的 APD。我们设计了具有三种不同 SL 周期（4 ML、6 ML 和 8 ML）的 InGaAs/AlInAs SL APD，以实现与 AlGaInAs 四元随机合金（RA）相同的组成。RA 和三个 SL 的模拟结果预测，SL 的 k 值低于 RA，因为电子可以轻易达到其影响电离的阈值能量，而空穴则经历多次价带微带散射。较短的 SL 周期显示出较低的 k 值。为了支持理论预测，设计的 6 ML 和 8 ML SL 进行了实验验证。8 ML SL 的 k 值为 0.22，低于 RA 的 k 值。6 ML SL 表现出比 8 ML SL 更低的 k 值，这表明如预测的那样，SL 的较短周期导致更低的 k 值。这项工作是对 InGaAs/AlInAs SL 中雪崩特性的理论建模和实验演示，将有助于设计具有改进性能的 SL，以满足各种 SWIR APD 应用的需求。