Ding Man
The College of Energy and Electrical Engineering, Hohai University, Nanjing 211100, China.
Micromachines (Basel). 2021 Jun 4;12(6):661. doi: 10.3390/mi12060661.
The radiation response of AlO on silicon substrate under gamma-rays is studied in this article. The atomic layer deposited AlO based metal-oxide-semiconductor structures were irradiated under gamma-ray with the total dose of 1.2 Mrad(Si)/2.5 Mrad(Si)/4 Mrad(Si). The generation, transportation and trapping characteristics of radiation induced charges were studied by using electronic, physical and chemical methods. Firstly, the radiation induced trapped charge density in AlO is up to 10 cm, with the effective trapping efficiency of 7-20% under irradiation. Secondly, the leakage current through AlO changes little with the increase of radiation total dose. Thirdly, oxygen vacancy in AlO and O dangling bonds and Al-Si metallic bonds at AlO/Si interface are dominant radiation induced defects in AlO/Si system, and the valence band offset between AlO and Si is found to decrease after irradiation. From the results we can see that AlO is radiation resistant from the aspect of leakage current and crystallization characteristics, but the radiation induced charge trapping and new defects in AlO/Si structure cannot be ignored. This paper provides a reference for the space application of AlO based MOS devices.
本文研究了硅衬底上AlO在伽马射线作用下的辐射响应。采用原子层沉积法制备的基于AlO的金属氧化物半导体结构，在总剂量为1.2 Mrad(Si)/2.5 Mrad(Si)/4 Mrad(Si)的伽马射线照射下进行辐照。利用电子、物理和化学方法研究了辐射诱导电荷的产生、输运和俘获特性。首先，AlO中辐射诱导的俘获电荷密度高达10 cm，辐照下有效俘获效率为7 - 20%。其次，通过AlO的漏电流随辐射总剂量的增加变化不大。第三，AlO中的氧空位、AlO/Si界面处的O悬键和Al - Si金属键是AlO/Si系统中主要的辐射诱导缺陷，且辐照后AlO与Si之间的价带偏移减小。从结果可以看出，从漏电流和结晶特性方面来看，AlO具有抗辐射能力，但AlO/Si结构中辐射诱导的电荷俘获和新缺陷不容忽视。本文为基于AlO的MOS器件的空间应用提供了参考。
