Radiation damage of InGaAs device and its decrease method

在核反应堆、高能粒子加速器和人造卫星的使用不断扩大的今天，能够在高辐射环境中正常工作的半导体器件的开发正在世界各地广泛进行。本课题研究了InGaAs器件在1 MeV电子、1 MeV快中子、20 MeV质子和20 MeV α射线辐照下，随着注量和辐射源的变化，器件电学性能的退化和晶格缺陷的产生。InGaAs器件电学性能的退化随辐照注量的增加而增大，随锗含量的增加而减小.辐照后，在InGaAs外延层中观察到电子俘获能级，这可能与Ga间隙络合物有关。电子俘获能级作为产生-复合中心，是导致器件性能下降的主要原因.在InGaAs HEMT（高电子迁移率晶体管）的Si掺杂的Ino.49Gao.51P施主层中诱导的电子捕获能级被认为是由于施主去除而导致漏电流和有效迁移率降低的主要原因。质子辐照的损伤系数几乎与中子辐照相同，比电子辐照的损伤系数大三个数量级。这种差异是由于撞击原子的数量不同，这与质量的差异和形成晶格缺陷的核碰撞的可能性有关。降低的性能和诱导的深能级通过热退火恢复。

In these days when the use of nuclear reactors, high-energy particle accelerators and artificial satellites expands, the development of semiconductor devices, which can normally operate in a radiation-rich environment, is extensively taking place everywhere. In the project, the degradation of the electrical performance and the generated lattice defects in InGaAs devices, subjected to 1-MeV electrons, 1-MeV fast neutrons, 20-MeV protons and 20-MeV alpha rays, were investigated as a function of fluence and radiation source.The main conclusions which can be made from the research project :1. The degradation of the electrical performance of InGaAs devices increases with increasing radiation fluence, while it decreases with increasing germanium content.2. After irradiation, electron capture levels are observed in InGaAs epitaxial layers which are probably related with a Ga interstitial complex. The electron capture levels, which act as generationrecombination center, are mainly responsible for the degradation of device performance.3. The electron capture levels induced in Si-doped Ino.49Gao.5lP donor layer of InGaAs HEMT (High Electron Mobility Transistor) are thought to be mainly responsible for the decrease of the drain current and effective mobility due to the donor removal/ 4. The damage coefficient for proton irradiation is nearly the same as for neutron irradiation and is about three orders of magnitude larger than that for electron irradiation. This difference is due to the' different number of knock-on atoms, which is correlated with the difference of mass and the possibility of nuclear collisions for the formation of lattice defects.5. The degraded performance and induced deep levels recover by thermal annealing.