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采用归一化能量1 Me V的中子脉冲反应堆对Al Ga N/Ga N异质结材料进行了辐照研究。实验发现,经1015cm-2注量的中子辐照后,异质结材料的二维电子气(2DEG)载流子浓度(ns)下降,而2DEG迁移率由于受到ns的调制作用略有增加,同时辐照导致的载流子浓度ns下降造成了沟道串联电阻的增加和异质结构阈值电压(VTH)的正向漂移。分析认为,辐照感生类受主缺陷是造成ns下降和阈值电压漂移的原因。原子力显微镜(AFM)和X射线衍射仪(XRD)的测试结果表明,辐照后材料的表面形貌有所恶化,材料应变基本不变,而材料的螺位错和刃位错密度辐照后都略有增加。此外,实验结果还表明初始材料质量越好,辐照退化越小。
AlGaN / GaN heterostructures were irradiated by neutron pulsed reactors with normalized energy of 1 MeV. It was found that the 2DEG carrier concentration (ns) of the heterojunction material decreased after irradiation with 1015cm-2 neutron, while the 2DEG mobility slightly increased due to the modulation effect of ns , While the decrease of the carrier concentration ns due to irradiation leads to an increase of the series resistance of the channel and the forward drift of the heterostructure threshold voltage (VTH). The analysis shows that the main defect of irradiation-induced species is the reason of the decrease of ns and the shift of threshold voltage. The results of atomic force microscopy (AFM) and X-ray diffraction (XRD) show that the surface morphology of the irradiated materials is deteriorated and the strain of the materials is almost unchanged. However, the screw dislocation and the dislocation density of the materials are irradiated Slightly increased. In addition, the experimental results also show that the better the quality of the initial material, the smaller the radiation degradation.