质子辐照对场板AlGaN／GaN HEMT器件电特性的影响

分别采用3MeV和10MeV的质子对GaN基HEMT（High Electron Mobility Transistor）器件进行辐照。实验发现：低注量辐照引起了体材料载流子浓度增加，高注量辐照引起了HEMT器件漏电流下降，跨导减小，阈值电压显著退化的结果。通过分析发现辐射感生受主缺陷引起的2DEG浓度降低是上述器件退化的主要原因。此外基于实验结果，采用辐射感生受主缺陷退化模型仿真并计算了HEMT器件主要参数随受主浓度的退化规律，仿真结果与实验结果有较好的一致性。本文实验结果也表明场板结构和SiN钝化层有效地阻止了电子陷落在表面态中，屏蔽了绝大部分的辐照损伤，是很有效的辐射加固手段。

The Effect of Proton Irradiation on the EIectricaI Properties of FP-AIGaN/GaN High EIectron MobiIity Transistors

The radiation effect of FP-GaN HEMT was investigated by using proton radiation source.After low irradia-tion fluence,the phenomena of an increase in carrier density of GaN material was found.The device showed negligible deg-radation at low proton fluences.At high fluences,the decreased drain current and transconductance as well as the obviously shifted threshold voltage of HEMT were observed.And the ohmic contact was so relative robustness to proton,but the Schot-tky characteristics degraded obviously.Utilizing the depletion approximation theory and the introduction of acceptor defects to express radiation induced defects in AlGaN/GaN heterostructures,we developed irradiation induced acceptor defects dam-age model for AlGaN/GaN HEMT.The simulations indicated that the acceptor defects induced in both channel and buffer layer dominate the radiation damage in AlGaN/GaN HEMT.A good agreement between calculations and experiments pres-ents the validity of this model.The annealing results proved that the damage induced by proton may be partially recovered. SiN-passivated FP-AlGaN/GaN HEMTs appear to be attractive candidates for space and terrestrial applications,and the HEMTs are resistant to displacement damage.