GaN基多量子阱蓝光LED的γ辐照效应

Gamma radiation effect on GaN-based blue light-emitting diodes with multi-quantum well

本文用4×104Ci(1Ci=3.7×1010Bq)的60Co源(剂量率2×105rad(Si)/h)对GaN基InGaN/GaN多量子阱蓝光LED进行5种剂量的γ射线的辐照实验.通过辐照前后蓝光LED的波长、色纯度、最大半峰宽(FWHM)和电流-电压(I-V)、电流-光通量(I-F)等电光学特性分析,得到γ射线对GaN基LED器件的辐照效应.结果发现,辐照后LED器件的发光一致性和均匀性变差,在20mA工作电流下,最大剂量下器件发光强度衰减近90%,光通量衰减约40%,并得到器件的抗辐照能力的参数τ0Kγ为4.039×10-7rad.s-1,发现较低的正向偏压下(小于2.6V)器件的饱和电流随辐照总剂量增大而增大.

We study the irradiation effects of the GaN-based blue light-emitting diodes（LEDs） with InGaN/GaN multi-quantum well irradiated by five doses of ^60Co （4×10^4 Ci） at room temperature. From the analyses of the characteristics of the current-voltage （I-V） relation, current-luminous flux （F-L） relation, chromatic purity, luminous intensity, luminous flux, the full width at half maximum, and the wavelength of LEDs samples before and after irradiation, we obtain the effects of γ irradiation on the devices. It shows that the consistency and uniformity of the samples become worse after irradiation. At the 20 mA working current, the luminous intensity reduces by 90% and the luminous flux falls by 40% at the maximum total dose. The quantity τ0Kγ describing the radiation hardness of the LEDs is equal to 4.039×10^-7 rad·s^-1, and the saturation current increases at lower positive bias （〈2.6 V） with the increasing total dose.