大功率白光LED伏安特性和正向电压温度特性研究
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摘要
在Ga N基大功率白光发光二极管(LED)老化过程中,有部分器件在小电流驱动下出现亮度不一致的现象,对其伏安特性和正向电压温度特性进行了研究。实验结果发现在小电流驱动下发光微弱的LED漏电流严重增大,在高温和大电流驱动的情况下LED正向电压随温度的变化偏离了线性关系,正向电压随温度的变化系数由负数变为正数。同时,通过对比实验表明这种器件出现的反常现象会伴随着寿命和可靠性问题。
In the aging process of the GaN based high-power white light-emitting diodes(LEDs), the brightness of some LEDs is inconsistent at the low injection current, and the current-voltage characteristic and the temperature characteristic of the forward voltage of GaN based high-power white LEDs are studied. The experimental results show that the dimmest LED leakage current increases seriously at the low injection current.In the case of high temperature and high injection current, the forward voltage of LED deviates linearly with the increase of temperature, and the temperature coefficient changes from negative to positive. By comparing the result of another group LEDs with the same package epoxy, it's find that the appearance of this abnormal phenomenon of this device will be accompanied by problems of life and reliability.
In the aging process of the GaN based high-power white light-emitting diodes(LEDs), the brightness of some LEDs is inconsistent at the low injection current, and the current-voltage characteristic and the temperature characteristic of the forward voltage of GaN based high-power white LEDs are studied. The experimental results show that the dimmest LED leakage current increases seriously at the low injection current.In the case of high temperature and high injection current, the forward voltage of LED deviates linearly with the increase of temperature, and the temperature coefficient changes from negative to positive. By comparing the result of another group LEDs with the same package epoxy, it's find that the appearance of this abnormal phenomenon of this device will be accompanied by problems of life and reliability.
引文
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[4]毛清华,刘军林,全知觉,等.p型层结构与掺杂对Ga In N发光二极管正向电压温度特性的影响[J].物理学报,2015,64(10):270-275.
[5]Jiajia Fu,Lixia Zhao,Haicheng Cao,et al.Degradation and corresponding failure mechanism for Ga N-based LEDs[J].Appl.Phys.Lett.2016,6(5):055219-1-055219-10.
[6]Linwang Xu,Keyuan Qian.Aging mathematical model of In Ga N/Ga N LEDs based on non-radiative recombine-ation[J].Appl.Phys.Lett.2016,1864(1):020172-1-020172-7.
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[8]代爽,于彤军,李兴赋,等.In Ga N/Ga N多量子阱蓝光发光二极管老化过程中的光谱特性[J].光谱学与光谱分析,2014,2(34):327-330.
[9]余菲,金雷.Ga N发光二极管的老化数学模型及寿命测试方法[J].中国激光,2011,38(8):190-194.
[2]李炳乾,刘玉华,冯玉春.大功率Ga N基发光二极管等效串联电阻的功率耗散及其对发光效率的影响[J].物理学报,2008,57(1):477-480.
[3]E Fred Schubert.Light-emitting diodes[M].New York:Cambridge University Press,2006:109.
[4]毛清华,刘军林,全知觉,等.p型层结构与掺杂对Ga In N发光二极管正向电压温度特性的影响[J].物理学报,2015,64(10):270-275.
[5]Jiajia Fu,Lixia Zhao,Haicheng Cao,et al.Degradation and corresponding failure mechanism for Ga N-based LEDs[J].Appl.Phys.Lett.2016,6(5):055219-1-055219-10.
[6]Linwang Xu,Keyuan Qian.Aging mathematical model of In Ga N/Ga N LEDs based on non-radiative recombine-ation[J].Appl.Phys.Lett.2016,1864(1):020172-1-020172-7.
[7]S W Lee,D C Oh,H Goto,et al.Origin of forward leakage current in Ga N-Based light-emitting devices[J].Appl.Phys.Lett.2006,89(3):132117-1-132117-3.
[8]代爽,于彤军,李兴赋,等.In Ga N/Ga N多量子阱蓝光发光二极管老化过程中的光谱特性[J].光谱学与光谱分析,2014,2(34):327-330.
[9]余菲,金雷.Ga N发光二极管的老化数学模型及寿命测试方法[J].中国激光,2011,38(8):190-194.