纯绿LED的辐射机理和深能级研究  

RADIATIVE RECOMBINATION MECHANISMS AND DEEP LEVELS OF N-FREE GaP LIGHT-EMITTING DIODES

作　　者：高瑛[1] 赵家龙[1] 苏锡安[1] 刘学彦[1] 胡恺生[2] 丁祖昌[3] 毋必先 华为民 

机构地区：[1]中国科学院长春物理研究所,长春130021 [2]机电部电子材料研究所,300062 [3]浙江大学物理系,310027

出　　处：《发光学报》1992年第4期296-303,共8页Chinese Journal of Luminescence

基　　金：国家自然科学基金;中国科学院长春物理所激发态开放实验室基金

摘　　要：本文结合N-free GaP材料外延生长和器件研制,用时间分辨光谱和发射光谱对温度的依赖关系,研究了构成绿色辐射的不同跃迁过程,测量了它们的光生载流子寿命.通过阴极射线轰击芯片前后深能级瞬态谱(DLTS)的分析,并根据退化过程中近红外光谱的变化,探讨了影响纯绿LED效率的主要因素.The near-band emission mechanisms and deep levels of pure green LED has been studied from 77K to room temperature.The samples were fabricated by an overcompensation liquid phase epitaxy method.The peak wavelength of LEDs at 300K was 555nm. Experimental evidences are presented to the emission of dominating centers at 77K, originating from D-A pair transition. When decay time increases, peaks shift apparently toward low energy as a consequence of the distance dependence of the Coulomb interaction. Also, exciton transitions were observed at 77K and the free-exciton recombination did not decay -exponentially. So that it becomes the dominant emission mechanism at room temperature.The near-infrared electroluminescence spectra of N-free GaP LED are complicated. Three overlapping broad emission ; bands were observed and decomposed. Their spectra fit Gaussian line shapes and peak energies are 1080nm(1.15eV), 1260nm(0.98eV)and l510nm(0.82eV), respectively. The 1080nm and 1510nm bands are related to the presence of oxygen and 1260nm band is associated with different recombination processes, involving the PGa antisite defect.

关 键 词：发光器件 LED 绿色 辐射机制 能级 

分 类 号：TN383[电子电信—物理电子学]