为了研究一种无荧光粉的单芯片白光发光二极管(LED)的光电性质,实际测量了它的升温电致发光光谱和升温电流-电压(I-V)特性,并测量了相似结构的蓝光LED以作对比。实验发现白光LED的电致发光光谱中有一个与有源区中的深能级相关的较宽的长波长发光峰,根据这个发光峰的强度与温度之间的依赖关系,通过数据拟合,得到了深能级的平均激活能,约为199 meV。由于有源区中存在大量深能级,也对白光LED的I-V特性产生一定影响,有源区中的深能级成为额外的载流子源,使白光LED的I-V特性表现出独特的性质。
In order to investigate the optical and electrical characteristics of one kind of phosphor-free white light-emitting diode(LED),the electroluminescence and I-V characteristics with increasing temperature of the white LED were measured,and a blue LED with the similar structure was measured for comparison.A wide long wavelength emission peak related to the deep-level states in the active region was observed in the white LED.According to the simulation of the emission intensity dependency of this peak with temperature,the average activation energy of deep-level states was obtained,which is about 199 meV.Deep-level states in the active region also influenced the I-V characteristics of the white LED.Deep-level states in the active region became extra source of carriers and contribute to the unique I-V characteristics of the white LED.