电应力对GaAlAs红外发光二极管低频噪声的影响

在宽范围偏置条件下，测量了电应力前后GaAlAs红外发光二极管（IRED）的低频噪声，发现应力前后1／f噪声随偏置电流变化的规律没有改变，但应力后1／f噪声幅值比应力前增加大约i00倍。基于载流子数和迁移率涨落的理论分析表明，GaAlAs IRED的1／f噪声在小电流时反映体陷阱特征，大电流时反映激活区陷阱特征，1／f噪声的增加归因于电应力在器件有源区诱生的界面陷阱和表面陷阱，因而，1／f噪声可以用来探测电应力对该类器件有源区的潜在损伤。

Effect of Electrical Stress on Low Frequency Noise in GaAlAs Infrared Ray Emitting Diodes

1/f noise in GaAlAs infrared ray emitting diodes (IREDs) is experimentally studied over a wide range of bias currents with special emphasis on the influence of electrical stress. Experimental results demonstrate similar relationships of the magnitude of 1/f noise with bias current, but after the device has been stressed, the magnitude of 1/f noise increases about 2 scalars. Based on the fluctuation mechanisms of carrier density and velocity,a model for 1/f noise in GaAlAs IREDs is developed. At small current, 1/f noise reveals characteristics of defects in the bulk region of devices (bulk defects), while at large current, it reveals defects in the active region of devices (actives defects). The increase magnitude of 1/f noise is due to some new interface traps and surface traps in active region, which are induced by electrical stress. So 1/f noise can be used to probe latent damages induced by electrical stress in active region of GaAlAs IREDs.