对光电耦合器件1/f噪声和g-r噪声(产生-复合噪声)的偏置特性及其产生机理进行了实验和理论研究.结果表明:在低频段,光电耦合器件的g-r噪声通常表现为叠加1/f噪声,且两者均随输入电流的增加呈现先增大后减小的规律.通过测量前级噪声和后级噪声,发现光电耦合器件的g-r噪声源为后级光敏三极管.理论分析表明:光电耦合器件的1/f噪声主要为表面1/f噪声,g-r噪声则源于光敏三极管发射结空间电荷区的深能级对载流子的俘获和发射.

Experimental dependences on bias current and physical mechanisms of 1/f noise and g-r noise (generation-recombination noise) in Optoelectronic Coupled Devices (OCDs) are studied. Experimental results demonstrate that g-r noise of OCDs emerges with 1/f noise in the range of low frequencies and both of them have a similar rule, that is to say, in the beginning, magnitudes of g-r noise and 1/f noise increase and then decrease with the bias current keep increasing. From measuring noise of the front part and back part in OCDs, it is found that g-r noise source in OCDs lies in the photosensitive transistor. Based on mechanisms of carrier fluctuation, it is discussed that 1/f noise in OCDs belongs to surface 1/f noise and g-r noise is due to trapping and detrapping processes between carriers and deep-level in the emitter space-charge region of photosensitive transistor.