The effect of illumination with intense light on the conduction current of metal/n-silicon diodes

Abstract

The effect of illumination with intense white light is investigated for metal/silicon diodes, such as Au, Al, and Sn/Si junctions with the native oxide layer. Light induced general degradation in the dark (I–V) curves, the larger the amplitude of the photogenerated hole current ( I L ), the larger is the degradation in Φ B , and subsequently the larger the departure of the ideality factor ( n) from unity. An exponential relationship between the photogenerated change ( Q ph ) and n is found. The capacitance of the junctions shows interesting dependence on the illumination time. A two-stage photoquenching transient behavior is observed for all the investigated junctions. This effect is bias dependent, and it operates in the three junctions at different biases. The two-stage photoquenching transient phenomenon is found to be dependent on the potential barrier height (Φ B).