Contribution of dislocations to 1/foise in mercury cadmium telluride infrared photovoltaic detectors

摘要

Contribution of dislocations to 1/f oise has been investigated by analysing the temperature dependence of the noise, dark current and zero-bias resistance-area product of mercury cadmium telluride (HgCdTe) diodes. It is shown that irrespective of the type of diode, i.e. n-on-p or p-on-n, dislocation contribution to 1/f noise can be described by i_n = 1 x 10~(-2) I_(sh) and i_n = 6 x 10~(-4) I_(sh) for planar and mesa configurations respectively, where, I_(sh) is the current conducted through the dislocations in the base of the diode. A physical model, consistent with the shunt resistance behaviour of dislocations, has been proposed to understand the role of dislocations in enhancing 1/f noise of these diodes.