Dark Current Analysis of InAs/GaSb Type II Superlattice Infrared Detectors

The infrared imaging performance of type-II superlattice (T2SL) has been widely used in civil and aerospace fields. Due to the special band structure and material properties, the T2SL has the advantages of the adjustable bandgap, a wide range of spectral response (2– $30~\mu \text{m}$ ), effectively inhibiting Auger recombination, low cost, and good uniformity in large areas. InAs/GaSb T2SL is considered to be a promising material to advance the performance of photoelectric devices, especially in the long-wave range. With the development of science and technology and the continuous efforts of scientists, the T2SL has made great progress in material growth, device design, and process research. However, there is still a gap to the theoretically values. This article discusses the reasons for the performance degradation of T2SL devices, especially the surface and bulk dark current factors, and introduces various methods to reduce dark current and advantages and disadvantages of these methods.