Electrical performance of InAs/AlSb/GaSb superlattice photodetectors

• N-structure is a new design of barrier infrared detector based on InAs/AlSb/GaSb material system.
• AlSb unipolar barriers are designed for low dark current with high resistance and detectivity.
• Electrical performances of N-structure are superior for higher temperature applications.
• Minority carrier lifetimes are highly important for understanding of carrier transport and improving the device performance.
• Shockley Model is used to extract the minority carrier lifetimes from temperature dependence of current–voltage measurements.

Temperature dependence of dark current measurements is an efficient way to verify the quality of an infrared detector. Low dark current density values are needed for high performance detector applications. Identification of dominant current mechanisms in each operating temperature can be used to extract minority carrier lifetimes which are highly important for understanding carrier transport and improving the detector performance. InAs/AlSb/GaSb based T2SL N-structures with AlSb unipolar barriers are designed for low dark current with high resistance and detectivity. Here we present electrical and optical performance of such N-structure photodetectors.