Background carrier concentration in midwave and longwave InAs/GaSb type II superlattices on GaAs substrate

We report on the measurement of the background carrier concentration of midwave and long-wave infrared (MWIR and LWIR) type-II InAs/GaSb superlattices (SLs) on GaAs substrates. The transport properties of SLs are characterized using temperature dependent Hall measurements. It is found that the conduction in the MWIR SLs is dominated by holes at low temperatures and by electrons at high temperatures. However, the transport in LWIR SL is dominated by electrons at all temperatures. In-plane transport characteristics of LW SLs grown at different temperatures shows that interface roughness scattering is the dominant scattering mechanism at high temperatures.