Scaling of High-Performance InAs/AlSb/GaSb Heterostructure Detectors for Millimeter-Wave and Submillimeter-Wave Sensing and Imaging

The state of the art in millimeter-wave detection and imaging using Sb-heterostructure detectors has been advanced recently with demonstration of excellent low-noise performance through the use of very thin (< 15 Aring) tunnel barriers. This reduction in tunnel barrier thickness improves the noise by reducing the thermal noise associated with the junction resistance, R_j. However, the thinner barrier also increases the junction capacitance, C_j, and the decreased R_j and increased C_j degrade the detector´s sensitivity, beta_v, and frequency response. In this work, the combined effects of scaling the tunnel barrier thickness and device area have been studied experimentally and modeled, allowing optimization of the device performance for both low noise and high cut-off frequency for millimeter-wave and sub-millimeter-wave sensing and imaging.