Modeling of Sb-Heterostructure Backward Diode for Millimeter- and Submillimeter-Wave Detection

Other conference contribution, 2012

Millimeter wave and submillimeter wave detection and imaging have attracted considerable interest due to its potential in applications such as security, defense, and medical diagnosis. For such sensing and imaging systems, highly sensitive and compact solid-state detectors are the key components. Among the various existing device technologies, the antimonide based heterojunction backward tunneling diodes (HBDs) has been demonstrated as one of the most sensitive millimeter wave direct detectors. These diodes exhibit especially high curvature in the current-voltage characteristic that produces the rectification without bias. Operation without bias is a highly disable feature as the device does not suffer from large 1/f noise, a major shortcoming in other devices such as Schottky barrier diodes or resistive room temperature bolometers. HBDs with matched sensitivity as high as 50 kV/W and noise equivalent power below 0.2 pW/Hz1/2 have been demonstrated at 94 GHz, exceeding the theoretical prediction of Schottky diodes. Though Sb-HBDs were predicted very promising for submillimeter wave applications as well, little effort has been made and few have reported on its operation above 100 GHz. To improve both the performance and the operation frequency, device modeling of HBDs is strongly needed for guidance of future detector heterostructure design.