Applied Physics Letters · 2005 · 33 citations · 1 references
EngineeringElectrical EngineeringMaterials ScienceMicroelectronicsSemiconductor DevicesSemiconductor MaterialsHigh-frequency Semiconductor DevicesMicrowave Semiconductor DevicesNoise In Electronic DevicesNoise In Semiconductor DevicesSemiconductor DetectorsWide-bandgap Semiconductor DevicesDifferential ResistanceHeterojunctionsMicrowave DevicesNoise Equivalent PowerSchottky Barrier DiodesSchottky BarriersSchottky ContactsSemiconductor Heterojunctions
In contrast to traditional metal-semiconductor (i.e., Schottky) junctions, ErAs:InAlGaAs heterojunctions have recently been shown to provide highly “engineerable” electrical rectification characteristics through the tuning of the Schottky barrier height and differential resistance, while maintaining the very low specific capacitance for which Schottky diodes are famous. We demonstrate that these new rectifiers can operate effectively at zero bias and can be extremely sensitive at microwave frequencies. We report a tangential sensitivity of −63dBm at 3.1 GHz in an 8.0 KHz bandwidth, corresponding to a noise-equivalent power (NEP) of 8.9×10−13W∕Hz1∕2. We attribute this noise performance to the high rf-to-dc current responsivity (∼8A∕W), zero bias operation, and noise source reduction. The new diodes are found to be ∼19dB more sensitive than the best available Hewlett–Packard zero-bias diodes at comparable frequencies.
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