Low-noise mm-wave integrated InGaAs-based mixers

Integrated InP-based mixers can benefit millimeter and submillimeter-wave receivers by their potential for low LO power requirements (P/sub LO/) and low noise performance. An InGaAs Schottky diode´s low barrier (/spl phi//sub b//spl sim/0.25 eV) reduces the P/sub LO/ requirement but special fabrication techniques, covered here, are required to ensure Schottky quality. A quasi-optical, InGaAs integrated antenna-mixer was demonstrated at 90 GHz and obtained intrinsic noise and conversion loss performance on par with state-of-the-art planar GaAs mixer diodes. Furthermore, results indicate very low contributions of hot electron and other noise beyond shot and thermal noise. Since submillimeter mixer performance is often dominated by hot electron noise, these mixers should have potential for low-noise operation at and beyond millimeter and submillimeter frequencies.