Highly sensitive planar-doped GaAsSb-based backward diodes at 170 GHz

Highly sensitive p-GaAsSb/i-InAlAs/n-InGaAs backward diodes up to 170 GHz were achieved by adopting planar doping in the n-InGaAs layer. The planar doping is effective to control interband tunneling and junction capacitance (C_j) in the diodes. When doping concentration in the n-InGaAs layer was reduced to 1 × 10¹⁷ cm^-3, backward-diode characteristics were obtained when planar doping was 2 × 10¹² cm^-2. We achieved an unmatched and matched sensitivity of about 1,000 and 2,257 V/Wusing a relatively large mesa size of 2 × 2 μm² at 170 GHz.