Characteristics of double-cascade photodiodes based on p-i-n AlGaAs/GaAs diodes connected by n++-GaAs/i-GaAs/i-AlGaAs/p++-AlGaAs tunnel diodes

Abstract Characteristics of double-cascade nonmonolithic p-i-n AlGaAs/GaAs photovoltaic converters of high-power laser radiation, electrically combined with n ++ -GaAs/i-GaAs/i-AlGaAs/p ++ -AlGaAs tunnel diodes, have been studied. The AlGaAs/GaAs p-i-n structures of the photovoltaic converters and n ++ -GaAs/i-GaAs/i-AlGaAs/p ++ -AlGaAs tunnel diodes were grown by molecular-beam epitaxy. The photoelectric characteristics of the double-cascade AlGaAs/GaAs photovoltaic converters were examined in the temperature range from 103 to 298 K under excitation with a laser light wavelength of 809 nm and a power density ⩽92 W/cm 2 . The double-cascade p-i-n AlGaAs/GaAs nonmonolithic photovoltaic converters of planar design had a fill factor of 0.88 and efficiency of 58.2% at a temperature of 103 K. It was shown experimentally that the current-voltage characteristics of the connecting n ++ -GaAs/i-GaAs/i-AlGaAs/p ++ -AlGaAs tunnel diodes affect the photoelectric parameters of the double-cascade photovoltaic converters of high-power laser light.