Abstract

There has been considerable interest in InGaAs photodiodes which respond in the long-wavelength range (1.0-1.6 μm) because of low dark-current characteristics.^1,2 Recently, Kim et al. reduced the dark current of the photodiode by using a wide-band gap InGaAsP layer to decrease the surface leakage current.³ Campbell et al.⁴ have shown that the dark current can be reduced to values as low as 50 pA by using a semi-insulating InP cap layer. We present a new InGaAs/InP PIN photodiode with a covered-mesa (CM) structure. Dark currents as low as 20 pA have been achieved with this structure.

© 1987 Optical Society of America