Improved performance of implanted n+-p Hg1-xCdxTe photodiodes using insulated field plates

Using insulated field plates, we have demonstrated that surface leakage had been limiting the RoA of our ion-implanted n+ -on-p (Hg, Cd) Te photodiodes. This leakage is believed to be tunneling current across a pinched-off depletion region at the surface. We have used gated diodes to eliminate leakage and improve RoA to the diffusion limit at 77°K for Hg0.8Cd0.2Te photodiodes.