High performance epitaxial HgCdTe photodiodes for 2.7 µm applications

High performance photovoltaic devices tailored for 2.7 µm cut-off have been fabricated on liquid phase epitaxial HgCdTe/CdTe. The peak external quantum efficiency is measured to be 67% without any AR-coating. The measured zero-bias resistance-area (R0A) product is 5 ∼ 10⁴µ-cm²at 195K and µ10⁷Ω-cm²at 140K. The demonstrated performance of HgCdTe photovoltaic devices tailored for a 2.7 µm cut-off is considerably better than conventional PbS photodetectors, which have appeared in available literature and which are currently in wide use in this spectral range.