n‐pjunction photovoltaic detectors in PbTe have been fabricated using Sb+ion implantation to create then‐type layer. At 77 °K, 15‐mil square diodes have had zero‐bias resistances as high as 15 M&OHgr; for a resistance‐area product of 2.1×104&OHgr;cm2. Peak detectivities at 4.4 &mgr;m in reduced background as high as 1.6×1012cmHz1/2/W were observed. Diode quantum efficiencies were typically 40% at 4.4 &mgr;m.