The mean time to failure (MTTF) for InGaAs planar photodiodes has been predicted to be 1014 hours at room temperature based on lifetests at elevated temperatures of 200, 230 and 250°C (and -12V reverse bias). This improved value is thought to be due to reductions in leakage current which lead to higher reliability. Significant reduction in background doping of the InGaAs absorption layer and mild doping (~2 x 1016cm-3) of the InP cap layer have led to lower leakage currents. The typical room temperature leakage current of a 300 um diameter photodiode is 300 pA @ -5V and a 25% increase in this value constitutes a failure. For InGaAs photodiode arrays, an additional criterion of failure, "popcorn noise" is introduced. Popcorn noise exhibits random charge (current) fluctuations in a p-n junction. The predicted MTTF for a 256-eLement In0.53Ga0.47As array is 108 hours for one diode failure and 3 x 109 hours for five diode failures. Undegraded operation has been observed with a group of In0.8Ga0 2As detectors (which absorb light out to 2.6 um) after 8000 hrs. @ 125oC.