We have fabricated devices with the structure InP/In0.53Ga0.47As/InP, with a InGaAs doping range varying from 2×1014 to 2×1019 cm-3. These isotype double heterostructures were doped both n and p type and were used to measure the minority-carrier lifetime of InGaAs over this doping range. At the low doping end of the series, recombination is dominated by the Shockley–Read–Hall effect. At the intermediate doping levels, radiative recombination is dominant. At the highest doping levels, Auger recombination dominates as the lifetime varies with the inverse square of the doping concentration. From fitting these data, the radiative- and Auger-recombination coefficients are deduced. © 1998 American Institute of Physics.