The fitted parameters for the analytic function used to specify doping- and temperature-dependent low-field mobilities for In_0.53Ga_0.47As is described in this paper. The developed model was compared with other mobility models as well as measured Hall data from periodical literature and very good agreement is observed. The result of this work was used to develop an In_0.53Ga_0.47As interdigitated lateral p-i-n photodiode (ILPP) model and good correlation was obtained when compared with the experimentally developed device. The results of this work would be useful in the development of In_0.53Ga_0.47As-based devices using commercial device simulation packages.