In0.83Ga0.17As/InP PIN-photodiode heterostructures with different doping levels have been grown by molecular beam epitaxy. Metamorphic buffer layers were applied to prevent misfit dislocations nucleation in active layers.  Capacitance-voltage and current-voltage curves of fabricated photodiodes have been measured and analysed. The impact of various dark current mechanisms has been estimated after the measurements of current-voltage curves  at different temperatures.