Using high quality, single crystalline InP nanowire grown on silicon substrate, we demonstrates sensitive avalanche photodiode with 26.6 A/W and bipolar junction phototransistor with 4 A/W integrated onto silicon substrate. The avalanche photodiode has unique radial p-n junction that allows it to reach a high avalanche gain of 100 at a low bias of 1 V. The bipolar junction phototransistor integrates a sensitive photodiode with a receiver circuit, creating a compact, monolithic receiver circuit for optical interconnect application. These devices are promising in bringing low energy, high bandwidth optical interconnects to silicon electronics. © 2014 IEEE.