Patent ID: 8633496

Claim:
An optical device comprising: a base wafer containing silicon; a plurality of seed crystals disposed on the base wafer; and a plurality of Group 3-5 compound semiconductors lattice-matching or pseudo lattice-matching the plurality of seed crystals, wherein at least one of the Group 3-5 compound semiconductors has a photoelectric semiconductor formed therein, the photoelectric semiconductor including a light emitting semiconductor that emits light in response to a driving current supplied thereto or a light receiving semiconductor that generates a photocurrent in response to light applied thereto, at least one of the plurality of Group 3-5 compound semiconductors other than the Group 3-5 compound semiconductor having the photoelectric semiconductor has a heterojunction transistor formed therein, the plurality of seed crystals are C x1 Si y1 Ge z1 Sn 1-x1-y1-z1 (0≦x1<1, 0≦y1≦1, 0≦z1≦1, and 0<x1+y1+z1≦1), and the light emitting semiconductor and the light receiving semiconductor are Group 3-5 compound semiconductors.