Patent ID: 6909160

Claim:
A semiconductor light-receiving module comprising: a semiconductor light-receiving element; and an incident light direction device; wherein the semiconductor light-receiving element comprises: a substrate; a lower semiconductor layer formed on the substrate, and having a function as an optical waveguide; a light absorbing layer formed on the lower semiconductor layer, and having a refractive index higher than a refractive index of the lower semiconductor layer; an upper cladding layer formed on the light absorbing layer, and having a refractive index lower than the refractive index of the lower semiconductor layer; a light incident facet including at least one facet of the substrate, the lower semiconductor layer and the light absorbing layer; and electrodes which output current generated by absorption of light entering from the light incident facet in the light absorbing layer, by way of the upper cladding layer and the lower semiconductor layer; and wherein the incident light direction device positions the semiconductor light-receiving element such that the light is irradiated onto the light incident facet at a predetermined angle with respect to the light incident facet, such that a part of the light entering the light absorbing layer propagates in a direction parallel to a bottom face of the upper cladding layer in at least one of the light absorbing layer and the lower semiconductor layer, while another part of the light entering the light absorbing layer is reflected at the bottom face of the upper cladding layer and propagates in an oblique direction in the light absorbing layer and the lower semiconductor layer.