Patent ID: 7150569

Claim:
An optical device mounted substrate assembly comprising: a ceramic substrate having a front surface and a first recess having an open end at least at the front surface; an optical device mounted on the front surface of the ceramic substrate and having at least one of a light emitting portion and a light receiving portion, the optical device capable of being optically connected to one of an optical waveguide and an optical fiber connector in a way as to align optical axes of the optical device and one of the optical waveguide and the optical fiber connector with each other; a resin layer disposed in the first recess and having a second recess smaller in diameter than the first recess and having an open end at least at a side corresponding to the front surface; and an alignment guide member press-fitted in the second recess and having a protruded portion protruding from the front surface of the ceramic substrate and fittingly engageable in an alignment hole of one of the optical waveguide and the optical fiber connector, wherein the second recess is a high-precision machined hole, and the alignment guide member includes a guide pin fitted in the high-precision machined hole; and wherein the resin layer contains an inorganic filler having a thermal conductivity higher than that of a resin material forming the resin layer.