Optical semiconductor device

Abstract

An optical semiconductor device includes a stem including a first surface and a second surface on a side opposite to the first surface; a semiconductor laser provided on the first surface side of the stem; a lead pin configured to penetrate through the stem from the first surface to the second surface; and a heat dissipation block including a third surface and a fourth surface on a side opposite to the third surface, the third surface coming into contact with the second surface of the stem, wherein the heat dissipation block includes a groove notching a side surface connecting the third surface and the fourth surface and penetrating through the heat dissipation block from the third surface to the fourth surface, an insulation film is provided on an inside surface of the groove, and the lead pin is inserted into the groove of the heat dissipation block.

Dependencies are inferred from the claim text.