There is provided a semiconductor laser device which allows a stem body and a heat radiation block to be integrally fabricated even in small-size packages and which is low in price. Portions of leads 3A, 3B protruding on a reference surface side are placed on one side surface side of the heat radiation block 2 on which the semiconductor laser chip is mounted. Further, a cover 6 made of resin which is opened on the beam-output side of the semiconductor laser chip 4 is fixed to the heat radiation block 2 so as to surround the semiconductor laser chip 4 and the portions of the leads 3A, 3B protruding on the reference-surface side in conjunction with the heat radiation block 2.
A semiconductor laser diode device comprises a semiconductor laser diode, a primary lead having a sub-mount for mounting the semiconductor laser diode, at least one secondary lead electrically insulated from the primary lead, a first resin member for integrally fixing the primary lead and the secondary lead while insulating the primary lead from the secondary lead, and a second resin member having an emitting opening through which laser beams generated by the semiconductor laser diode are emitted to the outside, and surrounding the primary lead and the first resin member so as to dissipate heat transferred to the primary lead and the first resin member to the outside.
