Surface-emitting laser device and surface-emitting laser array including same

A surface-emitting laser device, comprising:

• a first reflective layer formed of a semiconductor distributed Bragg reflector on a substrate;
• a first cavity spacer layer formed in contact with the first reflective layer;
• an active layer formed in contact with the first cavity spacer layer;
• a second cavity spacer layer formed in contact with the active layer;
• and
• a second reflective layer formed of a semiconductor distributed Bragg reflector in contact with the second cavity spacer layer,
• wherein the first reflective layer includes a plurality of low refractive index layers and the second reflective layer includes a plurality of low refractive index layers;
• and
• a thermal conductivity of a semiconductor material of one of the low refractive index layers of the first reflective layer which one is disposed closest to the active layer is greater than a thermal conductivity of a semiconductor material of one of the low refractive index layers of the second reflective layer which one is disposed closest to the active layer;
• wherein:
• the one of the low refractive index layers of the second reflective layer which one is disposed closest to the active layer includes (AleGa1-e)fIn1-fP (0<e≦1, 0≦f≦1);
• the one of the low refractive index layers of the first reflective layer which one is disposed closest to the active layer includes AlxGa1-xAs (0<x≦1) having the thermal conductivity greater than the thermal conductivity of said (AleGa1-e)fIn1-fP;
• and
• the substrate is connected to a heat sink.