| 摘要 |
<p>PURPOSE:To increase the thermal conductivity of the entire final layers and to decrease thermal resistance, in an InGaAsP/InP heterojunction light emitting element, by making the final layers a plurality of layers, providing the composition of each layer so that the deviation of a grating constant does not degrade crystal property, and deviating the constant so that the thermal conductivity becomes large. CONSTITUTION:Heat generated in the active layer 11 in a semiconductor laser is escaped to a heat radiating body through a window 18 of SiO2. The thermal resistance becomes 75.1 deg.C/W in the case of a resonator having a length of 200mum. The thermal resistance of only an InGaAsP layer of layers 13, 14, 15 and 16 becomes 58.4 deg.C/W. When this is compared with the case, where, e.g. In0.94Ga0.06As0.29P0.71 layer with a thickness of 0.8mum is provided instead of the layers 13, 14, 15 and 16, the heat resistance only by said In0.94Ga0.06As0.29P0.7, layer is 83.3 deg.C/W. Thus the thermal resistance becomes smaller by 30%. Therefore the upper limit temperature at which continuous oscillation is possible is increased. In addition, since the basic layer of P type InGaAsP is made to be the top layer, a dislocation source, which is the cause of the degradation during the operation, is not introduced into the crystal, when Zn is diffused or Au-Zn is evaporated to form an alloy, and the long, stable operation is made possible.</p> |
