| 摘要 |
PURPOSE:To obtain a gallium arsenide phosphide epitaxial wafer having small cracks by forming a step of a crystal mixture ratio in a constant gallium arsenide phosphide mixed crystal layer. CONSTITUTION:A gallium arsenide phosphide epitaxial layer has a gallium arsenide phosphide crystal mixture ratio variable layer 3 and gallium arsenide phosphide constant crystal mixture ratio layers 4, 5 formed in this order on a gallium phosphide single crystalline substrate 1. A step of the crystal mixture ratio is so formed that a crystal mixture ratio of the layer 5 is lower by 0.01-0.05 than that of the surface side from that of the substrate side, i.e., that of the layer 4 in the layers 4, 5. Thus, even if the crystal mixture ratio layer having different lattice constants and thermal expansion coefficients are formed, an internal distortion is small, and cracks of the wafer in the step of manufacturing a light emitting diode can be reduced. |
