| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the expansion of a microcrack formed on the back face of a crystal growth substrate to improve the reliability and yield of a semiconductor light-emitting device. <P>SOLUTION: A crystal growth surface of a sapphire substrate 204 is overlaid with a semiconductor crystal layer 205 of a multilayer structure. The back face of the sapphire substrate 204 is overlaid by sputtering with a nonmetal layer 2030 of about 10 nm in thickness made of TiO<SB>x</SB>and with a reflective metal layer 2031 of about 10 μm in thickness made of Al. A microcrack opening on the back face of the sapphire substrate 204 is masked with the TiO<SB>x</SB>, which prevents the Al from entering a gap of the microcrack. Because of this, the microcrack opening is not pushed open from inside by the thermal expansion of the Al in a soldering process. This effectively prevents the expansion of the microcrack and spreading of the microcrack to the semiconductor crystal layer 205. <P>COPYRIGHT: (C)2008,JPO&INPIT |
