Failure mechanism of hole formation in laser welding technique for optoelectronic packaging

The characteristics of hole formation in the laser welding technique for optoelectronic packaging have been investigated by metallographic microscopes. The results show that the hole dimension depends on the power density of the laser beam and the hole disappears as the power density falls below 4×10⁵ W/cm². The hole generation between welded sections can cause spatial nonuniformity of solidification-shrinkage during the laser welding process, resulting in the generation of micromovement. Micromovement due to the failure mechanism of the hole formation during the laser welding process may affect the alignment for optoelectronic packages, particularly for single-mode fiber applications. Based on our understanding of laser welding process characteristics, a reliability study of receptacle laser packages is currently under investigation