Passive self-aligned low-cost packaging of semiconductor laser arrays on Si motherboard

A passive, self-aligned packaging technique for semiconductor laser arrays has been realized. Alignment trenches on the laser chip are used for self-alignment during flip-chip mounting on a silicon motherboard. The use of the etched Si sidewalls for alignment results in a self-positioning effect, reducing the necessary device placing precision, and allowing for large tolerances in the motherboard processing, resulting in low packaging costs. A module with four lasers and integrated monitor diodes has been pigtailed with multimode fibers. Optical mounting excess and differential losses between the channels are <0.5 dB.<>