Precision self-alignment techniques for optoelectronic integration

Basic techniques used for the integration and precise self-alignment of optoelectronic components are presented. State-of-the-art self-alignment accuracies have been achieved using solder bump arrays for component alignment and etched V-grooves for optical fiber alignment. The self-alignment potential of eutectic tin-silver solder bump arrays to produce sub-quarter-micron alignment precision is demonstrated. The potential for V-groove dimensional control to enable sub-half-micron optical fiber positioning is also demonstrated. Optimal materials and conditions are discussed. Novel fabrication procedures are presented, such as the use of an adhesion layer to facilitate solder reflow and a V-groove planarization process to facilitate planar processing. The combination of these techniques for the integration of optoelectronic components with the provision of mutual alignment between them is also discussed.