Wirebond-Free LED Arrays With Direct Die Attach

The patent removes wire bonds from the LED packaging structure and replaces them with direct die attach technology. The LED chips are mounted directly onto the substrate using conductive paste or solder bumps, eliminating the wire bond interconnects that cause light absorption and mechanical constraints. This extraction of the harmful wire bond element resolves the contradiction between achieving electrical connection and minimizing light absorption.

The patent divides the LED lighting system into separate functional modules: individual LED chips mounted on a common substrate. Each LED chip can be independently selected, tested, and replaced, while the substrate provides common electrical interconnections and mechanical support. This segmentation allows for simpler manufacturing of individual components while achieving high light output density through optimized chip arrangement and direct die attach technology.

The direct die attach technology enables self-aligned mounting of LED chips onto the substrate. The conductive paste or solder bumps automatically establish both mechanical attachment and electrical connection in a single process step, eliminating the need for separate wire bonding operations. This self-service approach maintains manufacturing yield by reducing process complexity while enabling dense chip packaging for high luminous flux output.