Improvement in homogeneity and binning yield of color coordinate by a conformal phosphor sheet technique in white flip-chip LEDs

Abstract

This paper introduces a conformal phosphor sheet technique for white light-emitting diodes based on Si wafer molding. The use of the Si wafer for molding allowed the fabrication of a flipchip-level conformal phosphor sheet with a sidewall structure. This phosphor sheet was processed by placing the phosphor layer onto a chip with uniform thickness, which enabled uniform color conversion and an improved angular color temperature.