Facile fabrication of microstructured fluoropolymer encapsulation for light extraction enhancement of deep ultraviolet LEDs

In this paper, we present a simple and green approach to economically fabricate microlens arrays (MLAs) on fluoropolymer encapsulation for deep ultraviolet light-emitting diodes (DUV-LEDs). The MLAs can be fabricated by micromolding water condensing based porous films. By controlling the input current and working time of initiative cooling, uniform porous film with the average height of 1.58 μm and the average bottom-width of 1.12 μm was prepared. The MLA with the aspect ratio (AR) of 1.41 was fabricated by micromolding the porous film templates. In addition, the fluoropolymer encapsulation with MLA was applied for the packaging of DUV-LED. Consequently, the light output power of DUV-LED is enhanced of 7.1% by using this MLA at the driving current of 350 mA.