Light extraction efficiency enhancement of 265nm UVC-LED with Micro-array structure

摘要

It is well known that DUV-LED with AlGaN-based has a wavelength ranging from 200 to 300 nm is major adopted with an inorganic hermetic packaging technology . Importantly, silica glass can prevent ultraviolet aging and apply to hermetic package at the same time . However , compared to the bare-chip packaging , quartz will give rise to Fresnel reflection losses because of the difference refractive index between the air and the silica glass , which reduces the luminous flux of the UVC-LED. Therefore, it is urgent to search for a method to reduce the reflection losses and to increase the UVC luminous flux. In this paper, several micro-processing methods for quartz lenses are proposed. The Monte-Carlo method is used to trace ultraviolet light rays, and numerical simulations are performed based on the rigorous coupled wave analysis method . Analyze the effects of different array micro-processing structures on UV light . The results show that single-sided micro-processing arrays has a significant increase in the intensity of 265 nm UVC-LED . As the size of micro-processing in inner quartz increases , the lens has an enhancement effect on ultraviolet light. In addition, micro-processing can enhance the concentration of light and increase the intensity of ultraviolet effectively light.