Abstract

This paper provides a brief overview on recent advances in the ultraviolet (UV) photonic materials and devices based upon III-nitrides and the exploitation of chip-level innovation, such as the incorporation of micro-and nano-scale photonic device integration and photonic crystals (PCs), to enhance the extraction efficiency of UV light emitting diodes (LEDs). By inserting a high quality AlN epilayer that serves as a template for the subsequent growth of AlGaN alloys and adopting delta-doping scheme, we have greatly reduced the dislocation density and thereby enhanced the doping efficiency. By incorporating AlN and highly conductive n-AlGaN into the actual device structure, we have significantly improved the performance of deep UV LEDs (λ < 300 nm). It was shown that III-nitride PCs provide 3 times enhancement in output power and 4 times enhancement in modulation speed in UV LEDs. The demonstration of photonic band-gap (PBG) materials active in the UV and visible wavelengths opens many new applications.

© 2005 Optical Society of America