Recent，Sun Haiding and Long Shibing's group at the School of Microelectronics, University of Science and Technology of China on the use of sapphire substrate chamfer angle to control quantum wells to achieve three-dimensional carrier confinement，Breakthrough UVLEDImportant progress in luminescence performance。Related research published in《Advanced Functional Materials》。

　　It is understood，Conventional ofUV light sources generally use the excited state of mercury vapor discharge to produce ultraviolet rays，Has high power consumption、Calorific value、Short life、slow response、There are many defects such as hidden dangers。New deep ultraviolet light source uses light-emitting diodes(lightemittingdiode:LED)Light emitting principle，Has many advantages over traditional mercury lamps，The most important advantage is that it does not contain toxic mercury。《Minamata Convention》Implementation，Herald2020Will completely ban the use of mercury-containing ultraviolet lamps，therefore，Developed a new type of environmental protection、Efficient UV light source is urgent。

　　Figure：in0.2with4Deep Ultraviolet Prepared on Beveled Sapphire SubstrateLEDPhotoluminescence spectrum and device schematic，Active region transmission electron microscope showing high resolution multiple quantum well structure，Comparison chart with output power。(Image Source：CUST News)

　　And deep ultraviolet light-emitting diodes based on wide bandgap semiconductor materials have become the only choice for this new application.。This all-solid-state light source system is small、efficient，long life，Just a thumb-sized chip，It can emit more ultraviolet light than a mercury lamp.。however，To achieve UVLEDEfficient lighting is not always so easy。

　　Prof. Haiding Sun and Prof. Long Shibing, School of Microelectronics, University of Science and Technology of China，Cleverly adjusting the bevel angle of the sapphire substrate，Dramatically increase UVLED的IQEAnd device luminous power。The team found，When raising the bevel angle of the substrate，uvLEDInternal dislocations are significantly suppressed，Device luminous intensity is significantly improved。When the chamfered substrate reaches4Degree hours，The intensity of the device's fluorescence spectrum has increased by an order of magnitude，The internal quantum efficiency also reached a record-breaking90%the above。

　　Researchers pass4Epitaxial growth adjustment on a beveled substrate，Researchers fumbled for an optimal structure。The carrier lifetime of this structure exceeds1.60ns，In traditional devices, this value is generally lower than1ns。

　　This research will provide new ideas for the development of highly efficient all-solid-state UV light sources。This idea does not require expensive patterned substrates，No need for complicated epitaxial growth process，It only depends on the adjustment of the bevel angle of the substrate and the matching and optimization of epitaxial growth parameters.，It is hoped that the ultravioletLEDThe luminous characteristics are improved to the same as blue lightLEDComparable height，For high power deep ultravioletLEDLays experimental and theoretical foundation for large-scale applications。

　　Besides，The research work was also obtained by the National Natural Science Foundation of China、Chinese Academy of Sciences、Support from the Chinese University of Science and Technology。Part of the sample processing technology was completed at the University of Science and Technology Micro-nano Research and Manufacturing Center。