Chinese researchers succeeded in fabricating and demonstrating an electrically-injected near-ultraviolet laser using AlGaN on Si. Researchers from the Key Laboratory of Nano-devices and Applications, the Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences (CAS), Suzhou, China University of Science and Technology Beijing, and the School of Nano Technology and Nano Bionics, University of Science and Technology of China in Hefei, China reported the development. The researchers detailed their findings in ACS Photonics.
The scientists engineered an Al-composition step down-graded AlN over AlGaN multilayer buffer that was able to accommodate the enormous difference in the coefficient of thermal expansion between AlGaN template and Si substrate, and also decrease the threading dislocation density that the large lattice mismatch caused.
They grew high-quality InGaN/AlGaN quantum wells on top of a crack-free n-AlGaN template. A waveguide and optical cladding layers were placed on either side of these quantum wells in the edge-emitting laser diode.
The researchers pointed to a distinct discontinuity in the slope of light output power plotted as a function of the injection current, a dramatic reduction of the electroluminescence spectral line-width, and an elongated far-field pattern as proof of lasing.
Feng, Meixin, Li, Zengcheng, et al…”Room-Temperature Electrically Injected AlGaN-Based near-Ultraviolet Laser Grown on Si,” ACS Photonics, 2018, 5 (3), pp 699–704. DOI: 10.1021/acsphotonics.7b01215
On May 11, the Nature Publishing Group released Nature Publishing Index 2010 China, remarking “a dramatic rise in the quality of research being published by China”. University of Science and Technology of China is ranked 3rd of TOP 10 Institutions in Index 2010 China.
This article came from News Center of USTC.