The influence of buffer layer growth conditions on the crystal quality and residual stress of GaN film grown on silicon carbide substrate is investigated. It is found that the A1GaN nucleation layer with high growth t...The influence of buffer layer growth conditions on the crystal quality and residual stress of GaN film grown on silicon carbide substrate is investigated. It is found that the A1GaN nucleation layer with high growth temperature can efficiently decrease the dislocation density and stress of the GaN film compared with A1N buffer layer. To increase the light extraction efficiency of GaN-based LEDs on SiC substrate, flip-chip structure and thin film flip-chip structure were designed and optimized. The fabricated blue LED had a maximum wall-plug efficiency of 72% at 80 mA. At 350 mA, the output power, the Vf, the dominant wavelength, and the wall-plug efficiency of the blue LED were 644 roW, 2.95 V, 460 nm, and 63%, respectively.展开更多
Solar-blind ultraviolet photodetectors have many advantages, such as low false alarm rates, the ability to detect weak signals, and high signal-to-noise ratios. Among the various functional solar-blind ultraviolet pho...Solar-blind ultraviolet photodetectors have many advantages, such as low false alarm rates, the ability to detect weak signals, and high signal-to-noise ratios. Among the various functional solar-blind ultraviolet photodetectors, Ga-based alloys of AlGaN and Ga_2O_3 are the most commonly adopted channel semiconductor materials and have attracted extensive research attention in the past decades. This review presents an overview of the recent progress in Ga-based solar-blind photodetectors. In case of AlGaN-based solar-blind ultraviolet photodetectors, the response properties can be improved by optimizing the AlN nucleation layer and designing the avalanche structure. On the other hand, we also discuss the morphology and growth methods of Ga_2O_3 nanomaterials and their effect on the performance of the corresponding solarblind photodetectors. The mechanically exfoliated Ga_2O_3 flakes show good potential for ultraviolet detection. Also, Ga_2O_3 nanoflowers and nanowires reveal perfect response to ultraviolet light. Finally, the challenges and future development of Ga-based functional solar-blind ultraviolet photodetectors are summarized.展开更多
基金Project supported by the National Basic Research Program of China(Grant No.2011CB301904)the National Natural Science Foundation of China(Grant Nos.11134006 and 61327808)
文摘The influence of buffer layer growth conditions on the crystal quality and residual stress of GaN film grown on silicon carbide substrate is investigated. It is found that the A1GaN nucleation layer with high growth temperature can efficiently decrease the dislocation density and stress of the GaN film compared with A1N buffer layer. To increase the light extraction efficiency of GaN-based LEDs on SiC substrate, flip-chip structure and thin film flip-chip structure were designed and optimized. The fabricated blue LED had a maximum wall-plug efficiency of 72% at 80 mA. At 350 mA, the output power, the Vf, the dominant wavelength, and the wall-plug efficiency of the blue LED were 644 roW, 2.95 V, 460 nm, and 63%, respectively.
基金Project supported by the National Key Reserch and Development Program of China(Grant No.2017YFA0305500)the Fund from Science Technology and Innovation Committee of Shenzhen Municipality,China(Grant No.JCYJ20170307093131123)+6 种基金the National Natural Science Foundation of China(Grant No.61504044)the Key Research and Development Program of Shandong Province,China(Grant Nos.2018GGX101027,2017GGX201002,2017CXGC0412,2016ZDJS09A05,and 2016GGX4101)Shandong Provincial Natural Science Foundation,China(Grant No.ZR2017MF037)"Qilu Young Scholar" Program of Shandong UniversityYantai "13th Five-Year" Marine Economic Innovation and Development Demonstration City Project,China(Grant No.YHCXZB-L-201703)the Union Funds of Guizhou Science and Technology Department and Guizhou Minzu University,China(Grant No.LH20157221)the Fundamental Research Funds of Shandong University,China(Grant Nos.2018WLJH87 and 2017TB0021)
文摘Solar-blind ultraviolet photodetectors have many advantages, such as low false alarm rates, the ability to detect weak signals, and high signal-to-noise ratios. Among the various functional solar-blind ultraviolet photodetectors, Ga-based alloys of AlGaN and Ga_2O_3 are the most commonly adopted channel semiconductor materials and have attracted extensive research attention in the past decades. This review presents an overview of the recent progress in Ga-based solar-blind photodetectors. In case of AlGaN-based solar-blind ultraviolet photodetectors, the response properties can be improved by optimizing the AlN nucleation layer and designing the avalanche structure. On the other hand, we also discuss the morphology and growth methods of Ga_2O_3 nanomaterials and their effect on the performance of the corresponding solarblind photodetectors. The mechanically exfoliated Ga_2O_3 flakes show good potential for ultraviolet detection. Also, Ga_2O_3 nanoflowers and nanowires reveal perfect response to ultraviolet light. Finally, the challenges and future development of Ga-based functional solar-blind ultraviolet photodetectors are summarized.
