Ultraviolet(UV) photodetectors(PDs) have drawn great attention in recent years due to their potential application in civil and military fields. Because of its ultrawide bandgap, low cost, strong radiation hardness, an...Ultraviolet(UV) photodetectors(PDs) have drawn great attention in recent years due to their potential application in civil and military fields. Because of its ultrawide bandgap, low cost, strong radiation hardness, and high thermal and chemical stability with high visible-light transparency, Ga_2O_3 is regarded as the most promising candidate for UV detection.Furthermore, the bandgap of Ga_2O_3 is as high as 4.7–4.9 eV, directly corresponding to the solar-blind UV detection band with wavelength less than 280 nm. There is no need of doping in Ga_2O_3 to tune its bandgap, compared to AlGaN, MgZnO,etc, thereby avoiding alloy composition fluctuations and phase separation. At present, solar-blind Ga_2O_3 photodetectors based on single crystal or amorphous Ga_2O_3 are mainly focused on metal–semiconductor–metal and Schottky photodiodes.In this work, the recent achievements of Ga_2O_3 photodetectors are systematically reviewed. The characteristics and performances of different photodetector structures based on single crystal Ga_2O_3 and amorphous Ga_2O_3 thin film are analyzed and compared. Finally, the prospects of Ga_2O_3 UV photodetectors are forecast.展开更多
One judiciously designed strategy of utilizing an ultrathin but conductive Ga_(2)O_(3):Si nanolayer to prepare(AlGa)_(2)O_(3)crystalline film is demonstrated.Benefiting from the existence of Ga_(2)O_(3):Si nanolayer,a...One judiciously designed strategy of utilizing an ultrathin but conductive Ga_(2)O_(3):Si nanolayer to prepare(AlGa)_(2)O_(3)crystalline film is demonstrated.Benefiting from the existence of Ga_(2)O_(3):Si nanolayer,a high-quality(Al_(0.68)Ga_(0.32))_(2)O_(3)sesquioxide film with 68 at.%aluminum was epitaxially grown on sapphire substrates,which was characterized by high-resolution transmission electron microscopy,X-ray photoelectron spectroscopy and X-ray diffraction.Its bandgap was broadened to 6.14 eV,and a vacuum ultraviolet(VUV)(AlGa)_(2)O_(3)/Ga_(2)O_(3):Si photodetector was subsequently fabricated.The detector exhibits a pretty high on-off ratio of about 10^(3),an open-circuit voltage of 1.0 V and a responsivity of 8.1 mA W^(-1) at 0 V bias voltage.The performances imply that the proposed strategy is valuable for improving the quality and also adjusting the bandgap of(AlGa)_(2)O_(3)sesquioxides,which is expected to facilitate their application in VUV photodetection.展开更多
Nonlinear optical(NLO)switchable materials have attracted intense attention because of their promising applications in optoelectronic devices.However,previous studies are mainly limited to molecular-based compounds th...Nonlinear optical(NLO)switchable materials have attracted intense attention because of their promising applications in optoelectronic devices.However,previous studies are mainly limited to molecular-based compounds that usually exhibit narrow bandgaps.Here,we report all-inorganic Li_(9)Na_(3)Rb_(2)(SO_(4))_(7) as an ultrawide-bandgap NLO switchable material.展开更多
Ultrawide bandgap semiconductor,e.g.,diamond,is considered as the next generation of semiconductor.Here,a new orthorhombic carbon allotrope(P2_(1)2_(1)2_(1)-C16)with ultrawide bandgap and ultra-large hardness is ident...Ultrawide bandgap semiconductor,e.g.,diamond,is considered as the next generation of semiconductor.Here,a new orthorhombic carbon allotrope(P2_(1)2_(1)2_(1)-C16)with ultrawide bandgap and ultra-large hardness is identified.The stability of the newly designed carbon is confirmed by the energy,phonon spectrum,ab-initio molecular dynamics and elastic constants.The hardness ranges from 88 GPa to 93 GPa according to different models,which is comparable to diamond.The indirect bandgap reaches 6.23 eV,which is obviously larger than that of diamond,and makes it a promising ultra-wide bandgap semiconductor.Importantly,the experimental possibility is confirmed by comparing the simulated X-ray diffraction with experimental results,and two hypothetical transformation paths to synthesize it from graphite are proposed.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61521064,61522408,61574169,61334007,61474136,and 61574166)the Ministry of Science and Technology of China(Grant Nos.2018YFB0406504,2016YFA0201803,2016YFA0203800,and 2017YFB0405603)+1 种基金the Key Research Program of Frontier Sciences of Chinese Academy of Sciences(Grant Nos.QYZDB-SSW-JSC048 and QYZDY-SSW-JSC001)the Beijing Municipal Science and Technology Project,China(Grant No.Z171100002017011)
文摘Ultraviolet(UV) photodetectors(PDs) have drawn great attention in recent years due to their potential application in civil and military fields. Because of its ultrawide bandgap, low cost, strong radiation hardness, and high thermal and chemical stability with high visible-light transparency, Ga_2O_3 is regarded as the most promising candidate for UV detection.Furthermore, the bandgap of Ga_2O_3 is as high as 4.7–4.9 eV, directly corresponding to the solar-blind UV detection band with wavelength less than 280 nm. There is no need of doping in Ga_2O_3 to tune its bandgap, compared to AlGaN, MgZnO,etc, thereby avoiding alloy composition fluctuations and phase separation. At present, solar-blind Ga_2O_3 photodetectors based on single crystal or amorphous Ga_2O_3 are mainly focused on metal–semiconductor–metal and Schottky photodiodes.In this work, the recent achievements of Ga_2O_3 photodetectors are systematically reviewed. The characteristics and performances of different photodetector structures based on single crystal Ga_2O_3 and amorphous Ga_2O_3 thin film are analyzed and compared. Finally, the prospects of Ga_2O_3 UV photodetectors are forecast.
基金supported by the National Natural Science Foundation of China(91833301 and 61427901)Guangdong Natural Science Funds for Distinguished Young Scholars(2021B1515020105)Guangdong Basic and Applied Basic Research Foundation(2019A1515110916)。
文摘One judiciously designed strategy of utilizing an ultrathin but conductive Ga_(2)O_(3):Si nanolayer to prepare(AlGa)_(2)O_(3)crystalline film is demonstrated.Benefiting from the existence of Ga_(2)O_(3):Si nanolayer,a high-quality(Al_(0.68)Ga_(0.32))_(2)O_(3)sesquioxide film with 68 at.%aluminum was epitaxially grown on sapphire substrates,which was characterized by high-resolution transmission electron microscopy,X-ray photoelectron spectroscopy and X-ray diffraction.Its bandgap was broadened to 6.14 eV,and a vacuum ultraviolet(VUV)(AlGa)_(2)O_(3)/Ga_(2)O_(3):Si photodetector was subsequently fabricated.The detector exhibits a pretty high on-off ratio of about 10^(3),an open-circuit voltage of 1.0 V and a responsivity of 8.1 mA W^(-1) at 0 V bias voltage.The performances imply that the proposed strategy is valuable for improving the quality and also adjusting the bandgap of(AlGa)_(2)O_(3)sesquioxides,which is expected to facilitate their application in VUV photodetection.
基金supported by the National Nature Science Foundation of China(21833010,61975207,21622101,21921001,21525104,and 51662013)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB20000000 and XDB20010200)+5 种基金the Natural Science Foundation of Fujian Province(2018H0047)the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(ZDBS-LY-SLH024)the Natural Science Foundation of Guangxi Province(2018GXNSFDA281015)the National Key Research and Development Program of China(2019YFA0210400)Key Laboratory of Functional Crystals and Laser Technology,TIPC,CAS(FCLT 202003)Key Laboratory of New Processing Technology for Nonferrous Metal&Materials,Ministry of Education/Guangxi Key Laboratory of Optical and Electronic Materials and Devices(20KF-11).
文摘Nonlinear optical(NLO)switchable materials have attracted intense attention because of their promising applications in optoelectronic devices.However,previous studies are mainly limited to molecular-based compounds that usually exhibit narrow bandgaps.Here,we report all-inorganic Li_(9)Na_(3)Rb_(2)(SO_(4))_(7) as an ultrawide-bandgap NLO switchable material.
基金supported by the National Natural Science Foundation of China(No.51875269)the Startup Foundation of Jiangsu University of Science and Technology(No.202100000135).
文摘Ultrawide bandgap semiconductor,e.g.,diamond,is considered as the next generation of semiconductor.Here,a new orthorhombic carbon allotrope(P2_(1)2_(1)2_(1)-C16)with ultrawide bandgap and ultra-large hardness is identified.The stability of the newly designed carbon is confirmed by the energy,phonon spectrum,ab-initio molecular dynamics and elastic constants.The hardness ranges from 88 GPa to 93 GPa according to different models,which is comparable to diamond.The indirect bandgap reaches 6.23 eV,which is obviously larger than that of diamond,and makes it a promising ultra-wide bandgap semiconductor.Importantly,the experimental possibility is confirmed by comparing the simulated X-ray diffraction with experimental results,and two hypothetical transformation paths to synthesize it from graphite are proposed.
