Multicolor photodetection,essential for applications in infrared imaging,environ-mental monitoring,and spectral analysis,is often limited by the narrow bandgaps of conventional materials,which struggle with speed,sens...Multicolor photodetection,essential for applications in infrared imaging,environ-mental monitoring,and spectral analysis,is often limited by the narrow bandgaps of conventional materials,which struggle with speed,sensitivity,and room-temperature operation.We address these issues with a multicolor uncooled photo-detector based on an asymmetric Au/SnS/Gr vertical heterojunction with inversion-symmetry breaking.This design utilizes the complementary bandgaps of SnS and graphene to enhance the efficiency of carriers'transport through consis-tently oriented built-in electric fields,achieving significant advancements in direc-tional photoresponse.The device demonstrates highly sensitive photoelectric detection performance,such as a responsivity(R)of 55.4–89.7 A W^(–1)with rapid response times of approximately 104μs,and exceptional detectivity(D^(*))of 2.38×10^(10)Jones-8.19×10^(13)Jones from visible(520 nm)to infrared(2000 nm)light,making it suitable for applications demanding an imaging resolution of-0.5 mm.Additionally,the comparative analysis reveals that the asymmetric ver-tical heterojunction outperforms its counterparts,exhibiting approximately 9-fold the photoresponse of symmetric vertical heterojunction and almost 100-fold that of symmetric horizontal heterojunction.This highly sensitive multicolor detector holds significant promise for applications in advanced versatile object detection and imaging recognition systems.展开更多
We propose a periodic structure as an extra absorption layer（i.e., absorber） based on surface plasmon resonance effects, enhancing dual-band absorption in both middle wavelength infrared（MWIR） and long wavelength ...We propose a periodic structure as an extra absorption layer（i.e., absorber） based on surface plasmon resonance effects, enhancing dual-band absorption in both middle wavelength infrared（MWIR） and long wavelength infrared（LWIR）regions. Periodic gold disks are selectively patterned onto the top layer of suspended SiN/VO_2/SiN sandwich-structure.We employ the finite element method to model this structure in COMSOL Multiphysics including a proposed method of modulating the absorption peak. Simulation results show that the absorber has two absorption peaks at wavelengths λ =4.8 μm and λ = 9 μm with the absorption magnitudes more than 0.98 and 0.94 in MWIR and LWIR regions, respectively. In addition, the absorber achieves broad spectrum absorption in LWIR region, in the meanwhile, tunable dual-band absorption peaks can be achieved by variable heights of cavity as well as diameters and periodicity of disk. Thus, this designed absorber can be a good candidate for enhancing the performance of dual band uncooled infrared detector, furthermore, the manufacturing process of cavity can be easily simplified so that the reliability of such devices can be improved.展开更多
Vanadium dioxide with superior thermal sensitivity is one of the most preferred materials used in microbolometer,and the B phase of VO_(2) is particularly prominent.However,conventional VO_(2)(B)undergoes low temperat...Vanadium dioxide with superior thermal sensitivity is one of the most preferred materials used in microbolometer,and the B phase of VO_(2) is particularly prominent.However,conventional VO_(2)(B)undergoes low temperature-coefficient of resistance(TCR)values and large resistances.In this paper,simple controllable composite films of vertical graphene nanowalls/VO_(2)(B)(i.e.,VGNWs/VO_(2)(B))with a suitable square resistance(12.98 kU)and a better temperature-coefficient of resistance(TCR)(-3.2%/K)were prepared via low pressure chemical vapor deposition.The VGNWs can provide a fast channel for electron transport and enhance the conductivity of VO_(2)(B).This preparation method can provide a low cost,facile and simple pathway for the design and fabrication of high performance VO_(2)(B)thin films with superior electrical properties for its application in uncooled infrared detectors.展开更多
This paper introduces a low-cost infrared absorbing structure for an uncooled infrared detector in a standard 0.5 m CMOS technology and post-CMOS process. The infrared absorbing structure can be created by etching the...This paper introduces a low-cost infrared absorbing structure for an uncooled infrared detector in a standard 0.5 m CMOS technology and post-CMOS process. The infrared absorbing structure can be created by etching the surface sacrificial layer after the CMOS fabrication, without any additional lithography and deposition procedures. An uncooled infrared microbolometer is fabricated with the proposed infrared absorbing structure.The microbolometer has a size of 6565 m2and a fill factor of 37.8%. The thermal conductance of the microbolometer is calculated as 1.3310 5W/K from the measured response to different heating currents. The fabricated microbolometer is irradiated by an infrared laser, which is modulated by a mechanical chopper in a frequency range of 10–800 Hz. Measurements show that the thermal time constant is 0.995 ms and the thermal mass is 1.3210 8J/K. The responsivity of the microbolometer is about 3.03104V/W at 10 Hz and the calculated detectivity is 1.4108cm Hz1=2/W.展开更多
基金National Key Research and Development Program of China,Grant/Award Number:2023YFA1406900Strategic Priority Research Program(B)of Chinese Academy of Sciences,Grant/Award Numbers:XDB0580000,GJ0090406,XDB43010200+7 种基金National Natural Science Foundation of China,Grant/Award Numbers:62222514,62350073,U2341226,61991440,91850208,62204249,62005249Youth Innovation Promotion Association of Chinese Academy of Sciences,Grant/Award Number:Y2021070Shanghai Science and Technology Committee,Grant/Award Numbers:23ZR1482000,22JC1402900Shanghai Municipal Science and Technology Major Project,Grant/Award Number:2019SHZDZX01Open Fund of State Key Laboratory of Infrared Physics,Grant/Award Number:SITP-NLIST-YB-2023-13Natural Science Foundation of Zhejiang Province,Grant/Award Numbers:LZ24F050006,LQ20F050005,LR22F050004Excellent Postdoctoral Research Projects of Zhejiang Province,Grant/Award Number:ZJ2021019Research Funds of Hangzhou Institute for Advanced Study,UCAS,Grant/Award Numbers:B02006C019025,B02006C021010。
文摘Multicolor photodetection,essential for applications in infrared imaging,environ-mental monitoring,and spectral analysis,is often limited by the narrow bandgaps of conventional materials,which struggle with speed,sensitivity,and room-temperature operation.We address these issues with a multicolor uncooled photo-detector based on an asymmetric Au/SnS/Gr vertical heterojunction with inversion-symmetry breaking.This design utilizes the complementary bandgaps of SnS and graphene to enhance the efficiency of carriers'transport through consis-tently oriented built-in electric fields,achieving significant advancements in direc-tional photoresponse.The device demonstrates highly sensitive photoelectric detection performance,such as a responsivity(R)of 55.4–89.7 A W^(–1)with rapid response times of approximately 104μs,and exceptional detectivity(D^(*))of 2.38×10^(10)Jones-8.19×10^(13)Jones from visible(520 nm)to infrared(2000 nm)light,making it suitable for applications demanding an imaging resolution of-0.5 mm.Additionally,the comparative analysis reveals that the asymmetric ver-tical heterojunction outperforms its counterparts,exhibiting approximately 9-fold the photoresponse of symmetric vertical heterojunction and almost 100-fold that of symmetric horizontal heterojunction.This highly sensitive multicolor detector holds significant promise for applications in advanced versatile object detection and imaging recognition systems.
基金supported by the One Hundred Talents Program of the Chinese Academy of Sciencesthe National Natural Science Foundation of China(Grant Nos.61376083 and 61307077)+1 种基金the China Postdoctoral Science Foundation(Grant Nos.2013M530613 and 2015T80080)the Guangxi Key Laboratory of Precision Navigation Technology and Application(Grant Nos.DH201505,DH201510,and DH201511)
文摘We propose a periodic structure as an extra absorption layer（i.e., absorber） based on surface plasmon resonance effects, enhancing dual-band absorption in both middle wavelength infrared（MWIR） and long wavelength infrared（LWIR）regions. Periodic gold disks are selectively patterned onto the top layer of suspended SiN/VO_2/SiN sandwich-structure.We employ the finite element method to model this structure in COMSOL Multiphysics including a proposed method of modulating the absorption peak. Simulation results show that the absorber has two absorption peaks at wavelengths λ =4.8 μm and λ = 9 μm with the absorption magnitudes more than 0.98 and 0.94 in MWIR and LWIR regions, respectively. In addition, the absorber achieves broad spectrum absorption in LWIR region, in the meanwhile, tunable dual-band absorption peaks can be achieved by variable heights of cavity as well as diameters and periodicity of disk. Thus, this designed absorber can be a good candidate for enhancing the performance of dual band uncooled infrared detector, furthermore, the manufacturing process of cavity can be easily simplified so that the reliability of such devices can be improved.
基金supported by the jointed foundation from National Natural Science Foundation of China and the big science facility of Chinese Academy of Sciences(No.U1632108).
文摘Vanadium dioxide with superior thermal sensitivity is one of the most preferred materials used in microbolometer,and the B phase of VO_(2) is particularly prominent.However,conventional VO_(2)(B)undergoes low temperature-coefficient of resistance(TCR)values and large resistances.In this paper,simple controllable composite films of vertical graphene nanowalls/VO_(2)(B)(i.e.,VGNWs/VO_(2)(B))with a suitable square resistance(12.98 kU)and a better temperature-coefficient of resistance(TCR)(-3.2%/K)were prepared via low pressure chemical vapor deposition.The VGNWs can provide a fast channel for electron transport and enhance the conductivity of VO_(2)(B).This preparation method can provide a low cost,facile and simple pathway for the design and fabrication of high performance VO_(2)(B)thin films with superior electrical properties for its application in uncooled infrared detectors.
基金Project supported by the National Natural Science Foundation of China(Nos.60806038,61131004,61274076)the National HighTechnology Research and Development Program of China(Nos.2006AA040102,2006AA040106)
文摘This paper introduces a low-cost infrared absorbing structure for an uncooled infrared detector in a standard 0.5 m CMOS technology and post-CMOS process. The infrared absorbing structure can be created by etching the surface sacrificial layer after the CMOS fabrication, without any additional lithography and deposition procedures. An uncooled infrared microbolometer is fabricated with the proposed infrared absorbing structure.The microbolometer has a size of 6565 m2and a fill factor of 37.8%. The thermal conductance of the microbolometer is calculated as 1.3310 5W/K from the measured response to different heating currents. The fabricated microbolometer is irradiated by an infrared laser, which is modulated by a mechanical chopper in a frequency range of 10–800 Hz. Measurements show that the thermal time constant is 0.995 ms and the thermal mass is 1.3210 8J/K. The responsivity of the microbolometer is about 3.03104V/W at 10 Hz and the calculated detectivity is 1.4108cm Hz1=2/W.
