AlGaInP-based red miniaturized light-emitting diode(mini-LED)is a key component in realizing a full-color display.One of the main obstacles originates from interfacial recombination at the AlGaInP-SiO_(2)interface,and...AlGaInP-based red miniaturized light-emitting diode(mini-LED)is a key component in realizing a full-color display.One of the main obstacles originates from interfacial recombination at the AlGaInP-SiO_(2)interface,and it is crucial to develop effective surface passivation strategies to achieve higher external quantum efficiency(EQE)in AlGaInP-based red mini-LEDs.Here,we demonstrated AlGaInP-based red flip-chip mini-LEDs with an AlN passivation layer via atomic layer deposition(ALD).Utilizing a Monte Carlo ray tracing method,we investigated the effects of the SiO_(2)passivation layer and the Al N passivation layer on the optical performances of mini-LEDs.Since the refractive index of AlN is between AlGaInP and SiO_(2),the total internal reflection is alleviated and light extraction is enhanced.Unexpectedly,the AlN passivation layer also contributes to improving the current spreading ability of mini-LEDs,which is demonstrated by the near-field light distribution.Benefiting from superior light extraction and improved current spreading,the EQE of the mini-LED with an AlN passivation layer realizes an increment of 16.1%at 5 mA,in comparison to the mini-LED with a SiO_(2)passivation layer.The EQE of miniLEDs with an AlN passivation layer reaches a competitive value of 22.3%at 5 mA,surpassing previously reported AlGaInPbased red mini-LEDs.Moreover,the high temperature-humidity aging test exhibits that the AlN passivation layer effectively enhances the reliability of mini-LEDs.This work provides guidance for high-performance AlGaInP-based red flip-chip miniLEDs design and manufacture.展开更多
Mini-LED backlights,combining color conversion materials with blue mini-LED chips,promise traditional liquid crystal displays(LCDs)with higher luminance,better contrast,and a wider color gamut.However,as color convers...Mini-LED backlights,combining color conversion materials with blue mini-LED chips,promise traditional liquid crystal displays(LCDs)with higher luminance,better contrast,and a wider color gamut.However,as color conversion materials,quantum dots(QDs)are toxic and unstable,whereas commercially available inorganic phosphors are too big in size to combine with small mini-LED chips and also have strong size-dependence of quantum efficiency(QE)and reliability.In this work,we prepare fine-grained Sr_(2)Si_(5)N_(8):Eu^(2+)-based red phosphors with high efficiency and stability by treating commercially available phosphors with ball milling,centrifuging,and acid washing.The particle size of phosphors can be easily controlled by milling speed,and the phosphors with a size varying from 3.5 to 0.7 mm are thus obtained.The samples remain the same QE as the original ones(~80%)even when their particle size is reduced to 3.2-3.5 mm,because they contain fewer surface suspension bond defects.More importantly,SrBaSi_(5)N_(8):Eu^(2+)phosphors show a size-independent thermal quenching behavior and a zero thermal degradation.We demonstrate that red-emitting mini-LEDs can be fabricated by combining the SrBaSi_(5)N_(8):Eu^(2+)red phosphor(3.5 mm in size)with blue mini-LED chips,which show a high external quantum efficiency(EQE)of above 31%and a super-high luminance of 34.3 Mnits.It indicates that fine and high efficiency phosphors can be obtained by the proposed method in this work,and they have great potentials for use in mini-LED displays.展开更多
Mini-LED backlight has emerged as a promising technology for high performance LCDs,yet the massive detection of dead pixels and precise LEDs placement are constrained by the miniature scale of the Mini-LEDs.The high-r...Mini-LED backlight has emerged as a promising technology for high performance LCDs,yet the massive detection of dead pixels and precise LEDs placement are constrained by the miniature scale of the Mini-LEDs.The high-resolution network(Hrnet)with mixed dilated convolution and dense upsampling convolution(MDC-DUC)module and a residual global context attention(RGCA)module has been proposed to detect the quality of vehicular Mini-LED backlights.The proposed model outperforms the baseline networks of Unet,Pspnet,Deeplabv3+,and Hrnet,with a mean intersection over union(Miou)of 86.91%.Furthermore,compared to the four baseline detection networks,our proposed model has a lower root-mean-square error(RMSE)when analyzing the position and defective count of Mini-LEDs in the prediction map by canny algorithm.This work incorporates deep learning to support production lines improve quality of Mini-LED backlights.展开更多
基金supported by the Wuhan Joint Innovation Laboratory of Advanced Display Industry(Grant No.2024010902040449)the National Natural Science Foundation of China(Grant Nos.52075394,52475601)+4 种基金the National Key Research and Development Program of China(Grant Nos.2022YFB3603603,2021YFB3600204)the National Youth Talent Support Program,the Key Research and Development Program of Hubei Province(Grant No.2023BAB137)the Knowledge Innovation Program of Wuhan-Basic Research(Grant No.2023010201010068)the Science and Technology Major Project of Hubei Province(Grant No.2024BAA004)the Science and Technology Major Project of Wuhan(Grant No.2024010702020024)。
文摘AlGaInP-based red miniaturized light-emitting diode(mini-LED)is a key component in realizing a full-color display.One of the main obstacles originates from interfacial recombination at the AlGaInP-SiO_(2)interface,and it is crucial to develop effective surface passivation strategies to achieve higher external quantum efficiency(EQE)in AlGaInP-based red mini-LEDs.Here,we demonstrated AlGaInP-based red flip-chip mini-LEDs with an AlN passivation layer via atomic layer deposition(ALD).Utilizing a Monte Carlo ray tracing method,we investigated the effects of the SiO_(2)passivation layer and the Al N passivation layer on the optical performances of mini-LEDs.Since the refractive index of AlN is between AlGaInP and SiO_(2),the total internal reflection is alleviated and light extraction is enhanced.Unexpectedly,the AlN passivation layer also contributes to improving the current spreading ability of mini-LEDs,which is demonstrated by the near-field light distribution.Benefiting from superior light extraction and improved current spreading,the EQE of the mini-LED with an AlN passivation layer realizes an increment of 16.1%at 5 mA,in comparison to the mini-LED with a SiO_(2)passivation layer.The EQE of miniLEDs with an AlN passivation layer reaches a competitive value of 22.3%at 5 mA,surpassing previously reported AlGaInPbased red mini-LEDs.Moreover,the high temperature-humidity aging test exhibits that the AlN passivation layer effectively enhances the reliability of mini-LEDs.This work provides guidance for high-performance AlGaInP-based red flip-chip miniLEDs design and manufacture.
基金This work is supported by the National Natural Science Foundation of China(Nos.51832005 and 52172157)the Fundamental Research Funds for the Central Universities(No.20720200075)Fujian Provincial Science and Technology Project(Nos.2020I0002 and 2021J01042).
文摘Mini-LED backlights,combining color conversion materials with blue mini-LED chips,promise traditional liquid crystal displays(LCDs)with higher luminance,better contrast,and a wider color gamut.However,as color conversion materials,quantum dots(QDs)are toxic and unstable,whereas commercially available inorganic phosphors are too big in size to combine with small mini-LED chips and also have strong size-dependence of quantum efficiency(QE)and reliability.In this work,we prepare fine-grained Sr_(2)Si_(5)N_(8):Eu^(2+)-based red phosphors with high efficiency and stability by treating commercially available phosphors with ball milling,centrifuging,and acid washing.The particle size of phosphors can be easily controlled by milling speed,and the phosphors with a size varying from 3.5 to 0.7 mm are thus obtained.The samples remain the same QE as the original ones(~80%)even when their particle size is reduced to 3.2-3.5 mm,because they contain fewer surface suspension bond defects.More importantly,SrBaSi_(5)N_(8):Eu^(2+)phosphors show a size-independent thermal quenching behavior and a zero thermal degradation.We demonstrate that red-emitting mini-LEDs can be fabricated by combining the SrBaSi_(5)N_(8):Eu^(2+)red phosphor(3.5 mm in size)with blue mini-LED chips,which show a high external quantum efficiency(EQE)of above 31%and a super-high luminance of 34.3 Mnits.It indicates that fine and high efficiency phosphors can be obtained by the proposed method in this work,and they have great potentials for use in mini-LED displays.
基金National Natural Science Foundation of China(Grant Nos.62275227,62274138,and 11904302)Project of Ministry of Industry and Information Technology of China(Grant No.246)+2 种基金Science and Technology Project of Fujian Province(Grant Nos.2023H4028 and 2023H6038)Key Research and Industrialization Projects of Technological Innovation of Fujian Province(Grant No.2023G043)Shenzhen Science and Technology Program(Grant No.JCYJ20220530143407017).
文摘Mini-LED backlight has emerged as a promising technology for high performance LCDs,yet the massive detection of dead pixels and precise LEDs placement are constrained by the miniature scale of the Mini-LEDs.The high-resolution network(Hrnet)with mixed dilated convolution and dense upsampling convolution(MDC-DUC)module and a residual global context attention(RGCA)module has been proposed to detect the quality of vehicular Mini-LED backlights.The proposed model outperforms the baseline networks of Unet,Pspnet,Deeplabv3+,and Hrnet,with a mean intersection over union(Miou)of 86.91%.Furthermore,compared to the four baseline detection networks,our proposed model has a lower root-mean-square error(RMSE)when analyzing the position and defective count of Mini-LEDs in the prediction map by canny algorithm.This work incorporates deep learning to support production lines improve quality of Mini-LED backlights.
