The Ce （x nm）/Au （15 nm） stacked layers were used as semitransparent cathodes in the top-emission organic light emitting devices （TOLEDs） fabricated on a p-type silicon anodes and substrate,where x varies from 4...The Ce （x nm）/Au （15 nm） stacked layers were used as semitransparent cathodes in the top-emission organic light emitting devices （TOLEDs） fabricated on a p-type silicon anodes and substrate,where x varies from 4 to 16.The consequence of the Ce layer thickness on transmittance and the device performance were studied when the organic layers NPB （60 nm）/ALQ （60 nm） were kept unchanged,where NPB was N,N＇-bis-（1-naphthl）-diphenyl-1,1＇-biphenyl-4,4＇-diamine,and AlQ is tris-（8-hydroxyquinoline） aluminum.The cathode of Ce （11 nm）/Au （15 nm） has a transparency of 46%,and the TOLED with it achieves the highest luminescence efficiencies：a current efficiency of 0.91 cd/A at 13.7 V and a peak power efficiency of 0.28 lm/W at 9 V.The turn-on voltage is 3.0 V.The Ce/Au cathode is both chemically and electrically stable.展开更多
Transparent organic light-emitting devices(TOLEDs) based on a stacked alloy cathode of LiF/Al:Ag are investigated. The devices have a structure of indium-tin-oxide(ITO)/4,4′,4′′-Tris[2-naphthyl(phenyl)amino]triphen...Transparent organic light-emitting devices(TOLEDs) based on a stacked alloy cathode of LiF/Al:Ag are investigated. The devices have a structure of indium-tin-oxide(ITO)/4,4′,4′′-Tris[2-naphthyl(phenyl)amino]triphenylamine(2T-NATA)(25 nm)/N,N'-Di-[(1-naphthyl)-N,N'-diphenyl]-1,1'-biphenyl-4,4'-diamine(NPB)(40 nm)/tris-(8-hydroxyquinoline) aluminum(Al_(q_3))(50 nm)/LiF(1 nm)/Al:Ag(1:3)(x), where the thicknesses of cathode metal layers(Al:Ag) are adjusted, respectively, from 70 nm to 100 nm. In the experiment, it is found that the Li F(1 nm)/Al:Ag(1:3)(75 nm) has good electron injection efficiency. Compared with an Al-only cathode, the turn-on voltage is lowered. At the voltage of 10 V, the luminances for bottom emission from ITO anode side and top emission from metal cathode side are 2 459 cd/m^2 and 1 729 cd/m^2, respectively. Thanks to electron injection enhancement by using Al:Ag cathode, we can obtain a better energy level matching between the cathode and the organic layer, thus the devices have lower turn-on voltage and higher luminance. The total transmittance of the devices can achieve about 40% at the wavelength of 550 nm.展开更多
Prticle-in-cell（PIC） simulations demonstrated that,when the relativistic magnetron with diffraction output（MDO） is applied with a 410 kV voltage pulse,or when the relativistic magnetron with radial output is appli...Prticle-in-cell（PIC） simulations demonstrated that,when the relativistic magnetron with diffraction output（MDO） is applied with a 410 kV voltage pulse,or when the relativistic magnetron with radial output is applied with a 350 kV voltage pulse,electrons emitted from the cathode with high energy will strike the anode block wall.The emitted secondary electrons and backscattered electrons affect the interaction between electrons and RF fields induced by the operating modes,which decreases the output power in the radial output relativistic magnetron by about 15%（10%for the axial output relativistic magnetron）,decreases the anode current by about 5%（5%for the axial output relativistic magnetron）,and leads to a decrease of electronic efficiency by 8%（6%for the axial output relativistic magnetron）.The peak value of the current formed by secondary and backscattered current equals nearly half of the amplitude of the anode current,which may help the growth of parasitic modes when the applied magnetic field is near the critical magnetic field separating neighboring modes.Thus,mode competition becomes more serious.展开更多
文摘The Ce （x nm）/Au （15 nm） stacked layers were used as semitransparent cathodes in the top-emission organic light emitting devices （TOLEDs） fabricated on a p-type silicon anodes and substrate,where x varies from 4 to 16.The consequence of the Ce layer thickness on transmittance and the device performance were studied when the organic layers NPB （60 nm）/ALQ （60 nm） were kept unchanged,where NPB was N,N＇-bis-（1-naphthl）-diphenyl-1,1＇-biphenyl-4,4＇-diamine,and AlQ is tris-（8-hydroxyquinoline） aluminum.The cathode of Ce （11 nm）/Au （15 nm） has a transparency of 46%,and the TOLED with it achieves the highest luminescence efficiencies：a current efficiency of 0.91 cd/A at 13.7 V and a peak power efficiency of 0.28 lm/W at 9 V.The turn-on voltage is 3.0 V.The Ce/Au cathode is both chemically and electrically stable.
基金supported by the National Natural Science Foundation of China(Nos.61076066 and 61605105)Shaanxi Science&Technology Development Program(No.2011KTCQ01-09)
文摘Transparent organic light-emitting devices(TOLEDs) based on a stacked alloy cathode of LiF/Al:Ag are investigated. The devices have a structure of indium-tin-oxide(ITO)/4,4′,4′′-Tris[2-naphthyl(phenyl)amino]triphenylamine(2T-NATA)(25 nm)/N,N'-Di-[(1-naphthyl)-N,N'-diphenyl]-1,1'-biphenyl-4,4'-diamine(NPB)(40 nm)/tris-(8-hydroxyquinoline) aluminum(Al_(q_3))(50 nm)/LiF(1 nm)/Al:Ag(1:3)(x), where the thicknesses of cathode metal layers(Al:Ag) are adjusted, respectively, from 70 nm to 100 nm. In the experiment, it is found that the Li F(1 nm)/Al:Ag(1:3)(75 nm) has good electron injection efficiency. Compared with an Al-only cathode, the turn-on voltage is lowered. At the voltage of 10 V, the luminances for bottom emission from ITO anode side and top emission from metal cathode side are 2 459 cd/m^2 and 1 729 cd/m^2, respectively. Thanks to electron injection enhancement by using Al:Ag cathode, we can obtain a better energy level matching between the cathode and the organic layer, thus the devices have lower turn-on voltage and higher luminance. The total transmittance of the devices can achieve about 40% at the wavelength of 550 nm.
基金supported by National Natural Science Foundation of China(No.61302010)the Foundation of Science and Technology on High Power Microwave Laboratory,Central University Foundation(2013KW07)Work at the University of New Mexico in USA was supportedby ONR Grant N00014-13-1-0565
文摘Prticle-in-cell（PIC） simulations demonstrated that,when the relativistic magnetron with diffraction output（MDO） is applied with a 410 kV voltage pulse,or when the relativistic magnetron with radial output is applied with a 350 kV voltage pulse,electrons emitted from the cathode with high energy will strike the anode block wall.The emitted secondary electrons and backscattered electrons affect the interaction between electrons and RF fields induced by the operating modes,which decreases the output power in the radial output relativistic magnetron by about 15%（10%for the axial output relativistic magnetron）,decreases the anode current by about 5%（5%for the axial output relativistic magnetron）,and leads to a decrease of electronic efficiency by 8%（6%for the axial output relativistic magnetron）.The peak value of the current formed by secondary and backscattered current equals nearly half of the amplitude of the anode current,which may help the growth of parasitic modes when the applied magnetic field is near the critical magnetic field separating neighboring modes.Thus,mode competition becomes more serious.
