Browsing by Author "Lee, MT"

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Comparison of oxide breakdown progression in ultra-thin oxide SOI and bulk pMOSFETs
(2004)
Chan, CT
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Kuo, CH
;
Tang, CJ
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Chen, MC
;
Wang, TH
Accelerated oxide breakdown progression in ultra-thin oxide (1.4nm) SOI pMOSFETs is observed, as compared to bulk devices. The accelerated progression is explained by the increase of hole stress current as a result of breakdown induced channel carrier heating in a floating-body configuration. Numerical simulation of hole tunneling current and hot carrier luminescence measurement are carried out to justify the proposed theory.
Efficient green coumarin dopants for organic light-emitting devices
(2004-04-15)
Lee, MT
;
Yen, CK
;
Yang, WP
;
Chen, HH
;
Liao, CH
[GRAPHICS] We have synthesized a new green fluorescent dopant C-545P having incorporated five strategically placed "methyl" steric spacers on the julolidyl ring system. C-545P has good thermal properties and photostability, and when fabricated as a dopant in an Alq(3)-hosted OLED device, it shows notable improvement in luminance efficiency and is more resistant to concentration quenching than C-545T, particularly in the doping concentration range between 1 and 2% v/v, while achieving comparable device stability.
Efficient white organic light emitting devices with dual emitting layers
(2005-09-22)
Wu, YS
;
Hwang, SW
;
Chen, HH
;
Lee, MT
;
Shen, WJ
In this paper, a new white organic light-emitting device (OLED) with the structure of indium tin oxide/CFx/1,4-bis[N-(1-naphthyl)-N'-phenylamino]-biphenyl (NPB) (30 mn)NPB: 2,8-di(t-butyl)-5,11-di[4-(t-butyl)phenyl]-6,12-diphenylnaphthacene (20 nm; 1.6 %)/2-methyl-9,10-di(2-naphthyl) anthracene: p-bis(p-NN-di-phenyl-aminostyryl)benzene (40 nm, 3%)/aluminum tris(8-hydroxyquinoline) (20 nm)/LiF (1 nm)/Al (200 mn) has been investigated. The device showed white emission with a high-luminous yield of 9.75 cd/A at 20 mA/cm(2), but its Commission Internationale de l'Eclairage chromaticity coordinates appeared to change from (0.34, 0.42) at 6 mA/cm(2) to (0.27, 0.37) at 200 mA/cm(2) due to the shift of recombination zone. The change of color with drive current was suppressed by introduction of an electron-blocking layer of NPB along with a hole-blocking layer of aluminum (III) bis(2-methyl-8-quinolinato)4-phenylphenolato to the white OLED which successfully confined the recombination site and achieved a luminous yield of 9.9 cd/A at 20 mA/cm(2). (c) 2005 Elsevier B.V All rights reserved.
Highly efficient blue organic light-emitting devices incorporating a composite hole transport layer
(2005-05-16)
Liao, CH
;
Lee, MT
;
Tsai, CH
;
Chen, CH
;
應用化學系
Organic light-emitting devices (OLEDs) incorporating the copper phthalocyanine (CuPc)/N,N-'-bis-(1-naphthyl)-N,N-'-diphenyl-1,1(')-biphenyl-4,4(')-diamine composite hole transport layer have been fabricated. Under optimal condition, the highly efficient sky-blue OLED based on the aminosubstituted distyrylarylene fluorescent dye, doped in the stable diphenyanthracene blue host achieved a luminance efficiency of 16.2 cd/A with a Commission Internationale d' Eclairage (CIE)(x,y) color coordinate of [0.15, 0.29] at 6.4 V (20 mA/cm(2)) and an external quantum efficiency of 8.7%. (c) 2005 American Institute of Physics.
Highly efficient blue organic light-emitting devices incorporating a composite hole transport layer
(2005-05-16)
Liao, CH
;
Lee, MT
;
Tsai, CH
;
Chen, CH
;
應用化學系
Organic light-emitting devices (OLEDs) incorporating the copper phthalocyanine (CuPc)/N,N-'-bis-(1-naphthyl)-N,N-'-diphenyl-1,1(')-biphenyl-4,4(')-diamine composite hole transport layer have been fabricated. Under optimal condition, the highly efficient sky-blue OLED based on the aminosubstituted distyrylarylene fluorescent dye, doped in the stable diphenyanthracene blue host achieved a luminance efficiency of 16.2 cd/A with a Commission Internationale d' Eclairage (CIE)(x,y) color coordinate of [0.15, 0.29] at 6.4 V (20 mA/cm(2)) and an external quantum efficiency of 8.7%. (c) 2005 American Institute of Physics.
Highly efficient deep-blue organic light-emitting devices
(2006-01-01)
Lee, MT
;
Liao, CH
;
Tsai, CH
;
Chen, CH
;
應用化學系
A highly efficient deep-blue organic light-emitting device (OLED) incorporating a novel composite hole-transport layer (c-HTL) and an emitter based on the new non-symmetrical mono(styryl) amine fluorescent dopant in the stable host MADN, which achieved a luminance efficiency of 5.4 cd/A with a Commission Internationale d'Eclairage (CIEx,y) of (0.14, 0.13) and an external quantum efficiency of 5.1% at 20 mA/cm(2) and 6.8 V, is reported. The increased device efficiency is attributed to an improved balance between hole and electron currents in the recombination zone.
Highly efficient yellow and white organic electroluminescent devices doped with 2,8-di(t-butyl)-5,11-di[4-(t-butyl)phenyl]-6,12-diphenylnaphthacene
(2004-11-08)
Liu, TH
;
Wu, YS
;
Lee, MT
;
Chen, HH
;
Liao, CH
We describe the applications of a sterically-hindered yellow dopant, 2,8-di(t-butyl)-5,11-di[4-(t-butyl)phenyl]-6,12-diphenylnaphthacene (TBRb) which, when compared to 5,6,11,12-tetraphenylnaphthacene (Rb) in either tris(8-hydroxyquinolinato)aluminum or 1,4-bis[N-(1-naphthyl)-N-'-phenylamino]-4,4(') diamine (NPB) as host emitter, shows a 50%-34% increase in luminance efficiency over that of Rb device without significantly affecting its color. In addition, we have incorporated the TBRb doped yellow NPB emitter into the two-element white organic light-emitting diodes based on p-bis(p-N,N-di-phenyl-aminostyryl)benzene doped 2-methyl-9,10-di(2-naphthyl) anthracene sky-blue emitter which improved the luminance efficiency by 44% over that of Rb to 12.8 cd/A and 4.3 lm/W at 20 mA/cm(2) with CIEx,y=[0.31,0.38]. (C) 2004 American Institute of Physics.
Highly efficient, deep-blue doped organic light-emitting devices
(2005-10-17)
Lee, MT
;
Liao, CH
;
Tsai, CH
;
Chen, CH
;
應用化學系
All the attributes necessary for good OLED performance (see Figure), namely, high electroluminescence efficiency (5.4 cd A(-1)), long operational lifetime (10 000 h at an initial luminance of 100 cd m(-2)), and deep-blue color (color saturation: (0.14, 0.13)) are demonstrated by an OLED incorporating a novel, composite hole-transport layer and an emitter based on a new mono(styryl)amine dopant in the stable, anthracene-based blue host material, 2-methyl-9,10-di(2-naphthyl)anthracene.
Highly stable organic light-emitting devices with a uniformly mixed hole transport layer
(2005-12-12)
Tsai, CH
;
Liao, CH
;
Lee, MT
;
Chen, CH
;
應用化學系
Highly stable organic light-emitting devices were made by using a uniformly mixed hole transport layer (UM-HTL) composed of a mixture of 2-methyl-9,10-di(2-naphthyl)anthracene (MADN) and N,N-bis(1-naphthyl)-N,N-'-diphenyl,1,1(')-biphenyl-4,4(')-diamine (NPB) in a 3:7 (MADN:NPB) ratio. The lifetime of 10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-benzo[l]-pyrano[6,7,8-ij]quinolizin-11-one doped green device with UM-HTL can be greatly improved to 2.7 times longer than that of the conventional device (NPB based HTL) without impacting on its driving voltage and emissive color significantly. This improvement in stability can be attributed to the fact that the unstable [Alq(3)(+)] species formed by electro-oxidation have been effectively suppressed.
Improved stability of organic electroluminescent devices by doping styrylamines in hole or electron transporting layer
(2005-03-07)
Lee, MT
;
Liao, CH
;
Tsai, CH
;
Chen, CH
;
應用化學系
The stability of green organic electroluminescent devices has been improved by doping styrylamine derivate, p-bis(p-N,N-diphenyl-aminostyryl)benzene (DSA-Ph) in hole or electron transporting layer. Compared with the undoped device, the stability of the electron transporting layer has increased by a factor of 1.8 without affecting the electroluminescence efficiency of 11 cd/A and color (CIEx,y=0.34, 0.62). The enhanced stability is believed to derive from the hole trapping nature of DSA-Ph which can reduce the residual hole carriers in tris(8-hydroquinolinato)aluminum (Alq(3)) and suppress the formation of fluorescent quencher of Alq(3) cationic species. (c) 2005 American Institute of Physics.
Negative substrate bias enhanced breakdown hardness in ultra-thin oxide pMOSFETs
(2003)
Wang, TH
;
Tsai, CW
;
Chen, MC
;
Chan, CT
;
Chiang, HK
Negative substrate bias enhanced breakdown hardness in ultra-thin oxide (1.4nm) pMOS is observed. This result is believed due to the increase of hole stress current during breakdown progression via breakdown induced carrier heating. Numerical analysis of substrate bias effect on hole tunneling current is performed to support the proposed theory. This phenomenon is particularly significant to gate oxide reliability in floating substrate (PD-SOI) or forward-biased substrate devices.
Stable styrylamine-doped blue organic electroluminescent device based on 2-methyl-9,10-di(2-naphthyl)anthracene
(2004-10-11)
Lee, MT
;
Chen, HH
;
Liao, CH
;
Tsai, CH
;
Chen, CH
We have developed a highly efficient and stable blue organic electroluminescent (EL) device based on. a blue fluorescent styrylamine dopant, p-bis(p-N,N-diphenyl-aminostyryl)benzene, in a morphologically stable high band-gap host material, 2-methyl-9, 10-di(2-naphthyl)anthracene, which achieved an EL efficiency of 9.7 cd/A and 5.5 lm/W at 20 mA/cm(2) and 5.7 V,with Commission Internationale d'Eclairage coordinates of (x=0.16, y=0.32). The blue-doped device achieved a half-decay lifetime (t(1/2)) of 46000 h at an initial brightness of 100 cd/m(2). (C) 2004 American Institute of Physics.