Browsing by Author "Hsieh, Tsung-Eong"

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A characterization on emission property of In2O3-SiO2 nanocomposite thin films
(2013-09-01)
Lyu, Yang-Ru
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Hsieh, Tsung-Eong
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材料科學與工程學系
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Department of Materials Science and Engineering
Nanocomposite thin films containing finely dispersed, crystalline In2O3 nanoparticles embedded in SiO2 matrix were fabricated by target-attachment sputtering method. Transmission electron microscopy observed single crystalline In2O3 nanoparticles uniformly embedded in SiO2 matrix of the samples with In2O3 content less than about 60 vol.%. Photoluminescence spectra of the In2O3-SiO2 nanocomposite samples were found to comprise of the blue, green and red emissions. Analytical results indicated that the red and green emissions are correlated to the transitions from conduction band (CB) edge to the In-i(center dot center dot center dot) and V-In''' defect levels, respectively, while the blue emission is originated from the transition from CB edge to V-o(center dot center dot) level or from Vo level to the valence band edge. (C) 2012 Elsevier B.V. All rights reserved.
A study of electromigration behaviors of Ge2Sb2Te5 chalcogenide nano-strips subjected to pulse bias
(2017-07-12)
Huang, Yin-Hsien
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Hsieh, Tsung-Eong
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材料科學與工程學系
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Department of Materials Science and Engineering
Electromigration (EM) behaviors of pristine Ge2Sb2Te5 (GST) and cerium-doped GST (Ce-GST) nano-strips were investigated by the mean-time-to-failure (MTTF) tests under the pulse bias at the conditions of pulse frequency (f) ranging from 1 to 25 MHz and duty cycle ranging from 50% to 80%. Analytical results indicated that, at f greater than 10 MHz, the EM failure of GST nano-strips in pulse bias environment could be depicted by the 'average current model'. With the aid of Black's theory, the activation energies (Ea) of EM process under pulse bias were found to be 0.63 and 0.56 eV for GST and Ce-GST nano-strips, respectively. The Ea values were comparatively smaller than those observed in direct-current MTTF test of GST thin-film samples, implying the enhancement of surface diffusion and skin effect in GST nano-strips. The morphology and composition analyses indicated that the electrostatic and the electron-wind forces might simultaneously involve in the mass transport in GST nano-strips under the test conditions of this study. The composition analysis also revealed that doping could not effectively alleviate the element segregation in GST subjected to electrical bias.
A study of phase transition behaviors of chalcogenide layers using in situ alternative-current impedance spectroscopy
(2012-06-15)
Huang, Yin-Hsien
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Huang, Yu-Jen
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Hsieh, Tsung-Eong
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材料科學與工程學系
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Department of Materials Science and Engineering
Electrical properties of chalcogenide thin films, both pristine Ge2Sb2Te5 (GST) and cerium-doped GST, were investigated by in situ alternative-current (AC) impedance spectroscopy. With the aid of brick-layer model and nano-grain composite model, the roles of grain and grain-boundary on the phase transition of chalcogenides were distinguished and the dominance of grain boundary was observed. Tangent loss behaviors deduced by impedance analysis revealed alien-element doping alters the interfacial polarization and delays the phase-transition rate of GST. Analytical results also illustrated that the in situ AC impedance spectroscopy can be an alternative tool for characterizing the phase-change kinetics of chalcogenides thin films with nano-scale grain sizes. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729528]
A study of ultraviolet-curable organic/inorganic hybrid nanocomposites and their encapsulating applications for organic light-emitting diodes
(2009-06-15)
Chang, Ming-Hua
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Hsieh, Tsung-Eong
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Huang, Bohr-Ran
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Hsieh, Huai-En
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Juang, Fuh-Shyang
UV-curable organic/inorganic hybrid nanocomposites have been successfully synthesized with polymer monomers (tetramethoxysi lane (TMOS)/3-glycidoxypropyl-trimethoxysilane (GPTMS)) nano-fillers (silica/alumina), curing agents (bisphenol A (BPA)), and photoinitiators (triaryl sulfonium hexafluoroantimonate (TSH)) by in situ polymerization. Their thermal stability, coefficient of thermal expansion (CFE), adhesion strength, and gas barrier capability have also been investigated with thermogravimetry analysis (TGA), thermomechanical analysis (TMA), micro-computer universal testing machine and moisture penetration tests. Experimental results indicate that nano-fillers are completely homogeneously dispersed in the polymer matrices and the increase of nano-fillers in the nanocomposites causes the raise of decomposition temperature (Td) as well as gas resistance and the reduction of CTE as well as adhesion strength. Because lab-made organic/inorganic hybrid nanocomposites have been discovered to exhibit excellent gas barrier properties, we have also applied them for the encapsulation of organic light-emitting diodes (OLEDs) and flexible OLEDs. With lab-made nanocomposite cl, the lifetimes of OLEDs and flexible OLEDs can be successfully lengthened to 92 and 36 h, respectively, whereas those of OLEDs and flexible OLEDs without encapsulation are 11 and 7 h, respectively. (C) 2008 Elsevier B.V. All rights reserved.
Advance static random access memory soft fall analysis using nanoprobing and junction delineation transmission electron microscopy
(2007-01-01)
Chang, Wen-Tung
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Hsieh, Tsung-Eong
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Zimmermann, Gunnar
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Wang, Lars
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材料科學與工程學系
Nanoprobing was used to analyze the soft cell failure of submicron static random access memory (SRAM) at cell level by means of a Zyvex S 100 nanomanipulator system inside a scanning electron microscopy and a multiprobe atomic force probe system, respectively. For the 256 Kbyte dual-port SRAM block, the failure areas exhibit very weak positive-channel field effect transistor drain currents of several magnitudes below the target values, while the drain currents of negative-channel field effect transistor cell transistors are in the expected range. A junction delineation or junction stain was applied to transmission electron microscopy samples to delineate areas with different doping levels so as to make the fail sites visible. Due to the difference in etching behavior of the fail and a reference area, missing lightly doped drain extensions and a partially blocked source/drain implantation were identified as the failure mechanisms. (c) 2007 American Vacuum Society.
An Investigation of Diffusion Barrier Characteristics of an Electroless Co(W, P) Layer to Lead-Free SnBi Solder
(2011-03-01)
Pan, Hung-Chun
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Hsieh, Tsung-Eong
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材料科學與工程學系
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Department of Materials Science and Engineering
Diffusion barrier characteristics for eutectic SnBi solder/electroless Co(W,P) couples were investigated via liquid-state aging at 250 degrees C and solid-state aging at 120 degrees C. At the couple interface, CoSn(3) intermetallic compound (IMC) spallation was observed for the SnBi/amorphous Co(W,P) couple subjected to liquid-state aging. In contrast, no spallation of IMCs was observed for the SnBi/amorphous Co(W,P) couples subjected to solid-state aging. For the SnBi/polycrystalline Co(W,P) couple, a thick IMC layer was observed adjacent to a tungsten-enriched amorphous interfacial layer regardless of aging conditions. IMC formation in all samples indicated that Co(W,P) is essentially a sacrificial barrier to SnBi solder. However, amorphous Co(W,P) might also exhibit stuffed-type barrier behavior due to its relatively high phosphorus (P) content. Analytical results indicated that the P content in Co(W,P) is a crucial factor affecting the structural evolution at the SnBi/electroless Co(W,P) interface.
BGA cutter improvement utilizing nano-TiAlN coating layers synthesized by cathodic arc ion plating process
(2009-12-25)
Huang, Sung-Hsiu
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Hsieh, Tsung-Eong
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Chen, Jia-Wei
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材料科學與工程學系
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Department of Materials Science and Engineering
Ti/Al targets with various concentration ratios, Ti(0.75)Al(0.25), Ti(0.66)Al(0.33), Ti(0.5)Al(0.5) and Ti(0.33)Al(0.66) were used in a filtered cathodic arc ion plating system (FCAIP) to deposit the multilayer TiAlN films on Si wafer substrates and WC cermet ball grid array (BGA) cutters at various modulation wavelengths. Transmission electron microscopy (TEM), nanoindentation and BGA router were used to evaluate the characteristics of TiAlN layers and the performance of BGA cutters. TEM analysis revealed that the modulation wavelengths of deposited layers are less than 10 nm at various rotation speeds in FCAIP chamber and the crystal structure of TiAlN layer with the maximum hardness is NaCl-B1 structure using the Ti(0.5)Al(0.5) target The maximum hardness of multiple TiAlN layers measured by nanoindentation was 43 GPa,while the TiAlN monolayer exhibited the maximum hardness of 30 GPa in the same chamber. The TiAlN-coated BGA cutter deposited at the optimized condition exhibited a twice longer life and a higher machining speed in comparison with the conventional cutter. (C) 2009 Elsevier B.V. All rights reserved.
Characteristics of AgInSbTe-SiO(2) nanocomposite thin film applied to nonvolatile floating gate memory devices
(2010-10-22)
Chiang, Kuo-Chang
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Hsieh, Tsung-Eong
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材料科學與工程學系
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Department of Materials Science and Engineering
Nanocomposite thin films containing AgInSbTe (AIST) particles embedded in an SiO(2) matrix was prepared by sputtering deposition and its feasibility for nonvolatile floating gate memory (NFGM) was investigated. The sample subjected to a 400 degrees C annealing exhibited a distinct hysteresis memory window (Delta V(FB)) shift = 6.6 V and charge density = 5.2 x 10(12) cm(-2) after +/- 8 V gate voltage sweep. Electrical measurement revealed the current transport is via the Schottky emission in low applied field and the space-charge-limited conduction mechanism in high applied field in the samples, regardless of their thermal history. Transmission electron microscopy and x-ray photoelectron spectroscopy indicated that the metallic Sb(2)Te nanocrystals (NCs) with diameters about 5-7 nm dispersed in a nanocomposite layer may serve as the discrete charge-storage traps for nonvolatile memory. Analytical results illustrate the utilization of an AIST-SiO(2) nanocomposite layer as the core structure of NFGM devices is able to simplify the device structure and fabrication process.
Characteristics of AgInSbTe-SiO2 nanocomposite thin film applied to nonvolatile floating gate memory devices
(2010-10-22)
Chiang, Kuo-Chang
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Hsieh, Tsung-Eong
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材料科學與工程學系
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Department of Materials Science and Engineering
Nanocomposite thin films containing AgInSbTe (AIST) particles embedded in an SiO2 matrix was prepared by sputtering deposition and its feasibility for nonvolatile floating gate memory (NFGM) was investigated. The sample subjected to a 400 degrees C annealing exhibited a distinct hysteresis memory window (Delta V-FB) shift = 6.6 V and charge density = 5.2 x 10(12) cm(-2) after +/- 8 V gate voltage sweep. Electrical measurement revealed the current transport is via the Schottky emission in low applied field and the space-charge-limited conduction mechanism in high applied field in the samples, regardless of their thermal history. Transmission electron microscopy and x-ray photoelectron spectroscopy indicated that the metallic Sb2Te nanocrystals (NCs) with diameters about 5-7 nm dispersed in a nanocomposite layer may serve as the discrete charge-storage traps for nonvolatile memory. Analytical results illustrate the utilization of an AIST-SiO2 nanocomposite layer as the core structure of NFGM devices is able to simplify the device structure and fabrication process.
Characteristics of Cu2ZnSn(SXSe1-x)(4) thin-film solar cells prepared by sputtering deposition using single quaternary Cu2ZnSnS4 target followed by selenization/sulfurization treatment
(2017-04)
Lin, Yu-Pin
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Hsieh, Tsung-Eong
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Chen, Yen-Chih
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Huang, Kun-Ping
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材料科學與工程學系
This work demonstrates the preparation of Cu2ZnSn(SxSe1-x)(4)(CZTSSe) thin films by sputtering deposition using single-phase Cu2ZnSnS4 (CZTS) target followed by selenization/sulfurization treatment at 570 degrees C for 1 h. Afterward, the CZTSSe thin-film solar cell samples with the Mo/CZTSSe/CdS/i-ZnO/IZO/Al structure were prepared and their performances were evaluated. By varying the ratio of Se and S powders of heat treatment, the Cu-poor/Zn-rich CZTSSe layers with S/(S+Se) ratio in the range of 0.21-1 were achieved and the CZTSSe layers were the mixture of kesterite CZTS and CZTSe phases as revealed by the x-ray diffraction and the Raman spectroscopy analyses. UV-NIR spectroscopy indicated the bandgaps of CZTSSe samples are in the range of 1.06-1.45 eV when the S/(S+Se) ratio varies from 0.21 to 1. Hall measurement observed the best transport property with p-type carrier concentration of 2.17x10(15) cm(-3) and mobility of 8.9 cm(2) V-1 sec(-1) in CZTSSe layer with S/(S+Se) ratio of 0.46. Under the AM1.5 illumination condition, the CZTSSe thin-film solar cell sample with S/(S+Se) ratio of 0.46 exhibited the best performance with open-circuit voltage of 0.506 V, short-circuit current density of 27.41 mA/cm(2), fill factor of 50% and conversion efficiency of 6.9%.
Characterization of write-once blu-ray disk containing Cu-Al/Si recording layer using transmission electron microscopy
(2011-02-28)
Mai, Hung-Chuan
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Hsieh, Tsung-Eong
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Jeng, Shiang-Yao
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材料科學與工程學系
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Department of Materials Science and Engineering
Microstructure change in write-once blu-ray disk containing Cu-Al/Si recording layer was investigated by transmission electron microscopy. Nanoscale crystallites were found to comprise of the Cu-Al/Si recording layer before and after signal writing and the energy dispersive spectroscopy revealed insignificant composition fluctuation in disk sample. Analytical results indicated the signal properties of disk samples are correlated with a moderate improvement of crystallinity and the formation of Cu and Si solid-solution phases due to element mixing in mark area, rather than the formation of Cu(3)Si silicide and recrystallization of recording layer as reported by previous studies. (C) 2011 American Institute of Physics. [doi:10.1063/1.3560053]
Characterizations and thermal stability improvement of phase-change memory device containing Ce-doped GeSbTe films
(2012-02-29)
Huang, Yu-Jen
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Tsai, Min-Chuan
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Wang, Chiung-Hsin
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Hsieh, Tsung-Eong
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材料科學與工程學系
Phase-transition temperature of GeSbTe (GST) chalcogenide film was drastically increased from 159 to 236 degrees C by cerium (Ce) doping (up to 8.6 at.%) without altering the resistivity property of GST. Grain refinement via the solid-solution mechanism and the amplification of p-type semiconducting behavior in Ce-doped GST were observed. They were correlated with the enhancement of thermal stability and data retention property of GST as revealed by exothermal and isothermal analyses. Phase-change memory (PCM) device characterized at various temperatures revealed an effective thermal stability improvement on the threshold voltage of PCM device by Ce doping. (c) 2011 Elsevier B.V. All rights reserved.
Characterizations of AgInSbTe and Its Nanocomposite Thin Films for Phase-Change Memory Applications
(2010)
Huang, Yu-Jen
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Chung, Tzu-Chin
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Wang, Chiung-Hsin
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Hsieh, Tsung-Eong
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材料科學與工程學系
Phase transition kinetics and microstructures of AgInSbTe (AIST) and AIST-SiO(2) nanocomposite applied to phase-change memories (PCMs) are investigated. In situ electrical property measurement found that the incorporation of SiO(2) escalates the recrystallization temperature (T(x)) of nanocomposite. Both X-ray diffraction and transmission electron microscopy showed grain refinement in the nanocomposite which, in turn, results in an increase of the activation energy (E(a)) of phase transition, as indicated by subsequent Kissinger's analysis. Increase of T(x) and E(a) in the nanocomposite was ascribed to AIST grain refinement and hindrance to grain growth due to dispersed SiO(2) particles in the sample matrix. Johnson-Mehl-Avrami analysis revealed the decrease of Avrami exponent in nanocomposite, implying that the dispersed SiO(2) particles promote the heterogeneous phase transition. Static I-V characteristics and reversible binary switching behavior of PCM devices not only confirmed the results of microstructure characterizations but also illustrated the feasibility of the AIST and its nanocomposite layer for PCM fabrication. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3502531] All rights reserved.
Characterizations of UV-Curable Montmorillonite/Epoxy Nanocomposites Prepared by a Hybrid of Chemical Dispersion and Planetary Mechanical Milling Process
(2012-03-15)
Huang, Heh-Chang
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Huang, Shu-Ping
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Hsieh, Tsung-Eong
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Chen, Chin-Hsin
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材料科學與工程學系
Ammonium salt, [2-(methacyloyloxy)ethyl] trimethylammonium methyl sulfate (MAOTMA), was adopted to modify montmorillonite (MMT) via the cationic exchange process in an acidic environment and a successful enlargement of MMT lamellar spacing from 1.18 to 1.39 nm was identified by x-ray diffraction and Fourier-transform infrared spectroscopy. Accordingly, UV-curable epoxy nanocomposite resins containing various amounts of MAOTMA-modified MMT were prepared with the aid of a planetary mechanical milling process. Transmission electron microscopy revealed a uniform dispersion of exfoliated MMT lamella in epoxy matrix, leading to the distinct improvements on thermal stability and thermal expansion property of nanocomposite samples. Calcium (Ca) test indicated that the good dispersion of MMT fillers in polymer effectively suppresses the moisture permeation in sample matrix. More than twofold increment on retention time of 5% Ca hydrolysis and 20% improvement on the permeation kinetic parameters were observed in the nanocomposite sample containing 8 wt % MMT in comparison with the pristine epoxy sample. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123: 3199-3207, 2012
Colloidal dispersion of nano-scale ZnO powders using amphibious and anionic polyelectrolytes
(2009-04-01)
Ying, Kuo-Liang
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Hsieh, Tsung-Eong
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Hsieh, Yi-Feng
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材料科學與工程學系
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Department of Materials Science and Engineering
This article describes the dispersion of aqueous suspensions containing nano-scale ZnO powder by utilizing a hybrid of chemical dispersant and mechanical mixing/grinding process. The chemical dispersants included anionic or amphibious polyelectrolytes, i.e., sodium salt of polymethylacrylic acid (PMAA-Na) or polyacrylamide/(alpha-N, N-dimethyl-N-acryloyloxyethyl) ammonium ethanate (PDAAE). The optimum critical concentrations for each dispersants to achieve the lowest viscosity, smallest final sediment volume and particle size (d(50)) for the nano-ZnO suspensions, 3 wt.% for PMAA-Na and 5 wt.% for PDAAE, were identified. The finely dispersed nano-ZnO powders were transferred to prepare sputtering target. The root-mean-square roughness (R(Rms)) of thin films deposited by utilizing such a target was found to be 2.05 nm, which was lower than the RRMS of the film (approximate to 27.57 nm) deposited by using a commercial ZnO target comprised of micro-scale granules. (C) 2008 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
Comparison of Different Encapsulating Adhesives to Enhance the Efficiencies and Lifetimes of Polymeric Solar Cells
(2009-04-01)
Chung, Ming-Hua
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Chen, Chen-Ming
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Hsieh, Tsung-Eong
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Tang, Rong-Ming
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Tsai, Yu Sheng
Polymeric solar cells (PSCs) with a derivative of C(60) [[6,6]-phenyl C(61)-butyric acid methyl ester (PCBM)], and 3-hexylthiophene (P3HT) as active layers have been fabricated. The PSC devices were also packaged with glass and novel UV glues to improve their lifetimes and power conversion efficiencies (PCEs). After encapsulation with UV glue I, II, and III, the PCEs of PSCs reached 4, 4.82, and 6%, respectively, and their half-lifetimes increased to 16-18, 26-28, and 90 h, respectively, while the PCEs and half-lifetimes of PSCs without encapsulation were 3.76% and 2.5 h, respectively. (C) 2009 The Japan Society of Applied Physics
Dielectric confinement effect in ZnO quantum dots embedded in amorphous SiO2 matrix
(2007-10-07)
Peng, Yu-Yun
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Hsieh, Tsung-Eong
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Hsu, Chia-Hung
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材料科學與工程學系
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Department of Materials Science and Engineering
The dielectric confinement effect on the blue shift Delta E-g(a) of the ZnO quantum dots (QDs) embedded in the SiO2 matrix is evaluated by applying a multi-shell two-electron system model. The experimental measurement and the calculations of various dielectric structures indicate that the composite matrix structure provides a better estimation of the blue shift of the ZnO QDs-SiO2 system than the multi-shell structure. The proportionality factor x defined in this work exhibits a dependence of the dielectric confinement energy on the specific dimension ratio (the b/a ratio) and the dielectric constant epsilon(matrix) of the outer matrix. The result of the calculation also shows the limit of the two-electron system in estimating the ground-state energy of samples with high dot density. However, the correlation shows the existence of the strong dielectric confinement effect in ZnO QDs-SiO2 thin films and allows a better understanding of the semiconductor QDs-dielectric systems.
Diffusion barrier characteristics and shear fracture behaviors of eutectic PbSn solder/electroless Co(W,P) samples
(2012-01-25)
Pan, Hung-Chun
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Hsieh, Tsung-Eong
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材料科學與工程學系
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Department of Materials Science and Engineering
Diffusion barrier characteristics, activation energy (E(a)) of IMC growth and bonding properties of amorphous and polycrystalline electroless Co(W,P) (termed as alpha-Co(W,P) and poly-Co(W,P)) to eutectic PbSn solder are presented. Intermetallic compound (IMC) spallation and an nano-crystalline P-rich layer were observed in PbSn/alpha-Co(W,P) samples subjected to liquid-state aging at 250 degrees C. In contrast, IMCs resided on the P-rich layer in PbSn/alpha-Co(W,P) samples subjected to solid-state aging at 150 degrees C. Thick IMCs neigh-boring to an amorphous W-rich layer was seen in PbSn/poly-Co(W,P) samples regardless of the aging type. alpha-Co(W,P) was found to be a sacrificial- plus stuffed-type barrier while poly-Co(W,P) is mainly a sacrificial-type barrier. The values of E(a)'s for PbSn/alpha-Co(W,P) and PbSn/poly-Co(W,P) systems were 338.6 and 167.5 kJ/mol, respectively. Shear test revealed the ductile mode dominates the failure in both alpha- and poly-Co(W,P) samples. Analytical results indicated the high P content in electroless layer might enhance the barrier capability but degrade the bonding strength. (C) 2011 Elsevier B.V. All rights reserved.
Diffusion Barrier Characteristics of Electroless Co(W,P) Thin Films to Lead-Free SnAgCu Solder
(2011)
Pan, Hung-Chun
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Hsieh, Tsung-Eong
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材料科學與工程學系
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Department of Materials Science and Engineering
Diffusion barrier and bonding characteristics of amorphous and polycrystalline electroless Co(W,P) layers (alpha-Co(W,P) and poly-Co(W,P)) to SnAgCu (SAC) solder were investigated. In the SAC/alpha-Co(W,P) sample subjected to liquid-state aging at 250 degrees C, the spallation of intermetallic compound (IMC) into solder, a nano-crystalline P-rich layer at SAC/Co(W,P) interface, and the recrystallized Co(W,P) containing Co(2)P precipitates were observed. As to the SAC/alpha-Co(W,P) sample subjected to solid-state aging at 150 degrees C, a thick IMC layer neighboring to the P-rich layer formed at the solder/Co(W,P) interface. Liquid-state aging resulted in an IMC mixture without spallation whereas solid-state aging induced a layer-like IMC in SAC/poly-Co(W,P) samples. Amorphous W-rich layers were also observed in SAC/poly-Co(W,P) samples and it could not inhibit subsequent alloy reactions in the samples. Analytical results indicated the alpha-Co(W,P) is a sacrificial-plus stuffed-type barrier whereas the poly-Co(W,P) is mainly a sacrificial barrier. The activation energies of IMC growth were 110.7 and 81.8 kJ/mol for SAC/alpha-Co(W,P) and SAC/poly-Co(W,P) samples, respectively. High P content in alpha-Co(W,P) was found to degrade the bonding strength to the solder as revealed by the shear test and the control of P content would be a key issue for electroless plating layer applied to under bump metallurgy as the diffusion barrier. (C) 2011 The Electrochemical Society. [DOI: 10.1149/2.004111jes] All rights reserved.
Direct encapsulation of organic light-emitting devices (OLEDs) using photo-curable co-polyacrylate/silica nanocomposite resin
(2007-08-01)
Wang, Yu-Young
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Hsieh, Tsung-Eong
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Chen, I-Ching
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Chen, Chin-Hsin
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材料科學與工程學系
Direct encapsulation of organic light-emitting devices (OLEDs) was realized by using highly transparent, photo-curable co-polyacrylate/silica nanocomposite resin. Feasibility of such a resin for OLED encapsulation was evaluated by physical/electrical property analysis of resins and driving voltage/luminance/lifetime measurement of OLEDs. Electrical property analysis revealed a higher electrical insulation of photocured nanocomposite resin film at 3.20 x 1012 9 in comparison with that of oligomer film at 1.18 x 10(12) Omega at 6.15 V to drive the bare OLED. This resulted a lower leakage current and the device driving voltage was efficiently reduced so that the nanocomposite-encapsulated OLED could be driven at a lower driving voltage of 6.09 V rather than 6.77 V for the oligomer-encapsulated OLED at the current density of 20 mA/cm(2). Luminance measurement revealed a less than 1.0% luminance difference of OLEDs encapsulated by various types of resins, which indicates that the photo-polymerization takes very little effect on the light-emitting property of OLEDs. Lifetime measurement of OLEDs found that t(80), the time span for the normalized luminance of device drops to 80%, for nanocomposite-encapsulated OLED is 350.17 h in contrast to 16.83 h for bare OLED and 178.17 h for the oligomer-encapsulated OLED. This demonstrates that nanocomposite resin with optimum properties is feasible to OLED packaging and a compact device structure could be achieved via the method of direct encapsulation.