Browsing by Author "Whang, WT"

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2,8-Bis(3-phenylquinoxalin-2-yl)-5 lambda(6)-dibenzo[b,d] thiophene-5,5-dione
(2005-12-01)
Huang, TH
;
Whang, WT
;
Wen, YS
;
Lin, JT
;
材料科學與工程學系
The bond lengths and angles in the title compound, C40H24N4O2S, are normal. The dihedral angles between the dibenzothiophene-S,S-dioxide and two quinoxaline groups are 34.88 (1) and 45.86 (1)degrees.
2-phenyl-3-[6-(3-phenylquinoxalin-2-yl)-dibenzo[b,d]thiophen-3-yl]quinoxaline
(2005-12-01)
Huang, TH
;
Whang, WT
;
Wen, YS
;
Lin, JT
;
材料科學與工程學系
In the molecule of the title compound, C40H24N4S, the two benzene rings fused to the thiophene ring form a dihedral angle of 2.3 (2)degrees. In the crystal structure, there are no significant hydrogen-bonding interactions, but there are pi - pi stacking interactions between molecules.
A novel low-temperature growth and characterization of single crystal ZnO nanorods
(2003-12-20)
Hung, CH
;
Whang, WT
;
材料科學與工程學系
;
Department of Materials Science and Engineering
One-dimensional (1D) single crystal ZnO nanorods directly grown on ZnO nanostructured substrates by soft chemical method is proposed. Employing a novel two steps procedure, the ZnO nanorods with a diameter about 45 nm can be successfully grown on substrate in aqueous solution at attractive low temperature in 90 degreesC, permitting large-scale fabrication with a relatively low cost and a potential application in optoelectronic nanodevices. The structures, appearances and optical properties of ZnO nanorods also have been characterized. (C) 2003 Elsevier B.V. All rights reserved.
A study of the relationship between the electroluminescence characteristics and compositions of PPV-PVA-based polymers
(1996-08-01)
Chang, WP
;
Whang, WT
;
材料科學與工程學系
;
Department of Materials Science and Engineering
A series of poly(p-phenylene vinylene) (PPV)-poly(vinyl alcohol) (PVA)-based polymers were prepared from the PPV precursor and PVA aqueous solution mixtures. The luminescence characteristics of the PPV-PVA-based polymers were dependent on their composition and the following treating conditions. The emitted light of the PPV-PVA-based light-emitting diodes (LEDs) shifted from yellow-green (550 nm) to blue (485 nm) as the PVA component increased. The infra-red (i.r.) absorption spectra showed that some part of the PPV precursor could react with PVA to form C-O-C linkages and interrupted the conjugation of PPV polymer chains. This resulted in decrease of the conjugated chain length, as evidenced in ultraviolet-visible u.v.-vis. absorption spectra. The relative photoluminescence (PL) intensity increases with decreasing the conjugated chain length. The relative electroluminescence (EL) decreases with the increase of the PVA component in the polymers. However, both PL and EL intensity normalized with PPV molar ratio of PPV-PVA-based polymers were higher than that of pure PPV. The relative low threshold voltage at 4-6 V was found in these PPV-PVA-based polymer LEDs with Al (negative) and indium-tin oxide ITO (positive) as the two electrodes. Copyright (C) 1996 Elsevier Science Ltd.
A study of the relationship between the electroluminescence characteristics and compositions of PPV-PVA-based polymers
(1996-08-01)
Chang, WP
;
Whang, WT
;
材料科學與工程學系
;
Department of Materials Science and Engineering
A series of poly(p-phenylene vinylene) (PPV)-poly(vinyl alcohol) (PVA)-based polymers were prepared from the PPV precursor and PVA aqueous solution mixtures. The luminescence characteristics of the PPV-PVA-based polymers were dependent on their composition and the following treating conditions. The emitted light of the PPV-PVA-based light-emitting diodes (LEDs) shifted from yellow-green (550 nm) to blue (485 nm) as the PVA component increased. The infra-red (i.r.) absorption spectra showed that some part of the PPV precursor could react with PVA to form C-O-C linkages and interrupted the conjugation of PPV polymer chains. This resulted in decrease of the conjugated chain length, as evidenced in ultraviolet-visible u.v.-vis. absorption spectra. The relative photoluminescence (PL) intensity increases with decreasing the conjugated chain length. The relative electroluminescence (EL) decreases with the increase of the PVA component in the polymers. However, both PL and EL intensity normalized with PPV molar ratio of PPV-PVA-based polymers were higher than that of pure PPV. The relative low threshold voltage at 4-6 V was found in these PPV-PVA-based polymer LEDs with Al (negative) and indium-tin oxide ITO (positive) as the two electrodes. Copyright (C) 1996 Elsevier Science Ltd.
Analyses on physical mechanism of holographic recording in phenanthrenequinone-doped poly(methyl methacrylate) hybrid materials
(2004-09-01)
Hsiao, YN
;
Whang, WT
;
Lin, SH
;
材料科學與工程學系
;
電子物理學系
The photoproducts in phenanthrenequinone (PQ)-dissolved methyl methacrylate (MMA) liquid samples and PQ-doped poly(methyl methacrylate) (PQ/PMMA) solid photopolymer samples have been analyzed by various chemical measurements. A mechanism for holographic recording in our PQ/PMMA photopolymer is proposed. By UV-VIS transmission and photoluminescence spectral measurements, we find that under light exposure the molecular structure of PQ is transformed to be less conjugated. The measured results of mass spectra, Fourier transform infrared spectra, NMR spectra, and gel permeation chromatograph of analyses provide some evidence for recognizing the molecular structure of the photoproducts in our PQ/PMMA photopolymers. The results show that under light exposure the PQ and MMA form new molecules, mainly an adduct of one PQ molecule with one MMA molecule. In addition, PQ also reacts as a photoinitiator to form PMMA oligomers in our samples. The structure change of the PQ molecule induces a strong change of the refractive index in the material. It provides a mechanism to record a phase hologram in our PQ/PMMA photopolymer. Holographic recordings in the samples are demonstrated, and the dynamic range of the sample is investigated. (C) 2004 Society of Photo-Optical Instrumentation Engineers.
Characteristics of an electropolymerized PPV and its light-emitting diode
(1996-04-01)
Chang, WP
;
Whang, WT
;
Lin, PW
;
材料科學與工程學系
;
Department of Materials Science and Engineering
Poly(phenylene vinylene) (PPV) has been prepared successfully from p-xylylenebis(triphenylphosphonium bromide) in acetonitrile solution via an electroreduction polymerization. p-Xylylenebis(triphenylphosphonium bromide) also acted as an electrolyte in the solution. The resultant electropolymerized PPV film was transparent and dense, and had considerable adhesion to an indium-tin oxide (ITO) electrode. The electropolymerized PPV showed a blue shift both in the ultraviolet-visible absorption spectrum and photoluminescence, compared with the PPV prepared from a p-xylylenebis(tetrahydrothiophenium chloride) precursor route, indicating that it has a shorter pi-conjugated chain length. The infra-red absorption spectra showed a stable P-C bond on the electropolymerized PPV chain. The Al/electropolymerized PPV/ITO light-emitting diode emitted green light with an emission maximum at 530 nm. Annealing the electroluminescence device in a high vacuum oven at 160 degrees C for 3 h significantly enhanced the electroluminescence performance as a result of improvement of the interfacial contact between PPV and the Al metal electrode. Copyright (C) 1996 Elsevier Science Ltd.
Characterization of hydrogen-treated pentacene organic thin film transistors
(2004-04-01)
Yang, JY
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Suen, SC
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Whang, WT
;
材料科學與工程學系
;
Department of Materials Science and Engineering
The electrical characteristics of hydrogen-postannealed and hydrogen-plasma-treated pentacene thin film transistors (TFTs) have been investigated. Experimental results have shown that the hydrogen-treated TFTs have improved field-effect mobility and a higher current on/off ratio, compared to untreated devices. The on/off current ratio of the hydrogen-treated devices was markedly increased. However, the TFTs treated with hydrogen plasma have degraded field-effect mobility, compared to hydrogen-postannealed devices.
Comparison of the recording dynamics of phenanthrenequinone-doped poly(methyl methacrplate) materials
(2001-07-01)
Mumbru, J
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Solomatine, I
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Psaltis, D
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Lin, SH
;
Hsu, KY
A comparative analysis of phenanthrenequinone-doped poly(methyl methacrylate) materials fabricated at California Institute of Technology and National Chiao Tung University is performed in order to understand the differences exhibited in their recording and baking dynamics. (C) 2001 Published by Elsevier Science B.V.
Dynamic mechanical properties of polyimide/poly(silsesquioxane)-like hybrid films
(2001-09-06)
Tsai, MH
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Whang, WT
;
材料科學與工程學系
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Department of Materials Science and Engineering
Polyimide/poly(silsesquioxane)-like (PI/PSSQ-like) films have three-dimensional structure with linear PI blocks and a crosslinked PSSQ-like structure. They have higher thermal stability and char yields than pure PI from 4,4'-diaminodiphenyl ether and 3, 3'-oxydiphthalic anhydride (ODPA). In a series of X-PIS [PI modified with p-aminophenyltrimethoxysilane (APTS), where X is the molecular weight of each PI block] hybrid films, decreasing the PI block chain length enhances the storage modulus, tensile modulus, and glass-transition temperature (T-g) but reduces the alpha -relaxation damping peak intensity, density, and elongation. The change in the former three properties may be caused by an increase in the crosslinking density and rigidity of the network structure. The changes in the next two properties are caused by an increase in the free volume or the PI interblock separation and decreases in the interblock PI chain interaction. The change in the last property (i.e., a decrease in elongation) is related to the increase in the rigidity of the network structure. The activation energy of the a transition depends on the chain length of the PI block. A maximum value is reached at the chain length of 10,000 because of two different factors: crosslinking density and free volume. In a series of X-PIS-y-PTS [X-PIS modified with phenyltrimethoxysilane (PTS), where y is the weight-ratio percentage of PTS to APTS-polyamic acid] films with a constant PI block length, the storage modulus, tensile modulus, T-g, density, and alpha -relaxation damping peak intensity decrease with the PTS content. This could be because of the increase of the PSSQ-like domain size with the PTS content, which leads to the introduction of more free volume or interblock separation and to a decrease in the interblock chain interaction force. (C) 2001 John Wiley & Sons, Inc.
Effect of side chain alkyl length on the electroluminescence characteristics of carbazole-based light emitting polymers
(2001-09-28)
Chao, CS
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Whang, WT
;
Hung, CH
;
材料科學與工程學系
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Department of Materials Science and Engineering
Three carbazole-based copolymers with different long side chains were synthesized using the Wittig reaction. These three copolymers and model compound were characterized by nuclear magnetic resonance (NMR) spectroscopy to determine the cis/trans ratio. The cis/ trans ratios decrease with the side chain length due to the variation in the degree of steric hindrance in the Wittig reaction. They affect the electroluminescence (EL) characteristics of the carbazole-based light emitting polymers. As the length of the side chain increases the wavelength of the emitted light increases proportionally whereas a decrease in the threshold voltages, 5.2, 4.8, 2.5 V was observed. However, EL intensity at same applied voltage creases with the length of the side chain. The energy levels of these three copolymers were also investigated to account for the phenomenon.
Effect of surface stabilization of nanoparticles on luminescent characteristics in ZnO/poly(hydroxyethyl methacrylate) nanohybrid films
(2005-01-14)
Hung, CH
;
Whang, WT
;
材料科學與工程學系
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Department of Materials Science and Engineering
Highly transparent and stable luminescent ZnO/poly(hydroxyethyl methacrylate) nanocomposites have been synthesized via a nanoparticle surface modified method. 3-(Trimethoxysilyl)propyl methacrylate (TPM) was used as the stabilizing agent in a simple, mild sol-gel route to prepare TPM-modified ZnO nanoparticles. The existence of TPM on the nanoparticle surface effectively promotes the stability of colloidal ZnO nanoparticles and the compatibility between the inorganic nanoparticles and the organic matrix in the solid nanohybrid. The resulting ZnO/PHEMA nanocomposites with TPM-modified nanoparticles have better dispersibility and controllable luminescent properties. The characteristics of TPM-modified and unmodified ZnO nanoparticles have been studied by ultraviolet-visible (UV-vis) absorption spectroscopy, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and (1)H NMR spectroscopy.
Effect of the polyimide structure and ZnO concentration on the morphology and characteristics of polyimide/ZnO nanohybrid films
(2005-01-21)
Hsu, SC
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Whang, WT
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Hung, CH
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Chiang, PC
;
Hsiao, KN
A series of polyimide/ZnO nanohybrid films with different ZnO content were prepared from a rigid pyromellitic dianhydride-4,4'-diaminodiphenyl ether (PMDA-ODA) polyimide (PI) and a flexible 3,3,4,4-benzophenonetetracarboxylic acid dianhydride-4,4'-diaminodiphenyl ether (BTDA-ODA) PI with ZnO nanoparticles (3-4 nm). Fourier-transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) depict that the ZnO nanoparticles function as a physical cross-linking agent with PI through hydrogen bonding between the OH on the ZnO nanoparticles and the C=O of the imide groups. ZnO nanoparticles in the rigid PMDA-ODA matrix cause a larger percentage decrease in the coefficient of linear thermal expansion (CTE) than in the flexible BTDA-ODA matrix. The BTDA-ODA/ZnO hybrid films have two transition peaks in dynamic mechanical tan curves, but PMDA-ODA/ZnO hybrid films only have one transition peak. Thermogravimetric analysis reveals that ZnO decreases the thermal degradation temperature (T-d) in both hybrid films, but less so in PMDA-ODA/ZnO films. Trans-mission electron microscopy (TEM) images reveal that the rigid matrix induces larger particle size (30-40 nm) compared to the flexible matrix (10-15 nm).
Effect of the sensitizer on the properties of fully functionalized photorefractive epoxy polymers and their performance in the hologram image storage
(1999-06-01)
Chang, CJ
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Whang, WT
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Hsu, KY
;
Hsieh, ML
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材料科學與工程學系
The 3-amino-9-ethyl carbazole (AEC)/Dispersed Orange 3 (DO3)/diglycidyl 1,2 cyclohexanedicarboxylate (DCD) main chain copolymers are synthesized and studied on their photorefractive (PR), photoconductive, and holographic characteristics. They are good hologram recording media because not only the stored hologram exhibits excellent fringe contrast with the resolution at about 20 mu m, but also the image can be stored, erased, and overwritten. The UV/Vis spectra shows that AEC segments may form charge transfer complexes with either DO3 segments or TNF sensitizers. By incorporating the sensitizer or increasing the charge transfer component concentration, the grating growth rate can be speeded up. Applying an electric field on the polymer film containing no sensitizer helps to elevate the grating growth speed, but it shows little influence on the grating growth speed of the films with sensitizers. More nonlinear optical (NLO) segments in the copolymer result in higher diffraction efficiency. The dark decay of the film depends on the dark conductivity. Incorporating sensitizers or more charge transport segments leads to more dark decay because of increasing dark conductivity. The dark decay of the PR properties at elevated temperature can also be evaluated by the thermal stimulated discharge current (TSDC) spectroscopy technique. (C) 1999 John Wiley & Sons, Inc.
Effect of ZnMA on optical and holographic characteristics of doped PQ/PMMA photopolymer
(2005-02-01)
Hsiao, YN
;
Whang, WT
;
Lin, SH
;
材料科學與工程學系
;
電子物理學系
We report on the fabrication and experimental characteristics of doping Zinc methylacrylate (ZnMA) and 9,10-phenanthrenequinone (PQ) into a poly(methyl methacrylate) (PMMA) photopolymer. The effects of a ZnMA dopant on the optical and holographic characteristics of ZnMA/PQ/PMMA have been examined. From the optical and holographic measurements of different samples with different composition ratios, we found that the time to reach the maximum diffraction efficiency has been reduced from 102 to 59 (reduced by 1.7 times) and the diffraction efficiency has been raised up from 0.57 to 1.62% (increased by 2.9 times). We also found that holographic gratings can be recorded in pure PQ-doped PMMA, but cannot be recorded in pure ZnMA-doped PMMA. The higher the concentration of PQ in codoped PMMA, the higher the diffraction efficiency. In contrast, the higher ZnMA concentration in the codoped PMMA, the shorter the response time. It is proposed that PQ serves as a photosensitive reactant and plays a major role in the formation of phase gratings. ZnMA serves as a sufficient catalyst to accelerate the reaction of PQ with a polymer or ZnMA. By adding ZnMA with a proper concentration into a PQ/PMMA photopolymer, we succeeded in improving the holographic characteristic of the photopolymer.
Effects of morphology and surface characteristics of poly(imide siloxane)s and deep UV/O-3 surface treatment on the interfacial adhesion of poly(imide siloxane)/alloy-42 leadframe joints
(1999-07-01)
Jwo, SL
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Whang, WT
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Hsieh, TE
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Pan, FM
;
Liaw, WC
The effect of surface characteristics and morphology of poly(imide siloxane) (PIS) on the true interfacial adhesion between PIS films and alloy-42 substrates was studied. The effect of the viscosity of PIS films and the surface treatment of deep UV/O-3 (d-UV/O-3) on alloy-42 plates on the peel strength of PIS films/alloy-42 joints has also investigated. 3,3',4,4'-benzophenone tetracarboxylic dianhydride/2,2'-bis[4-(3-aminophenoxy)phenyl]sulfone (BTDA/m-BAPS) based PIS films with alpha,omega-bis(3-aminopropyl)polydimethyl siloxane (APPS) molecular weight M-n = 996 g/mole (PIS9Siy) show two phases in all compositions and the linear dependence of the critical surface tension on the surface concentration of the silicon, [Si-surf], on the PIS films. The PIS films with the APPS M-n = 507 g/mole (PIS5Siy) or M-n = 715 g/mole (PIS7Siy) exhibit a morphology change from a homogeneous phase to an inhomogeneous phase starting at the mole ratio (y) of APPS/PIS = 2.7% and 1.1%, respectively. The curves of critical surface tension dependence on the [Si-surf] discontinue or deflect at these two compositions, respectively. The treatment of d-UV/O-3 on alloy-42 plates improves the wetting on the alloy surface and promotes the peel strength between the PIS films and alloy-42 plates by a magnitude of greater than or equal to 20%. These results show that the flowability of the same PIS films bonding at different temperatures significantly affects the bonding strength of the joints, but the flowability of different PIS films bonding at the same temperature, e.g. 400 degrees C, is not the key factor governing the bonding strength of the joints. The true interfacial adhesion of the PIS5Si0.6/alloy-42 joint is 80% higher than that of the unmodified BTDA/m-BAPS based polyimide film/alloy-42 joint. However, zero true interfacial adhesion is obtained between the PIS9Siy films and alloy-42 plates. The wetting kinetics experiment shows that the higher the siloxane content in the PIS, the higher the activation energy for the adhesive bonding process. Moreover, the phase sepration significantly increases the activation energy. The scanning electron micrographs of the peeled-off PIS film surfaces from the PIS/alloy-42 joints reveal the rougher surface morphology from the sample with the higher interfacial adhesion.
Effects of the solubility parameter of polyimides and the segment length of siloxane block on the morphology and properties of poly(imide siloxane)
(1999-12-13)
Jwo, SL
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Whang, WT
;
Liaw, WC
;
材料科學與工程學系
;
Department of Materials Science and Engineering
The dependence of morphology of the poly(imide siloxane)s (PISs) on the solubility parameter of unmodified polyimides and the molecular weight and content of alpha,omega-bis(3-aminopropyl) polydimethylsiloxane (APPS) has been studied. The effect of the morphology on the mechanical properties is also under investigation. The domain formation in the PISs with the APPS molecular weight M-n = 507 g/mol is not found until the mol ratio of APPS/PIS greater than or equal to 0.5% in the pyromellitic dianhydride/p-phenylene diamine (PMDA/p-PDA)-based PISs, and at a mol ratio greater than or equal to 2.7% in the 3,3',4,4'-benzophenone tetracarboxylic dianhydride/2,2'-bis[4-(3-aminophenoxy)phenyl] sulfone (BTDA/m-BAPS)-based PISs. As the APPS M-n = 715 g/mol, the critical APPS concentrations of the domain formation in both types of PISs are equal to 0.1 and 1.1%, respectively. The critical concentration is equal to 0.6% in the BTDA/m-BAPS-based PIS film with the APPS M-n = 996 g/mol. The isolated siloxane-rich phase in the BTDA/m-BAPS-based PISs becomes a continuous phase as the ,ol ratio of APPS/PIS greater than or equal to 7.7, 10.0, and 16.6% as the APPS M-n = 996, 715, and 507 g/mol, respectively. Dynamic Mechanical Analysis (DMA) shows two T(g)s in the PIS films having phase separation: one at -118 similar to -115 degrees C, being the siloxane-rich phase, the other at 181-244 degrees C, being the aromatic imide-rich phase. The SEM micrographs show a significant deformation on the fractured surfaces of the BTDA/m-BAPS-based PIS films with a continuous siloxane-rich phase. This phenomenon of plastic deformation is also observed in the tensile tests at -118 degrees C and at room temperature. The highest elongation in the PIS films is found at the critical siloxane content of the continuous siloxane-rich phase formation. (C) 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2832-2847, 1999.
Effects of titania content and plasma treatment on the interfacial adhesion mechanism of nano titania-hybridized polyimide and copper system
(2004-06-03)
Chiang, PC
;
Whang, WT
;
Wu, SC
;
Chuang, KR
;
材料科學與工程學系
Nano-titania (TiO2) incorporated into polyimide (PI) matrix can significantly enhance the adhesion strength for PI/TiO2 hybrid film and copper system. Surface modifications by various plasma treatments (Ar, Ar/N-2 and Ar/O-2) were also applied in this study to improve the adhesion strength. The Ar/N2 plasma treatment is regarded as the more effective way in promoting the adhesion strength. The maximum adhesion value of 9.53 N/cm was obtained for the PI/TiO2-1 wt% hybrid film with Ar/N-2 plasma treatment. It is enhanced about 10 times as large as pristine PI. Furthermore, by Ar/O-2 plasma treatment, a weak boundary of copper oxide was formed at the interlayer between PI/TiO2 hybrid film and copper which decreases the adhesion strength. The effects of plasma treatment and content of nanosized TiO2 on the adhesion strength between PI/TiO2 hybrid film and copper system were studied. Atomic force microscope and contact angle analyses were used to measure the changes in surface morphology and surface energy as a result of plasma treatment. Besides, the interfacial states of peeled-off polymer side and copper side were investigated by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Based on the result of XPS spectra, the peeled-off failure mode between PI/TiO2 hybrid film and copper was proposed in this study. (C) 2004 Elsevier Ltd. All rights reserved.
Electroluminescence characteristics of aromatic polyimides by vapor deposition polymerization
(2003)
Hsu, SC
;
Whang, WT
;
Chen, SC
;
材料科學與工程學系
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Department of Materials Science and Engineering
Light emitting polyimide (PI) thin films are successfully prepared from two kinds of diamines: 2,5-Bis(4-aminophenyl)-1,3,4-oxadiazole (BAO) and 4,4'-(9-Fluorenylidene)dianiline (BAPF) reacting with 4,4'-(Hexafluoroisopropylidene)diphthalic anhydride (6FDA) by vapor deposition polymerization (VDP). We succeed to reduce the thickness of the thin polyimide film to 150 Angstrom, and the threshold voltage of BAO-6FDA and BAPF-6FDA PI light-emitting diodes to 4.5 V and 6.5 V respectively. The root mean square of the surface roughness of the BAO-6FDA and BAPF-6FDA PI films are 8.8 Angstrom and 4.7 Angstrom respectively. But that of the BAO-6FDA film from wet coating process is 37.1 Angstrom. Apparently, VDP process is the better way to produce smooth polyimide film. The BAO-6FDA LED film emits a broader electroluminscence (EL) band, covering the full range of visible light (400 nm to 700 nm), than the BAPF-6FDA LED. However, the electroluminescence efficiency of BAPF-6FDA LED device is better than BAO-6FDA LED device. It is due to the better balance on the hole and electron injection in the former and better intermolecular charge transfer.
Experimental characterization of phenanthrenequinone-doped poly(methyl methacrylate) photopolymer for volume holographic storage
(2003-05-01)
Hsu, KY
;
Lin, SH
;
Hsiao, YN
;
Whang, WT
;
材料科學與工程學系
We present an experimental study on the photopolymer poly(methyl methacrylate) doped with phenathrenequinone molecules. Material characteristics for holographic data storage, including optical characteristics, scattering effect, relation between diffraction efficiency and number of holograms, and exposure schedule for multiple storage, are investigated. An experimental demonstration of multiple storage of digital data pages in a polymer cube is presented. (C) 2003 Society of Photo-Optical Instrumentation Engineers.