Thin-Film Phosphors for FED Application
High-Resolution Phosphors: Characterization and Assessment
Improved Performance of Low-Voltage Phosphors for Field-Emission Displays
High-Brightness Blue LEDs Using III-V Nitrides and Their Applications
Design and Manufacturability of Microcavity EL Devices for Display Applications
Improved SrS:Ce, Cl TFEL Devices by ZnS Co-Evaporation
New High-Luminance TFEL Devices Using ZnGa2O4 Phosphor Emitting Layers
Crystalline-As-Deposited CaGa2S4:Ce via Low-Temperature Metal-Organic Chemical Vapor Deposition
Drive for 40-in.-Diagonal Full-Color ac Plasma Display
A High-Resolution 19-in. 1024 x 768 Color ac PDP
A Long-Life dc Color PDP with an Concave Cathode
512(x3) x 256 RGB Multicolor TFEL Display Based on "Color by White"
Laterally Emitting TFEL Display Devices
A 1280 x 1024 Active-Matrix EL Display
An Improved Performance TFEL VGA Gray-Scale Display
Characterization of ZnGa2O4 and YAG:CR Phosphors for Field-Emission Displays
Liquid-Phase Electroluminescent Displays
Phosphor Field Dependence in ALE-Grown SrS:Ce ACTFEL Devices
Modeling Space Charge in ACTFEL Devices Using a Single-Sheet-Charge Model
Brighter Blue CaxSr1-xGa2S3:Ce EL Devices with an Electron Injection Layer
A Thick/Thin-Film ac Hybrid EL Display for Use in Monochrome and Full-Color Applications
Thick-Film Materials for Plasma Displays
Optimization of a Mew DCPDP Cell Structure
Plasma Chemistry and Modeling of Rare-Gas/Xenon Plasma Display Cell
Preparation of Copper, Aluminum,
Gold-Activated Zinc Sulfide with Optimum Cathodoluminescence for
Entertainment Color Television
R. G. W. Gingerich, A. F.
Kasenga
Osram Sylvania, Inc., Towanda, PA
full paper
A viewing screen in a color CRT is comprised of an array of blue, green, and red fluorescent materials which are arranged in a pattern. Recently, copper, aluminum-activated zinc, cadmium sulfide has been replaced by copper, aluminum-activated zinc sulfide and/or copper, gold, aluminum-activated zinc sulfide for environmental reasons. Preparation of copper, gold, aluminum-activated zinc sulfide with optimum cathodoluminescent light output is discussed with respect to eight synthetic parameters.
Thin-Film Phosphors for FED Application
D. W. Smith, A.
Vecht, C. S. Gibbons
University of Greenwich, London, U.K.
D.
Morton, C. Walding
Army Research Laboratory, Ft. Monmouth, NJ full paper
Thin films prepared by organometalic aerosol
spray pyrolysis technology showing promising low voltage properties are
described. Phosphor films based on the ZnO:Zn, ZnGa2O4:Mn, SnO4:Eu,
Y2O3:Eu and Y3Al5O12:Tb systems were prepared and analyzed. Their
luminance characteristics, spectral emission distribution and other data
are presented. Over 200 fL was achieved at 1500V.
Key Words: Thin
films, low voltage, FED phosphors, aerosol spray pyrolysis.
High-Resolution Phosphors:
Characterization and Assessment
H. Tanner, A Vecht, D.
W. Smith, C. S. Gibbons, D. Charlesworth
University of Greenwich,
London, U. K. full paper
Detailed
analysis of novel methods of preparation of powder phosphors for high
resolution application are presented. Phosphor systems showing high
efficiency with mean particle sizes in the range 2-3 microns are
described. The utilization of Coulter Counter measurements is assessed.
Key words: High resolution, particle size, Coulter counter, powder
phosphors.
Electron-Stimulated
Surface Reactions between Residual Vacuum Gas and ZnS
Field-Emission-Display Phosphors
J. Sebastian, S. Jones,
T. Trottier, H. Swart, P. Holloway
University of Florida,
Gainesville, FL full paper
Films of ZnS on Si (100) have been subject to electron bombardment (0.5-5 KeV) over a range of pressures from 10E-6 to 10E-9 Torr. Various gases including hydrogen and oxygen were introduced into the ambient during bombardment, in order to assess their effect on surface modification. Auger electron spectroscopy data indicate that in the presence of oxygen and hydrogen, sulfur was depleted from the surface during electron bombardment. The most likely mechanism for this action seems to be the electron beam dissociation of molecular species to atomic hydrogen and oxygen followed by a surface reaction forming high vapor pressure sulfur compounds (e. g. SOx and H2S). The consequences of these reactions on the use of ZnS phosphors in field-emission flat-panel displays is discussed
Improved
Performance of Low-Voltage Phosphors for Field-Emission Displays
S. M. Jacobsen, S. Yang, F.-L. Zhang, C. J. Summers
Phosphor
Technology Center of Excellence, Georgia Institute of Technology,
Atlanta, GA
C. Bojkov, N. Kumar, L. Fredin, H. Schmidt
SI
Diamond Technology, Inc., Austin, TX full
paper
In this paper improvements in both efficiency and aging of phosphors for low voltage field emission displays are reported. Emphasis is placed on performance in the range 500-1000 volts operation. Aging data will be presented for up to 1000 Coulombs of operation. These new results on improved performance will then be discussed with respect to the choices for FED design architectures.
High-Brightness Blue LEDs Using III-V
Nitrides and Their Applications
S. Nakamura
Nichia
Chemical Industries, Ltd., Tokushima, Japan
full paper
High-brightness InGaN/AlGaN double-heterostructure blue-light-emitting diodes (LEDs) with an external quantum efficiency of 5.4% were fabricated by codoping Zn and Si into an InGaN active layer for full color displays. The output power was as high as 3 mW at a forward current of 20 mA. The peak wavelength and the full width at half-maximum of the electroluminescence of blue LEDs were 450 nm and 70 nm, respectively. Blue-green LEDs with a brightness of 2 cd and a peak wavelength of 500 nm were fabricated for application to traffic lights, by increasing the indium mole fraction of the InGaN active layer.
Design and Manufacturability of
Microcavity EL Devices for Display Applications
L. J.
Rothberg, A. Dodabalapur, T. M. Miller
AT&T Bell Laboratories,
Murray Hill, NJ full paper
Red, green and blue light-emitting diodes are fabricated using a single broadband organic emitter and a resonant cavity design. The manufacturing process is significantly simpler than one requiring pixilation of three emitters for full color displays. There is no attendant loss of brightness relative to a non-cavity device.
Improved SrS:Ce, Cl TFEL Devices by
ZnS Co-Evaporation
R. H. Mauch, D.-O. Velthaus, B. Hüttl,
U. Troppenz, R. Herrman
Heinrich-Hertz Institute, Berlin, Germany full paper
A significant improvement in luminance, efficiency, and stability of SrS:Ce,Cl-based thin film electroluminescent (TFEL) devices has been observed by using ZnS during the SrS:Ce,Cl deposition process. Crystallinity, EL performance and long term reliability have been remarkably improved compared to standard SrS:Ce,Cl. Luminous efficiency levels as high as 1.63 lum/W have been obtained. The excellent crystallinity of the SrS layers has been identified to be responsible for the improved EL performance.
New High-Luminance TFEL Devices
Using ZnGa2O4 Phosphor Emitting Layers
T. Minami, S.
Takata, Y. Kuroi, T. Maeno
Kanazawa Institute of Technology,
Ishikawa, Japan full paper
Newly developed high-luminance thin-film electroluminescent (TFEL) devices use ZnGa2O4 phosphors in conjunction with a thick BaTiO3 ceramic insulator. A luminance as high as 500 cd/sq m and a luminous efficiency of 0.9 lum/W for green emission were obtained in a TFEL device using ZnGa2O4:Mn thin film as the emitting layer when driven by a sinusoidal-wave voltage at 1kHz.
Crystalline-As-Deposited
CaGa2S4:Ce via Low-Temperature Metal-Organic Chemical Vapor Deposition
D. C. Smith, J. A. Samuels, B. F. Espinoza, E. Apen, N. M. Peachey,
R. C. Dye
Los Alamos National Laboratory, Los Alamos, NM
R. T.
Tuenge, C. F. Schaus, C. N. King
Planar Systems, Inc., Beaverton, OR full paper
A metal-organic chemical vapor deposition (MOCVD) process for the growth of crystalline-as-deposited cerium doped calcium thiogallate (CaGa2S4:Ce) at substrate temperatures less than 600°C has been developed. Blue-green electroluminescence was observed with a luminance of ~2 cd/sq. m. at 40 volts above threshold using 60 Hz drive frequency. Threshold voltages were approximately 200 V.
Drive for 40-in.-Diagonal Full-Color ac Plasma
Display
T. Nakamura, K. Iseki, Y. Sano, K. Nunomura
NEC
Corp., Kawasaki, Japan full paper
A surface discharge ac plasma display has been developed, featuring a 40 inch diagonal size and 480x840 color pixels. It features a block priming discharge method, by which each scan electrode block has independent priming discharge timing, shortens the maximum time interval between priming discharge and writing discharge. A base-write pulse reduces self-erasing of the writing discharge, and a sub-write pulse permits using a higher scan pulse voltage without excess writing discharge. These driving techniques make the writing operation stable over a large display area. As a result, non-interlaced mode video picture reproduction with 256 gray levels and 200cd/sq m white area luminance have been achieved.
A High-Resolution 19-in. 1024 x 768 Color ac PDP
H.
Doyeux, J. Deschamps
Thomson Tubes Electroniques, Velizy, France full paper
A 19 inch, 1024 x 768 RGB array, high resolution color ac plasma panel is presented. This display achieves a 0.38-mm color triad pitch while keeping the well-known basic features of PDPs, namely wide viewing angle, image stability, and ruggedness.
High
Luminance and High Luminous Efficiency in Barrier-Electrode Color ac
Plasma Displays Fabricated by Sandblasting Technology
Y.
Kawai, H. Uchiike, T. Takamori, K. Matsuoka, K. Lin, T. Sasaki
Hiroshima
University, Hiroshima, Japan full paper
The application of sandblasting technology to barrier electrode color ac plasma displays resulted in a high area luminance of 570 cd/sq. m. and a high luminous efficiency of 1 lum/W for a cell pitch of 0.5mm.
Discharge Characteristics
of Full-Color Plasma Display Panels with Resistors in Display and
Auxiliary Cells
K. Sasaki, Y. Kobayashi, K. Fujii, A.
Takahashi, H. Sawai
Oki Electric Industry Co., Ltd., Tokyo, Japan full paper
A full-color dc plasma display panel with resistors in each display and auxiliary cell has been fabricated. This panel demonstrates a memory margin exceeding 10 V over a display writing voltage was set from 320 V to 350 V. The voltage range of the auxiliary cell is also significantly wider than for a panel without a resistors in each auxiliary cell.
A Long-Life dc Color PDP with a
Concave Cathode
H. Kono, M. Hirohashi
Matsushita
Research Institute Tokyo, Inc., Kawasaki, Japan
N. Isobe, K. Wani,
K. Takahashi
Matsushita Electronics Research Laboratory, Osaka,
Japan
T. Sakai, J. Koike
NHK Science and Technical Research
Laboratories, Tokyo, Japan full paper
In order to improve the lifetime of a dc color plasma display panel, an experimental panel with gas pressure of 47kPa, 10% Xe content in He-Xe mixture, and the concave cathode structure was fabricated. The pulse-memory dc PDP with concave cathode demonstrated the lifetime of over 30,000 hours.
512(x3) x 256 RGB Multicolor TFEL Display Based on "Color by White"
J. Haaranen, T. Harju, P. Heikkinen, G. Härkönen, M. Leppänen,
T. Lindholm, J. Maula, J. Määttänen, A. Pakkala, E.
Soininen, M. Sonninen, R. Törnqvist, J. Viljanen
Planar
International, Ltd., Espoo, Finland full paper
A 9" diagonal 512(x3).256 RGB TFEL multicolor display based on the broad emission band from a SrS:Ce/ZnS:Mn light emitting film and the inverted TFEL device structure with patterned color filters in the front has been developed. The advantage of this display structure is a simple manufacturing process. A high contrast ratio of 30:1 in a 1000 lux ambient has been achieved with a white areal luminance of 21 cd/sq m. This performance meets the requirements of commercial applications.
Laterally Emitting TFEL
Display Devices
C. B. Thomas, R. Stevens, W. M. Cranton,
I. P. McClean, M. R. Craven, A. H. Abdullah
University of
Bradford, West Yorkshire, U. K. full paper
Both materials and device engineering have been explored to increase the emission from thin film electroluminescent (TFEL) devices. Displays have been fabricated from barrier -layer phosphors created by inserting a tunnelling-layer of Y2O3 within a ZnS:Mn film. The barrier-layer enhances the internal electric field to increase the luminance compared with conventional films and facilitates annealing at 700°C to provide further improvement. Lateral luminances of 200,000fL are obtained at 5kHz compared with less than 90,000fL for a ZnS:Mn layer annealed at 500°C. Surface emission for displays is also complemented by fabricating micro-mirrors around each pixel to reflect, additively, the lateral component. With existing values of the optical attenuation coefficient the optimum pixel geometry is approximately 30sq µm for maximum contribution of lateral emission. Such a value corresponds to a resolution of 66 pixels-per-inch, which is consistent with the requirements for head-mounted displays. Using barrier-layer phosphors and mirrors corresponding to the previous density, lateral emission contributes 1000fL at 10 kHz.
A 1280 x 1024 Active-Matrix EL Display
R. Khormaei, K.
Ping, M. Rhoads, B. Aitchitson, C. N. King
Planar America,
Beaverton, OR
G. Dolny, A. Ipri, F.-L. Hsueh, R. G. Stewart
David Sarnoff Research Center, Princeton, NJ
T. Keyser, G. Becker,
D. Kagey
AlliedSignal Aerospace Corp., Columbia, MD
M. Spitzer
Kopin Corp., Taunton, MA full paper
A 1.3"x 1.1" active matrix electroluminescent (AMEL) display with 1280 columns by 1024 rows is reported with 1000 lines per inch resolution (24µm pitch). This display includes integrated high voltage and storage circuitry at each pixel fabricated on thin-film single crystal silicon-on-insulator (SOI) wafers. Peripheral addressing circuitry has also been incorporated into the display to minimize size and reduce the interconnect complexity. Initial samples were built with a ZnS:Tb green EL phosphor and were evaluated using waveforms typical of intended applications. The results show good optical and electrical performance for use in head-mounted display (HMD) applications. This display demonstrates the successful integration of a solid state light emitting film with active matrix circuitry, formed using conventional SOI processing. This AMEL display shows ideal characteristics for compact high performance head-mounted displays needed for a variety of existing and emerging applications.
An Improved Performance TFEL VGA
Gray-Scale Display
A. Douglas, T. Flegal
Planar
Systems, Inc., Beaverton, OR full paper
An improved performance VGA gray scale thin-film electroluminescent (TFEL) display gas been developed and demonstrated. Sixteen gray levels were obtained, with reduced power and increased brightness compared to previous TFEL gray scale displays. Driver cost was reduced with the use of a new 2-bit column driver. Furthermore, compact packaging was obtained by using chip-on-glass packaging for the row and column drivers.
Characterization
of ZnGa2O4 and YAG:Cr Phosphors for Field-Emission Displays
T. E. Felter, A. A. Talin, M. E. Malinowski
Sandia National
Laboratories, Livermore, CA
A. G. Chakhovskoi
University of
California at Davis, Davis, CA
L. Shea, B. E. Russ, J. McKittrick,
J. Talbot
University of California at San Diego, La Jolla, CA full paper
Two candidate phosphors for application in field emission displays, ZnGa2O4 (blue) and YAG:Cr (red), were excited with electrons from 10,000 tip Spindt-type field emission cathodes. The luminance and chromaticity of each phosphor at 500V anode voltage were measured as a function of anode current and found comparable to those obtained from standard cathode ray tubes. No damage to the FEA cathodes was observed during the measurements. Outgassing was measured with a quadrupole mass spectrometer and the optical emission recorded with a visible light spectrometer.
Liquid-Phase Electroluminescent Displays
P. B. Jaguiro,
A. G. Smirnov
State University of Information and Radioelectronics,
Minsk, Belarus
S. K. Kang
Samsung Display Devices Co., Ltd.,
Suwon, Korea full paper
The current status and prospects of liquid-phase electroluminescent (EL) displays is discussed. Results of investigation of electrolyte-free thin electrochemiluminescent (ECL) cells is presented. A correct physical model explaining the phenomena in such cells and predicting their behavior is described. In this model, cells emit light due to recombination of oppositely charged ion-radicals, which are electrochemically injected from electrodes and are transported by electrohydrodynamic flows. Electro-optical characteristics of segment and matrix ECL displays and their possible applications are discussed
Phosphor Field Dependence in
ALE-Grown SrS:Ce ACTFEL Devices
R. L. Thuemler, P. K.
Keir, J. F. Wager
Oregon State University, Corvallis, OR full paper
Internal charge vs. phosphor field characteristics are measured as a function of phosphor thickness for atomic layer epitaxy (ALE) SrS:Ce devices. Phosphor fields in excess of 3 MV/cm are observed for thin phosphor layers; the phosphor field decreased to about 1 MV/cm for thick phosphor layers. Phosphor field reduction is attributed to an increase in the amount of space charge present in the devices.
Modeling Space Charge in ACTFEL Devices Using a Single-Sheet-Charge
Model
P. D. Keir, W. M. Ang, J. F. Wager
Oregon
State University, Corvallis, OR full paper
Simulation of phosphor space charge in alternating-current thin-film electroluminescent (ACTFEL) devices is performed to determine the effect of space charge on electrical device characteristics. The space charge distribution in the phosphor layer is modeled as a sheet of charge at an arbitrary location in the phosphor layer. Space charge creation is assumed to be caused by either field emission of electrons from bulk traps or impact ionization of deep-level traps in the phosphor layer. Simulation results show that phosphor space charge contributes to anomalous device characteristics such as overshoot in capacitance-voltage (C-V) and internal charge-phosphor field (Q-Fp) measurements.
Brighter
Blue CaxSr1Ga2S3:Ce EL Devices with an Electron Injection Layer
P. D. Rack, P. H. Holloway
University of Florida, Gainesville,
FL
L. Pham and J. Wager
Oregon State University, Corvallis, OR
S.-S. Sun, E. Dickey, C. N. King
Planar Systems, Inc., Beaverton,
OR full paper
Since electroluminescent Ca(x)Sr(1-x)Ga(2)S(4):Ce was first developed, much effort has been devoted to fully understand its potential as a bright blue phosphor. To elucidate its potential, a new electron injection layer has been investigated, the chemical bonding and distribution of cerium have been characterized, and the microstructure of the thin film has been examined.
To increase the brightness of the phosphor, a thin indium electron injection layer has been introduced at the phosphor interface which has reduced the threshold voltage by 15 Volts and increased the brightness 25%. Analysis by Auger electron spectroscopy shows that indium diffuses into the ZnS nucleating layer during heat treatment at 650°C. Capacitance-voltage and charge-phosphor field data showed that the indium increased the injected charge in the TFEL devices.
A
Thick/Thin-Film ac Hybrid EL Display for Use in Monochrome and
Full-Color Applications
P. Bailey, K. Carkner, X. Wu
Westaim
Technologies, Inc., Ft. Sascatchewan, Alberta, Canada full paper
An inverted-stack thick/thin-film ac EL structure incorporating a screen-printed dielectric layer has been developed. Pixel-luminance values in excess of 700 cd/sq m for monochrome and 220 cd/sq m unfiltered white have been achieved a 60Hz and 40V modulation. A bilayer phosphor comprising ZnS:Mn and a multiply doped SrS host layer have achieved 250 cd/sq m with CIE coordinates of 0.41 0.42 under the same driving conditions.
Thick-Film Materials for Plasma Displays
J. J. Felton,
T. Suess, J. Smith, C. Wang
DuPont Electronics Materials, Research
Triangle Park, NC
H. Kanda, M. Tsuchiya
DuPont Electronics
Materials, Yokohama, Japan full paper
A tape-on substrate approach was used to solve the problem of creating an as fired, 150-250 micron layer of sand-blastable dielectric designed for use as a barrier-rib (pixel-wall) material in plasma display panels. Unlike the screen-printing approach to material deposition, which requires 10-15 prints, an adequate thickness can be applied in only two or three layers.
Optimization
of a Mew DCPDP Cell Structure
B. J. Shin, H. S. Jeong,
J. S. Park, K.-W. Whang
Seoul National University, Seoul, Korea
K.
C. Choi
Institute for Advanced Engineering, Seoul, Korea full paper
An improved DCPDP cell structure that is easier to manufacture combines a dc surface discharge with a wall auxiliary anode. Two dimensional computer simulation and experimental results were compared with earlier structures.
Plasma Chemistry and Modeling of Rare-Gas/Xenon Plasma Display Cell
J. W. Shon
Sandia National Laboratories, Livermore, CA
B.
M. Penetrante
Lawrence Livermore National Laboratory, Livermore, CA
R. Veerasingam
The Pennsylvania State University, University
Park, PA
W. L. Morgan
Kinema Research, Monument, CO full paper
A plasma-chemistry model to investigate discharge mechanisms in a rare-gas/xenon plasma display cell was developed. Critical plasma reaction mechanisms and species densities controlling UV production were identified for various gas mixtures. Model results indicate that UV production form XE* is maximum when the electric field strength is approximately 500V/cm.