Productivity-Improvement Strategy for TFT-LCD Manufacturing
Patterning of a-Si:H by Laser Printing
Line Open and Short Defect Classification Methodology for AMLCD Array Test Using Voltage Imaging
Dry-Etching Characteristics of PE-CVD SiN Film
The Effect of Dry-Etching upon AMLCD Substrate Glasses
Dry-Etching of Indium Tin Oxide for Flat-Panel-Display
Thermal Shrinkage and Chemical Durability of NA35 Glass Substrate for AMLCD Applications
Acrylic Topcoat Optimization via Dynamic Mechanical Analysis
Environmentally Safe Production of Black Matrices for LCDs
Lithographic Performance of Cationic Color-Filter Photoresists
Flat-Panel-Display Development Activities at Sandia National Laboratories
Small Thermal Compaction of Annealed Soda-Lime-Silicate Glass Substrate of AMLCDs
A New Method for Accurate Overlay in Lithography of Flat-Panel Displays
Measurements of Fusion and Float-Glass Plate Flatness Using a Fizeau Interferometer
Pigment-Dispersed Organic Black-Matrix Photoresists for LCD Color Filters
Productivity-Improvement
Strategy for TFT-LCD Manufacturing
Z. Tajima
Hitachi, Ltd., Tokyo, Japan
full paper
The increasing AMLCD market for PC applications requires cost reduction and performance imporvement in TFT-LCDs. Productivity improvement is the dominant factor for cost reduction. Our strategy for productivity improvements in TFT-LCDs is reviewed.
Patterning of a-Si:H by Laser Printing
D. Shen
University of Alabama, Huntsville, AL
H. Gleskkova,
S. Wagner
Princeton University, Princeton, NJ
full paper
The results of experiments on laser printing of etch masks and metalization of a-Si:H and a-Si,N:H films and glass substrates is reported. The high resolution (1800 dpi) of commercial laser printers is rapidly approaching the design rules for the active matrices of LCDs. Xerographic toner is used as an etch mask for amorphous silicon a-Si:H and for the seeding of metal lines. We also demonstrate for the first time the direct-print patterning of silicon on flexible glass foil.
Line Open and Short Defect
Classification Methodology for AMLCD Array Test Using Voltage Imaging
Y. M. Liu, M. Miller, F. Henley
Photon Dynamics, INC., Mipitas,
CA
M. Nguyen, J. Levine, H. Steemers
Xerox PARC, Palo Alto, CA full paper
A methodology using Voltage Imaging [TM] to detect and classify line open and short defects in an active-matrix array was developed and analyzed. The analysis shows that distinctive voltage patterns exist for the five line-defect types, allowing for detection and classification through the voltage-measurement system.
Voltage Imaging is a trademark of Photon Dynamics
Dry-Etching Characteristics of PE-CVD SiN Film
S.
Saito, N. Makino, J. Tonotani, Y. Kataoka
Toshiba Corp., Kanagawa,
Japan full paper
Dry etching characteristics of plasma enhanced chemical vapor deposited (PE-CVD) SiN film have been investigated using down flow etching for TFT-LCD manufacturing. The etching rate was much faster than that of thermal-CVD SiN. It was considered that hydrogen included in PE-CVD SiN film assists removal of nitrogen which obstructed the reaction of Si atoms with etching species
The
Effect of Dry-Etching upon AMLCD Substrate Glasses
S.
Sarhangi, P.L. Bocko, N. J. Visovsky
Corning Incorporated, Corning,
NY full paper
A study that quantifies the texture and chemical changes on various AMLCD glass substrates during during exposure to chlorine and fluorine based dry etch processes. Chlorine-based etching has less effect upon glass surface than fluorine. Code 1737 glass showed the least surface damage of tested glasses during fluorine over-etch conditions.
Dry-Etching of Indium Tin Oxide for
Flat-Panel-Display Fabrication
C. Barratt, C.
Constantine, D. Johnson
Plasma-Therm, In., St. Petersburg
W.
Barrow
Planar Systems, Beaverton, OR full
paper
The patterning of thin films of ITO is required for the fabrication of most of the major FPD technologies, This paper describes a large area reactive ion etching technology that provides etch rates of 750A/min of ITO. This technology is capable of providing useful selectivities over a photoresist mask as well as stop layers such as aluminium and amorphous silicon. The use of 27.12 MHz can provide a fifty percent reduction in the induced bias voltage present during processing with no reduction in the etch performance.
Dry Laser-Assisted Cleaning
Process as an Alternative to Wet-Chemical Cleaning for Flat-Panel
Display Manufacturing
A. C. Engelsberg
Radiance Services Co., Bethesda full paper
Cleaning represents a capital and operational cost center as well as a yield lever. A cleaning process which uses deep UV photons in combination with a flowing inert gas is an environmentally friendly and economical alternative. Experiments have indicated there is no stress to the substrate or changes in the thin-film integrity.
Thermal
Shrinkage and Chemical Durability of NA35 Glass Substrate for AMLCD
Applications
J. Makino, M. Goto
NH Techno Glass
Corp., Yokkaichi-shi, Japan
T. Shoki
Hoya Corp., Tokyo, Japan full paper
Thermal shrinkage and chemical durability of as-drawn NA35 glass developed for AMLCD applications, which has high strain point of 650 degrees Celsius and low specific gravity of 2.50 g/cubic centimeters, were investigated in detail. NA35 substrate has low thermal shrinkage of 5 ppm which is uniform over the large glass area at a-Si processing temperatures (400 C) with out a preliminary annealing. The NA35 glass was found to have acceptable excellent chemical durability for a-Si TFT processing .
Barrier Layers for LCD Glass
F. P. Fehlner, K. R.
Salisbury, N. J. Binkowski
Corning Incorporated, Corning, NY full paper
Barrier layers have been used in both solid state electronics and liquid crystal displays (LCDs) to localize mobile ions such as sodium. In the case of passive matrix LCDs, silica layers are utilized to prevent the hydrogen for sodium exchange which degrades performance over time. Barriers to sodium for active matrix LCDs prevent contamination of thin film transistors during fabrication from components of the glass such as sodium, boron, and aluminum. In the present work, the movement of sodium between Code 7059 glass and barrier layers of silica or alumina has been measured using SIMS. Findings indicate that sodium moves in the opposite direction for silica and alumina films.
Acrylic Topcoat
Optimization via Dynamic Mechanical Analysis
E. Pavelchek, M. doCanto, M. E. Perkins, R. L. Brainard
Shipley
Co., Marlboro, MA full paper
An acrylic topcoat for use in color filter plate manufacture has been formulated with high clarity and very good shelf life in a one bottle product. The mechanical properties of the formulations were measured by dynamic mechanical analysis to optimize wrinkling resistance during the anneal of superposed ITO layers. The glass transition temperature was raised to over 190 degrees Celsius, allowing anneals over 220 degrees Celsius.
Environmentally Safe
Production of Black Matrices for LCDs
G. Cernigliaro
Shipley
Co., Marlboro, MA
C. P. Esposito, T. Kobayashi, N. Nagoya, M.
Yashiro, H. Yoshikawa
Shipley Far East Ltd., Niigata, Japan full paper
There are concerns about the environmental impact of chromic ion waste generated during the manufacture of Black Matrix for LCD's. Substitution of an electroless nickel plating process on a reduced ITO surface for chrome sputtering has reduced this problem. This method gives very good adhesion and excellent reflectivity at comparable manufacturing costs to black chrome.
Lithographic Performance of Cationic Color-Filter Photoresists
R. L. Brainard, M. E. Perkins, L. F. Bacchetti, M. doCanto, E. K.
Pavelchek, G. J. Cernigliaro
Shipley Co., Marlboro, MA
E. S. Simon
Rohm and Haas Co., Spring House, PA full paper
Red-, green-, and blue-pigmented photoresists, based on a negative-working, cationically initiated, photopolymer system, have been designed. The effect of soft-bake, exposure, post-exposure bake, and development processes on print-dose photospeed, resolution, post-imaging surface residues, and edge profile for imaged color filter arrays are described.
Flat-Panel-Display
Development Activities at Sandia National Laboratories
E.
G. DiBello, W. Worobey, S. N. Burchett, W. A. Hareland, T. E. Felter, R.
Mays, R. T. McGrath
Sandia National Laboratories, Albuquerque, NM full paper
The flat panel display development activities underway at Sandia National Laboratories are described. Research is being conducted in the areas of glass substrates, plasma display modeling, phosphors, electron emissions, and large area manufacturing processes. Projects are focused on improving process yield, developing large area processes, and using modeling techniques to predict design performance.
Small Thermal
Compaction of Annealed Soda-Lime-Silicate Glass Substrate for AMLCDs
T. Itoh, I. Yamaguchi, C. Sakai, K. Katoh
NSG Techno-Research
Co., Ltd., Hyogo, Japan
K. Kiyohara
NSG Fine Glass Co., Ltd.,
Kanagawa, Japan full paper
Based upon the analysis of the structural relaxation model, the thermal compaction of the Soda-Lime Silicate glass substrate has been studied. Experimental results indicated that the compaction after a 400 C - 1 hour process could be minimized less than 10ppm if the glass were pre-annealed at the certain thermal history. The compaction of glass substrates pre-annealed at 500 C - 1 hour, 470 C - 3 hour, and 450 C - 6 hour were 9.2ppm, 6.8ppm, and 8.4ppm, respectively.
A New Method for Accurate Overlay in Lithography of Flat-Panel Displays
B. H. Khalaj, Y. C. Pati, T. Kailath
Stanford University,
Stanford, CA full paper
A new method to ensure accurate overlay in lithography of large substrates and high-density quasi-periodic patterns, such as flat panel displays (FPDs), while avoiding time-consuming (e.g. site-by-site) alignment procedures is discussed. A new signal processing technique estimates and compensates for substrate distortion and thereby permitting the use of time-efficient alignment procedures (e.g. global alignment) without compromising overlay accuracy.
Measurements
of Fusion and Float-Glass Plate Flatness Using a Fizeau Interferometer
R. C. Sumner
MRS Technology, Inc., Chelmsford, MA full paper
The effective flatness of glass plates which are vacuum-chucked to a stage is important to stepper imaging. A measurement technique which utilizes a Fizeau interferometer was used to record the thickness variation of fusion and float glass samples. Measurements of both fusion and float glass thickness variations tended to have a one-dimensional spatial frequency component, or ripple, with a consistent orientation throughout the plate. Fusion glass samples from 2 different manufacturers had 0.3 to 4.0µm of thickness variation.
Pigment-Dispersed Organic Black-Matrix
Photoresists for LCD Color Filters
C. M. Hesler, E. S.
Simon
Rohm and Haas Co., Spring House, PA
L. Bacchetti, R. Brainard
Shipley Co., Marlboro, MA full
paper
Red, green, and blue pigmented photoresists based on a negative-working, cationically-initiated photopolymer system are considered for use as pigmented photoresists in the production of large area LCD color filter plates. A complementary prototype photoresist system, using dispersed organic pigments, intended for the construction of the organic black matrix is also reviewed. Appropriate dispersants and pigments were formulated to develop a material with low conductivity and low transmission suitable for application by spin-coating.