LARGE AREA ELECTRONICS

TECHNOLOGYTECHNOLOGY

&

APPLICATIONS

APPLICATIONS

Solar Cells

Flat Panel Displays

LEDs

Sensors

Organic/Flexible Electronics

TOPICS

Liquid Crystals

Flat Panel Display Structure Flat Panel Display Structure

Manufacturing Process/Technology and Equipment

LIQUID CRYSTALS

History The 4th State of the Matter

LiquidCrystals may flow like a liquid and may liquid and may crystallize like a solid

MELTING POINTS

145C Liquid Crystal 178C Liquid

LIQUID CRYSTALS

RCA laboratories 1962: Physical Chemist Richard Williams when applied an electric field to a nematic liquid crystal at 125 Cobserved the formation of a regular pattern.

Cobserved the formation of a regular pattern.

Nematic liquid crystal state above 116 C. Impractical in commercial display product.

LIQUID CRYSTALS

RCA laboratories 1966: research chemists J. E. Goldmacher and J. A. Castillano discovered mixtures of nematic compounds with RT nematic Liquid Crystal behaviour.

Nematic liquid crystal state in the range of 22-105 C. Suitable in commercial display product.

THE STRUCTURE OF A FPD/TFT-LCD

The Nematic LCD becomes Twisted Nematic (helical structure) when electrodes are coated with an alignment layer V = 0 the Image becomes TRANSPARENT V 0 the Image becomes OPAQUE

THE STRUCTURE OF A FPD/TFT-LCD

Extra coating: between ITO layers and Alignment layers (hard coating) Purpose: electrical insulation of the surface Material: SiOx Spacers: keep the glass plates in a fixed distance TFTs: a-Si (pc-Si: better perfomance but requires higher deposition T)

MANUFACTURING PROCESS

High precision process/Over 300 individual steps

Class-10 cleanliness/Less than 10 particles per cubic feet

THE FINAL STRUCTURE

Liquid Crystal is filled between two glass substrates: TFT-array glass Color-Filter glass

THE 3 SUB PROCESSES

1. THE ARRAY PROCESS

TFT production in the rear glass Color Filter Application in the front glass

TFT PRODUCTIONTHE DESIRED STRUCTURE

TFT PRODUCTION

A total of 6 layers x 8 processes = 48 processes is required Between developing and etching a baking process also exists

COLOR FILTER APPLICATION

A total of 4 layers x 5 processes = 20 processes is required The baking process is indispensable because a different mask is employed in the next exposure process The pixels are of different height/an extra layer is coated

2. THE CELL PROCESS

2. THE CELL PROCESS

3. THE MODULE PROCESS

Applied Materials

Nikon/Canon

Tokyo Electron

EQUIPMENT FOR MANUFACTURERS

Tokyo Electron

Hitachi/Hitachi Hi-Tech

Jusung Engineering

Joyo Engineering

PROCESS COMPANY G-SIZE

PECVD APPLIED MATERIALS 1-8.5

SPUTTERING APPLIED MATERIALS 5-8.5

TFT-INSPECTION APPLIED MATERIALS 2-8.5

RESIST COATER/DEVELOPER TOKYO ELECTRON 3.5-8.5

PLASMA ETCH/ASH TOKYO ELECTRON 3.5-8.5

OLED BACKLIGHT TOKYO ELECTRON 8.5OLED BACKLIGHT TOKYO ELECTRON 8.5

SEAL DISPENSER HITACHI 1-8.5

CELL ASSEMBLY/INSPECTION HITACHI 1-8.5

CF APPLICATION HITACHI HI-TECH 2-8

PI PRINTING JOYO ENGINEERING 2-7

TFT/CF PATTERN TRANSFER NIKON 6-8.5