1 CNT-FED Part I Yesterday and Today Min Hee Cho, Changhwan Shin, Wookhyun Kwon

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CNT-FED Part ICNT-FED Part IYesterday and TodayYesterday and Today

Min Hee Cho, Changhwan Shin, Wookhyun Kwon

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RoadmapRoadmapRoadmapRoadmap

Part III: Application & marketing strategy * Target application (HUD) * Marketing strategy * Business Plan

Part I : Yesterday and Today * Display technology summary CRT LCD FED * Current CNT FED technology and limitation

Part II : New technology * AM (Active matrix) CNT-FED * Transparent CNT-FED for HUD (Head up display)

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Outline for CNT-FED Part I1. Introduction

- CNT & Application- Depending Champion : LCD- Quick review for FED

2. Technology for FED & CNT 2.1 FED development

- from CRT to FED- Pixel control in FED- FED history- Performance competition

2.2 BLU (Back Light Unit)- Local Dimming- LCD vs BLU

2.3 CNT merit- The technology for CNT emitter- Issues in CNT emitter

- Common issue 3.Summary

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Outline1. Introduction







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1. Introduction - CNT -

Single-walled CNT Double-walled CNT Multiwalled CNT

Diameter : 1/100,000 of a hair (1-100nm)Thermal conductivity : 10 times of diamondStrength : more than 2 times of spider’s threadUltra high current densities : 1010 A/cm2 (Cu : 107 A/cm2)

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Application

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Depending Champion in Flat Display : LCD

LCD

CRTWho is Next?

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Quick review for FED

Why FED ! * low power (30~50% of LCD,PDP) * very high contrast level * light weight (compared to LCD) * very slim (compared to LCD) * be able to make up for loss pixel dream of display !!

FED : Field Emission Display

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2. Technology for FED & CNT

from CRT to FED : CRT

* CRT advantage - high contrast levels - very fast response times Now disappear…

Because of Thickness & Power

* CRT operation Powered by an electron gun Thermionic emission (Boiling" them off a metal filament) Scanned across the screen

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from CRT to FED : FED structure

* Main difference : Many electron guns : Sharp tip : Field emission Thermionic emission vs Field emission (FED)

* Emitter : field electron sources to provide electrons strike colored phosphor produce a color image.

* In order to maximize performance : Carbon Nanotube (CNT) technology

cones (Spindt tip)

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Normal

Bad Pixel

Bad Pixel in LCD

Computer Synthetic beauty

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Bad Pixel in LCD

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Pixel control in FED

Technical Advantage : increase yield (reduce the pixel loss)

So tiny and many tips :

in some pixels being inoperable find the dead emitters corrected by slightly increasing the pulse (make up for the loss )

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FED history1991

FED systems started

1997 2000

2003 2004

spindt type was researched

Micro tip Full color FED CNT FED

-38” CNT FED TV

~Now

CNT BLU Prepare CNT FED mass production: But not yet

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Performance competition

• High Contrast• Wide Viewing Angle• High Resolution• Color Gamut• Fast Response• Resolution• Energy Saving

The performance should be satisfied to be a future FPD TV.

Major requirement

ITEM FED LCD PDP

Brightness ☆ ☆ ☆

Contrast ★ ☆ ☆

Color gamut ★ ★ ★

Brightness Uniformity ☆ ☆ ★

Power Consumption ★ ◎ ○

Response time ★ ○ ☆

View angle ★ ○ ☆

Gray scale ☆ ☆ ☆

Resolution ☆ ★ ○

Weight ★ ★ ★

★ :Excellent☆:Very Good◎:Good○:Intermediate

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2.2 BLU (Back Light Unit)

The advantage of LCD + FED

Back light

Use the Current LCD technolgy: Color gamut &Uniformity

Use the light source in FED: Brightness & Efficiency

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Local Dimming

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LCD vs BLU

Fast motionBlinking BLUDynamic BLU

CNT is used for an electron emitter in both CNT-FED and CNT-BLUwith many common technologies.

Natural color

Local Dimming

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2.3 CNT meritCNTs1> Small tip radius : The efficiency of the field emitters2> High aspect ratio3> High conductivity

Materials and Design 28 (2007)

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The technology for CNT emitterPaste emitter

Directly grown emitter

Low cost / Large area

catalyst dot

PECVD

Uniform CNT length / Possibility for higher resolution FED

http://images.google.com/imgres?imgurl=http://homepages.ed.ac.uk/aa01/images/tube2.gif&imgrefurl=http://homepages.ed.ac.uk/aa01/tube_mech.html&usg=__mp7D92Df7EQ5Z3Rxp39dy4pbXxc=&h=400&w=317&sz=26&hl=ko&start=1&tbnid=asXr-aDsu7SbZM:&tbnh=124&tbnw=98&prev=/i

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Emitter type Issues Target Approach

Paste

emitter

Emitter length uniformity

> 70% (1 - σ/μ) Raw CNT control

Residual minimized Paste composition

Directly

grown emitter

(CVD)

Large area deposition

system development

> 40” Collaboration with

machine maker

Diameter decrease

> 5nm @ 450C *Catalyst control

*Precursor control

Issues in CNT emitter

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Common issue

Target value Technology

High voltage stability

10~15kV Charge drain structure

Lifetime 30,000hr *use rigid CNTs

*Operation condition optimization

Brightness efficiency

60~70 lm/W * Anode screen optimization

* Cathode emission fill factor improvement

* Operation condition optimization

Due to - Inter-pixel uniformity- Life time

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Summary for Part I

◆ CNT FED picture quality is quite comparable to conventional LCD or PDP device

◆ CNT Backlight have superior capacity to express high image quality such as high contrast

and low power consumption

◆ CNT is most promising material for FED

◆ There still remain some obstacles : High voltage stability , Lifetime , Uniform fabrication , Large area process

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CNT-FED Part IINew Technology for CNT-FED


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OutlineOutline

1. New approach for the current CNT-FED:1. New approach for the current CNT-FED: AM (Active-Matrix) CNT-FEDAM (Active-Matrix) CNT-FED

2. Transparent CNT-FED for HUD:2. Transparent CNT-FED for HUD: SWNT-SOG composite for transparent FEDSWNT-SOG composite for transparent FED

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OutlineOutline



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Current CNT-FEDCurrent CNT-FED

1. Why CNT?

nano-size tip, high-aspect-ratio, high stability ideal field-emission material

2. Current CNT emitter structures

Spindt-type CNT emitter fabricated by paste method

Under-gate-type CNT emitter fabricated by paste method

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Technical IssuesTechnical Issues

#0: no high-efficient low-voltage phosphor

accelerating voltage > 7kV; spacer charge

#1: no ideal triode emitter structure

#2: hard to implement inter-pixel uniformity

#3: Lifetime is not guaranteed (due to heat)

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Alternative technology: fabricationAlternative technology: fabrication

Other issues: 1) Difficulty to implement the ideal triode structure with CNT

2) Spacer; high accelerating voltage required.

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New approach for the current CNT-New approach for the current CNT-FED:FED:

AM(Active-Matrix)-CNT-FEDAM(Active-Matrix)-CNT-FED

AM-CNT FED panel view (top), and its cross-sectional view (bottom)

AM-CNT FED panel view (top), and its cross-sectional view (bottom)

Amorphous-silicon TFT (a-Si TFT) used for the switching device in LCD is utilized to control the CNT emitters in the AM-CNT FED.- a-SI TFT integrated with the cathode-plate; Address TFT & Driver TFTs

- TMG; gating to induce electric-field emission and prevent anode’s electric-field, integrating e-beams

- Anode plate with R/G/B phosphor, and Spacers supporting vacuum-packed emitters

- Operating VDD only depends on TFT characteristics, due to signal inputs on G/S of the TFTs

Tapered Macro-Gate

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Possibility of the AM-CNT FEDPossibility of the AM-CNT FED

Luminescence vs. anode voltage at the TMG-CNT emitter

No high-efficient low-voltage phosphor Accelerating voltage (> 7kV) required.

Alternative: TMG can obtain the required accelerating voltage of the anode.

Emitted e-beams can be integrated at the anode’s phosphor by TMG

Prevent cross-talk

AM-CNT

PM-CNT

Transfer (top) and output (bottom) characteristic of the series-connected a-Si TFT

Low IOFF at higher VDS

Saturation region > 150V; less σ(Iop) uniformity

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OutlineOutline



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Transparent CNT-FEDTransparent CNT-FED

Flowchart of fabrication process for the transparent CNT-FET based on a composite of SWNT and SOG.

Tin-oxide-coated glass

** Arc discharge method to synthesize SWNT

CleaningCleaning

Tin-Oxide-coated glass substrate used to synthesize the SWNT

The SWNT film was purified, by ethanol treatment, to increase the adhesion of SWNTs with the substrate.

The SWNT film was oxidized, to burn out amorphous carbon and oxidize the metal catalyst.

The purified SWNT film spin coated with SOG solution, then heated to remove moisture and solvent.

The film was exposed out of SOG by etching the top surface of the composite film in diluted HF solution.

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SummarySummary

- AM-CNT-FED can overcome the current CNT-- AM-CNT-FED can overcome the current CNT-FED technical issues.FED technical issues.

- Transparent CNT-FED can be fabricated - Transparent CNT-FED can be fabricated cheaply and demonstrated.cheaply and demonstrated.

ReferenceReference[1] ETRI annual research report[1] ETRI annual research report

[2] Nguyen V. Quy et al., “SWNT-SOG composite for transparent field [2] Nguyen V. Quy et al., “SWNT-SOG composite for transparent field emission device,” Journal of Crystal Growth, Sep. 2008. emission device,” Journal of Crystal Growth, Sep. 2008.

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CNT-FED Part IIICNT-FED Part IIIApplications and Marketing StrategyApplications and Marketing Strategy


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OutlineOutline

ApplicationsApplications

CNTCNT Head-up Display (HUD)Head-up Display (HUD)

Marketing Strategy for CNT-HUDMarketing Strategy for CNT-HUD

• Market SizeMarket Size

• Target CustomersTarget Customers

• SWOT AnalysisSWOT Analysis

• InvestmentInvestment

ConclusionConclusion

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Application

Flat Panel Display Back Light UnitHead-Up Display

(H.U.D.)

Market Size

• Largest single market

• Large • Niche

Risk• Highly competitive

• Competitive• Small market size

Competitor

• LCD• PDP

• CCFL• LED

• Laser hologram• LED projection

Requirement

•High quality image•High speed response

• Low cost• Brightness• Low power

• High transparency

Investment

Min. $100 million(Samsung: $840 million)

Min. $10 million(CMO: $19.4 million)

Min. $1 million

Target ApplicationTarget Application

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Older Head-Up DisplayOlder Head-Up Display

Major technologies Laser Hologram

Military and Civilian Aircraft

< Targeting> < Navigation for night landing>

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Head-Up DisplayHead-Up DisplayAutomobileAutomobile

HUD in BMW 7 series

Mounted on the dashboard Projecting information onto the windshield Available only for luxury cars

Major technologies TFT-LCD projection LED projection

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Drawbacks of Old TechnologiesDrawbacks of Old Technologies Laser Hologram

Dashboard Projection

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• Limited functionality

• Lack of clarity

• Insufficient brightness

“The first HUDs, failed to wow the consumer as hoped.”

“Solid-state electronics new to HUD have produced dramatic improvement”

• More clarity

• More color

• Brighter display

• CNT-FED technology can provide• Transparency• Higher brightness• Clarity• Functionality

CNT-FED technology for HUDCNT-FED technology for HUD

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• 200% lighter and smaller• Support TV like images• Enhance pilot comfort

– Increased head clearance– Increased volume of head motion box – Pilot’s head can’t obscure image

Advanced HUD in AirplaneAdvanced HUD in Airplane

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Telemetric Display can provide an intelligent driving experience!

•Traffic information•Navigation•Video phone•Safety warning

HUD in Entire Front Windshield of CarHUD in Entire Front Windshield of Car

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Market SizeMarket Size

HUD Market to reach $400 million by 2012EE Times (21/Jun/2007) A new research brief from ABI Research has predicted that head-up display (HUD) solutions that display key information in the driver's line of sight, reducing the need to look away from the road ahead, will comprise a Rs.1,634.67 crore ($400 million) market by 2012. The HUD solution addresses raised concerns related to assortment of applications in today's cars, from navigation to information and entertainment that pulls the driver's attention away from the basic task of driving.

Demand for automobile HUD is rapidly growing. The real market exceeds the expectation.

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CompetitorsCompetitors

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Target CustomersTarget Customers

Airplane MakersAutomotive Component

Suppliers

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S.W.O.T. AnalysisS.W.O.T. Analysis

Transparency Higher brightness CRT like images

WEAKNESS

Small market size Reliability and Lifetime Yield

AM-CNT technology

OPPORTUNITY

Growing market Few competitors High price market

• Airplane• Luxury car

THREAT

Old solution providers• Laser hologram• Projection

Major companyPatent protectionI.P. provider

STRENTH

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Development Plane (Phase I)Development Plane (Phase I)

Patents

Proto-type

Promotion

2nd Investment

from Buyers

1st Investment

(Seed Money)+ $ 1000K (1M)

10 patents x $30K = - $300K

- $ 600K

- $ 100K

> $ 20 M

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ConclusionConclusion

CNT-FED is promising technology for future display, CNT-FED is promising technology for future display,

but this has limitationsbut this has limitations

To overcome these limitation, we introduce AM-CNT-To overcome these limitation, we introduce AM-CNT-

FED.FED.

To get product differentiation, we introduce To get product differentiation, we introduce

transparent display.transparent display.

HUD application is good target market to avoid high HUD application is good target market to avoid high

risks at the begging stage.risks at the begging stage.

We are finding angels who invest seed money!We are finding angels who invest seed money!

Documents

1 CNT-FED Part I Yesterday and Today Min Hee Cho, Changhwan Shin, Wookhyun Kwon