Technology Trend of Flexible Displays

Transcription

1 True Leader in Digital World Samsung SDI Technology Trend of Flexible Displays Samsung SDI Display R&D Center

2 Content Display Trend Flexible Displays Recent Research & Developments Market Forecast Technical Issues Display Device Driving Device Substrates & Barrier/Encapsulation Process & Manufacturing Business Opportunities Final Remarks 2

3 Display Trend 3

4 Display Evolution 1 st wave (CRT) Vixlim Thinner 2 nd wave (FPD) 103 PDP 100 LCD 2 VGA Full HD Thinner Larger High resolution Cheaper 3 rd wave (FD) E-paper AMOLED Thinner Cheaper Lighter Larger Stronger 4 th Wave (3D) Virtual image Larger, Thinner, Higher Resolution, Cheaper, Lighter, Virtual Image 4

5 Flexible Displays 5

6 Flexible Display R&D: Worldwide Europe The cluster of The cluster of plastic devices plastic devices : :FLEXIDIS, POLYAPPLY, SHIFT, OLLA (C1) NAIMO (NMP), ROLLED,CONTACT M USA Flexible display Center: Arizona State University (Army Awards ASU $ 43.7 Million) USDC (United States Display Consortium) R&D Projects for Flexible Displays $ Million Japan TRADIM (Technology Research Association for Advanced Display Materials) NEDO : High Performance OTFT, Printable OTFT 6

7 Flexible Display R&D Map E-paper Siemens LG Philips Seiko watch Bridgestone SIPIX LG Philips LCD Citizen OLED

8 Market Forecast Flexible Display Market Forecast < isuppli, March 2006> Global market revenue for flexible display panels will reach US$339 million in 2013, rising at a compound annual growth rate (CAGR) of 83.5% from US$5 million in [isuppli, 2006] 8

9 E-paper Market: Japan Japan e-paper shipments reach 129 million units in fiscal year 2006 (April 2006 ~ March 2006) reach 154 and 208 million units in fiscal year 2008 and 2010 Japan e-paper shipment value reach billion yen (US$ 94.7 million) in fiscal year 2006 reach billion yen in fiscal year 2008 E-paper market billion yen in fiscal year 2010 ASP (average selling price) will be boosted by the migration to color and larger-sized displays [Yano Research Institute(2006)] 9

10 E-paper Products Company Product Specifications When IRex Sony Tianjin Jinke Electronics 8.1, 16 gray scale, B/W Touch panel/ writable device Wireless/memory card 6, 800x600, 4 gray scale, B/W BBeB (Broadband e-book) Price: 300 ~ 400 US$ 6, 600x800, B/W Touch panel & Memory card 2006/4 2006/6 2005/12 Hitachi Fujitsu 13.1, 1024x768 Bridgestone QR-LPD 13.1 (QVGA) & 7.8 (VGA) Reflectance 25%, C/R 4:1, 4096 color Thickness 0.75mm, Cholesteric LCD 2006/8 2008/? 10

11 Technical Issues 11

12 Flexible Displays [Thin Film Encapsulation] EL Layers [EPD, ECD, LCD] [a-si TFT, LTPS TFT, OTFT] [Substrates (plastic, metal foil)] [Flexible Display Structure] *EPD : Electrophoretic Display *ECD : Electrochromic Display *LTPS: Low Temperature Poly Silicon *OTFT: Organic TFT Spacious Thin & Light-weight Rugged Paranomic Low Cost Design-free 12

13 Flexible Display Devices Display Technologies Research Institution Nematic SEC, Sharp, Matsushita, Sanyo, Hitachi Liquid Crystal 3 stack Guest/Host Toshiba Cholesteric Kent Display, Minolta, Fujitsu, Kodak, Matsushita ZBD ZBD OLED Electrophoretic Electrochromic Twisting Ball Thermal Rewritable BTN PNLC Printable LCD Low Molecule Polymer Capsule type Particle type Organic type Inorganic type Seiko-Epson DIC Philips SDI, Pioneer, Sanyo, Kodak, Sony CDT, Dupont, Philips, Sumitomo E-ink, Sipix, TDK Canon, Copytele, IBM, Bridgestone Ntera, Simens, Acreo Sony, DIC Xerox Ricoh, Toshiba, Mitsubishi 13

14 Electronic Paper Display Cholesteric LCD (Kent Display) Not ink-on-paper look Color require 2 or 3 panels Require polarizers and birefringent free substrates Temperature dependence Passive matrix driving 14

15 Electronic Paper Display Electrophoretic Display (E-ink) fluid Electro-Phoretics Active matrix driving Color CF or colored particles Slow Response time E-ink(2005) LGP(2006) 15

16 Electronic Paper Display Quick Response-Liquid Powder Display (Bridgestone) Time (m sec) Hitachi(2006) Bridgestone(2006) Bridgestone(2006) 16

17 AM-LCD Cell gap control Back light unit Alignment layer Handling 7 inch VGA (640x480) Plastic LCD 17

18 AM-OLED Small Molecule Cathode Electron Transport Layer Emission Layer HTL HIL Anode Substrate PLED Cathode Emission Layer HTL Anode Substrate Light!!! Thin Film Encap LiF HBL HTL PDL HIL IZO Reflector Top emission structure Cathode ETL EML Top emission merits: Much deeper color coordinates Higher efficiency Higher aperture ratio Recent key technologies Transparent encapsulation High efficiency (Transparent cathode tech: Optimized for max. light output) Good color coordinates (µ -cavity effect simulation etc.) 18

19 Flexible Backplanes Driving Device a-si TFT Poly-Si TFT Organic TFT Transfer Tech. the Others Features Well established TFT-LCD industry Low mobility ~1 cm 2 /Vsec Typical deposition temperature ~ 300 C Low temperature (~ 150 C) a-si TFT process feasible High mobility ~ 100 cm 2 /Vsec Both NMOS and PMOS TFTs available Typical process temperature ~ 450 to 600 C Ultra LTPS process (~150 C) is being developed Mobility ~ 1 cm 2 /Vsec Very low temperature processing (< 150 C) Technology is being developed Printing Very low temperature processing Not compatible with low-cost objectives Seiko-Epson, Sony, Philips - Oxide TFT, Nanowire-TFT, CNT-TFT, FSA 19

20 Technical Issues Process Issues Flexible Substrate Handling Dimensional stability during process adhesives Handling issue Mechanical stress Material Stability & Reliability Interface control Poor device performance Large defect density High Rs: S/D contact Plastic/Flexible substrate Glass Carrier 1) Adhesives 2) Thin film with glues 3) Frame for substrates 20

21 Transfer Tech. EPLaR Process 21

22 Oxide TFT & CNT TFT 5x3 array CNT TFT SWNT channel(<10 nm) Source PEN Drain S/D, Gate: IWO (In, W) 2 O 3 (W 1%) L/W = 40µm/100µm Oxide TFT HMDS Gate Mobility: 0.5cm2/Vs On/off ratio: 10 4 Polyimide Issues - remove metallic SWNT - Inkjet printing: process - Cost Field effect mobility: 28 cm2/vs Threshold voltage: 19 V Gate voltage swing: 1.39 V/dec. On/off ratio: Large area 22

23 Organic TFT: Issues Channel layer: π-conjugated material design, synthesis, refining process, coating & printing, patterning Passivation S/D Channel S/D Gate Dielectric Plastic substrate Packaging TFT array S/D electrode : thin film deposition, Patterning (Au, Ni, Pd, SOM, conducting polymer) G/I : deposition, material design & synthesis, Refining process, Organic polymer Substrates : PET, PEN, PC, PAR (CTE, thermal stability, WVTR, OTR) Gate electrode : thin film deposition, Patterning (Metal (Al), SOM, conducting polymer) Au (5.0eV) LUMO Au sputtering litho process Coating or printing UV process + HOMO + Energy gap π-electron soft 23

24 Flexible Substrates Flexible Substrate Bare Plastic Film Ultra-high Barrier Coating Chemical Resistant Coating Transparent Conductor Coating CTE, Rigidity Water uptake Chemical resistance Optical transparency Surface roughness Optical birefringence Porosity H 2 O permeation rate < 5 x g/m 2 /day oxidation of 10 Å metal in 10,000 hours Stable to aggressive chemicals (photolithography) Present a smooth surface for thin OLED layers Dimensionally stable to T, RH cycling Optical clear and transparent Flexible and scratch resistant Inexpensive 24

25 Encapsulation Requirements for Thin Film Encapsulation OLED Passivation Good barrier properties < 10-6 gm/m 2 /day for H 2 O < 10-6 ml/m 2 /day/atm for O 2 Thermal stability and long-term photostability Flexible Transparent Substrate Time evolution to permeation process Adhesion to substrate Defect-dominant permeation process Suitable for large areas Prolonged pathway 25

26 Encapsulation GE Vitex Sys. Pioneer Multilayered structure Barrier - Decouple defects - Continuous Composition Transition (SiO x N y : Inorganic/SiO x C y : Organic) - Enhanced adhesion - High optical transmittance - PECVD deposited inorganic layer WVTR & OTR depend on barrier layer & structure 26

27 Gravure Printing Good Extremely high throughput Can print different amounts of ink in different areas Low viscosity inks Can print particulates and polymers Bad Discrete dots Substrate needs to be smooth Expensive to make plates 27

28 Thermal Transfer Good Bad Dry Thin ink layers Clean Good for polymers Thermal decomposition Low throughput Can t make thick ink layers 28

29 Inkjet Printing Good Low material consumption Non-contact High resolution (with patterned substrate) Can build up thick layers Low viscosity inks Can use small amounts of materals Bad Low throughput Ink spreading constrain drops Doesn t print continuous lines Print head solvent compatibility Coffee stain Challenge 1. High resolution Exact landing onto the small pixel Challenge 2. Large-sized display Exact droplet landing under high-speed head movement 29

30 R2R Process Current Hurdles in R2R Process Damage due to handling Particle generation Impurity due to contact Yield management Linear processing Bending -Stress - Cracking - Delamination (shear stresses) ITO Surface contamination Semiconductor interface Substrate Distortion - Thermal expansion - Moisture changes - Film tension 30

31 Business Opportunities 31

32 Applications for Business 32

33 Business Opportunities (Phase I) E-paper business is on the rise (low cost display) Who are the players: Hitachi(2010, 1000million US$), Sony, Fujitsu, NEC, irex, Citizen, Teraoka, Ishida, etc. Application: e-book, information media, watch, price tag, signage, POP, etc. 33

34 Business Opportunities (Phase II) Flexible e-paper business is coming Who are the players: Plastic Logic, Polymer Vision Application: Mobile Display, e-note, e-book, etc. Polymer Vision (Philips) 5, QVGA, 16 Gray scale 85ppi, C/R 30:1 ~40:1 (2007 business plan) Plastic Logic A4 size (2008 business plan) 34

35 Business Opportunities (Phase III) Ultra thin and light-weight & rugged display Quality & cost comparable to conventional FPD First make some quality display, and then see.... Thinness adds value [Samsung SDI 2006] [5.6 Flexible AMOLED (thickness 150 µm] 35

36 Business Opportunities (Phase IV) Connectivity Wireless network smart & interactive devices Ubiquitous & Convergence e-watch, e-wallet, smart table, smart-shelf, etc. [Nokia, October 2005] [Blue-sky presentation at the HP Mobility Summit, May 2006] 36

37 Final Remarks 37

38 Final Remarks Business Issues - E-paper market is coming see what will happen - Lighter, thinner and rugged displays be with the display trend - Low cost manufacturing #1 priority - Develop killer application & Find something new - Design free: interior design & fashionable shape - Other infrastructure network, device convergence, Technology & Manufacturing Issues - Develop flexible materials - Substrate distortion during process - Substrate handling & thin film encapsulation - Robust process at low temperature - How to use conventional facilities - Develop printing & R2R - Be with such devices with Sensor, RFID tag, memory, solar cell, lighting, etc. 38