[1.8] CF/ 액정 / 모듈공정
Color Filter Process 3
C/F Pixel 구조 R G B R G B R Stripe 형태 R G B R G B R R G B R G B R Red Common Electrode (ITO) Over Coat Green BM Open Blue Glass Substrate Black Matrix
Color Filter Photo 설비 Proximity Exposure System Mirror u.v. Proximity Gap Parallel-light MASK (Reticle) Glass Substrate Stage (Fixed)
Color Filter 제조공정 Glass 세정 (Cleaning) Cr/CrOx Depo Cr/CrOx Etch Red pattern( 도포 / 노광 / 현상 /Cure) Green pattern( 도포 / 노광 / 현상 /Cure) Blue pattern( 도포 / 노광 / 현상 /Cure) UV Ashing OC Coating
Color Filter Photo 공정 u.v. MASK (Stripe RGB Pattern) Proximity Exposure Exposure Negative Color PR(Red) Red Develop & Bake BM Negative PR: 빛을받은 PR 이남음주로 (Color PR, 유기절연막등등 ) Positive PR: 빛을받은 PR 이제거됨 (TFT PR, 유기절연막.BM)
(1) Fabrication of Black Matrix Reduction of Surface Reflection CrOx: Dn x d=1/4 l ~ 500A Cr: 1500A BM CrO x : 500A CF Glass Substrate Destructive Interference Formation of low reflection black-matrix using CrOx/Cr or Organic BM
(2) Red Color-Filter Pattern u.v. MASK (Stripe RGB Pattern) Proximity Exposure Exposure Negative Color PR(Red) Red Develop & Bake BM Figure 109. Making a Red color-filter pattern
(3) Green Color-Filter Pattern u.v. MASK (Shifted by a pixel pitch~100mm) Exposure Negative Color PR(Green) Red Red Green Develop & Bake
(4) Blue Color-Filter Pattern MASK (Shifted by a pixel pitch) u.v. Negative Color PR(Blue) Exposure Red Green Red Green Develop & Bake Blue
(50 Common Electrode ( ITO Deposition) Over Coat Common Electrode (ITO:1500A ) R G B Black Matrix (a) Color-filter with planarization process Common Electrode (ITO:1500A ) R G B Black Matrix (b) Color-filter without planarization process Deposition of common electrode using ITO sputtering
R,G,B 공정 Step Soft baking 잔존 solvent(20~30%) 제거노광부 / 비노광부의 contrast향상 Polymer Tg 공정으로평탄성높임 PR과 glass와의접착력을강화시킴 -. 잔존solvent를제거하면현상시에비노광부의막의현상액에대한내성을증가함. -. Tg( 유리전이온도 ) 이상으로가열하면서 film이 annealing됨. Exposure Development Hard bake Photo crosslinking 반응이발생 : Mask 의 image 를 PR 위로전사공정 노광방식으로 Aligner, Scan 방식 Pattern 형성공정 : 비노광부가현상액에의해제거됨. 현상액 : KOH, Na 2 CO 3 solution 잔존모노머의열경화반응 막의열적 / 기계적내성을가지게함. -. Photo crosslinking 반응 1) 노광부에서광개시제라디칼발생 2) 모노머중합, 연쇄반응, 3) 막이 crosslinking 됨. 4) 최근 binder 가 X-linking 에참여함. -. 노광부 / 비노광부용해도차이에의해패턴형 성 -. 노광부는경화에의해현상억제됨. -. 비노광부의 binder polymer 의 COOH 가알칼 리 현상액에녹으면서현상이됨. -. 일정수준온도가올라가면잔존모노머가 열경화반응이일어난다. X-linking density 가증가하면서열 / 화학적 / 기계적내성을가지게된다.
R,G,B 공정 Photo cross-linking 반응 Photo cross-linking 개념도 P I COOH P COOH P P I P COOH P I COOH P COOH P P COOH P P COOH COOH P 노광전 or 미노광부 Soluble to Developer 노광후 ( 노광부 ) Insoluble to Developer
R,G,B 공정 Color PR 개념도 1) Binder Polymer : Base polymer 2) 모노머 : 가교제, polyester acryl 화합물 3) 광개시제 : 빛을받아서라디칼을발생 4) 안료 : PR 에색상부여 5) 용제 : 각종성분용해및도포성부서 6) 첨가제 : 도포성향상제, 안료분산성향상제및접착력항상제
Liquid Crystal Cell Process 22
Liquid Crystal Cell 구조 Common Electrode(ITO) Black Matrix Polarizer Color Filter Color Filter 5 Short 4 Seal 1 Alignment Layer TFT-Array 3 Spacer Bonding PAD TFT 2 L/C Polarizer Pixel Electrode(ITO)
LC Cell Process Flow-Chart TFT-Array Substrate 1 Alignment Layer Print 2 Rubbing 4 Seal Print 5 Short Dispense Color Filter Substrate 1 Alignment Layer Print 2 Rubbing 3 Spacer Spray (c) Cell Scribe & Break (d) L/C Injection & End Seal (e) Visual Test (a)substrate Assembly (b)seal Line Hardening (f) Polarizer Attach Module Assembly
TFT-Array & Color-Filter panels 1 Alignment Layer Print Dispenser Alignment Layer Alignment Layer (T<1000A ) Substrate Roller Roller Rotation PI MASK Stage Move Coating of an alignment layer using offset printing system
PI Print Dispenser : PI 용액적하 Doctor Roll : Anilox Roll 표면에균일한 PI 막형성 Anilox Roll : Dispenser 에서적하된 PI 용액을보존 APR Plate 에 PI 용액전사 APR Plate : 전사받은 PI 용액을기판상에인쇄 PI 막두께 Control -> 인쇄속도, Doctor Roll & Anilox Roll 사이의 Gap, PI 막재료의농도
2 Rubbing LC 배향 (Rubbing) 공정 LCD 를만들기위해서는액정분자들을일정한방향으로배열시켜야한다. Alignment Layer Substrate Roller Rotation Stage Move L/C Molecule Alignment Layer Glass Substrate
액정과 배향막 Rubbing 에 의한 액정의 배향
액정과배향막 Rubbing 에의한액정의배향
3 Spacer Spray Color-Filter Only Density of Spacer : 1~2 Spacers/pixel N 2 Gas Solvent Spacer Color Filter Color Filter (a) Wet Type (b) Dry Type
Column Spacer Spacer 비교 (1) 1 Beads Spacer Glass ITO Pixel Black Matrix Alignment Film Liguid Crystal TFT ITO Glass Alignment Film Bead Spacer 2 Column Spacer Glass ITO Pixel Black Matrix Alignment Film Liguid Crystal TFT ITO Alignment Film Glass Column Spacer
Column Spacer 개요 [ 참고 ] Spacer 비교 (2) 장 / 단점 Beads Spacer Column Spacer 장점 - 공정원가낮음 - 공정이간단 (Spacer 산포 ) - 후공정영향이적다 - 균일한 Cell Gap 유지 - Pixel내 ( 개구부 ) Spacer가없으므로 black 휘도상승없음 - Contrast 향상 - Beads무라없음 단점 - 산포밀도수불균일에의한 Cell Gap 영향이심함 - Pixel내 ( 개구부 ) Spacer에의한휘도저하및 Contrast 저하 - Spacer 주위빛샘 - 옹달샘현상 ( 가압시 ) - 진동 / 충격에취약 - C/F 재료비많음 - C/F 공정수가많음 (Coating, 노광, 현상, OVEN) - 후공정 Margin 부족 (PI Print, Rubbing, Seal Ass y & HP) - 신뢰성 ( 가압 Test) Smear 불량유발
Column Spacer < 참고 > C/S 적용 C/F 제조공정 Bare B/M Red Green Blue Glass 세정 Spacer Coating ITO Column Spacer Exposure Develop Hard Bake
4 Seal Print TFT-Array Only Screen Mask Sealant Sealant Dispenser Seal TFT-Array Alignment layer Seal TFT-Array TFT-Array L/C Inlet Alignment Layer Two types of seal print system
5 Short Dispense (TFT-Array Only) Common Electrode(ITO) Color Filter Spacer Bonding Pad Short TFT-Array Alignment Layers Seal Dispenser LC Inlet Formation of electrical shorts between two substrates
(a) Substrate Assembly TFT-Array Substrate 1 Alignment Layer Print 2 Rubbing Color Filter Substrate 1 Alignment Layer Print 2 Rubbing Color Filter Substrate Spacer 4 Seal Print 3 Spacer Spray 5 Short Dispense (a)substrate Assembly Short TFT-Array Substrate Seal (b)seal Line Hardening Substrate align and assembly
상하판 Assembly & Hot Press (CS beads spray) Seal 그리기 ( Seal Dispensing ) C/F TFT SHORT & SPACER 산포 BEADS SPACER 합착 ( Assembly 후 Hot Press) Cell Gap Control Spacer Spacer 미사용 위치 Random
상하판 Assembly & Hot Press (CS pattern case) Seal, Short onto column spacer 형성 C/F 액정 drop (one drop filling) TFT 진공합착 Spacer Column Spacer Spacer 미사용 Cell Gap Control 위치 random Uniformity 개선 위치고정
(b) Seal Line Hardening Substrate Pre-Allign Hot Press: Sealant Curing & Cell Gap Control Hot Press (~180 ) C/F Substrate Seal Short Spacer TFT-Array Substrate Sealant hardening and cell gap control
(c) Cell Scribe & Break Scribe Line Scribe and breaking L/C cells
(d) Liquid Crystal Filling Process X LCD Cell Pump N2 Seal _ V L/C Inlet L/C Vacuum Chamber Chamber Pressure N 2 In _ V N2 Touch t Start Injection Pump X Vacuum filling of liquid crystal
(d) Liquid Crystal Drop Fill ( 적하공정 )
(d) End Seal L/C Inlet Liquid Crystal End Seal Short Seal Seal Spacer End Seal (uv sealant) Cell gap control and end seal of L/C cell
(e) Visual Test & (f) Polarizer Film Visual Test Bonding Pad Polarizer Edge Grinding Polarizer Visual test and polarizer attachment
Polalizer 부착 편광판접착제면의이형필름을제거하여접착제를노출시키고, 원통형고무 Roll 로눌러서 Cell 에접착시킨다. Cell 이형필름 편광판 편광판부착공정에서불량의 90% 정도는이물질혼입에의해일어난다. (Glass Chip, 편광판절단면에부착된이물질, 공기중에부유하는 Particle) -> Panel 양면의세정이필요함.
모듈공정 47
Module 공정 Flow Chart LCD Panel PCB & IC Parts TCP bonding SMT Process LCD Panel Test Repair Test PCB Soldering Driving Test Backlight & Chassis Ass y Backlight & Chassis Units TCP PCB Test Repair Aging Final Test Shipping Chassis B/L Unit
TCP & COF TCP (or TAB) - Tape carrier Package의약자 - Lead frame 구실을하는패턴이들어있는 Tape를사용하여 Bonding. - Film 형태의 PKG COF - Chip On Film 의약자 - TAB처럼 Film위에 device hole을만들지않고, Cu패턴을형성하여 film위에 bonding. - Film 형태의 PKG TAB COF
COG Chip On Glass 의약자 :Driver IC 를 Panel 에직접부착하는실장기술 d c a b a FPC (Flexible Printed Circuit) b Driver IC c ITO pattern (Indium Tin Oxide) d LCD (Liquid Crystal Display)
OLB (Outer lead Bonder) 공정 구동용 Drive-IC( 집적회로 ) 를이방성도전 FILM (ACF: Anisotropic Conductive Film) 을이용하여열과압력을이용하여연결및부착하는공정. Insulating silicon rubber Protective Films TCP Conducting Carbon Particles Thermal Press Hot Bar ACF Cu Lead (TCP) Bonding PAD W TFT- Array
ACF 의구조및 conduction
OLB Process Pol CF Glass( 상판 ) TFT Glass( 하판 ) Gate S/D
PCB Bonding Process PCB BONDING - TAB IC 와 PCB 사이에이방성도전 FILM(ACF) 을놓고열과압력을가하여 TAB IC 와 PCB LAND 사이를수μm이하로근접시켜도전입자로전극간의전기적통로를형성하고계속하여충분한 열량을인가함으로써 ACF 의주성분인 EPOXY 를경화시켜접착력을부여하는공정.
PCB Bonding Process
Silicon Dispenser Process Si Dispenser 외부에노출된 COLOR FILTER 및 OLB Pad 부가습기에의해부식되는것을방지하고, 외부충격으로부터보호하는목적으로실리콘또는 BOND 를도포하는공정. [A- A' 단면도 ] - 1 -
Si Dispenser Process
기구조립 Process 기구조립이란? ASS'Y(PANEL & BACK_LIGHT ASSEMBLY) 제품의각종요소에해당되는부품과기타기능성자재를제조설비및각종 JIG류, ASS'Y TOOL류등을이용하여조립함으로써, 상품으로서의가치가내포된완제품단계로서의최종공정을일컫는다..
Back Light Unit PRISM SHEET DIFFUSER LAMP LGP (Flat Type) LAMP L/Reflector MOLD FRAME REFLECTOR SHEET 직하방식 평판방식 (Flat Type) LAMP LAMP LAMP LGP L/Reflector LGP (Wedge Type) LGP PATTERN REFLECTOR SHEET Edge 방식 경사방식 (Wedge Type) 광원위치에따른방식 LGP 형상에따른방식
완성된 TFT-LCD module 구조 2 Driving Circuit Unit TCP PCB LDI 1 LCD Panel Color Filter Substrate TFT-Array Substrate 1 LCD Panel TFT-Array Substrate Color Filter Substrate 2 Driving Circuit Unit LCD Driver IC (LDI) Chips Multi-layer PCBs Driving Circuits Chassis Lamp LGP 3 Backlight & Chassis Unit 3 Backlight & Chassis Unit Backlight Unit Chassis Assembly