OLED Organic Light Emitting Diode Pusan National University

OLED (Organic Light Emitting Diode) Pusan National University Center of Plastic Information System

OUTLINE I. Overview II. 종류 III. 제작과정 IV. 장비 견학 및 설명 V. 실습 Pusan National University Center of Plastic Information System

개략적인 OLED 개발 연대기 Year 저분자 OLED 1963 최초의 유기 EL 특성 확인 (안트라센, 400 V, New York Univ. ) 1982 최초의 특허 (Kodak) 1987 최초의 실제적인 구조 Tang(Alq 3) (Kodak) 1990 PLED 최초의 특허(Cambridge Univ. ) 1997 최초의 단색 제품 출시(Pioneer) 1999 Color AMOLED(Kodak/Sanyo) 2000 Multi-color OLED 휴대폰 탑재 (Pioneer/Motorola) Color AMPLED 보고 (CDT/Seiko Epson) 2001 15. 1 -inch AMOLED 개발(SDI) 17” 풀칼라 잉크젯 AMPLED(Toshiba) 2002 외부창용 OLED 256 color(SOLED) Philips 면도기 첫 PLED 제품 2003 Digital Camera용 디스플레이 시판 (Kodak/Sanyo) 40” Tiled AMPLED 잉크젯 (Seiko-Epson) 2005 21” TV용 OLED 개발(삼성전자) Pusan National University Center of Plastic Information System

Display 비교 구분 OLED LCD PDP FED CRT 응답속도 O(수 s) X(수십 ms) 시야각 O X O O O 백라이트 필요없슴 필요없슴 소비전력 O X X X 두께 O O O X 무게 O O O X 저가격화 O X X O Pusan National University Center of Plastic Information System

Display 비교 LCD CRT LCD projection Pusan National University Center of Plastic Information System

Display 비교 PDP LCD DLP (Digital Light Processing) Pusan National University Center of Plastic Information System

Pusan National University Center of Plastic Information System

Structure Comparison between OLED and LCD AMOLED A-Si TFT /LTPS TFT B/L a-Si TFT / LTPS TFT OLED C/F LC 5 -6 층수 >10 <2 mm 두께 6 mm 3 g 무게 10 g 35 m. W 소비전력 150 m. W <0. 1 m. S 응답속도 >25 m. S -25~65 동작온도 0~50 Pusan National University Center of Plastic Information System

LCD 對比 유기 LED LCD Pusan National University 유기 LED Center of Plastic Information System

미래형 플라스틱 디스플레이 CRT Flexible 디스플레이 Pusan National University LCD PDP 유기 EL Center of Plastic Information System

Flexible 유기 디스플레이의 현황 a) PM-PLED (Du. Pont) b) 스크린 프린팅방법을 이용한 PM-PLED (DNP) c) PM-OLED (ETRI) d) PM-OLED (UDC) e) Full color PM-OLED (Pioneer) Pusan National University Center of Plastic Information System

전도성 고분자 (Conducting Polymers) Pusan National University Center of Plastic Information System

Pusan National University Center of Plastic Information System

청색 녹색 적색 Pusan National University Center of Plastic Information System

Pusan National University Center of Plastic Information System

Pusan National University Center of Plastic Information System

Pusan National University Center of Plastic Information System

1. P-N junction with dopants Pusan National University Center of Plastic Information System

Vacuum zero 2. Bandgap Energy Electron Majority Carriers Vacuum zero Conduction band (empty) Work Function Eg Electrons Holes Ef Valence band (Full) Vacuum zero Electron Affinity Ev Valence band Hole Minority Carriers Work Function Eg Valence band CB Ef CB Ec Ef Donor levels Valence band Hole Energy Electron Energy Work Function n-type semiconductor Vacuum zero insulator conductor semiconductor Electron Minority Carriers Electron Affinity CB Ef Acceptor levels Hole Majority Carriers Valence band p-type semiconductor Pusan National University Center of Plastic Information System

II. 종류 구조: PM OLED AM OLED Bottom Emission Top Emission 형광 재료: 단분자 인광 형광 고분자 인광 Pusan National University Center of Plastic Information System

PM & AM OLED 구조 Pusan National University Center of Plastic Information System

Device Structure of OLED Pixel Depending on Emitting Materials Fl. OLED Cathode Electron Transport Layer Emission Layer Hole Transport Layer Hole Injection Layer Anode Glass substrate Pusan National University Ph. OLED PLED Cathode Electron Transport Layer Blocking Layer Emission Layer HTL HIL Cathode Emission Layer Hole Transport Layer Anode Glass substrate Center of Plastic Information System

디스플레이 구조 Bottom Emission OLED Top Emission OLED Pusan National University Center of Plastic Information System

단분자 OLED 유기 EL 소자의 기본 구조 Pusan National University Center of Plastic Information System

The Principle of the Operation of OLEDs ITO E Pusan National University HTL EML ETL Cathode Difference in Potential Electric Field Center of Plastic Information System

Photoluminescence와 Electroluminescence 비교 Fluorescence • Electroluminescence Phosphorescence Fluorescence • Photoluminescence Phosphorescence Pusan National University Center of Plastic Information System

Excitation and Deactivation Jablonski diagram Pusan National University Center of Plastic Information System

h+ eh+ + e- pair 25 % Singlet exciton 75 % Triplet exciton Fluorescence(~25%) Phosphorescence Emission External emission Pusan National University Center of Plastic Information System

hv Cathode Anode HTL EML HBL ETL 400 Pusan National University 500 600 Red Yellow Orange Green Ultraviolet light Blue X-rays Violet Visible light Wavelength, nanometers (nm) Infrared light Radio waves 700 Center of Plastic Information System

Energy Levels of Metals and Others Sample HOMO (IP, e. V) LUMO (Electron affinity, e. V) Band Gap (e. V) 5. 14 Alq 3 5. 8 3. 1 2. 7 ITO 4. 7 PBD 6. 2 2. 6 3. 6 Zn 4. 33 4. 3 5. 1 (4. 96) 3. 0 (2. 73) Al MEHPPV 2. 1 (2. 23) Mg 3. 7 CN-PPV 5. 7 3. 5 2. 2 Mg. Ag 3. 6 PPV 5. 1 (5. 4) 2. 6 (2. 1) 2. 5 Ca 2. 9 PVK 5. 4 (6. 1) 1. 9 3. 5 Li 2. 32, 3. 1 TPD 5. 5 2. 3 3. 2 Sample Work Function (e. V) Au Pusan National University Center of Plastic Information System

Emitting Materials Pusan National University Center of Plastic Information System

고분자 OLED Pusan National University Center of Plastic Information System

Light-Emitting Polymers for PLEDs Poly(fluorene)s Poly(p-phenylenevinylene)s Poly(thiophene)s Buffer Layer Pusan National University Center of Plastic Information System

Ligand Centered 3 - * Transition 1 * singlet excited state (계간전이) triplet excited state 3 형광 emitting * 인광 emitting (ground state) ▶ Ligand centered 3 p-p* transition 에너지를 결정하는 주요 요인은 3 p* 의 에너지이며, 이는 conjugation 늘어남에 따라 낮아지는 즉 red-shift 하는 경향을 보인다. Pusan National University Center of Plastic Information System