Patternable Semi‐Transparent Cathode using Thermal Evaporation for OLED Display Applications

• Published in: Advanced electronic materials Vol. 7; no. 4
• Main Authors: Jung, Sang Won, Kim, Kwan‐Soo, Park, Han‐un, Lampande, Raju, Kim, Seong Keun, Kim, Jae‐Hyeon, Han, Chang‐Wook, Choi, Hyun‐Chul, Kwon, Jang Hyuk
• Format: Journal Article
• Language: English
• Published: 01-04-2021
• Subjects: low temperature processing; patternable cathodes; semi‐transparent cathodes; Zn:Mg
• ISSN: 2199-160X; 2199-160X
• DOI: 10.1002/aelm.202001101

A new patternable semi‐transparent metal cathode, Zn:Mg (4:1 and 10:1) using the thermal evaporation process for organic light‐emitting diode (OLED) display applications is reported. A new Zn:Mg alloy film shows good surface morphology and almost no temperature effect on the shadow mask. The Zn:Mg layer with ratio of 4:1 and 10:1 shows sheet resistance of 33.2 and 39.2 Ω ϒ−1, respectively, at the thickness of 12 nm. The fabricated green top‐emitting OLED (TEOLED) with Zn:Mg cathode shows current efficiency of 79.3 cd A−1 and a color coordinates of (0.166, 0.755). These results show the possibility of high‐quality cathode patterning for various OLED display and sensor applications.
This study reports a new patternable Zn:Mg cathode using low temperature evaporation for organic light‐emitting diode (OLED) display applications. This electrode shows stable morphology and good optical properties. Furthermore, it shows no change of mask temperature. A green TEOLED with this new electrode shows current efficiency of 79.3 cd A−1 and color coordinates of (0.166, 0.755).