Patternable Semi‐Transparent Cathode using Thermal Evaporation for OLED Display Applications
Sang Won Jung, Kwan‐Soo Kim, Han‐un Park, Raju Lampande, Seong Keun Kim, Jae‐Hyeon Kim, Chang‐Wook Han, Hyun‐Chul Choi, Jang Hyuk Kwon
Abstract
Abstract 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.