AU Optronics (AUO) Corp demonstrated a 4-inch OLED panel whose display part can be bent with a curvature radius of 10mm at FPD International 2011, which took place from Oct 26 to 28, 2011, in Yokohama, Japan.
It has a thickness of only 0.3mm and a pixel count of 240 x 320. AUO formed a resin substrate on a glass substrate and formed driver elements and OLED elements on it. Then, the glass substrate and the resin substrate were separated. As a result, the thickness of 0.3mm was realized.
AUO used amorphous IGZO (In-Ga-Zn-O) TFTs as driver elements. They were formed in a vacuum process at a temperature of 220°C or lower. Two transistors and one capacitor are used for each TFT pixel. The company did not disclose the type of the resin substrate or the structure of the TFT.
The structure of the OLED element is the bottom emission type, which extracts light from the TFT substrate. Red, green and blue low molecular-type luminescent materials were formed by using a vapor deposition technology. And a thin film was used to package the OLED elements.