Analysis and simulation of reddish overshoot in active matrix organic light-emitting diode display with varying p-doped hole transport layer concentrations

• Published in: Organic electronics 2021-12, Vol.99, p.106328, Article 106328
• Main Authors: Lee, Jung-Min, Kang, Chang Heon, Yoo, Juhn Suk, Hwang, Han Wook, Hong, Soon kwang, Ha, Yong Min, Ju, Byeong-Kwon
• Format: Article
• Language: English
• Subjects: Active matrix organic light-emitting diode; Lateral leakage current; Overshoot; p-doped hole transport layer; SPICE simulation
• ISSN: 1566-1199; 1878-5530
• DOI: 10.1016/j.orgel.2021.106328

A typical organic light-emitting diode (OLED) display has common organic layers between adjacent pixels, which ensure ease of manufacturing process and efficiency in operation. The p-doped hole transport layer (p-HTL) has low electrical resistivity, which results in a high efficiency OLED. However, the low resistivity results in various side effects, including color crosstalk and overshoot, mainly due to lateral leakage current flowing through this layer. Furthermore, virtual reality and augmented reality devices that require extremely high pixels per inch (PPI) and superior image quality are very sensitive to lateral leakage current. In this study, we propose a passive driving panel based on RGB top emission to efficiently measure and model the lateral leakage current characteristics according to the p-HTL concentration. In addition, we constructed a 1.5-inch active matrix organic light-emitting diode panel based on the n-type low-temperature polycrystalline silicon 4T2C pixel circuit. Subsequently, we quantitatively analyzed the reddish overshoot phenomenon during the black to white image transition. This effect was reduced at p-HTL concentrations under 1%. Finally, we analyzed the overshoot mechanism through SPICE simulations and realized the optimal lateral resistance value of the common organic layer for each PPI. [Display omitted] •Passive driving OLED and AMOLED display with varying p-HTL concentration.•Effect of the lateral leakage current on the AMOLED display.•Analysis of reddish overshoot mechanism through SPICE simulations and accurate OLED modeling.•An optimal lateral resistance value for the common organic layer is proposed for each PPI.