3.4L: Late‐News Paper : Advanced ELA for Large‐Sized AMOLED Displays

Abstract

Abstract This paper presents an Advanced Excimer Laser Annealing (AELA) process for large‐sized OLED displays. Achieving good uniformity and performance characteristics of LTPS TFTs using cost‐effective processes are important issues for the production of OLED displays. The AELA uses a conventional ELA system, XeCl laser, large optics and positioning stage, with improved processes and existing technology such as a selective crystallization function. The selective crystallization function of the AELA process has been optimized to obtain uniform microstructure of the crystallized Si films at the TFTs and interconnection region. Specifically, the 7/20 (W/L) TFTs via AELA processed Si films have mobility of 73.81 cm 2 /V‐sec, threshold voltage of −2.07 V and sub‐threshold swing of 0.40 V/dec. 55″ FHD OLED displays have been fabricated using the AELA process. The advantages and challenges of AELA technology will be further discussed.