P‐6.10: LTPS‐TFT Process for OLED and some issues generated from the manufacturing

AMOLED (Active‐matrix organic light emitting diode) is a new display technology used in flat panel display which has wider color gamut, higher contrast ratio, lower consumption than LCD and can achieve flexible display. However, LTPS (Low Temperature Poly‐Silicon)‐TFT (Thin Film Transistor), is now a highlight of Active Matrix Driving. As a current source, in order to drive it, there needs more TFTs and higher driven current for OLED. Compared with the traditional a‐Si TFT, LTPS‐TFT possesses the high mobility (≈100 cm 2 /V · s) and low off current poly‐silicon's character which is known as being high resolution ratio, quick reacting, wide aperture ratio and high integration. In this paper, we will discuss the common process of LTPS which is made in a relatively low temperature condition. Then we will talk about some display issues caused by LTPS process, such as mura, hysteresis and light spot, e.t.