The research on the characteristics of bilayer organic light-emitting devices

The effect of carrier mobility and functional layer on the characteristics of organic light-emitting devices(OLED) is studied theoretically. Here, our numerical results demonstrate that relative small space charge density results in the more steady behavior, which decreases near the interface, then reaches a final certain value. As r increases, and m is less than 0.10, the current density is steadily increased; when m is greater than 0.01, the current density is first increased then drop until r is greater than 0.8, at the same time the electron transport layer( ETL )is very thin, approximately 1. When m is small, increasing the thickness of the hole transport layer, a hole accumulation in the interface, so that the field strength increases, ETL increases. When r is greater than 0.8 and m less than 0.1, the effective transmission holes great influence on the device current, the maximum value of the load current may tend.