HIGH EFFICIENCY PHOSPHORESCENT ORGANIC LIGHT EMITTING DIODES USING SANDWICH-MIXED DOUBLE EMISSION HOSTS AND THEIR FABRICATION METHODS

摘要

PURPOSE: A phosphorescent organic light emitting diode with high efficiency using a sandwich-mixed double light emitting host is provided to secure a generation region of an exciton near the center of a light emitting layer. CONSTITUTION: A first electrode is formed on a substrate. A second electrode is formed in a position to face the first electrode. A light emitting layer is positioned between the first electrode and the second electrode. The light emitting layer is comprised of a hole transmissive light emitting host(71), a mixing light emitting host(73), and an electron transmissive light emitting host(72). The mixing light emitting host includes the mixture of the hole transmissive light emitting host and the electron transmissive light emitting host of a ratio of 3:1 or 1:3. The hole transmissive light emitting host, the mixing light emitting host, and the electron transmissive light emitting host are the fluorescent material.