Light-emitting element, light-emitting device, electronic device, and lighting device
Assignee
Semiconductor Energy Laboratory Co., Ltd.
Inventors
Satoshi Seo, Tsunenori Suzuki, Yusuke Takita, Naoaki Hashimoto
Abstract
A novel light-emitting element is provided. A light-emitting element with a long lifetime is provided. A light-emitting element with high emission efficiency is provided. In the light-emitting element, an EL layer includes a hole-injection layer, a first hole-transport layer, a second hole-transport layer, a third hole-transport layer, a light-emitting layer, a first electron-transport layer, and a second electron-transport layer in this order; the hole-injection layer includes an organic acceptor; the LUMO level of the host material is higher than that of the first electron-transport layer; the LUMO level of the second electron-transport layer is higher than that of the first electron-transport layer; the host material is a substance including a condensed aromatic ring skeleton; and the first and second electron-transport layers each include a substance having a heteroaromatic ring skeleton.
CPC Classifications
Filing Date
2023-01-30
Application No.
18102914
Claims
12