Light-emitting element, light-emitting device, display device, lighting device, and electronic device

US10439156B2 · kind B2 · utility

Assignee

• Semiconductor Energy Laboratory Co., Ltd. · JP

Inventors

• Satoko Shitagaki · Yokohama, JP
• Takahiro Ishisone · Yokohama, JP
• Satoshi Seo · Yokohama, JP
• Takeyoshi WATABE · Yokohama, JP

Key dates

• Filing date: May 14, 2014
• Grant date: Oct 8, 2019
• Expiry date: May 14, 2034

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10K85/6572

Abstract

Provided is a light-emitting element which has an anode, a light-emitting layer over the anode, an electron-transport layer over and in contact with the light-emitting layer, an electron-injection layer over and in contact with the electron-transport layer, and a cathode over and in contact with the electron-injection layer. The light-emitting layer has an electron-transport property, and the electron-transport layer includes an anthracene derivative. The light-emitting layer further includes a phosphorescent substance. This device structure allows the formation of a highly efficient blue-emissive light-emitting element even though the phosphorescent substance has higher triplet energy than the anthracene derivative which directly contacts with the light-emitting layer.