High efficiency hybrid light-emitting diode

US8309947B2 · kind B2 · utility

Assignee

• COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES · FR

Inventor

• David Vaufrey · Grenoble, FR

Key dates

• Filing date: Mar 8, 2011
• Grant date: Nov 13, 2012
• Expiry date: May 11, 2031

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10K2101/10

Abstract

A hybrid LED comprising an anode, an organic hole-transport layer for transporting holes injected into the diode from said anode, a light-emitting quantum dot layer, an electron-transport layer, and a cathode for injecting electrons into said transport layer, wherein the LED also comprises, between said hole- and electron-transport layers, at least one assembly formed by a phosphorescent light-emitting layer presenting an emission spectrum that covers at least part of an absorption spectrum of said quantum dots, and by a buffer layer separating said phosphorescent layer from said quantum dot layer, the material of said or each buffer layer presenting a forbidden band greater than that of a phosphorescent element of said phosphorescent layer so as to prevent excitons diffusing towards said quantum dot layer.