Non-blocked phosphorescent OLEDs
First Claim
Patent Images
1. A device comprising:
- an anode and a cathode;
an emissive layer disposed between and electrically connected to the anode and the cathode, the emissive layer comprising an organic host and an organic dopant;
an organic hole transport layer between the anode and the emissive layer;
an organic electron transport layer between the cathode and the emissive layer,wherein said electron transport layer is a single layer and is the only layer between the cathode and the emissive layer,the HOMO level of the organic host is no more than 0.8 eV below the HOMO level of the hole transport layer,the LUMO level of the organic host is no more than 0.4 eV above the LUMO level of the electron transport layer, andthe HOMO level of the electron transport layer is no more than 0.4 eV below the HOMO level of the host,the HOMO and LUMO levels being calculated by density functional calculation,wherein the device has an external quantum efficiency of over 9.2% at 500 cd/m2 and up to about 30%.
0 Assignments
0 Petitions
Accused Products
Abstract
An organic light emitting diode (OLED) architecture in which efficient operation is achieved without requiring a blocking layer by locating the recombination zone close to the hole transport side of the emissive layer. Aryl-based hosts and Ir-based dopants with suitable concentrations result in an efficient phosphorescent OLED structure. Previously, blocking layer utilization in phosphorescent OLED architectures was considered essential to avoid exciton and hole leakage from the emissive layer, and thus keep the recombination zone inside the emissive layer to provide high device efficiency and a pure emission spectrum.
-
Citations
25 Claims
-
1. A device comprising:
-
an anode and a cathode; an emissive layer disposed between and electrically connected to the anode and the cathode, the emissive layer comprising an organic host and an organic dopant; an organic hole transport layer between the anode and the emissive layer; an organic electron transport layer between the cathode and the emissive layer, wherein said electron transport layer is a single layer and is the only layer between the cathode and the emissive layer, the HOMO level of the organic host is no more than 0.8 eV below the HOMO level of the hole transport layer, the LUMO level of the organic host is no more than 0.4 eV above the LUMO level of the electron transport layer, and the HOMO level of the electron transport layer is no more than 0.4 eV below the HOMO level of the host, the HOMO and LUMO levels being calculated by density functional calculation, wherein the device has an external quantum efficiency of over 9.2% at 500 cd/m2 and up to about 30%. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A device comprising:
-
an anode and a cathode; an emissive layer disposed between and electrically connected to the anode and the cathode, the emissive layer comprising an organic host and an organic dopant; an organic hole transport layer between the anode and the emissive layer; an organic electron transport layer between the cathode and the emissive layer, wherein said electron transport layer is a single layer and is the only layer between the cathode and the emissive layer, the HOMO level of the organic host is no more than 0.8 eV below the HOMO level of the hole transport layer, the LUMO level of the organic host is no more than 0.4 eV above the LUMO level of the electron transport layer, and the HOMO level of the electron transport layer is no more than 0.4 eV below the HOMO level of the host, the HOMO and LUMO levels being calculated by density functional calculation, the organic dopant is a phosphorescent dopant having a triplet energy corresponding to a peak emission wavelength of less than 600 nm, and the host comprises a fused-aryl ring compound, wherein the device has an external quantum efficiency of over 9.2% at 500 cd/m2 and up to about 30%. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. A device comprising:
-
an anode and a cathode; an emissive layer disposed between and electrically connected to the anode and the cathode, the emissive layer comprising an organic host and an organic dopant; an organic hole transport layer between the anode and the emissive layer; an organic electron transport layer between the cathode and the emissive layer, wherein said electron transport layer is a single layer and is the only layer between the cathode and the emissive layer, the HOMO level of the organic host is no more than 0.8 eV below the HOMO level of the hole transport layer, the LUMO level of the organic host is no more than 0.4 eV above the LUMO level of the electron transport layer, and the HOMO level of the electron transport layer is no more than 0.4 eV below the HOMO level of the host, the HOMO and LUMO levels being calculated by density functional calculation, the organic dopant is a phosphorescent dopant having a triplet energy corresponding to a peak emission wavelength of less than 600 nm, and the device has an external quantum efficiency of over 9.2% at 500 cd/m2 and up to about 30%. - View Dependent Claims (20, 21, 22, 23, 24, 25)
-
Specification