Multicolor organic light emitting devices

• Main Authors: N PAUL EDWARD BURROWS, MR. STEPHEN,ROSS FORREST, MARK EDWARD THOMPSON, DENNIS,MATTHEW MCCARTY, LINDA,SUSAN SAPOCHAK
• Format: Patent
• Language: English
• Published: 23.04.1998
• Edition: 6
• Subjects: ADHESIVES; ADVERTISING; ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICESUSING STATIC MEANS TO PRESENT VARIABLE INFORMATION; BASIC ELECTRIC ELEMENTS; CHEMISTRY; CRYPTOGRAPHY; DISPLAY; DYES; EDUCATION; ELECTRIC HEATING; ELECTRIC LIGHTING NOT OTHERWISE PROVIDED FOR; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FORELSEWHERE; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; PAINTS; PHYSICS; POLISHES; SEALS; SEMICONDUCTOR DEVICES

An organic light emitting structure comprises, in sequence, a substrate, a first electrically conductive layer, a transparent organic light emitting layer structure, a transparent electrically conductive metal layer having a work function less than 4 eV, and a second electrically conductive layer of indium tin oxide. The structure can be incorporated in a multicolor organic light emitting device employing vertically stacked layers of double heterostructure devices which are fabricated from organic compounds. The vertical stacked structure is formed on a glass base having a transparent coating of ITO or similar metal to provide a substrate. Deposited on the substrate is the vertical stacked arrangement of three double heterostructure devices, each fabricated from a suitable organic material. Stacking is implemented such that the double heterostructure with the longest wavelength is on the top of the stack. This constitutes the device emitting red light on the top with the device having the shortest wavelength, namely, the device emitting blue light, on the bottom of the stack. Located between the red and blue device structures is the green device structure. The devices are configured as stacked to provide a staircase profile whereby each device is separated from the other by a thin transparent conductive contact layer to enable light emanating from each of the devices to pass through the semitransparent contacts and through the lower device structures while further enabling each of the devices to receive a selective bias.