Patent ID: 7238383
Filing Date: 2007-07-03
Classification: C23C,H01L

Abstract:
1. A method of making an OLED display wherein emission layer is deposited using a compacted cylindrical pellet of organic materials comprising: (a) providing a compacted cylindrical pellet comprising (i) organic materials comprising one host and one dopant and (ii) a thermally insulating inorganic material that sublimes at a temperature higher than the temperature at which the organic materials sublime; (b) placing the compacted cylindrical pellet inside a receptacle disposed in a physical vapor deposition chamber; (c) positioning a substrate of a partially formed OLED device in the physical deposition chamber in a spaced relationship with respect to the receptacle; (d) evacuating the chamber to a reduced pressure; (e) applying heat to a surface of the compacted cylindrical pellet of organic material by electrically energizing a heater disposed in an evaporation source to cause at least a portion to sublime to provide a mixture of vapors of the organic materials including the host and the dopant(s) to form an emission layer on the substrate; and (f) rotating the compacted cylindrical pellet in order to expose a fresh portion of the organic materials on the pellet to the heater and discarding the non-sublimable thermally insulating inorganic material during the process of rotation.