Forming homogeneous mixtures of organic materials for physical vapor deposition using melting

A method for forming homogeneous mixtures of powders of organic materials, which include, at least one dopant component and one host component, to provide a homogenous mixture for use in thermal physical vapor deposition to produce an organic layer on a substrate for use in an organic light-emitting device. The method includes, combining organic materials having at least one dopant component and one host component to form a mixture of organic materials and placing the mixture of organic materials in a container and sealing the container. The method further includes, heating and mixing the organic materials until they are melted, to form a homogeneous mixture of organic materials. Solidifying the homogeneous mixture of organic materials and removing the solidified homogeneous mixture of organic materials from the container.