Phase Change Materials are essentially solid materials at room temperature that melt at a specified operating temperature to form intimate contact on the mating surface and therefore, significantly, reduce, thermal resistance. These materials are generally composed of a mixture of organic binders, thermally conductive fillers and an optional substrate (such as aluminum or polyimide) to give additional functionality and ease of handling. The phase change temperature generally occurs at 50 degrees Celsius to 70 degrees Celsius and this is chosen so that the material will flow when the device is initially powered up but will not flow during transport and storage. Generally, PCM materials have been traditionally used as a replacement for thermal grease which can be messy in a production environment and has also been shown to exhibit detrimental properties such as pump out, migration and poor surface wetting.