A method of vaporizing material at a uniform rate for forming a layer on a substrate includes feeding a column of vaporizable material from a temperature controlled region maintained below the vaporizable material's effective vaporization temperature to a source of vaporization energy, wherein the volume...http://www.google.com/patents/US7989021?utm_source=gb-gplus-sharePatent US7989021 - Vaporizing material at a uniform rate
