Molybdenum Tubular Sputtering Targets With Uniform Grain Size And Texture - Patent 8088232

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Molybdenum Tubular Sputtering Targets With Uniform Grain Size And Texture - Patent 8088232 Powered By Docstoc
Description: OF THE INVENTION The present invention relates to forms of molybdenum, their use as sputtering targets and method of their manufacture.BACKGROUND OF THE INVENTION The sputtering technique is a film-forming technique with which a plasma is utilized to generate ions striking a sputtering target so as to result in atoms of the sputtering target depositing on a substrate as a film. The sputtering techniqueis particularly used to produce a metallic layer in various manufacturing processes used in the semiconductor and the photoelectric industries. The properties of films formed during sputtering is related to the properties of the sputtering target itselfsuch as, the size of the respective crystal grain and the formation of secondary phase with distribution characteristics. Various sputtering techniques are used in order to effect the deposition of a film over the surface of a substrate. Deposited metal films, such as metal films on a flat panel display device, can be formed by a magnetron sputtering apparatus orother sputtering techniques. The magnetron sputtering apparatus induces plasma ions of a gas to bombard a target, causing surface atoms of the target material to be ejected therefrom and to be deposited as a film or layer on the surface of a substrate. Conventionally, a sputtering source in the form of a planar disc or rectangle is used as the target, and ejected atoms travel along a line-of-sight trajectory to deposit on top of a wafer whose deposition face is parallel to the erosion face of thetarget. However, a tubular-shaped sputtering target can also be used. In this case, the plasma is external and the atoms are sputtered from the exterior of the tube. The flat substrate is slowly passed over the target. Typically, its motion ishorizontal, and in a direction at a right angle to the target axis, which is also horizontal. Thus the substrate can be gradually coated as it passes over the target. In many cases, sputtering targets, particularly those con