Ultra-fine grain size tantalum sputtering targets with improved voltage performance and methods thereby

Abstract

A method of making a tantalum sputtering target providing the steps of: a) providing a tantalum ingot; b) forging and annealing the tantalum ingot to provide a grain refined tantalum billet; and c) processing the grain refined tantalum billet to produce a tantalum sputtering target with a reduced grain size and a reduced grain size standard deviation. A tantalum sputtering targeting having a purity of at least 99.9%, a grain size of about 30 μm or less, and a grain size standard deviation of about 20 μm or less. A sputtering target manufactured in accordance with this invention will have a more consistent and stable voltage performance throughout target life, compared to prior methods with a larger grain size and grain size deviation. A more consistent and stable voltage performance leads to improved film uniformity.

Dependencies are inferred from the claim text.