Patent ID: 7871563
Filing Date: 2011-01-18
Classification: B22F,C23C,Y10T

Abstract:
1. A process for refurbishing a spent sputtering target to restore it to its original form comprising the steps of: receiving a spent sputtering target comprised of an un-sputtered metal of a particular composition, wherein the spent sputtering target has a non-uniform depleted region on its top surface and a back surface opposite the depleted region, identifying a desired weight that corresponds to the weight of the spent sputtering target in an original form, determining the weight of the spent sputtering target, disposing the spent sputtering target within a hot press die that has a bottom wall such that the back surface of the target abuts the bottom wall, filling only the non-uniform depleted region with a powder of the metal, the powder having a particular composition that corresponds to the particular composition of the un-sputtered metal, the filling step being performed either before or after the step of disposing the sputtering target within the hot press die, thus producing a filled sputtering target with a layer of powder and an interface between the powder and depleted region, wherein the total weight of the powder and the spent sputtering target is substantially equal to the desired weight, and applying sufficient heat and uniaxial force in a direction perpendicular to the top surface of the depleted region while maintaining the temperature below that of the melting point of the metal to ensure solid state diffusion is the only mechanism taking place during the step of applying sufficient heat and uniaxial force to hot press the filled sputtering target such that the powdered metal sinters and bonds with the un-sputtered metal during a solid state diffusion process, thus restoring the spent target to the original form by homogenizing the interface and producing a homogenous refurbished target with the same porosity and anomalous grain growth throughout the refurbished target, thereby homogenizing the interface that existed before the step of applying sufficient heat and uniaxial force.