Method for consolidating and diffusion-bonding powder metallurgy sputtering target

Abstract

Methods for manufacturing sputtering target assemblies and assemblies thereof are provided, particularly targets made of powders. Powders are adhered to a backing plate by use of a vacuum hot press, the powder preferably contacted by non-planar surfaces, and is compressed with at least about 95% density and substantially simultaneously diffusion-bonded to the backing plate.

1 . An assembly for making a sputter target comprising the steps of:
 a compression means having an upper portion surface and a lower portion surface;   a backing plate having a first and second backing plate surface, said second surface in contact with the lower portion surface of the compression means;   a powder layer having a first and second surface, said second powder layer surface in contact with the first surface of the backing plate, and said first powder layer surface in contact with the upper portion surface of the compression means, and said powder layer compressed to a density; and   wherein at least one powder layer surface is non-planar.   
     
     
         2 . The assembly of  claim 1 , wherein the first surface of the powder layer is substantially concave. 
     
     
         3 . The assembly of  claim 1 , wherein the powder comprises a material selected from a group consisting of copper-containing material and titanium-containing material. 
     
     
         4 . The assembly of  claim 1 , wherein the powder comprises a material selected from the group consisting of: copper, copper alloys, titanium and titanium alloys. 
     
     
         5 . The assembly of  claim 4 , wherein the copper alloy is selected from the group consisting of: copper-chromium; copper-titanium; copper-nickel, and combinations thereof 
     
     
         6 . The assembly of  claim 4 , wherein the titanium alloy is selected from the group consisting of: titanium-tungsten; titanium-copper; titanium-iron; titanium-nickel; titanium-aluminum; and combinations thereof. 
     
     
         7 . The assembly of  claim 1 , wherein the backing plate is made from a material selected from the group consisting of: copper, copper alloys, stainless steel, titanium, molybdenum, tungsten, and combinations thereof 
     
     
         8 . The assembly of  claim 1 , wherein the preferred powder size is from about 40 μm to about 150 μm. 
     
     
         9 . The assembly of  claim 1 , wherein at least one of the surfaces selected from the group consisting of: the surface of the upper portion of the compression means; the first surface of the backing plate; the second surface of the backing plate; the surface of the lower portion of the compression means, are non-planar. 
     
     
         10 . The assembly of  claim 1 , wherein the first and second surfaces of the backing plate are non-planar. 
     
     
         11 . The assembly of  claim 1 , wherein the surface of the upper portion surface of the compression means is non-planar. 
     
     
         12 . The assembly of  claim 1 , wherein the at least one surface of the backing plate is roughened with a means having a grit measure of from about 100 μin to about 300 μin Ra. 
     
     
         13 . The assembly of  claim 1 , wherein the compression means is a vacuum hot press. 
     
     
         14 . A sputter target made according to a process comprising the steps of:
 providing a powder layer having a first and second surface;   providing a backing plate having a first and second surface;   providing a compression means having an upper portion surface and a lower portion surface;   positioning the first surface of the backing plate against the lower portion surface of the compression means;   positioning the first surface of the powder layer against the second surface of the backing plate;   positioning the upper portion surface of the compression means against the second surface of the powder layer to a non-planar orientation, wherein the surface of the upper portion of the compression means is convex;   compressing the powder and backing plate to press the powder to a density of at least about 95%;   diffusion-bonding the powder to the backing plate to achieve a target assembly; and   controlling the target assembly to be warped toward a direction opposite to the second surface of the backing plate during cooling, whereby the target assembly attains a planar orientation.   
     
     
         15 . A sputter target made according to a process comprising the steps of:
 providing a powder layer having a first and second surface;   providing a backing plate having a first and second surface;   providing a compression means having an upper portion surface and a lower portion surface;   positioning the first surface of the backing plate against the lower portion surface of the compression means;   positioning the first surface of the powder layer against the second surface of the backing plate;   positioning the upper portion surface of the compression means against the second surface of the powder layer to a non-planar orientation;   compressing the arrangement to press the powder to a density of at least about 95%;   diffusion-bonding the powder to the backing plate to achieve a target assembly; and wherein the surface of the upper portion of the compression means is convex and the second surface of the backing plate is concave; and   controlling the target assembly to be warped toward a direction opposite to the second surface of the backing plate during cooling, whereby the target assembly attains a planar orientation.