ALUMINUM ALLOYS AND ARTICLES WITH HIGH UNIFORMITY AND ELEMENTAL CONTENT
Disclosed herein are aluminum alloys with scandium as the alloying element. The alloys have a high scandium content, as measured by atomic percentage, and are highly uniform, as described herein. Methods of forming articles from these alloys are also disclosed, such articles including sputtering targets that can be used to form thin films containing high amounts of scandium.
1 . A sputtering target formed from an alloy comprising scandium (Sc) and aluminum (Al), wherein the scandium is uniformly distributed across a surface of the sputtering target, as indicated by a difference of at most +/−0.5 wt % scandium over an entire radius of the surface in both a horizontal direction and a vertical direction.
2 . The sputtering target of claim 1 , wherein the alloy contains from 12 at % up to 50 at % scandium (Sc) and remainder aluminum (Al).
3 . The sputtering target of claim 2 , wherein the sputtering target contains less than 400 ppm of oxygen.
4 . A sputtering target formed from an alloy comprising from greater than 10 at % up to 50 at % scandium (Sc) and remainder aluminum (Al), wherein the scandium is uniformly distributed across a surface of the sputtering target, as indicated by a difference of at most +/−0.5 wt % scandium over an entire radius of the surface in both a horizontal direction and a vertical direction.
5 . The sputtering target of claim 4 , wherein the alloy contains from 12 at % to 17 at % scandium.
6 . The sputtering target of claim 5 , wherein the alloy is in the form of intermetallic Al—Sc grains in a metallic Al matrix.
7 . The sputtering target of claim 6 , wherein a cross-sectional area contains from 40% to 68% of the intermetallic Al—Sc grains.
8 . The sputtering target of claim 6 , wherein the intermetallic Al—Sc grains have an average particle size of below 100 microns.
9 . The sputtering target of claim 6 , wherein the intermetallic Al—Sc grains are uniformly distributed through a thickness of the sputtering target.
10 . The sputtering target of claim 4 , wherein the sputtering target contains less than 400 ppm of oxygen.
11 . The sputtering target of claim 4 , wherein the alloy contains from 17 at % to less than 25 at % scandium and remainder aluminum (Al).
12 . The sputtering target of claim 11 , wherein the alloy is in the form of an intermetallic Al—Sc phase in a metallic Al matrix.
13 . The sputtering target of claim 12 , wherein a cross-sectional area contains from 68% to less than 100% of the intermetallic Al—Sc phase.
14 . The sputtering target of claim 12 , wherein the intermetallic Al—Sc phase has an average particle size of below 100 microns.
15 . The sputtering target of claim 12 , wherein the intermetallic Al—Sc phase is uniformly distributed through a thickness of the sputtering target.
16 . The sputtering target of claim 11 , wherein the sputtering target contains less than 400 ppm of oxygen.
17 . The sputtering target of claim 4 , wherein the alloy contains from 25 at % to less than 33.3 at % scandium and remainder aluminum (Al), wherein the alloy is in the form of one or two intermetallic Al—Sc phases.
18 . The sputtering target of claim 17 , wherein the one or two intermetallic Al—Sc phases have an average particle size of below 300 microns, or below 100 microns.
19 . The sputtering target of claim 17 , wherein the one or two intermetallic Al—Sc phases are uniformly distributed across a surface of the sputtering target and through a thickness of the sputtering target.
20 . The sputtering target of claim 17 , wherein the sputtering target contains less than 400 ppm of oxygen.
21 . The sputtering target of claim 4 , wherein the alloy contains from 33.3 at % to 50 at % scandium and remainder aluminum (Al), wherein the alloy is in the form of one or two intermetallic Al—Sc phases.
22 . The sputtering target of claim 21 , wherein the one or two intermetallic Al—Sc phases have an average particle size of below 300 microns, or below 100 microns.
23 . The sputtering target of claim 21 , wherein the one or two intermetallic Al—Sc phases are uniformly distributed across a surface of the sputtering target and through a thickness of the sputtering target.
24 . The sputtering target of claim 21 , wherein the sputtering target contains less than 400 ppm of oxygen.
25 . A sputtering target formed from an alloy comprising greater than 10 at % scandium (Sc) and remainder aluminum (Al), wherein the scandium is uniformly distributed across a surface of the sputtering target, as indicated by a difference of at most +/−0.5 wt % scandium over an entire radius of the surface in both a horizontal direction and a vertical direction, and wherein the sputtering target contains less than 300 ppm of oxygen.
26 . The sputtering target of claim 25 , wherein the alloy contains from 12 at % to 50 at % scandium.
27 . A thin film formed by bombarding the sputtering target of claim 1 with ions to deposit material onto a substrate.