Apparatus for deposition of composition spread alloy films: The rotatable shadow mask

作者：Fleutot Benoit; Miller James B; Gellman Andrew J^*

来源：Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films , 2012, 30(6): 061511.

DOI：10.1116/1.4766194

• electron beam deposition
• masks
• metallic thin films

Composition spread alloy films (CSAFs) are materials libraries used for high throughput investigations of multicomponent materials such as alloys, A(x)B(y)C(1-x-y). CSAFs are prepared such that the alloy film has a lateral spatial gradient in its local composition; thus, they include a set of alloy samples with a distribution of compositions that spans a continuous region of composition space (x,y). A tool based on the shadow mask concept has been developed for generating composition gradients, but modified to allow rotation of the shadow mask during CSAF deposition. The tool allows deposition of CSAFs containing up to four elements with rotatable shadow masks between each of the four electron beam evaporation sources and the deposition substrate. This allows codeposition of any combination of up to four components. In the case of the ternary A(x)B(y)C(1-x-y) CSAFs, the three components can be deposited such that the resulting CSAF spans the entire ternary alloy composition space (x = 0 -> 1, y = 0 -> 1 - x) and, furthermore, contains all three binary alloys A(x)B(1-x), A(x)C(1-x), and BxC1-x (x = 0 -> 1) and all three pure components. The innovation of the rotatable shadow masks also allows preparation of CSAFs that magnify selected regions of the composition space (x = x(min) -> x(max), y = y(min) -> 1 - x). Herein, we describe the design and performance of this new CSAF deposition tool and assess its merits and limitations with respect to other methods for CSAF preparation.

• 出版日期2012-11