| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances and Discoveries in Non-equilibrium Driven Nanomaterials and Thin Films
|
| Presentation Title |
Controlling Nanoscale Eutectic Microstructures in Directionally Laser Melted Al-Cu Alloyed Thin Films |
| Author(s) |
Eli Sullivan, John Tomko, Jonathan M. Skelton, Patrick E. Hopkins, James M. Fitz-Gerald, Jerrold A. Floro |
| On-Site Speaker (Planned) |
Eli Sullivan |
| Abstract Scope |
Eutectic solidification by scanning laser melting readily creates nanostructuring in thin films. Sputter deposited Al-Cu eutectic thin films on fused silica, 500 and 200 nm thick, produced highly-regular lamellae whose spacing is controlled by the laser scan speed, where interlamellar spacing < 50 nm was achieved. Hypoeutectic films exhibit unusual structure, wherein regions of equiaxed dendrites compete with a chaotic lamellar structure. Thin films offer a unique opportunity to impose deliberate geometric modification of solidification that may offer new control over carrier transport. Shadow masking during film growth produces external shapes in the film such as strips, arcs, or circles, which modify solidification nanostructures via the boundary conditions on thermal diffusion. Even more interesting is the ability to selectively perturb the solidification front using focused-ion-beam milling of nano-hole arrays, which can create long-range, super-periodic modulation of the structure. Support of the NSF under grant DMR-1663085 is gratefully acknowledged. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |