(64b) Atomic Layer Etching of Metal with Anisotropy, Specificity and Selectivity
AIChE Annual Meeting
Monday, November 16, 2020 - 2:15pm to 2:30pm
In this talk, current work addressing the era of metals, referring to the introduction of complex metal stacks in enabling technologies, will be presented. This is a real challenge in materials integration since many of these metals are chemically inert. Metals offer superior physical properties such as high electrical and thermal conductivities â traits desirable for microelectronics integration. However, in contrast to the rapid increase in application needs, metal patterning at the nanometer scale remains largely unsolved, as many of these metals are etch-resistant. This work highlights the importance of tailoring the energy and distribution of low energy reactive ions to enable atomic layer etching, the potential of which can be fully explored to tailor the surface reactions and selectivity. This atomic layer etching process is comprised of low energy ions introducing well controlled and directional reaction front in creating the chemical contrast that is needed in the subsequent self-limiting and thermally driven reactions to achieve an anisotropic profile. The experimental results, combined with first-principle calculations, demonstrate how surface reactivity and selectivity, instead of etch rate, is the focus of realizing nanometer-level patterning on etch-resistant materials. This novel process is generalizable to realize atomic precision in removing etch-resistant materials with complex compositions or structures.