Characterizing Self-Assembled Monolayer Breakdown in Area-Selective Atomic Layer Deposition.

Autor: Liu TL; Department of Materials Science and Engineering, Stanford University, 496 Lomita Mall, Stanford, California 94305, United States., Zeng L; Department of Chemical Engineering, Stanford University, 443 Via Ortega, Stanford, California 94305, United States., Nardi KL; Lam Research Corporation, 4650 Cushing Parkway, Fremont, California 94538, United States., Hausmann DM; Lam Research Corporation, 4650 Cushing Parkway, Fremont, California 94538, United States., Bent SF; Department of Materials Science and Engineering, Stanford University, 496 Lomita Mall, Stanford, California 94305, United States.; Department of Chemical Engineering, Stanford University, 443 Via Ortega, Stanford, California 94305, United States.
Jazyk: angličtina
Zdroj: Langmuir : the ACS journal of surfaces and colloids [Langmuir] 2021 Oct 05; Vol. 37 (39), pp. 11637-11645. Date of Electronic Publication: 2021 Sep 22.
DOI: 10.1021/acs.langmuir.1c02211
Abstrakt: To enable area-selective atomic layer deposition (AS-ALD), self-assembled monolayers (SAMs) have been used as the surface inhibitor to block a variety of ALD processes. The integrity of the SAM throughout the ALD process is critical to AS-ALD. Despite the demonstrated effectiveness of inhibition by SAMs, nucleation during ALD eventually occurs on SAM-protected surfaces, but its impact on SAM structures is still not fully understood. In this study, we chose the octadecyltrichlorosilane (ODTS) SAM as a model system to investigate the evolution of crystallinity and structure of SAMs before and after ALD. The breakdown behavior of SAMs when exposed to ZnO and Al 2 O 3 ALD was systematically studied by combining synchrotron X-ray techniques and electron microscopy. We show that the crystallinity and structure of ODTS SAMs grown on Si substrates remain intact until a significant amount of material deposition takes place. In addition, the undesired ALD materials that grow on ODTS SAMs present contrasting morphologies: dispersed nanoparticles for ZnO while relatively continuous film for Al 2 O 3 . Lastly, substrate dependency was explored by comparing a Si substrate to single-crystal sapphire. Similar results in the evolution of SAM crystallinity and formation of ALD nuclei on top of SAM are observed in the ODTS-sapphire system. This study provides an in-depth view of the influence of ALD processes on the SAM structure and the nucleation behavior of ALD on SAM-protected surfaces.
Databáze: MEDLINE