Atomistic-mesoscopic modeling of area-selective thermal atomic layer deposition

Abstract

There has been growing interest in area-selective atomic layer deposition (ASALD) with the integration of small-molecule inhibitors (SMIs) to improve the regioselectivity of thin-layer deposition on growth areas. ASALD offers an alternative solution to the challenges for the nanofabrication of transistors: difficulty of achieving self-alignment and imprecise thickness control. In this work, atomistic simulations are performed using density functional theory (DFT) and a mesoscopic model for ASALD is developed on a SiO2/Al2O3 surface based on a kinetic Monte Carlo (kMC) method, which simulates the deposition and reaction processes that take place on the surface. The ASALD process comprises the SMI, acetylacetone, for Step A, precursor, bis(diethylamino)silane (BDEAS), for Step B, and oxidant, ozone, for Step C. The simulation results comprehensively characterize the surface kinetics of ASALD implemented with steric effects that are produced by the SMI and BDEAS and are comparable to the results from experimental findings.