- Journal
- Materials Today Advances
- Date
- 2024.03.04
- Abstract
Under thin film deposition, when used in conjunction with the semiconductor atomic layer
deposition (ALD) method, the choice of precursor determines the properties and quality of
the thin film. Organometallic precursors such as alkaline earth metals (Sr and Ba) and group
4 transition metals (Zr and Hf) with cyclopentadienyl and tetrakis (ethylmethylamino) ligands
have recently gained attention for their stable deposition within high-temperature windows
in the ALD. The design of organometallic precursors with an ab initio molecular dynamics
(AIMD) simulations-based approach ensures high accuracy but comes with significant
computational costs. In this study, we aim to develop a machine-learning interatomic
potential (MLIP) through moment tensor potential (MTP) for fast and accurate potential
development of Sr, Ba, Zr, and Hf precursors. To establish the reliable training database for
MTP construction, we conducted AIMD simulations on each precursor across a range of
temperature settings, resulting in a variety of atomic structures. Constructed MTPs enable
efficient utilization of molecular dynamics (MD) simulations as well as calculations that
achieve an accuracy that approximates density functional theory (DFT). MTP construction
coupled with active learning ensures that the MTP for each precursor is reliable and that
databases can be expanded. High prediction accuracy is demonstrated by a mean absolute
error (MAE) of less than 0.04 eV/atom in all structures. In addition, generalization
performance is confirmed for general structures (structures with the same chemical elements
but different proportions) and is extended to cluster structures. The constructed MTP exhibits
an MAE of less than 0.15 eV/atom, even for untrained cluster structures. These results
demonstrate adequate representation and scalability as a basis for the development of MLIPs
capable of atomic simulations of organometallic precursors under various thermodynamic conditions.
- Reference
- N