An Atomic Layer Etching (ALE)-Inspired Synthetic Protocol and Rapid Screening Process for ZnO Etching with β-Diketone Reagents

Atomic layer etching (ALE) is a top-down vapor-phase process that leads to self-limiting thinning of materials with an angstrom-level control. ALE has emerged as an attractive process for the wafer-scale fabrication of devices and materials with dimensional control on the nanoscale. The screening and optimization of molecular precursors for ALE processes are time- and resource-intensive. Herein, using ZnO and acetylacetone (Hacac) etching chemistry, we demonstrate a rapid thermogravimetric analysis (TGA) screening protocol with a series of β-diketones and validate its result by performing proof-of-concept ALE of ZnO with down-selected hexafluoroacetylacetone (Hhfac). The ALE process motivates the elaboration of a solvothermal and sonochemical protocol for the synthesis of Zn β-diketonate complexes under mild conditions and with excellent yields.