Inherently Selective Atomic Layer Deposition and Applications

Abstract

The chemical approaches enabling selective atomic layer deposition (ALD) are gaining growing interest. The selective ALD has unlocked attractive avenues for the development of novel nanostructures and found its versatile applications in emerging fields beyond the semiconductor industry. In this article, the recent developments of inherently selective ALD methods are summarized. Based on precursors’ preferential adsorptions on dangling bonds, interstitials, grain boundaries, etc., single atom deposition, well aligned nanowire growth, and defect passivation can be achieved to minimize the total surface energy. By choosing the precursors with appropriate ligands, activities, steric hindrances, etc., terrace and step edge preferential selectivity can be obtained on the same material. The starting surfaces have remarkable influences on the initial nucleation stage, which are more pronounced between different materials compared to the heterogeneity regions of the same material. Thus, the inherent selectivity can be achieved or enhanced by tuning kinetic parameters including precursor partial pressure, temperature, etc. The intrinsic driving forces, challenges, and perspectives of the inherently selective ALD with accuracy and robustness for nanofabrication are discussed. It is a great expansion of the selective ALD technique for bottom up nanofabrication in various emerging application fields.