Mackus Adriaan J M, Merkx Marc J M, Kessels Wilhelmus M M
Department of Applied Physics, Eindhoven University of Technology, P. O. Box 513, 5600 MB Eindhoven, The Netherlands.
Chem Mater. 2019 Jan 8;31(1):2-12. doi: 10.1021/acs.chemmater.8b03454. Epub 2018 Dec 19.
Bottom-up nanofabrication by area-selective atomic layer deposition (ALD) is currently gaining momentum in semiconductor processing, because of the increasing need for eliminating the edge placement errors of top-down processing. Moreover, area-selective ALD offers new opportunities in many other areas such as the synthesis of catalysts with atomic-level control. This Perspective provides an overview of the current developments in the field of area-selective ALD, discusses the challenge of achieving a high selectivity, and provides a vision for how area-selective ALD processes can be improved. A general cause for the loss of selectivity during deposition is that the character of surfaces on which no deposition should take place changes when it is exposed to the ALD chemistry. A solution is to implement correction steps during ALD involving for example surface functionalization or selective etching. This leads to the development of advanced ALD cycles by combining conventional two-step ALD cycles with correction steps in multistep cycle and/or supercycle recipes.
通过区域选择性原子层沉积（ALD）进行的自下而上的纳米制造目前在半导体加工领域正蓬勃发展，这是因为消除自上而下加工中的边缘放置误差的需求日益增加。此外，区域选择性ALD在许多其他领域提供了新机遇，例如在具有原子级控制的催化剂合成方面。本观点文章概述了区域选择性ALD领域的当前进展，讨论了实现高选择性所面临的挑战，并对如何改进区域选择性ALD工艺提出了展望。沉积过程中选择性丧失的一个普遍原因是，不应发生沉积的表面在暴露于ALD化学过程时其性质会发生变化。一种解决方案是在ALD过程中实施校正步骤，例如涉及表面功能化或选择性蚀刻。这导致了先进ALD循环的发展，即将传统的两步ALD循环与多步循环和/或超循环配方中的校正步骤相结合。
