A Process for Topographically Selective Deposition on 3D Nanostructures by Ion Implantation

Area-selective atomic layer deposition (AS-ALD) is attracting increasing interest because of its ability to enable both continued dimensional scaling and accurate pattern placement for next-generation nanoelectronics. Here we report a strategy for depositing material onto three-dimensional (3D) nanostructures with topographic selectivity using an ALD process with the aid of an ultrathin hydrophobic surface layer. Using ion implantation of fluorocarbons (CFx), a hydrophobic interfacial layer is formed, which in turn causes significant retardation of nucleation during ALD. We demonstrate the process for Pt ALD on both blanket and 2D patterned substrates. We extend the process to 3D structures, demonstrating that this method can achieve selective anisotropic deposition, selectively inhibiting Pt deposition on deactivated horizontal regions while ensuring that only vertical surfaces are decorated during ALD. The efficacy of the approach for metal oxide ALD also shows promise, though further optimization of the implantation conditions is required. The present work advances practical applications that require area-selective coating of surfaces in a variety of 3D nanostructures according to their topographical orientation.This work was supported by the Department of Energy under Award Number DE-SC0004782 (W.-H.K. and S.F.B.). F.S.M.H. was supported by the Kodak Graduate Fellowship. A.J.M.M. was supported by The Netherlands Organization for Scientific Research (NWO-Rubicon 680-50-1309). J.S. and D.B.-S. were supported by National Science Foundation Graduate Research Fellowships under Grant No. DGE-114747. Portions of this research were carried out at the Stanford Synchrotron Radiation Lightsource, a Directorate of SLAC National Accelerator Laboratory and an Office of Science User Facility operated for the U.S. Department of Energy Office of Science by Stanford University. Part of this work was performed at the Stanford Nano Shared Facilities (SNSF)