Low-temperature, high-throughput spatial atomic layer deposition of NiOx nanocrystalline thin films from [Ni(ipki)2]

Year: 2025

Type: article

Abstract: Spatial atomic layer deposition (SALD) is a recent ALD variant enabling much faster deposition rates, even at atmospheric pressure, making it ideal for scalable, low-cost devices. NiO x , a transparent p-type oxide, is widely used in emerging technologies like perovskite solar cells. However, no suitable SALD process for NiO thin films has been reported so far. In this work, we present the deposition of nanocrystalline NiO x thin films via SALD using a recent Ni precursor not yet explored for the ALD of NiO, namely, bis(4-(isopropylamino)pent-3en-2-onato)nickel(II) or [Ni( i pki) 2 ]. O 2 has been used as coreactant, with higher deposition rates being achieved if H 2 O is added to the O 2 flow. A narrow ALD window has been obtained between 230 °C and 250 °C, where a GPC of 0.023 nm is observed. This corresponds to a deposition rate of 1.4 nm/min, which is 2 to 10 times faster than the rates reported for conventional ALD of NiO thin films. Remarkably, the growth onset of NiO x starts around only 170 °C. The transmittance of the films reaches nearly 97 % in the visible for 55 nm thick films. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies revealed a high homogeneity of the films. X-ray diffraction (XRD), Raman spectroscopy and X-ray absorption spectroscopy (XAS) studies confirm the presence of a cubic NiO x crystalline phase. Finally, NiO x films have been deposited on Ag nanowire networks, demonstrating the possibility of depositing homogeneous and conformal coatings with this new process.

Source: Applied Surface Science Advances

DOI: 10.1016/j.apsadv.2025.100836

Authors: Samuel Porcar, Marcel Schmickler, Hayri Okcu, Jorit Obenlüneschloß, Stefano d’Ercole, Laura Cervera- Gabalda, Itziar Galarreta-Rodriguez, Juan Rubio-Zuazo, Jaime Gonzalez Cuadra, Abderahim Lahlahi, Diego Fraga, Camilo Sanchez-Velasquez, Daniel Bellet, Thomas Fix, Juan B. Carda, Anjana Devi, David Muñoz-Rojas

Institutions: Universitat Jaume I, Leibniz Institute for Solid State and Materials Research, Ruhr University Bochum, Institut polytechnique de Grenoble, Centre National de la Recherche Scientifique, Laboratoire des Matériaux et du Génie Physique, Centre de Radiofréquences, Optique et Micro-nanoélectronique des Alpes, Université Savoie Mont Blanc, European Synchrotron Radiation Facility, Instituto de Ciencia de Materiales de Madrid, Laboratoire des Sciences de l'Ingénieur, de l'Informatique et de l'Imagerie, Université de Strasbourg, Fraunhofer Institute for Microelectronic Circuits and Systems, Technische Universität Dresden

Language: English

Topic: Semiconductor materials and devices

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,350

Funders: Ministerio de Ciencia, Innovación y Universidades, European Commission, Deutsche Forschungsgemeinschaft, Agence Nationale de la Recherche, Universitat Jaume I, Ministerio de Ciencia e Innovación, Consejo Superior de Investigaciones Científicas, Agencia Estatal de Investigación, European Social Fund, Instituto Valenciano de Competitividad Empresarial

OpenAlex ID: W4413972724