Chemical deposition of Cu2O films with ultra-low resistivity: correlation with the defect landscape
Abderrahime Sekkat, Maciej Oskar Liedke, Việt Hương Nguyễn, Maik Butterling, Federico Baiutti, Juan de Dios Sirvent, Matthieu Weber, Laëtitia Rapenne, Daniel Bellet, Guy Chichignoud, Anne Kaminski‐Cachopo, Eric Hirschmann, A. Wagner, David Muñoz‐Rojas
Abstract
Abstract Cuprous oxide (Cu 2 O) is a promising p-type semiconductor material for many applications. So far, the lowest resistivity values are obtained for films deposited by physical methods and/or at high temperatures (~1000 °C), limiting their mass integration. Here, Cu 2 O thin films with ultra-low resistivity values of 0.4 Ω.cm were deposited at only 260 °C by atmospheric pressure spatial atomic layer deposition, a scalable chemical approach. The carrier concentration (7.10 14 −2.10 18 cm −3 ), mobility (1–86 cm 2 /V.s), and optical bandgap (2.2–2.48 eV) are easily tuned by adjusting the fraction of oxygen used during deposition. The properties of the films are correlated to the defect landscape, as revealed by a combination of techniques (positron annihilation spectroscopy (PAS), Raman spectroscopy and photoluminescence). Our results reveal the existence of large complex defects and the decrease of the overall defect concentration in the films with increasing oxygen fraction used during deposition.