eprintid: 10099692 rev_number: 15 eprint_status: archive userid: 608 dir: disk0/10/09/96/92 datestamp: 2020-06-04 10:00:05 lastmod: 2021-10-18 22:45:07 status_changed: 2020-06-04 10:00:05 type: article metadata_visibility: show creators_name: Mudiyanselage, K creators_name: Nadeem, MA creators_name: Raboui, HA creators_name: Idriss, H title: Growth, characterization, and stability testing of epitaxial MgO (100) on GaAs (100) ispublished: pub divisions: UCL divisions: B04 divisions: C06 divisions: F56 keywords: Epitaxial MgO (100) films, GaAs (100), Flake-like Mg(OH)2 structures, MgO (100) grown on GaAs (100), Lateral misfit between MgO (100) and GaAs (100) note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. abstract: Epitaxial MgO (100) films have been grown on GaAs (100) by evaporation of Mg in the presence of 5 × 10−6 Torr of oxygen. Prior to the growth of MgO, the GaAs (100) substrate was cleaned by Ar ion sputtering and annealing. MgO (100) on GaAs (100) was in situ characterized with Auger electron spectroscopy (AES), and ex situ by scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and energy–dispersive X–ray spectroscopy (EDX). X-ray diffraction patterns indicated that the MgO film has grown predominantly in the cubic phase with the (100) plane parallel to the GaAs (100) substrate. HRTEM results have confirmed the epitaxial growth of MgO with MgO (100)[001]║ GaAs (100)[001]. Despite the high lattice misfit, the epitaxial MgO (100) is grown on GaAs (100) due to the 4: 3 relationship (4 aMgO: 3 aGaAs) between MgO (100) and GaAs (100). The formation of a 4:3 superstructure reduces the lateral misfit between MgO (100) and GaAs (100) to ≈0.65%. To test the potential of MgO as a protection layer for III-V semiconductor based photo-electro catalytic devices for water splitting in alkaline media the reaction of MgO films with H2O and NaOH was investigated. Flake-like Mg(OH)2 structures appear to have formed on top of the MgO films treated with NaOH. date: 2020-09 date_type: published publisher: Elsevier BV official_url: https://doi.org/10.1016/j.susc.2020.121625 oa_status: green full_text_type: other language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 1787277 doi: 10.1016/j.susc.2020.121625 lyricists_name: Idriss, Hicham lyricists_id: HIDRI57 actors_name: Allington-Smith, Dominic actors_id: DAALL44 actors_role: owner full_text_status: public publication: Surface Science volume: 699 article_number: 121625 citation: Mudiyanselage, K; Nadeem, MA; Raboui, HA; Idriss, H; (2020) Growth, characterization, and stability testing of epitaxial MgO (100) on GaAs (100). Surface Science , 699 , Article 121625. 10.1016/j.susc.2020.121625 <https://doi.org/10.1016/j.susc.2020.121625>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10099692/1/Idriss_Revised%20Mudiyanselage%20et%20al%20No%20Highlights.pdf