• Fernandes, José Ramiro Afonso
• Fernandes, Lisete
• Ait Bassou, Abderrazzak
• Tavares, Pedro
• Figueiras, Fábio Gabriel

Abstract

<jats:p>In this work, we investigated the MOCVD conditions to synthesize thin films with the hexagonal P63cm h-LuMnO3 phase as a potential low-band gap ferroelectric material. The main parameters investigated were the ratio of organometallic starting materials, substrate temperature, and annealing effect. Two different substrates were used in the study: fused silica (SiO2) glass and platinized silicon (Pt(100)). In order to investigate the thermodynamic stability and quality of the developed phases, a detailed analysis of the crystal structure, microstructure, morphology, and roughness of the films was performed by X-ray diffractometer, scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), Raman spectroscopy, and piezoelectric force microscopy (PFM). Molar compositions in the film within 0.93 &lt; |Lu|/|Mn| &lt; 1.33 were found to be suitable for obtaining a single-phase h-LuMnO3. The best films were obtained by depositions at 700 °C, followed by thermal treatments at 800 °C for long periods of up to 12 h. These films exhibited a highly crystalline hexagonal single phase with a relatively narrow direct band gap, around 1.5 eV, which is within the expected values for the h-LuMnO3 system.</jats:p>

Topics

• Deposition
• impedance spectroscopy
• microstructure
• phase
• scanning electron microscopy
• thin film
• glass
• glass
• Silicon
• annealing
• Energy-dispersive X-ray spectroscopy
• Raman spectroscopy
• spectrometry
• organometallic