
Raman spectroscopy study of Ga-doped ZnO ceramics: An estimative of the structural disorder degree
2021; Elsevier BV; Volume: 606; Linguagem: Inglês
10.1016/j.physb.2020.412726
ISSN1873-2135
AutoresGabriela Gomes Miranda, Raphael Lucas de Sousa e Silva, Hermínia Veridiana dos Santos Pessoni, A. Franco,
Tópico(s)Ga2O3 and related materials
ResumoThe structural disorder degree of Ga-doped ZnO (Zn1−xGaxO, with x=0.005, 0.01, 0.02, and 0.03) ceramics was investigated by means of Raman spectroscopy analyzes at room temperature. The Raman spectra for Ga-doped ZnO samples exhibits both activated Raman modes for wurtzite and spinel structures. The asymmetry parameter, line-width, and Raman shift could be fitted to the Breit-Wagner-Fano (BWF) function and the structural disorder degree in the wurtzite structure were analyzed by spatial phonon confinement model (PCM). For Raman E2high mode, the correlation length, L and defect concentration, N were found to be 2.72, 2.62, 2.56, and 2.41 nm and 1.19×1019, 1.33×1019, 1.21×1019, and 1.70×1019cm−3 for x=0.005, 0.01, 0.02, and 0.03 samples, respectively. Additional Raman modes were detected in Ga-doped ZnO (x≥0.01) spectra that could be attributed to ZnGa2O4 spinel structure. This is an indication that the solubility limit of Ga in ZnO ceramics is certainly less than 1 mol at% which was not possible to be detected by means of x ray diffraction (XRD) experiments.
Referência(s)