Effect of Oxygen and Aluminum Incorporation on the Local Structure of GaN Nanowires: Insight from Extended X-ray Absorption Fine Structure Analysis

Autor(es)

Parida, Santanu ^[1] ; Sahoo, Madhusmita ^[1] ; Abharana, N. ^[2] ; Tromer, Raphael M. ^[3] ; Galvao, Douglas S. ^{[3, 4]} ; Dhara, Sandip ^[1]

Afiliação do(s) autor(es)

^[1] Homi Bhabha Natl Inst, Indira Gandhi Ctr Atom Res, Surface & Nanosci Div, Kalpakkam 603102, Tamil Nadu - India

^[2] Bhabha Atom Res Ctr, Atom & Mol Phys Div, Mumbai 400085, Maharashtra - India

^[3] Univ Estadual Campinas, Appl Phys Dept, BR-13083970 Campinas, SP - Brazil

^[4] Univ Estadual Campinas, Ctr Computat Engn & Sci, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Physical Chemistry C; v. 125, n. 5, p. 3225-3234, FEB 11 2021.
• Citações Web of Science: 0

Resumo

A thorough investigation of local structure, influencing the macroscopic properties of the solid, is of potential interest. We investigated the local structure of GaN nanowires (NWs) with different native defect concentrations synthesized by the chemical vapor deposition technique. Extended X-ray absorption fine structure (EXAFS) analysis and semiempirical and density functional theory (DFT) calculations were used to address the effect of dopant incorporation along with other defects on the coordination number and bond length values. The decrease of the bond length values along preferential crystal axes in the local tetrahedral structure of GaN emphasizes the preferred lattice site for oxygen doping. The preferential bond length contraction is corroborated by the simulations. We have also studied the impact on the local atomic configuration of GaN NWs with Al incorporation. AlxGa1-xN NWs are synthesized via novel ion beam techniques of ion beam mixing and post-irradiation diffusion process. The change in the local tetrahedral structure of GaN with Al incorporation is investigated by EXAFS analysis. The analysis provides a clear understanding of choosing a suitable process for ternary III-nitride random alloy formation. The study of the local structure with the EXAFS analysis is corroborated with the observed macroscopic properties studied using Raman spectroscopy. (AU)

• Processo FAPESP: 13/08293-7 - CECC - Centro de Engenharia e Ciências Computacionais
• Beneficiário: Munir Salomao Skaf
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs