AUTHOR=Priya Bhanu , Jasrotia Priya , Kumar Arun , Singh Vinamrita , Jire L. Hmar Jehova , Kumar Raj , Kulriya Pawan Kumar , Kumar Tanuj 

TITLE=Structural, optical, and electrical properties of V2O5 thin films: Nitrogen implantation and the role of different substrates

JOURNAL=Frontiers in Materials

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2022.1049189

DOI=10.3389/fmats.2022.1049189

ISSN=2296-8016

ABSTRACT=<p>This report investigates the effect of substrate and nitrogen (16 keV N<sup>+</sup>) ion implantation on the structural, morphological, compositional, and electrical properties of V<sub>2</sub>O<sub>5</sub> thin films which are grown by thermal evaporation on various substrates, including glass, Si, and sapphire (termed V<sub>2</sub>O<sub>5</sub>:Gl, V<sub>2</sub>O<sub>5</sub>:Si, and V<sub>2</sub>O<sub>5</sub>:Sp, respectively). Structural analysis showed the formation of the mixed (<italic>α</italic>, and β-V<sub>2</sub>O<sub>5</sub>) phases on all substrates; however, the β-V<sub>2</sub>O<sub>5</sub> phase is highly dominant in the V<sub>2</sub>O<sub>5</sub>:G and V<sub>2</sub>O<sub>5</sub>:Si samples. A deformation in the β-phase of V<sub>2</sub>O<sub>5</sub> thin film under ion implantation-induced strain results in a change of crystallite size. Irradiation suppresses XRD peaks in relative intensities, indicating partial amorphization of the film with defect formation. Microstructural analysis confirmed the formation of uniform-sized nanorods for V<sub>2</sub>O<sub>5</sub>:Si, whereas isolated crystallites were formed for other types of substrates. Thermal conductivity may influence the size and shapes of V<sub>2</sub>O<sub>5</sub> crystallite forms on different surfaces. Silicon absorbs heat more effectively than sapphire or glass, resulting in nanorod formation. A decrease in optical bandgap and electrical conduction has been observed due to increased oxygen vacancies, induced electron scattering, and trapping centres on N<sup>+</sup> implantation. The present study thus offers the unique advantage of simultaneous reduction in optical band-gap and conductance of V<sub>2</sub>O<sub>5</sub> thin films, which is important for optoelectronic applications.</p>