Structural, photoconductive, thermoelectric and activation energy measurements of $V$-doped transparent conductive $SnO_{2}$ films fabricated by spray pyrolysis technique

Pramana

H AZIMI-JUYBARI¹  R NASIRAEI¹  M R FADAVIESLAM1¹ 

[1] School of Physics, Damghan University, Damghan, Iran$$

关键词: Thin film;    spray pyrolysis;    $SnO_2$:$V$;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

This report investigated the structural, optical and electrical properties of V-doped $SnO_{2}$ thin films deposited using spray pyrolysis technique. The $SnO_{2}$:$V$ films, with different $V$-content, were deposited on glasssubstrates at a substrate temperature of $550deg C$ using an aqueous ethanol solution consisting of tin and vanadium chloride. X-ray diffraction studies showed that the $SnO_{2}$:$V$ films were polycrystalline only with tin oxide phasesand the preferred orientations are along (1 1 0), (1 0 1), (2 1 1) and (3 0 1) planes. Using Scherrer formula, the grain sizes were estimated to be within the range of 25--36 nm. The variation in sheet resistance and optical direct band gap are functions of vanadium doping concentration. Field emission scanning electron microscopy (FESEM) revealed the surface morphology to be very smooth, yet grainy in nature. Optical transmittance spectra of the films showed high transparency of about $approx 69--90%$ in the visible region, decreasing with increase in $V$-doping. The direct band gap for undoped $SnO_{2}$ films was found to be 3.53 eV, while for higher V-doped films it shifted toward lower energies in the range of 3.27--3.53 eV and then increased again to 3.5 eV. The Hall effect and Seebeck studies revealed that the films exhibit n-type conductivity. The thermal activation energy, Seebeck coefficient and maximum of photosensitivity in the films were found to be in the range of 0.02--0.82 eV (in thelow-temperature range), $0.15--0.18 {m mV K^{−1}}$ (at $T = 350 K$) and 0.96--2.84, respectively.

【 授权许可】

Unknown