Development of a highly sensitive UV sensor using Al, Ga, and In-doped NiO thin films via nebulizer spray pyrolysis method for photodetector applications

• Published in: Journal of materials science. Materials in electronics Vol. 33; no. 15; pp. 11753 - 11767
• Main Authors: Raj, I. Loyola Poul, Valanarasu, S., Asuntha, A., Rimal Isaac, R. S., Shkir, Mohd, Algarni, H., AlFaify, S.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-05-2022; Springer Nature B.V
• Subjects: Aluminum; Characterization and Evaluation of Materials; Chemistry and Materials Science; Dopants; Gallium; Glass substrates; Impurities; Materials Science; Nickel oxides; Optical and Electronic Materials; Optoelectronics; Quantum efficiency; Spray pyrolysis; Thin films
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-022-08140-w

Fabrication of highly sensitive p-type-based UV photoconductor with less expense is of utmost importance for next-generation optoelectronic applications. In the current study, high-purity pristine and metallic elements of Aluminum (Al), Gallium (Ga), and Indium (In)-doped NiO thin films were successfully grown on glass substrate at 475 ºC via a cost-effective nebulizer spray pyrolysis route. The effect of trivalent metallic elements on physicochemical characteristics was studied elaborately. XRD examination shows that the doped metal impurity element improved the NiO thin film’s crystallinity and was found to be high for Al impurity. The captured FE-SEM images declared the formation of nanograins and the dopant introduction has altered the size of the grain. Optical data prove the enhanced absorption in the UV region and narrowing bandgap energy. The PL spectrum (λ
exc
 = 325 nm) exhibits a stout luminescent center at 478 nm and five weak luminescent centers at 387, 415, 437, 450, and 521 nm, respectively. All the doped NiO thin films show exceptional UV photodetection ability. However, compared with the other two dopants of Ga and In, the NiO thin film doped with Al shows outstanding responsivity (40 × 10
− 2
 A/W), detectivity (14 × 10
9
Jones), and external quantum efficiency (94%).