Conversion from p- to n-Type Conductivity in CuO Thin Films Through Zr Doping

• Published in: Journal of electronic materials 2022-10, Vol.51 (10), p.5644-5654
• Main Author: Baturay, Şilan
• Format: Article
• Language: English
• Subjects: Carrier density; Carrier mobility; Characterization and Evaluation of Materials; Chemistry and Materials Science; Conversion; Copper oxides; Current carriers; Diffraction patterns; Dislocation density; Doping; Electrical properties; Electrical resistivity; Electronics and Microelectronics; Energy bands; Energy gap; Hall effect; Hole mobility; Instrumentation; Materials Science; Microscopy; Nanostructure; Optical and Electronic Materials; Optical properties; Original Research Article; Parameters; Room temperature; Soda-lime glass; Solid State Physics; Spin coating; Thickness; Thin films; Topology; Transmittance
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-022-09836-9

CuO films with Zr doping were successfully fabricated on substrates of soda-lime glass (SLG) using a spin-coating method at various doping concentrations. X-ray diffraction (XRD) patterns for pure and Zr-doped CuO thin films indicated that all thin CuO films have a monoclinic polycrystalline nature, with two maximum peaks (−111) and (111). The dislocation density values of the (−111) and (111) planes are increased from 13.4 × 10 14 to 34.9 × 10 14  m −2 and from 26 × 10 14 to 42.7 × 10 14  m −2 , respectively, owing to the expansion of structural parameters with Zr dopant content. Scanning electron microscopy (SEM) indicated nanostructure particles uniformly distributed on all thin-film surfaces without any agglomerated nanostructure particles. The thickness of CuO films in conjunction with Zr doping is approximately 460 nm. The EDX spectrum of pure CuO in thin film contains Cu and O elements; 1%, 2%, and 3% Zr-doped CuO thin films contain Zr, Cu, and O elements, as expected. Atomic force microscopy (AFM) figures indicate that the surface topologies of thin films are uniformly distributed. Ultraviolet–visible spectroscopy (UV–Vis) measurements of the thin films revealed that the transmittance increased from 25% to 45% in the visible range with increasing Zr concentration at room temperature. The energy band gap increased from 1.67 to 2.03 eV with increasing Zr concentration. At room temperature, a Hall effect system was used to investigate the electrical parameters, including carrier concentration, resistivity, conductivity type, and hole mobility of the CuO films with Zr doping. Conductivity type conversion was observed with 2% and 3% Zr-doped CuO, and confirmed by capacity–voltage ( C - V ) measurements. The charge-carrier concentration of the samples ranged from 1.08 × 10 16 to 5.06 × 10 18  cm −3 with Zr doping. Thus, the optical and electrical properties of CuO thin film such as the band gap energy, transmittance, and carrier mobility can be modified. Graphical Abstract