In this work, ZnO single layer thin film of 100 nm is deposited on a Si substrate using RF magnetron sputtering. Base pressure of 1.0×10−5 mbar, RF power of 100W at Ar flow 15 sccm and room temperature were process parameters. The average crystallite size of ZnO layer, deposited on Si substrate, using Scherrer's formula was 108.16 nm. XRD verifies the crystalline nature of ZnO with various peaks at (002), (101) and (103) planes. Using AFM technique, ZnO had an Average Surface Roughness (Ra) of 2.75 nm and RMS roughness (Rq) of 3.70 nm. From Hall measurements at room temperature, the authors determined that ZnO is a n-type semiconductor having a resistivity of 1 to 100 Ωcm. The layer's sheet resistance was 7.05×103 Ω/sq, and its resistivity was 7.05×10−2 Ωcm. The Raman spectra analysis confirmed the presence of Raman active modes in the sample, confirming the existence of certain vibrational modes. In PL spectra, an emission peak was observed at 380.30 nm, which closely resembled pure ZnO. These results collectively shows that the ZnO/Si thin films grown on Si demonstrated excellent quality.
Top1. Introduction
In recent years, there has been a notable upsurge in the research and investigations concerning Zinc Oxide (ZnO). This heightened interest can be attributed to this material's unique properties and potential applications. Researchers from diverse fields have been actively exploring the various aspects of ZnO due to its intriguing characteristics and wide range of possible uses. As a result, the scientific community has been increasingly intrigued by the prospects of utilizing ZnO in innovative technologies and applications.
According to research conducted by Jandow et al., 2010, Zinc Oxide (ZnO) exhibits distinctive properties, with its wide band gap of 3.37 eV standing out as a key feature. This unique characteristic makes ZnO a promising material with significant potential for various applications in optoelectronics and piezoelectric devices. As a result of these findings, ZnO has garnered considerable attention as a viable candidate for advancing technologies in these specific fields.
According to research by (Umar et al., 2010), ZnO has a significant exciting binding energy of 60 eV at room temperature, which is helpful for a variety of applications. Additionally guarantees its suitability for UV photodetectors, room-temperature LEDs, solar cells, and gas monitors (R. Romero et al., 2004, R. Ghosh, D. & Basak, 2007, S. Sharma & C. Periasamy, 2014, S. Sharma et al., 2014). In several transparent conducting films (TCFs), ZnO is a commonly used transparent conducting substance. ZnO thin films have been documented to be produced using a variety of techniques, which includes sol-gel, thermal vapour deposition, pulsed laser deposition, e-beam deposition, and RF sputtering (L. Znaidi, 2010, pp.18-30, B.D. Yao et al., 2002, S.H. Bae et al., 2001, R. Al Asmar et al., 2006). Among these methods, RF sputtering is a very useful technique for the deposition of ZnO. Because in the RF sputtering process, various parameters like pressure, temperature, deposition time, gas flow rate, and RF power can regulate the characteristics of thin films that are being grown. The selection of the substrate material is a crucial factor in the deposition process of ZnO thin films. The various substrates used to deposit ZnO thin films include PPC plastic (Jandow et al., 2010), sapphire (Al2O3) (Pant P et al., 2009), soda lime glass (Jia G et al., 2012), Si (Rouhi J et al., 2014), GaAs (Mauricio MR et al., 2009), and polyimide (Li TC et al., 2012). Here, we have deposited ZnO on Si (silicon) substrate and further we are going to fabricate metal-dielectric multilayers for various optoelectronic applications (Vikas Sharma et al., 2017, Satyavir Singh et al., 2018, V. Sharma et al., 2016, Vikas Sharma et al., 2015, D. L. Raimondi & E. Kay, 1970, SH Ribut et al., 2019). This study aims to investigate the impact of ZnO thin film growth on a silicon substrate, focusing on its structural, electrical, and optical properties. X-ray diffraction (XRD) was employed to analyze the structural characteristics, while atomic force microscopy (AFM) was utilized to study the surface properties. Hall measurements were conducted to assess the electrical properties, and Raman spectroscopy was employed to analyze the optical properties of the ZnO thin films. The objective of this work is to study the effect of structural, electrical, and optical properties of ZnO thin films grown on the silicon substrate. The structural properties were characterized by X-ray diffraction (XRD), surface analysis was done by using atomic force microscopy (AFM), electrical properties were by Hall measurements, and optical properties were analysed by using Raman spectroscopy.