Design and Growth of Quaternary Mg and Ga Codoped ZnO Thin Films with Transparent Conductive Characteristics

Abstract

This study reports the design growth and characterization of quaternary Mg and Ga codoped ZnO (MGZO) thin films with transparent conductive characteristics deposited on glass substrates by RF magnetron sputtering. The effects of the Ga concentration (from 0 to 2 at %) on the structural, chemical, morphological, optical, and electrical properties of MGZO thin films were investigated. X-ray diffraction study showed that all the MGZO thin films were grown as a polycrystalline hexagonal wurtzite phase with a c-axis preferred orientation and random in-plane orientation. The 2θ value of the (0002) peak of MGZO thin films decreased with increasing Ga concentration. X-ray photoelectron spectroscopy confirmed the Mg and Ga binding energy peaks from the MGZO thin films. The MGZO thin films had a smoother surface morphology. The optical study showed that the band gap energy of MGZO thin films systematically increased from 3.25 to 3.75 eV with increase Ga concentration. The electrical resistivity of the MGZO thin films was improved from 9.5 × 10–2 to 6.89 × 10–4 Ω cm with increasing Ga concentration.

Enhanced Efficiency of Transmit and Receive Module with Ga Doped MgZnO Semiconductor Device by Growth Thickness

“…As an alternative, MgZnO:Ga TCO has been researched for available band-gap engineering through Mg concentration [9,10]. By alloying MgO into the ZnO layer, the optical transmission can increase in the near ultraviolet and visible region.…”

Wide-spectrum Mg and Ga co-doped ZnO TCO thin films for solar cells grown via magnetron sputtering with H2 introduction

“…In order to resolve the dilemma, the incorporation of Mg ang Gropu-III elements into ZnO will be a good selection due to the widened optical band gap and electrical conduction [7][8][9][10][11]. Furthermore, first-principles investigations based on density…”

Comparative study of group-II alloying effects on physical property of ZnGaO transparent conductive films prepared by RF magnetron sputtering

“…Among them, Ga has recognized as the most promising candidate due to its chemical stability and strong resistant to oxidation as well as matched ionic size and covalent radii of 0.62 Å and 1.26 Å with Zn (0.60 Å, 1.25 Å), which ensure the smaller lattice distortion [7][8][9] and it has been demonstrated that a low resistivity of $10 À4 O cm can be realized from the Ga-doped ZnO films, which is comparable with that of ITO [10,11]. While, TCO materials with a wider band-gap for application in optoelectronic devices operating in the ultra violet (UV) regime are strongly required, as an operating regime of optoelectronic device shifts to shorter wavelength recently [12,13] and thus, band-gap widening of the ZnO film is key issue, which should be resolved for employment of ZnO-based TCO in UV range optoelectronic devices.…”