Review on Gallium Zinc Oxide Films: Material Properties and Preparation Techniques

Abstract

Thin films continue to become more and more integral to numerous applications in today's advancing technologies. In recent years, thin film science has grown world-wide into a major research area. The importance of coatings and the synthesis of new materials for industry have resulted in a tremendous increase of innovative thin film processing technologies. Thin film properties are strongly dependent on the method of deposition, the substrate temperature, the rate of deposition, the background pressure etc. Hardness, adhesion, non porosity, high mobility of charge carriers / insulating properties and chemical inertness, which are possible with a selection of suitable functional materials and deposition techniques. There are number of different techniques that facilitate the deposition of stable thin films of oxide materials on suitable substrates. Material properties of gallium zinc oxide thin films and all the techniques used to deposit thin films are summarized with an elaborative account along with our results.

Efficient dispersants for the dispersion of gallium zinc oxide nanopowder in aqueous suspensions

“…They are about 10 À2 , 6 9 10 À3 , and 5 9 10 À3 mol/L for the adsorptions of PAA-NH 4 , L-PEI, and H-PEI, respectively. Obviously, the data of C t e are very close for the cases of L-PEI and H-PEI, and both are smaller than that of PAA-NH 4 . The easier achieving of L-PEI and H-PEI to the adsorption saturation at lower C t e might be relevant to the less electrostatic repulsion between the adsorbate and adsorptive.…”

“…The traditional transparent conductive oxide (TCO) is indium tin oxide (ITO), which is a very expensive material; thus, numerous doped ZnO compounds, including In 2 O 3doped ZnO, Al 2 O 3 -doped ZnO (AZO), and Ga 2 O 3 -doped ZnO (gallium zinc oxide, GZO), which exhibit competitive advantages of high natural abundance, low cost, nontoxicity, low resistance, high transparency, and good chemical and thermal stabilities, have been proposed as replacements for ITO. [1][2][3][4][5][6][7][8][9][10] Although AZO is the most common among the doped ZnO powders, GZO is the most chemically stable because Ga is less reactive than Al toward environmental oxygen. [11][12][13] To obtain a high quality and homogeneous TCO film for use in optical and electrical devices, 1,14,15 several approaches have been proposed, such as physical vapor deposition, sputtering, chemical vapor deposition, epitaxy, ion plating, spray pyrolysis, and solution growth processes.…”

“…The traditional transparent conductive oxide (TCO) is indium tin oxide (ITO), which is a very expensive material; thus, numerous doped ZnO compounds, including In 2 O 3 ‐doped ZnO, Al 2 O 3 ‐doped ZnO (AZO), and Ga 2 O 3 ‐doped ZnO (gallium zinc oxide, GZO), which exhibit competitive advantages of high natural abundance, low cost, nontoxicity, low resistance, high transparency, and good chemical and thermal stabilities, have been proposed as replacements for ITO . Although AZO is the most common among the doped ZnO powders, GZO is the most chemically stable because Ga is less reactive than Al toward environmental oxygen .…”

(Invited) Ozone Assisted ALD of Doped ZnO as a Transparent Metal

“…AZO has been reported to reach 0.14 m -cm (6), although as with ITO, most reports are about 3x higher. Another donor which has reported, although not extensively, is gallium ( 7 ). Similar to AZO, the minimum resistivity for GZO is reported to be about 0.28 m -cm (8), with most reports closer to 0.5 m -cm.…”

Dispersion of aluminum‐doped zinc oxide nanopowder in non‐aqueous suspensions

“…TCO materials are most frequently cast as thin films, and several approaches are used in film preparation; these include physical vapor deposition, sputtering, chemical vapor deposition, epitaxy, ion plating, spray pyrolysis, and solution growth processes . Of these techniques, the solution growth process of sol‐gel spin coating attracts the highest attention because of its distinct advantages of cost effectiveness, simplicity, and deposition at a high rate; thereby making this method suitable for mass production .…”