Internal Stress of ITO, IZO and GZO Films Deposited by RF and DC Magnetron Sputtering

Abstract

Mechanical properties such as internal stress or adhesion of transparent conductive oxide (TCO) films are quite important to guarantee the patterning accuracy and the durability for various kinds of commercial applications. In this study, representative TCO films with the thickness of about 200 nm, such as tin-doped indium oxide (ITO), indium-zinc oxide (IZO), and gallium-doped zinc oxide (GZO) films were deposited on unheated glass substrate by rf and dc magnetron sputtering using corresponding oxide targets under various total gas pressure (Ptot) from 0.3 to 3.0 Pa. The internal stress of these TCO films was measured by cantilever method using 50 µ m thick 50mmx5mm micro-sheet glass substrates in relation to the Ptot during the deposition. The ITO films deposited at Ptot lower than 0.7 Pa were polycrystalline and showed large compressive stress, while the amorphous ITO films deposited at 1.5-3.0 Pa showed a very slight tensile stress. On the contrary, the all the IZO films with various thicknesses (50-750 nm) deposited at Ptot of 0.3-3.0 Pa showed entirely amorphous structure, where the compressive stress of IZO films was lower than that of ITO films. Whereas, all the GZO films deposited under Ptot from 0.3 to 5.0 Pa showed polycrystalline structure with <001> preferred orientation, where the compressive stress showed almost constant for all the films.

Characterization of the density of states of polymorphous silicon films produced at 13.56 and 27.12 MHz using CPM and SCLC techniques

“…For the r s measurements a cantilever method was used, employing 50 lm thick 50 · 50 mm micro-sheet glass subtracts, being r s determined by [11] …”

Antifogging effects of a socket-type device with the superhydrophilic, titanium dioxide–coated glass for the laparoscope

“…The findings showed that this phenomenon was attributable to the repeated reflections and inflections of the ultraviolet ray from the light source of the endoscope on the TiO 2 coating and in the glass. The sputtering method allowing uniform thin coating [6] and the use of the quartz (Pyrex) glass allowing the achievement of both lamellation and strength were ascertained to potentially reduce scattered light.…”

Ga-Doped ZnO Coating—A Suitable Tool for Tuning the Electrode Properties in the Solar Cells with CdS/ZnS Core-Shell Quantum Dots

“…After optimization of both parameters, 85% transmittance in the visible range has been reported. Further, the internal stress of the GZO and ITO films and its effect on the visible transmission has been investigated as a function of the total sputtering pressure [17]. Recently, ZnO:Ga-graded ITO electrodes in perovskites solar cells have been reported [18].…”