The ZnO films where crystallites c-axis are unidirectionally aligned in the substrate plane ((112̄0) textured ZnO films) realize shear mode devices. In this study, we have studied the formation mechanism of the (112̄0) textured ZnO film, focusing on the effect of total pressure and partial pressure of oxygen and argon during sputtering deposition. In addition to the X-ray diffraction (XRD) measurement of the films, optical emissions from the RF plasma were analyzed to investigate the effect of ionic species on the growth of the ZnO films. Highly crystallized (112̄0) textured ZnO films were obtained in conditions of low total gas pressure and high oxygen concentration. In these conditions, strong optical emission spectra from oxygen species were strongly observed. The best shear mode electromechanical coupling coefficient k 15 of the film was 0.16, which was 62 % of the value of single crystal.