Physical and Structural Properties of RF Magnetron Sputtered ZnO Films

ABSTRACT

Poly-crystal zinc oxide thin films with c-axis orientation have been successfully grown on the silicon substrate by r.f. magnetron sputtering technique. A systematic study has been made of the influence of substrate temperature on the film structural and optical properties. For SAW device applications, it is necessary for ZnO films to have c-axis oriented crystalline structure. Much lower FWHM values 0.24° is obtained under the substrate temperature at 100°C for gaining effective electromechanical coupling. Crystalline structures, stress, and surface morphology characteristics of the films were investigated by X-ray diffraction, scanning electron microscopy. Reflective Second Harmonic Generation was used to analyze the quality of the ZnO film, and the results from these ZnO films coincide with the X-ray pattern and SEM image. Optical transmittance measurements were carried out by UV-visible spectrophotometer.

Keyword:

• ZnO
• r.f. sputtering
• reflective second harmonic generation