PURPOSE: To obtain an electrode structure of a thin zinc oxide film with stable electric characteristics, by interposing a V layer between the thin zinc oxide film and an Al layer and preventing the diffusion of Al into the thin zinc oxide film.

CONSTITUTION: The thin zinc oxide film is used as a piezoelectric body for a surface acoustic wave device, various oscillators, etc. A tuning fork type oscillator which uses the invented electrode structure of the thin zinc oxide film as shown in a figure is constituted by providing the electrode structure of the thin zinc oxide film consisting of the zinc oxide film 12, V layer 13, and Al electrode 14 to a metallic tuning fork 11 made of "Elinvar", etc. This electrode structure is obtained by forming the V layer 13 on the thin zinc oxide film 12 formed by sputtering on the tuning fork 11 by resistance vapor deposition to a 430 thickness and forming the Al electrode 14 thereupon to a 1μm thickness by the electron beam method. This electrode structure is free of the diffusion of Al into the thin zinc oxide film 12, which functions as the piezoelectric body electrically stably.