Preparation and Properties of ZnO Thin Film by Thermal Decomposition of Zinc Naphthenate

Abstract

Polycrystalline zinc oxide film was prepared as follows. Zinc naphthenate was coated on a glass or fused silica substrate. The coated zinc naphthenate was decomposed thermally by calcining at 300°C in vacuum or air to form amorphous zinc oxide. On calcining zinc naphthenate at 400°C for 1h, the decomposition was completed and a transparent and uniform film was obtained. However, the amorphous zinc oxide produced by hydrolysis of zinc naphthenate in the presence of small amounts of water (17.5mmHg) crystallized rapidly at 200°C. Consequently, no uniform film was observed, and fine powder of zinc oxide deposited on the substrate. Thus, the uniformity of the film is closely related to the crystallization temperature of amorphous zinc oxide.
The thickness attained to 2μ on repeating the coating and calcining procedures. Preferred orientation with c-axis perpendicular to the film surface developed with an increase in the thickness.
The electrical resistivity of the film having the thickness of 1μ was 10⁹Ω-cm at room temperature. The temperature dependence resistivity had a minimum at 280-290°C and a maximum at 420-430°C.