Abstract

Zinc oxide is a most promising thin film material for use in integrated optical devices because of its high index of refraction, low optical loss, strong acousto-optical, electro-optical and nonlinear optical coefficients and its large piezoelectric constants. Optical losses less than 1 dB/cm have been reported for films grown by CVD on sapphire (1). Strong acousto-optic interactions have been observed (2) and electro-optic modulator and switching action demonstrated (3). To obtain a high optical quality zinc oxide it has been necessary to deposit the films on crystalline substrates such as sapphire. The low optical losses measured on crystalline substrates have now been achieved on amorphous substrates with ZnO films sputter deposited on oxidized silicon substrates. The optical waveguide propagation properties of these films are the subject of this paper. Films of this type have been used for SAW device development and possess piezoelectric and acoustic properties approaching single crystal zinc oxide (4).

© 1980 Optical Society of America