Photoconductivity study of amorphous carbon nitride films for opto-electronics devices

摘要

Single layered amorphous carbon nitride (a-CN_x) films and a multilayered a-CN_x film were prepared by reactive radio frequency magnetron sputtering of a graphite target and nitrogen gas. This paper describes the optical, electrical and opto-electrical properties of the a-CN_x films. The optical band-gap of the single layered films increased with increasing nitrogen concentration, which was controlled through the deposition temperature. The photo-sensitivity values, a ratio of photo- and dark-conductivities, ranged from 2.2 to 6.0. In the multilayered film consisting of four a-CN_x layers deposited at different temperatures, the photosensitivity of the multilayered film was over 1.2 times as compared with that of the single layered films.