Preparation and Physical Properties of CdSe Semiconductor Films by Ultrasonic Chemistry Method

摘要

CdSe films have been prepared successfully by an ultrasonic chemical bath method, with CdCl_2?2.5H_2O and Na_2SeSO_3 as precursors, and trisodium citrate as complexing agent. The films were characterized by XRD, AFM, and UV-Vis. The results showed that the CdSe films were n-type semiconductor and had absorption in the visible region. The CdSe film electrode had higher electron transfer rate, which leads to a substantial improvement on the photocurrent. Optimal condition for preparing the CdSe thin films were as following: the ratio of Cd~(2+) to trisodium citrate was 1:1.5, the ratio of Cd~(2+) to Se~(2+) was 2.5:1, the pH value was 10, the deposition time was 2.5h, and the annealing temperature was 350°C.