Vm. Garcia et al., PREPARATION OF HIGHLY PHOTOSENSITIVE CDSE THIN-FILMS BY A CHEMICAL BATH DEPOSITION TECHNIQUE, Semiconductor science and technology, 11(3), 1996, pp. 427-432
Thin films of CdSe were deposited by a chemical bath technique from ci
tratocadmium(II) or tartratocadmium(II) complex ions and N, N-dimethyl
selenourea. The final thicknesses of the films were 0.17 mu m from the
citrate bath and 0.28 mu m from the tartrate bath, when the depositio
ns were made at room temperature. The films are uniform and adherent t
o glass substrates. The as-prepared films are only marginally photosen
sitive with a photocurrent to dark current ratio of < 10 under white l
ight of intensity 2.1 kW m(-2). Annealing the films in air for 30 min-
2 h at 300-450 degrees C results in high photosensitivities, 10(3)-10(
7), depending on the film thickness, bath composition, and the duratio
n and temperature of annealing. The photocurrent rise and decay time a
re short, typically of the order of milliseconds. The combination of f
ilm thickness, annealing temperature and duration of annealing that pr
esents the best photosensitivity for the films is discussed.