Popis: |
Thin films of zinc sulfide (ZnS) doped with donors and acceptors are prepared by metalorganic chemical vapor deposition (MOCVD) under reduced pressure. The photoluminescence spectrum of a ZnS: Ag, Cl film shows a peak at 460 nm. This emission is attributed to the donor-acceptor (D-A) pair emission from the time-resolved spectra. A ZnS: Ag, Cl thin film is used in an AC-coupled EL device having a MIS structure, ITO-ZnS: Ag,Cl(600 nm thick)-Ta 2 O 5 -Al. This device has a blue broad band emission with a peak at 467 nm. Luminance of 30 cd/m 2 is obtained under 5 KHz sinusoidal voltage excitation. |