New Electroluminescence Spectrum from Co-doped ZnS:(Mn, Si) Films Prepared by Chemical Vapor Deposition with Laser Ablation

ABSTRACTCo-doped ZnS:(Mn, Si) films were fabricated. The ZnS was synthesized by a low-pressure thermal chemical vapor deposition. Metal Zn vapor and H2S gas were used as the CVD-precursors. Mn and Si were doped using a laser ablation technique during the ZnS growth. A solid MnSi alloy (Mn:Si = 1:1) was used as the laser ablation target. The films were deposited at the range from 650°C to 750°C. At the deposition temperature of 650°C, only a EL emission peak at 585 nm same as conventional ZnS:Mn films appeared, i.e., the Si co-doping had no effects on the EL spectrum. At the deposition temperature of 700°C, the Si co-doping to ZnS:Mn film caused the shift of the EL emission peak at 585 nm to shorter wavelength by 15 nm and provided new EL emission at 760 nm. The film deposited at 750°C exhibited new UV and blue EL emissions at 390 nm and 450 nm, respectively, although the host material of the film differed from usual ZnS.