Electroluminescence in oxygen co-doped ZnS:TmF3 and ZnS:Tm, Li thin-film devices

The effects of oxygen co-doping in ZnS:TmF3 and ZnS:Tm, Li thin-film electroluminescent devices are reported. Active layers are deposited in oxygen atmosphere at substrate temperatures of 200 and 300 °C. It is found that by oxygen codoping the luminance of ZnS:TmF3 and ZnS:Tm, Li devices increases, and that this phenomenon becomes marked in the films prepared at a higher substrate temperature.