ZnO:Zn phosphor thin films prepared by filtered arc deposition

ZnO:Zn phosphor thin films, which can be used in field emission displays, were prepared by filtered are deposition. Depositing parameters, including bias and temperature of the substrates, duct current and partial pressure of O-2 in the depositing chamber; were varied to synthesize the films. Both dc and rf bias were utilized in the process. The structure, thickness, luminescent intensity, and morphology of the films were investigated. Most of the as-deposited films contained both crystalline and amorphous phases. It was found that lower bias, lower substrate temperature rf bias, and lower duct current tended to obtain thicker films. Neither lower: nor higher O-2 concentration in the chamber obtained thicker films. There are two categories of luminescent peaks, the UV/violet emission (370-420 nm) and the blue/green light (470-530 nm), in the deposited ZnO:Zn films. An interesting relation between PL intensity and morphology was found. Some samples with a special type of individual tip-like structures showed stronger luminescence in a magnitude than others. The forming of the tip structures may be due to the bombarding effect of the plasma with high energy during the deposition and that there were less boundaries or defects between the individual tips may account for the stronger luminescence. (C) 2001 American Vacuum Society.