Surface aging mechanisms of AC plasma display panels

Excellent life performance is being achieved for ac plasma display panels through understanding of the causes of voltage changes, surface overcoat material research, and adjustment of the manufacturing process to eliminate contaminants. It has been found that surface aging phenomena are dominant in many practical cases. Because of prefereutial operation patterns (i.e., alpha numerics), a differential aging pattern may evolve. The differential pattern is the result of voltage changes which are different for heavily operated and lightly or nonoperated cells. It is shown that the nature and extent of surface changes are dependent on overcoat material selection and the presence (or absence) of contaminants introduced during manufacture. With the use of thin overcoat layers in contact with the gas, it is necessary to be aware of the possibility of surface film removal by sputtering. The effects of significant variables: gas pressure and composition surface material, and operating voltage are discussed.