CVD diamond: a novel high gamma-coating for plasma display panels?

Minimization of the firing voltage of plasma display panels requires electr ode coatings with high ion-induced secondary electron emission coefficients (gamma -coefficients). This paper discusses the methodology of Paschen-cur ve-based gamma -measurements and compares measured gamma -coefficients of M gO, the standard material for this application, with data measured for CVD diamond of various thicknesses, a-C:H and ta-C films grown on glass. Ne, Ar and Xe discharges are investigated. The negative electron affinity (NEA) o f H-terminated CVD diamond is shown to lead to high gamma -values, stable o peration and low plasma firing voltages that rival or even surpass those of the best quality MgO(111) single crystals with the advantage of diamond be ing less sensitive to panel processing conditions. Replacing the H-terminat ion of diamond by positive electron affinity (PEA) O-termination results in a dramatic increase of the firing voltage, thus demonstrating the importan ce of the electron affinity for ion-induced secondary electron emission. Di amond is found to be particularly interesting for high Xe panel fillings. T he gamma -coefficients of DLC- and ta-C layers are significantly lower and show considerable instability and degradation over time. The advantages and drawbacks of diamond as a PDP cell coating are discussed. (C) 2001 Elsevie r Science B.V. All rights reserved.