Early phase discharge voltage characteristics of La0.5Sr0.5CoO3 used as a cathode material

Abstract

AbstractLa0.5Sr0.5CoO3 was used as a cathode material for the first time in plasma display panels installed in handheld personal computers. It has favorable antisputtering characteristics and stable discharge characteristics in gases. Cathodes made of La0.5Sr0.5CoO3 have a unique early‐phase discharge voltage characteristic, in which the discharge voltage continues to decrease from the starting value. In this report, the discharge voltage shift of La0.5Sr0.5CoO3 was investigated by analysis of a DC plasma panel that was fabricated as a prototype. It is assumed that the discharge voltage shift is caused by a current density shift in the cathode surface, and that the current density shift is caused by the surface profile of the cathode particles. In order to elucidate the mechanism involved, a spherical model was applied to the variation of the discharge voltage, and the calculated and measured values were compared. The calculated values correspond approximately to the measured values. This spherical model is useful for predicting the change in the discharge voltage up to the attainment of its minimum value. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(6): 41–47, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10201