Blue SrS: Cu thin-film electroluminescent devices grown by hot-wall deposition using successive source supply

SrS:Cu, Cl thin- film electroluminescent (TFEL) devices have been prepared by hot- wall deposition using a successive supply of source materials. The TFEL devices show blue EL emission with the chromaticity coordinate of (0.19, 0.28). The luminance and the efficiency at 1 kHz drive are 100 cd/m(2) and 0.1 lm/W, respectively. EL emission is observed at both the leading and the trailing edge of the applied pulse voltage. The presence of trailing edge emission implies that Cu+ centers are ionized during EL excitation, and then electrons are subsequently captured by ionized Cu2+ centers giving rise to the EL emission. (C) 1998 American Institute of Physics. [S0003-6951(98)04939-0].