Study of low power deposition of ITO for top emission oled with facing target and RF sputtering systems

Abstract

Deposition of ITO as top transparent electrode was studied using two deposition systems with and without direct contact to working plasma; namely with conventional RF-magnetron planar (RSS) and pulsed-DC facing target sputtering systems (FTS). Test devices were made on glass substrates and consisted of (from bottom up) ITO/4 Organic Layers/ITO. Depositions were performed at low deposition powers; 30 and 60 watts, to reduce damages by energetic sputtered particles to underlying organic layers. Test devices from both sputtering systems were found to function well. Leakage current density at -5 V reverse bias were relatively constant from 0.3 and 0.4 mA/cm2 at 30 W and 60 W in FTS, while the values were found to increase from 0.001 to 0.2 mA/cm2 at 30 W and 60 W in RSS. © 2008 IOP Publishing Ltd.