Highly transparent and conductive double-layer oxide thin films as anodes for organic light-emitting diodes

摘要

Double-layer transparent conducting oxide thin film structures containing In-doped CdO (CIO) and Sn-doped In_2O_3 (ITO) layers were grown on glass by metal-organic chemical vapor deposition and ion-assisted deposition (IAD), respectively, and used as anodes for polymer light-emitting diodes (PLEDs). These films have a very low overall In content of 16 at. %. For 180-nm-thick CIO/ITO films, the sheet resistance is 5.6 Ω/□, and the average optical transmittance is 87.1% in the 400-700 nm region. The overall figure of merit (Φ = T~(10)/R_(sheet)) of the double-layer CIO/ITO films is significantly greater than that of single-layer CIO, IAD-ITO, and commercial ITO films. CIO/ ITO-based PLEDs exhibit comparable or superior device performance versus ITO-based control devices. CIO/ITO materials have a much lower sheet resistance than ITO, rendering them promising low In content electrode materials for large-area optoelectronic devices.