Optimized Activation of Solution-Processed Amorphous Oxide Semiconductors for Flexible Transparent Conductive Electrodes

Choi B. D. , Park J., Baeg K., Kang M., Heo J. S. , Kim S., ...More

ADVANCED ELECTRONIC MATERIALS, vol.4, no.1, 2018 (Journal Indexed in SCI) identifier

  • Publication Type: Article / Article
  • Volume: 4 Issue: 1
  • Publication Date: 2018
  • Doi Number: 10.1002/aelm.201700386


Here, the preparation of transparent amorphous oxide semiconductor (AOS) films with unprecedented conductivity via an optimized activation process under hydrogen atmosphere for applications in solution-processed large-area optoelectronics is reported. Owing to their high cost and mechanical vulnerability, conventional vacuum-processed indium-tin oxide (ITO) electrodes are inappropriate for use in next-generation flexible and wearable electronic devices and systems. As an alternative to the ITO electrodes, solution-processed AOS films, such as alpha-IZO and alpha-ZITO, with an optimized composition and postreduction treatment under hydrogen show the highest electrical conductivity of approximate to 300 S cm(-1) and a high optical transmittance of over 90% at 550 nm. The microstructures and electrical properties of these AOS films are also studied in order to determine the optimized chemical composition and postreduction conditions. It is found that a controlled hydrogen reduction treatment of AOS films is critical for achieving high electrical conductivity by suppressing the surface morphology degradation and grain boundary disconnection. Furthermore, the alpha-IZO transparent conductive electrodes are successfully implemented for high efficiency organic photovoltaic cells based on the PTB7/PC71BM active layers. This technique promises the low-cost fabrication of high mobility and/or conductive AOSs for their applications in large-area transparent and flexible optoelectronics.