Photolithography versus lift off process for patterning of sputtered indium tin oxide for flexible displays

Authors

Mariya Aleksandrova, Technical University of Sofia, Bulgaria, Department of Microelectronics, 8, Kliment Ohridski blvd, bl. 1,Follow
Georgy Kolev, Technical University of Sofia, Bulgaria, Department of Microelectronics, 8, Kliment Ohridski blvd, bl. 1Follow
Ivelina Cholakova, Technical University of Sofia, Bulgaria, Department of Microelectronics, 8, Kliment Ohridski blvd, bl. 1,Follow
Georgy Dobrikov, Technical University of Sofia, Bulgaria, Department of Microelectronics, 8, Kliment Ohridski blvd, bl. 1Follow
Georgy Bodurov, Central Laboratory of Solar Energy and New Energy Sources, Bulgarian Academy of Science, Sofia, Bulgaria, bul. “Tsarigradsko Chaussee”, 72.Follow

Abstract

Indium tin oxide (ITO) is deposited by RF sputtering on polyethylene terephthalate substrate as transparent electrode for flexible display applications. The produced coatings are patterned in form of digits for seven-segmented indication via conventional photolithography and lift off process. The influence of the exposure dose, etching and stripping solution on the electrophysical properties of ITO films and achieved image resolution were investigated. The sheet resistance increases from 66.5 Ω/square to 101.9 Ω/square after wet etching. The undercut is 6μm for 2 mm wide segment, which is satisfactory for digital indication. After lift off, no undercut is observed, but ITO sheet resistance increases to 197 Ω/square. In both cases ITO film’s transmittance for the visible light remains higher than 89 %.

Recommended Citation

Aleksandrova, Mariya; Kolev, Georgy; Cholakova, Ivelina; Dobrikov, Georgy; and Bodurov, Georgy (2013) "Photolithography versus lift off process for patterning of sputtered indium tin oxide for flexible displays," International Journal of Thin Film Science and Technology: Vol. 2 : Iss. 2 , PP -.
Available at: https://digitalcommons.aaru.edu.jo/ijtfst/vol2/iss2/2