Roll-to-roll sputter deposition on flexible glass substrates

Flexible glass is very thin glass below 100 μm, and flexible enough to be wound in a roll. Flexible glass is a very attractive substrate when we consider the roll-to-roll production of flexible displays, because it has thermal stability up to the temperature range for the display fabrication, excellent barrier properties, a very smooth surface and high transparency. However, the roll-to-roll deposition on the flexible glass is still not easy because of the fragility of the glass and the number of the reports is limited. s paper, we demonstrated successful roll-to-roll depositions of ITO on flexible glass 50 μm and 100 μm thick, 300 mm wide and up to 50 m long, using a compact sputter roll-coater with some modifications for the flexible glass handling. A 190 nm ITO coating deposited on the 50 μm thick flexible glass showed the sheet resistance to be as low as 7.5 Ω/sq when heating the substrate to about 250 °C. We also demonstrated continuous roll-to-roll deposition of 24 nm ITO on 100 μm thick and 50 m long flexible glass substrate. The properties of this coating were revealed to have 102 Ω/sq sheet resistance and 90% light transmission. Through these experiments, we demonstrated the feasibility to use flexible glass as the substrate for the roll-to-roll vacuum deposition process.