Roll-to-roll manufacturing of electronics on flexible substrates using self-aligned imprint lithography (SAIL)

The manufacture of large-area arrays of thin-film transistors on polymer substrates using roll-to-roll (R2R) processes exclusively is being developed. Self-aligned imprint lithography (SAIL) enables the patterning and alignment of submicron-sized features on meter-scaled flexible substrates in the R2R environment. SAIL solves the problem of precision interlayer registry on a moving web by encoding all the geometry information required for the entire patterning steps into a monolithic three-dimensional imprint with discrete thickness modulation. The pre-aligned multiple-step mask structure maintains its alignment regardless of subsequent substrate distortion. Challenges are encountered in relation to the novel nature of using flexible substrates and building toolsets for the R2R processing. In this paper, methods of the SAIL process, the resulting active-matrix backplanes, the trajectory of SAIL process development, and the remaining issues for production are presented.