Microcup Array Fabricated by Thermal Imprint Lithography for E-Paper Application

Abstract

Thermal imprinting method was developed to provide a microcup array for the application to e-paper, and the imprinted feature was investigated as functions of time and temperature. Even in a short period of time of 2 second, the pattern was imprinted onto a resin to the full depth at a temperature higher than T/Tg = 0.64 (where the Tg is 156°C), however, the hardening process as long as 30 minutes appears to be necessary to achieve the full mechanical strength. We propose a roller imprint process that suffices the two experimental observations and is put to practical use. A large array of microcup having typical dimension in the range of 60–100 µm in width or length, 20–40 µm in height, and 10–20 µm in width of partition walls was able to be fabricated via the roller imprint method.