Flexible liquid crystal displays (LCDs) have recently attracted great attention since they have potential to open up new application areas of wearable computer, smart cards, and display systems in small packages. However, conventional LC alignment process is not suitable for a plastic substrate because a high temperature process, over 200°C for 1 hour, is required. The plastic substrate will be significantly damaged and deformed during the high temperature process. Therefore, a new technology of processing at a low temperature should be developed. In this paper, we propose a stamping process at room temperature for fabricating a flexible LCD. Figure 1 shows a schematic diagram together with a scanning electron microscopy (SEM) image of our flexible LCD. We first prepared a poly(dimethylsiloxane) (PDMS) master with microgrooves and microstructures. Using the master, the ultraviolet (UV) curable polymer layer, coated on the plastic substrate, was stamped to produce microgrooves. The flexible substrate with microgrooves for both the LC alignment and spacers to maintain the uniform cell gap was shown in Fig. 1. It was found that the azimuthal anchoring energy is about 1.97x10^-5 J/m^2, which is strong enough to align the LC over large area.

This work was supported in part by Korea Research Foundation Grant No. KRF-2004-005-D00165 and the SNU-SDI Display Innovation Program.