ABSTRACT
In general, the base substrate for a flexible OLED display could be a polymer, a metal foil, or “flexible” glass. However, for a foldable display, a polymer would be the best choice. The surface quality of commercial polymer base films can vary significantly, from very good to poor, even for the same film type, and often does not meet the requirements for OLED fabrication. Surface quality is directly related to cleanliness conditions during the film manufacture and postproduction cleaning steps. This chapter presents a summary comparison of the three categories of bare polymer substrate candidates for flexible electronics. The multilayer technology is a promising candidate for OLED encapsulation, although the lengthy time to deposit multiple layers presents a challenge for the cost-effective manufacturing of flexible OLEDs. The chapter describes more details about this multilayer technology, some of it variants, and a relatively new single-layer encapsulation technology based on atomic layer deposition.
