AVS 47th International Symposium
    Flat Panel Displays Monday Sessions
       Session FP-MoA

Paper FP-MoA10
Mechanical Properties and Thin Film Transistor Performance for Flexible Displays

Monday, October 2, 2000, 5:00 pm, Room 313

Session: Flexible Displays
Presenter: S. Wagner, Princeton University
Authors: S. Wagner, Princeton University
H. Gleskova, Princeton University
Z. Suo, Princeton University
Correspondent: Click to Email
Flexible displays have become of considerable near-term interest for portable computing and communication devices, because flexibility is equated with ruggedness and light weight. In these applications the displays may be flexed only a few times before they become permanently embedded, often in nonplanar configurations. Longer-term applications include products that will be flexed throughout their entire lives, for example, rollable displays and electronic books. While in some instances display components may be deformed plastically during fabrication, one may seek to exclude plastic deformation during use. Elastic deformation may be induced by bending, coiling, twisting, or stretching. We will focus on the best-understood case of elastic deformation by bending. Three question arise when a thin film transistor (TFT) is subjected to bending: (i) How much bending can a TFT tolerate? (ii) What happens in the TFT during bending? (iii) How does fatigue from repeated bending manifest itself? We have found that: (a) We are beginning to understand elastic deformation of TFT/substrate structures, but still need to understand plastic deformation; (b) Amorphous silicon TFTs are more sensitive to tensile than to compressive strain, and surface passivation may make them more resistant against tensile failure; (c) The mechanical properties of substrate and encapsulation should be tuned such that the circuit comes to lie in the neutral plane.