Keeping up with the trend
With ever evolving technology at our fingertips, it should come as no surprise that we are, in many aspects of ours lives, now becoming dependent on increasingly complex devices. Nowadays, it is crucial to have ultra-portable devices as people instantaneously need to be updated with the latest information available in the vast web. This has strongly contributed to the demand growth for wearable and transparent displays.
Unbeknownst to all, such devices have already been previously developed. The problem with these gadgets is that they usually have low transparency and poor electrical performance. At least until recently. A research team from the Korea Advanced Institute of Science and Technology (KAIST), successfully overcame this obstacle!
Breaking the barrier
Professors Keon Jae Lee and Sang-Hee Ko Park, together with their research team from the Department of Materials Science and Engineering at KAIST, have developed an ultra-thin and transparent oxide thin-film transistors (TFT). This has enabled the team to have an active-matrix back-plane of a flexible display by using the inorganic-based laser lift-off method.
The team fabricated a high-performance oxide TFT array on top of a sacrificial laser-reactive substrate for laser irradiation. Then. the oxide TFT arrays were separated from the sacrificial substrate as a result of reaction between laser and laser-reactive layer, and then transferred onto ultra-thin plastics. Finally, the transferred TFT driving circuit for the flexible display, was attached conformally to the surface of human skin to test the wearability. The attached oxide TFT’s showed high optical transparency of 83% and mobility of even under several cycles of severe bending tests.
With this, the technological barriers for high performance transparent flexible displays have been overcome at a low cost, according to Professor Lee. Furthermore, the device can now be easily transferred onto skin-like substrate for the closest of wearable applications.