A Solution Metal Oxide-driven 7.5-in. Foldable AMOLED
Instead of conventional silicon-based ones, semiconductors such as metal oxide compounds attract intensive attentions due to their stereostructrally sufficient oxygen vacancies providing defect-less hoping avenues for electronics, yielding a 10x mobility enhancement than amorphous silicon (a-Si). Additionally, the feature of a-Si facility compatibility also leads metal oxide to high processing accessibility and possibility of mass production. To broaden the metal oxide application, a solution phase containing soluble metal oxide (SMO) is conducted to replace the vacuum deposition procedure. Upon slot-die coating procedure, the formation of semiconductor layer is accomplished [1-2]. The SMO is adopted to be the driving thin film transistor (TFT) in our developed 7.5-in. foldable AMOLED display.
The electrical performance of a single unit SMO TFT on polyimide (PI) substrate is shown in Figure 1. A time-dependent thermo-stress measurement reaching to 10K seconds is applied to realize the TFT reliability and its corresponding deviations. It is of worth to note that the TFT unit remains showing extremely less deviations among all curves after 10K seconds driving whether for PBTS (Positive Bias Temperature Stress) or for NBTS (Negative Bias Temperature Stress). In this case, such TFT arrays are designated for controlling the AMOLED.
Sheet-to-sheet procedure is adopted to manufacture the foldable AMOLED display where the PI is laminated on Carrier glass. A 7.5-in. foldable AMOLED display is successfully developed with the appropriate approaches and investigations for stress distribution analysis,thin-film encapsulation and laser liftoff. The prototype is exhibited in Figure 2.
 Y.-H. Chen, S.-C. Chiang, D.-C. Wu, K.-H. Tseng, H.-M. Chang , Y.-Y. Huang, D.-V. Pham, K.-H. Su, M.Marinkovic, A. Merkulov, and R. Anselmann ITC B2-5 (2018).
 Y.-H. Chen, S.-C. Chiang, D.-C. Wu, K.-H. Tseng, Y.-H. Lin, H.-M. Chang, Y.-Y. Huang, D.-V.Pham, K.-H. Su, M. Marinkovic, D. Weber, A. Merkulov and R. Anselmannb, SID 26-2 (2016)
Yen-Yu, Huang was received his doctoral degree of Chemical Engineering of National Tsing-Hua University in 2004 and, subsequently, joined the Chunghwa Picture Tubes (CPT) in 2005. In 2018, he is transferred to CPTTG (Fuzhou, China) to take the responsibility on a G2.5 pilot line and looking/developing the next potential display-related technologies.
Dr. Huang had studied and explored the displayed-related technologies for over 14 years,covering from the conventional STN/TFT-LCD to the recently eye-attracted Flexible Electronics.Dr. Huang had published 100+ patents and put forth 50+ conference papers among these 14 years. Recently, three of his researches were honorably elected as the Distinguished Paper of Display Week in SID (the Society for Information Display) conference in 2017 (1) and 2018 (2), respectively. Additionally, Dr. Huang is the routine invited speaker and frequently giving plenary lectures for planty renown conferences and exhibitions.
He was ever the vice chairman of Technical Committee Group underneath the Taiwan TFT LCD Association (TTLA) since 2014. Now, he is one of the program committee members of WCSM (World Congress of Smart Materials) conference. He is currently leading a nearly 50 people R&D team in CPT China for developing the next 3-5 year potential technologies which include display and its related but not limited.
Chunghwa Picture Tubes Technology Group (CPTTG) is, originally,the world’s important flat panel display parts manufacturer and the leading enterprises among Fujian Electronics industries. At present,CPTTG deeply cultivates into small and medium size panel processing, through the actual control of panel technology research and development, mass production experience and customer resources. Additionally, cover glass manufacturing for touch sensor application and flat panel processing are formed to provide a one- stop solution strategy to the end customers.