Speaker: Assistant Professor, Saeroonter Oh (Division of Electrical Engineering, Hanyang University)
Date & Time: 2017. 11. 1. 수요일 17:00
Where: 융대원 D-122호
Metal-oxide thin film transistors (TFTs) are becoming the mainstream backplane technology for high-resolution large screen displays. Recent developments in oxide TFTs show high mobility exceeding 50 cm2/Vs, good stability characteristics comparable to LTPS (low-temperature poly-silicon), and integration on plastic substrates for a large range of flexible applications including consumer electronics, smart cars, and wearable computers. Particularly, self-aligned coplanar structure amorphous InGaZnO (a-IGZO) TFTs are implemented in mass produced ultra-high-definition OLED displays.
In this talk, research development efforts to improve the device performance and stability of self-aligned a-IGZO TFTs will be shown. First, the device characteristics of top-gate self-aligned structure and bottom-gate structure will be compared in terms of interfacial characterization, DOS extraction and DOS-based device simulation. Next, we characterize the interface of self-aligned a-IGZO TFTs to understand the positive bias temperature stress (PBTS) instability mechanism. Minimization of the interfacial trap density caused by excess oxygen improves the PBTS significantly. Lastly, even with good PBTS stability, oxide TFTs suffer from photo-degradation effects under illumination. A novel approach to quantitatively assess the light influx will be shown. Suppression of light influx can be achieved through optimization of the device structure and layout.
Ph.D Electrical Engineering, Stanford University, Stanford, CA, USA 
M.S. Electrical Engineering, Stanford University, Stanford, CA, USA 
B.S. Electrical Engineering, KAIST, Daejeon, Korea 
Assistant Professor, Division of Electrical Engineering, Hanyang University ERICA Campus [2016. 3 – present]
Chief Research Engineer, R&D Center, LG Display [2010. 9 – 2016. 2]
초청자 : 융합과학부 나노융합전공 김연상 교수 (연락처 : 031-888-9131, firstname.lastname@example.org)