Hoon-Kee Min

47.2: 2.8‐inch WQVGA Flexible AMOLED Using High Performance Low Temperature Polysilicon TFT on Plastic Substrates

This paper reports a low-temperature polycrystalline silicon (LTPS) fabrication process on plastic substrate for a flexible AMOLED display. Characteristics of fabricated TFTs showed excellent performance with field effect mobility of 124.1 cm2/V-s, on/off ratio of >108, subthreshold slope of 0.30V/dec, and threshold voltage of −2.03V. Internal scan drive circuits, 1:3 demux, and compensation circuits were successfully integrated on the backplane of a 166ppi 2.8″ WQVGA flexible AMOLED panel.

47.1: Invited Paper: Highly Robust Flexible AMOLED Display on Plastic Substrate with New Structure

A new flexible TFT backplane structure with improved mechanical reliability has been fabricated on a plastic substrate using amorphous indium-gallium-zinc-oxide (a-IGZO) thin film transistors. The panel withstood 10,000 bending cycles at a bending radius of 5 mm without any noticeable TFT degradation. After the bending test, change of Vth, mobility, sub-threshold slope, and gate leakage current were only −0.10V, −0.11cm2/V-s, 0.01V/decade, and −1.03×10-−12A, respectively. No line defects, dark spots, or bright spots appeared after 10K bending cycles at a bend radius of 10 mm.

16.2: World-Best Performance LTPS TFTs with Robust Bending Properties on AMOLED Displays

This study reported a low temperature polycrystalline silicon LTPS thin film transistor TFT fabrication process on plastic substrates for flexible display applications. Polycrystalline silicon poly-Si films were formed by excimer laser annealing ELA method. It was found by ELA thermal simulation that there was around 70 □ on plastic surface during ELA crystallization process. The excimer laser irradiated film was analyzed by using various spectroscopic methods such as X-ray diffraction, scanning electron microscopy, and atomic force microscopy. Dehydrogenation and activation processes were performed by a conventional LTPS method without causing any plastic substrate distortion. The fabricated poly-Si TFT on a flexible backplane shows a very good performance with field effect mobility of 95.3 cm2/Vs, on/off ratio current ratio > 108, and threshold voltage of −1.6 V. Bending tests after a delamination process were also performed with TFT backplane samples.

41.4: AMOLED based on Silicon-On-Glass (SiOG) Technology

We have demonstrated that the single crystalline silicon films on the glass substrates can be utilized in the conventional mass production lines. The single crystalline Si layers were transferred to the 370 mm × 470 mm glass substrates using Silicon-On-Glass (SiOG) technology. Using the thin film transistor backplanes made by conventional CMOS technology, 2.4″ qVGA AMOLED with integrated circuits were successfully fabricated. A completed 2.4″ qVGA AMOLED module shows wide viewing angle (> 170°) and 73% color gamut. The advantages of SiOG technology and its significances will be presented.

Characterization of laser annealed polycrystalline silicon films on various substrates

AbstractThe structure and property of eximer laser annealed poly-Si films on various substrate materials such as MoW, Cr,

Effects of Excimer Laser Annealing Process on the Ni-Sputtered Amorphous Silicon Film

SiO_2

P‐8: a‐Si:H TFT‐LCD with Single Organic Passivation Layer

were studied. It was found that the crystallinity of the film depended on the recrystallization energy density and substrate materials. The crystallinity of the film on