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We have demonstrated that the sequential lateral solidification (SLS) technology can be utilized for the large area AMOLED. An optimized SLS process provides us with polycrystalline Si films with well‐controlled grain size and location. The thin film transistors (TFTs) with SLS‐processed Si films show high performance with desirable uniformity. 14″ WXGA (1280×RGB×768) AMOLEDs were fabricated with SLS‐processed TFT backplanes. We utilized RGB evaporation process with fine metal mask. The novel delta pixel arrangement results in increased aperture ratio and wider FMM process window. The advantage of SLS process will be discussed.

In this paper, we review various LTPS backplane technologies based on laser-crystallization and other related methods that have been applied to AMLCD and AMOLED displays. The TFT performances obtained by different melt-mediated crystallization methods with excimer laser and solid phase crystallization will be compared. The technical issues of the image quality and the resolution will be discussed.

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organic light-emitting diode (QD-OLED) product based on an oxide thin-film transistor (TFT) using an amorphous oxide semiconductor, indium-gallium-zincoxide (a-IGZO), which it will soon release. The QD-OLED has a high color gamut (BT2020 > 90%) and has excellent advantages over liquid crystal displays (LCDs) or OLEDs (BT2020, ≈75%). In the case of blue light (415-455 nm), which is harmful to eyesight, it emits only half that of existing LCDs and ≈30% that of OLEDs, emitting the lowest level among current displays. Furthermore, QD-OLEDs exhibit the best performance in all picture quality fields, such as viewing angle, reflectivity, and contrast. [6] It is important to secure the electrical stability of oxide TFTs in order to achieve high resolution, high brightness, and long life. The TFTs of the QD-OLED with the active-matrix operation basically consist of driving TFTs and switching TFTs. In the case of driving TFTs, which always supply a constant current, electrical stability is required under constant current stress (CCS) and positive bias thermal stress (PBTS). In the case of switching TFTs with a long turn-off state, it is essential to secure the stability under negative bias thermal illumination stress (NBTIS). To date, studies on the mechanism related to electrical stability have been continuously conducted on oxide TFTs using various oxide semiconductors, such as ZnO, ZnSnO, InGaZnO, InZnSnO, ZrInZnO, etc. [2,[7][8][9][10][11][12][13][14] The oxygen vacancies or oxygen interstitial model, [15][16][17][18][19][20][21] peroxide model, [22][23][24][25][26] and hydrogen complex model [27][28][29][30][31][32][33][34][35] for the oxide semiconductor itself are proposed mechanisms for electrical instability. Furthermore, the interface and near-interface defects between the oxide semiconductor and the insulating film of the upper and lower parts of the oxide TFT are also known to cause instability. First, in the case of the oxygen vacancy model, three things are known of the energy level in the electronic structure or chemical energy (spatial coordination with cation). There is an oxygen vacancy with two trapped electrons V o 0 near the valence band, a single charged oxygen vacancy with one trapped electron V o + , and a doubly charged oxygen vacancy with no trapped electron V o 2+ near the conduction band. These oxygen defects are known to cause An amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT), which exhibits the best electrical stability (PBTS ≤ 0.009 V), is implemented to create quantum-dot organic light-emitting diode product. Electrical stability has been explained through various mechanisms involving defects related to oxygen and hydrogen. The defects of a-IGZO are identified and the parameters of the deposition process are utilized to obtain V o + and V Zn − values of 1.7 × 10 17 and 2.4 × 10 18 spins cm −3 , respectively, which are quantified using electron spin resonance for the first time. The defects of the gate insulator (GI) in the upper and lower parts of the a-IGZO TFT and ...

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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 x 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 o ) and 73 % color gamut. The advantages of SiOG technology and its significances will be presented..

We have demonstrated that thin film transistor backplanes for AMOLED could be fabricated with line‐scan sequential lateral solidification (SLS) process. with 4 μm × 730 mm single laser beamlet, directional and two‐shot SLS processes were carried out to make polycrystalline Si films. The geometry for driving TFTs, which can provide sufficient uniformity of TFT performances, is that the source‐drain direction is perpendicular to the grain growth direction. 14″ WXGA (1366×RGB×768) AMOLEDsfor TV application were fabricated by utilizing different TFT geometry for driving TFTs and switching TFTs. The advantages of the line‐scan SLS system are (1) it can provide higher productivity than the conventional laser system and (2) large displays over 50″ can be manufactured without scan overlap area.