Chunya Wu

Room-temperature deposition of thin-film indium tin oxide on micro-fabricated color filters and its application to flat-panel displays

— Direct deposition of indium tin oxide (ITO) thin film on color filters is of practical use in the fabrication of state-of-the-art flat-panel displays. Room-temperature dc magnetron sputtering of thin-film ITO and issues related to the integration of ITO-on-glass panels containing micro-fabricated color filters and other functional materials have been investigated. The resulting polycrystalline ITO exhibited good adhesion to the underlying color filters, as well as good optical transparency and high electrical conductivity. Application of this ITO deposition technology to color liquid-crystal and organic light-emitting diode displays will also presented.

35.4: A 2.1-inch AMOLED Display Based on Metal-Induced Laterally Crystallized Polycrystalline Silicon Technology

A 2.1-inch color active-matrix organic light-emitting diode display based on an improved metal-induced laterally crystallized polycrystalline silicon technology is demonstrated. Leakage current was reduced with the active islands of polycrystalline silicon transistors patterned after nickel-based metal-induced lateral crystallization. Color was obtained by combining whitelight organic light-emitting diodes with micro-fabricated color filters.

P-60: The Performance Enhancement of the 2ωYAG Laser-Crystallized Poly-Si Using a Back-side Self-Heating Layer of a-Si

Crystallization of a-Si by doubled frequency YAG laser using a self-heating layer technology was proposed in this paper. The grain size and the hall mobility of the resulted poly-Si thin film were enhanced up to almost two times by using the self-heating layer technology. This technology has a dual heating effect: heat-retaining and self-heating with an easier process and wider process window, compared to the conventional capping-layer technology.

The μc-Si on plastic substrate crystallized by pulsed double-frequency YAG laser annealing

Microcrystalline silicon (μc-Si) thin film transistors (TFTs) can be provided with higher mobility and stability than a-Si and better uniformity than poly-Si TFTs, it would be more suitable to be applied in larger area AMOLED. By using 2ωYAG laser annealing, crystalline μc-Si thin film on plastic substrate has been investigated and the proper laser energy needed for crystallization has been indicated. It has been found that the dehydrogenation process at 300~450 °C for a few of hours could be omitted by decreasing the H content in the crystallization precursor, which is suitable for laser crystallization on plastic substrate. The crystalline volume fraction (Xc) and the grain size of the resulted μc-Si could be adjusted by controlling the laser energy. By this method, the μc-Si on plastic substrate with the Xc and the grain size are 85% (at the maximum) and 50nm respectively has been achieved.

Research on the fabrication of μc-Si and its incubation layer

Research on the fabrication of μc-Si used as the active layer of TFT and the incubation-layer of μc-Si is presented in this paper. VHF-PECVD is used to fabricate μc-Si film since the μc-Si can be fabricated with a higher growth rate than RF-PECVD. The amorphous incubation-layer between the substrate and the μc-Si layer can be thinned effectively by increasing hydrogen dilution. In addition, to obtain good TFT performance, the growth rate should be appropriate resulting in relative large grain size.

Numerical Simulation of the Influence of the Gap State of a-Si:H on the Characteristics of a-Si:H p-i-n/OLED Coupling Device

The influence of the density of gap states and the band gap width of the intrinsic a-Si:H active layer on the characteristics of a-Si PIN/OLED coupling pair was analyzed by a-Si:H PIN/OLED CAD simulation model. The CAD simulation model was carried out based on a-Si PIN Hack & Shur model and OLED TCL transport model. At the same band gap width, for the intrinsic a-Si:H active layer with the higher density of gap states, the reverse current of a-Si PIN trended to be saturated at the higher reverse bias voltage. As a result, I-V curve of a-Si PIN/OLED around the turn point Vt became smoother with the increase of the density of gap states. At the same state density, the light induced current of a-Si PIN increased against the band gap width, assuming the input light had the same spectrum as AM1.5 solar light. Thus the luminance emitted from OLED increased with the decrease of the band gap width because OLED belongs to the light-emitting device controlled by current. The simulation results also showed that the influence of the state density intensified with the increase of the band gap of a-Si:H.