Superior Transmittance Research Articles

Comparison of AZO, GZO, and AGZO Thin Films TCOs Applied for a-Si Solar Cells

This study prepared aluminum and gallium co-doped zinc oxide (AGZO) thin films using pulsed direct current magnetron sputtering, and studied the electrical properties, transmittance, effects of texturing, and applicability as the front contact for a-Si:H solar cells. Textured ZnO:Al (AZO) and ZnO:Ga (GZO) thin films were also compared with AGZO thin film to evaluate their performance as front contacts. Experimental results show that AGZO films with the highest figure of merit ϕTC value (24.64 × 10−3 Ω−1) were obtained at Al and Ga doping concentrations of 0.54 wt% and 1.165 wt%, respectively. The textured AGZO films used as the front contact in a-Si:H solar cells achieved the following results: VOC = 0.77 V, JSC = 16.5 mA/cm2, FF = 59%, and conversion efficiency of 7.53%. AZO and GZO films have better electrical properties than AGZO film; however, AGZO film has superior transmittance in the near-infrared (NIR) region and higher JSC, conversion efficiency and external quantum efficiency (EQE) than AZO and GZO films under a similar haze value.

Innovative elastic and flexible conductive PEDOT:PSS composite films prepared by introducing soft latexes

Innovative elastic and flexible conductive composite materials PEDOT:PSS/P(BA–St) and PEDOT:PSS–PBA were prepared by two approaches based on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). In the first part, PEDOT:PSS/P(BA–St) was prepared by blending various soft poly(n-butyl acrylate–styrene) (P(BA–St)) latexes into a PEDOT:PSS conductive dispersion. The PEDOT:PSS conductive dispersion was prepared via oxidative polymerization of EDOT, and the soft P(BA–St) latexes were synthesized by emulsion polymerization using various types of surfactants. In the second part, poly(styrenesulfonate) (PSS) served as a surfactant to synthesize poly(styrenesulfonate)–poly(butyl acrylate) (PSS–PBA) soft latex viaemulsion polymerization. Then, the PEDOT:PSS–PBA dispersion was prepared by using the PSS–PBA soft latex as a polymeric template to polymerize EDOT. The glass transition temperature (Tg) and particle size of P(BA–St) and PSS–PBA were measured. The optoelectronic properties of the conductive PEDOT:PSS/P(BA–St) and PEDOT:PSS–PBA films such as transmittance, surface resistance, and UV-vis absorbance were investigated. According to the elongation measurement, the fabricated PEDOT:PSS/P(BA–St) elastic film containing a P(BA–St) content as high as 83 wt% showed a high value of 97% elongation, while possessing good film conductivity (63 S cm−1) and superior transmittance (93%). On the other hand, the fabricated PEDOT:PSS–PBA flexible film containing 13 wt% PBA showed a low surface resistance increment (R/R0 80%).

A new vertical‐alignment LC mode with high‐transmittance and fast‐response‐time features

Abstract— A novel pixel design for vertical‐alignment LCDs with superior transmittance has been developed. The new liquid‐crystal mode, refered to as the hole‐induced vertical‐alignment mode (Hi‐VA), uses a via hole of an organic layer on a TFT substrate to achieve multi‐domain alignment. Compared to the conventional design, the Hi‐VA mode has a transmittance of up to 135% with a contrast ratio of 2000:1. Moreover, the new structure is free from ITO patterning or protrusion on the color‐filter side, which makes the fabrication process simple and low cost.

48.3: Distinguished Paper: A Novel Hole Induced Vertical Alignment LC Mode with Superior Transmittance

AbstractA novel pixel design for vertical alignment LCD with superior transmittance is developed in this work. The new liquid crystal mode, named as Hole Induced Vertical Alignment mode (Hi‐VA), uses a via hole of an organic layer on TFT substrate to achieve multi domain alignment. Compare to conventional design, the Hi‐VA mode has up to the transmittance of 135% with the contrast ratio of 2000:1. Moreover, the new structure is free from the ITO patterning or protrusion on color filter side, which makes the fabrication process simple and low cost.

Preparation of SiO2 Nanotubes with Controllable Inner/Outer Diameter and Length Using Hydrothermally Grown ZnO Nanowires as Templates

Through the deposition of a thin SiO2 film to sheathe hydrothermally grown (HTG) ZnO nanowires (ZnO-NWs), unveiling their top portion, and then selectively removing ZnO-NWs by wet chemical etching, SiO2 nanotubes (SiO2-NTs) with controllable inner/outer diameters and lengths were fabricated. The prepared SiO2-NTs with average inner/outer diameters and lengths of approximately 200/300 nm and 1.5 µm, respectively, exhibited a superior transmittance of 92% in the visible light spectrum. The surface roughened process using SiO2-NTs on vertical-structure GaN light-emitting diodes (VLEDs) showed additional light output improvement of about 11.6% at 350 mA and 10% at 750 mA, compared with those of VLEDs with ZnO-NWs, suggesting the effectiveness and promising applications of the proposed SiO2-NTs in optics and optoelectronics devices.

Transparent, conductive carbon nanotube films.

We describe a simple process for the fabrication of ultrathin, transparent, optically homogeneous, electrically conducting films of pure single-walled carbon nanotubes and the transfer of those films to various substrates. For equivalent sheet resistance, the films exhibit optical transmittance comparable to that of commercial indium tin oxide in the visible spectrum, but far superior transmittance in the technologically relevant 2- to 5-micrometer infrared spectral band. These characteristics indicate broad applicability of the films for electrical coupling in photonic devices. In an example application, the films are used to construct an electric field-activated optical modulator, which constitutes an optical analog to the nanotube-based field effect transistor.