Study on controllable LC-micro blazed grating beam deflector in free space

Sputtered transparent electrodes for optoelectronic devices: Induced damage and mitigation strategies

Low-molecular weight polydimethylsiloxane, a versatile performance enhancer for the solution processed indium tin oxide transparent electrode

Flexible optoelectronic devices have a broad application prospect in the field of wearable electronic devices, among which the superior transparent electrode is the core problem in achieving high-performance flexible optoelectronic devices. The brittle indium tin oxide (ITO) transparent electrode, which is currently commonly used, is difficult to be compatible with the flexible substrate. Multilayer dielectric/metal/dielectric (DMD) structure films are attracting attention as next-generation ITO-free electrodes. High optical transmittance, super electrical conductivity, and mechanical flexibility of DMD electrodes make them promising for highly efficient optoelectronic devices. Despite substantial research on the optimization of DMD electrodes, a large gulf still exists in obtaining foldable and transparent conductive electrodes and applying them to light-emitting devices, including organic light-emitting diodes (LEDs), quantum dot LEDs, and perovskite LEDs. In this perspective, we review the superiority of DMD electrodes in terms of optical and electrical performance, and mechanical flexibility, and summarize their applications in LEDs. Furthermore, we also give future research directions for DMD electrodes regarding physical properties, mechanism stability, and application reliability.

Welded silver nanowire networks as high-performance transparent conductive electrodes: Welding techniques and device applications

Indium tin oxide (ITO) transparent electrodes are troubled with high cost and poor mechanical stability. In this study, layer-by-layer (LBL)-processed thin films with single-walled carbon nanotubes (SWNTs) exhibited high transparency and electrical conductivity as a candidate for ITO replacement. The repetitive deposition of polycations and stabilized SWNTs with a negative surfactant exhibits sufficiently linear film growth and high optoelectronic performance to be used as transparent electrodes for vertically aligned (VA) liquid crystal display (LCD) cells. The LC molecules were uniformly aligned on the all of the prepared LBL electrodes. VA LCD cells with SWNT LBL electrodes exhibited voltage-transmittance (V-T) characteristics similar to those with the conventional ITO electrodes. Although the response speeds were slower than the LCD cell with the ITO electrode, as the SWNT layers increased, the display performance was closer to the LCD cells with conventional ITO electrode. This work demonstrated the good optoelectronic performance and alignment compatibility with LC molecules of the SWNT LBL assemblies, which are potential alternatives to ITO films as transparent electrodes for LCDs.

This paper reports on a complementary investigation of the structural and opto-electronic characteristics of top-emitting organic light-emitting diodes (OLEDs). The key point of such a procedure is the deposition of the indium tin oxide (ITO) transparent top electrode onto the organic films structure. This was achieved by RF sputtering under soft enough conditions so as to avoid any deterioration of the underlying organic layers (room temperature deposition, low plasma power density and minimal bombardment effect) as much as possible. The electrical and optical properties of ITO as a function of the deposition conditions are described first. Hall effect measurements show that ITO films can be grown at room temperature with a high mobility (40 cm2 V−1 s−1) and a carrier density exceeding 5 × 1020 cm−3. The surface roughness as a function of the plasma conditions was determined by AFM and can be as low as 1.2 nm. Hole only silicon/Al/poly(N-vinylcarbazole) (PVK)/poly(3,4)ethylenedioxythiophene (PEDOT)/sputtered ITO diodes were processed and characterized both structurally (high resolution TEM in cross section) and electrically. An excellent agreement between the interfacial ITO/PEDOT structure and the hole injection performance was evidenced. Glass/ITO/PEDOT/PVK/Alq/BCP/ITO top-emitting OLED were processed and characterized.

High-performance flexible transparent conductive tape based on copper nanowires

In this work, Organic Light-Emitting Diodes (OLEDs) based on Europium (III) complex were studied, especially those with an oxygen plasma surface treatment onto indium tin oxide (ITO) transparent electrode. An OLED with the same thin-film structure but with untreated ITO was fabricated for comparison purposes. Current density-voltage characteristics for treated devices demonstrated an increase from 0.4 to 3.3 mA/cm² and a decrease of the turn-on voltage from 28 to 22 V. Additionally, improved hole injection through the transparent electrode impacted on optical response, as luminous efficiency increased from 26 to 44 mcd/A with the advantage of no significant disturb on the europium typical electroluminescence emission spectrum. Emission peak was observed at a wavelength of approximately 614 nm, which is defined by the transition associated with spectroscopic terms (5D0→7D2) and CIE chromaticity coordinates of (0.50;0.36).

Changes in the q-Φ-n distribution of partial discharge (PD) generated by a simulated defect structure have conventionally been investigated to determine the degree of partial discharge degradation of resin or resin composite materials due to long-term application of voltage. The purpose of this study is to analyze the relationship between the change in the q-Φ-n distribution and of that in the discharge state occurring inside the defect. A spherical electrode/ polyethyleneterephthalate (PET)/ cylindrical void/ PET/flat plate electrode system was employed as an artificial defect structure, and an Indium tin oxide (ITO) transparent electrode was used as a flat plate electrode to enable direct observation of the light emissions during the occurrence of partial discharge. The observations of changes in the q-Φ-n distribution and the discharge state occurring inside the defects are presented in this paper. Furthermore, the mechanism of resin degradation is discussed based on the observation results of resin surfaces exposed to partial discharge for a long term. We found that the degradation of PET surface progressed faster when the PD was sustained at the protruding structure, which is a PD byproduct.

In this paper, Prussian Blue (PB) thin films were deposited on indium Tin Oxide (ITO) transparent electrode using electro-deposition technique. The films are easily prepared by successive immersion of the substrates into an aqueous solution of FeCl3 and K4[Fe(CN)6]. The effect of the molar concentration during deposition process of the films is studied. The prepared films were subjected to electrochemical ion insertion using electrochemical cell containing 1M KCl aqueous solution. The electrochromic properties of samples prepared at different conditions were studied by transmittance and reflectance measurements. Films prepared at concentration of 0.04 and 0.05 possess a good electrochromic properties (Tv = 0.32 and OD = 0.28). However, films prepared at higher solution concentrations possess a low dynamic range (e.g. sample (M5) has Tv = 0.05 and OD = 0.07). X-ray diffraction show that the film prepared at a solution concentration of 0.04 which possess a good electrochromic properties is in the amorphous state. Also, SEM analysis shows that the sample prepared at a solution concentration of 0.04 has a small grain diameter (43nm).

A study of stitch line formation during high speed laser patterning of thin film indium tin oxide transparent electrodes

Transparent electronics is a burgeoning field with exciting potential for next‐generation “see‐through” devices. The creation of high‐performance fully transparent ultraviolet photodetectors (PDs) is essential for enabling wearable and portable applications. In this study, metal–semiconductor–metal (MSM) type Al‐doped ZnO (AZO)/GaN/AZO and indium tin oxide (ITO)/GaN/ITO‐transparent ultraviolet PDs, are initially designed, utilizing AZO‐ and ITO‐transparent conductive electrodes. In these investigations, it is revealed that AZO and ITO form Ohmic and Schottky contacts, respectively, with GaN. Subsequently, building on these findings, a fully transparent Schottky barrier photodiode (SBPD) is developed for ultraviolet photodetection using AZO/GaN/ITO. The SBPD displays a high responsivity (R) of 1.41 × 103 A W−1, a detectivity (D*) of 6.85 × 1014 Jones, and a photo‐to‐dark current ratio exceeding 1 × 104 at a − 5 V bias. Furthermore, the SBPD demonstrates an ultrahigh responsivity of 1.18 A W−1 at 0 V bias, indicating its potential as a self‐powered device under extreme conditions. In these results, the tremendous potential of the high‐performance and fully transparent GaN‐based SBPD is demonstrated for environmental monitoring, optical communication, military radar, and other fields.

High transparency and low sheet resistance flexible conductive electrode is of great interest to research communities working on applications such as solar cells and light emitting diodes. For this purpose, Au-decorated graphene-single wall carbon nanotube (SWCNT) thin films are developed and characterized in this work. Initially, the SWCNT is spin-coated on a Cu foil. It is then placed in thermal chemical vapor deposition machine for graphene synthesis. The film is then transferred onto an appropriate substrate. Immersion in AuCl 3 decorates the film with Au nanoparticles. Optical and electrical characterizations show that the film retains the high graphene transmittance of ∼95% and exhibits a much lower sheet resistance of ∼100 ohm/sq, respectively. Figure of merit is then defined and it shows that the hybrid film is at par with indium tin oxide (ITO) transparent conductive electrode (TCE). This suggests that the hybrid film could be applied as TCE and potentially be used in flexible applications.

Near-field electroluminescence probe of polymer light-emitting diodes

Boron-doped zinc oxide thin films grown by metal organic chemical vapor deposition for bifacial a-Si:H/c-Si heterojunction solar cells