Nickel oxide morphology synthesized with a hydrothermal method for inverted perovskite solar cells.

In this paper, a hydrothermal method is used to synthesize a nickel oxide nanostructure (nano-NiO) for its application to inverted perovskite solar cells. These pore nanostructures were employed to increase both the contact and channel between the hole transport and perovskite layers of an ITO/nano-N i O/C H 3 N H 3 P b I 3/P C B M/A g device. The purpose of this research is twofold. First, three different nano-NiO morphologies were synthesized at temperatures of 140°C, 160°C, and 180°C. Then, a Raman spectrometer was used to check the phonon vibration and magnon scattering characteristics after an annealing temperature of 500°C. Second, nano-NiO powders were dispersed in isopropanol for subsequent spin coating on the inverted solar cells. The nano-NiO morphologies were multi-layer flakes, microspheres, and particles at synthesis temperatures of 140°C, 160°C, and 180°C, respectively. When the microsphere nano-NiO was used as the hole transport layer, the perovskite layer had a larger coverage of 83.9%. The grain size of the perovskite layer was analyzed by x-ray diffraction, and strong crystal orientations of (110) and (220) peaks were found. Despite this, the power conversion efficiency could affect the promotion, which is 1.37 times higher than the poly(3,4-ethylenedioxythiophene) polystyrene sulfonate element conversion efficiency of the planar structure.

Reusable TiN Substrate for Surface Plasmon Resonance Heterodyne Phase Interrogation Sensor.

A TiN-based substrate with high reusability presented high-sensitivity refractive index measurements in a home-built surface plasmon resonance (SPR) heterodyne phase interrogation system. TiN layers with and without additional inclined-deposited TiN (i-TiN) layers on glass substrates reached high bulk charge carrier densities of 1.28 × 1022 and 1.91 × 1022 cm-3, respectively. The additional 1.4 nm i-TiN layer of the nanorod array presented a detection limit of 6.1 × 10-7 RIU and was higher than that of the 46 nm TiN layer at 1.2 × 10-6 RIU when measuring the refractive index of a glucose solution. Furthermore, the long-term durability of the TiN-based substrate demonstrated by multiple processing experiments presented a high potential for various practical sensing applications.

Characterization of silicon oxynitride films deposited by a high-power impulse magnetron sputtering deposition technique.

In this research, silicon oxynitride films were prepared by high-power impulse magnetron sputtering with 45/955 pulse on/off time. The extinction coefficient was smaller than 1×10-3 from 250 to 700 nm after introducing 2.2 sccm O2 gas at room temperature. A three-layer of AlF3/SiOxNy AR coating was designed and fabricated on double-sided quartz, and a high transmittance of 99.2% was attained at 248 nm. The silicon oxynitride films deposited at 350°C had the better mechanical and optical properties in the visible range. The hardness of all deposited films was greater than 19 GPa, and the greatest hardness could reach to 29.8 GPa. A film structure of six-layer transparent hard coating/glass/four-layer AR coating was designed and deposited. Its average transmittance was 96.0% in the visible range, while its hardness was 21 GPa and its surface roughness was 0.23 nm.

Growth of Gold Dendritic Nanoforests on Titanium Nitride-coated Silicon Substrates.

In this study, a high-power impulse magnetron sputtering system is used to coat a flat and firm titanium nitride (TiN) film on silicon (Si) wafers, and a fluoride-assisted galvanic replacement reaction (FAGRR) is employed for the rapid and easy deposition of gold dendritic nanoforests (Au DNFs) on the TiN/Si substrates. Scanning electron microscopy (SEM) images and energy-dispersive X-ray spectroscopy patterns of TiN/Si and Au DNFs/TiN/Si samples validate that the synthesis process is accurately controlled. Under the reaction conditions in this study, the thickness of the Au DNFs increases linearly to 5.10 ± 0.20 µm within 15 min of the reaction. Therefore, the employed synthesis procedure is a simple and rapid approach for preparing Au DNFs/TiN/Si composites.

A facile approach to prepare silicon-based Pt-Ag tubular dendritic nano-forests (tDNFs) for solar-light-enhanced methanol oxidation reaction.

In this paper, a facile two-step Galvanic replacement reaction (GRR) is proposed to prepare Pt-Ag tubular dendritic nano-forests (tDNFs) in ambient condition for enhancing methanol oxidation reaction (MOR) under solar illumination. In the first GRR, a homogeneous layer of silver dendritic nano-forests (DNFs) with 10 µm in thickness was grown on Si wafer in 5 min in silver nitride (AgNO3) and buffer oxide etchant (BOE) solution. In the second GRR, we utilized chloroplatinic acid (H2PtCl6) as the precursor for platinum (Pt) deposition to further transform the prepared Ag DNFs into Pt-Ag tDNFs. The catalytic performance and solar response of the Pt-Ag tDNFs toward methanol electro-oxidation are also studied by cyclic voltammetry (CV) and chronoamperometry (CA). The methanol oxidation current was boosted by 6.4% under solar illumination on the Pt-Ag tDNFs due to the induced localized surface plasmon resonance (LSPR) on the dendritic structure. Current results provide a cost-effective and facile approach to prepare solar-driven metallic electrodes potentially applicable to photo-electro-chemical fuel cells.

Head-up display using an inclined Al2O3 column array.

An orderly inclined Al2O3 column array was fabricated by atomic layer deposition and sequential electron beam evaporation using a hollow nanosphere template. The transmittance spectra at various angles of incidence were obtained through the use of a Perkin-Elmer Lambda 900 UV/VIS/NIR spectrometer. The inclined column array could display the image information through a scattering mechanism and was transparent at high viewing angles along the deposition plane. This characteristic of the inclined column array gives it potential for applications in head-up displays in the automotive industry.

FTO films deposited in transition and oxide modes by magnetron sputtering using tin metal target.

Fluorine-doped tin oxide (FTO) films were prepared by pulsed DC magnetron sputtering with a metal Sn target. Two different modes were applied to deposit the FTO films, and their respective optical and electrical properties were evaluated. In the transition mode, the minimum resistivity of the FTO film was 1.63×10(-3) Ω cm with average transmittance of 80.0% in the visible region. Furthermore, FTO films deposited in the oxide mode and mixed simultaneously with H2 could achieve even lower resistivity to 8.42×10(-4) Ω cm and higher average transmittance up to 81.1% in the visible region.

Improving optical properties of silicon nitride films to be applied in the middle infrared optics by a combined high-power impulse/unbalanced magnetron sputtering deposition technique.

Silicon nitride films are prepared by a combined high-power impulse/unbalanced magnetron sputtering (HIPIMS/UBMS) deposition technique. Different unbalance coefficients and pulse on/off ratios are applied to improve the optical properties of the silicon nitride films. The refractive indices of the Si3N4 films vary from 2.17 to 2.02 in the wavelength ranges of 400-700 nm, and all the extinction coefficients are smaller than 1×10(-4). The Fourier transform infrared spectroscopy and x-ray diffractometry measurements reveal the amorphous structure of the Si3N4 films with extremely low hydrogen content and very low absorption between the near IR and middle IR ranges. Compared to other deposition techniques, Si3N4 films deposited by the combined HIPIMS/UBMS deposition technique possess the highest refractive index, the lowest extinction coefficient, and excellent structural properties. Finally a four-layer coating is deposited on both sides of a silicon substrate. The average transmittance from 3200 to 4800 nm is 99.0%, and the highest transmittance is 99.97% around 4200 nm.

Fluorine-doped tin oxide films grown by pulsed direct current magnetron sputtering with an Sn target.

Fluorine-doped tin oxide (FTO) films have been deposited by pulsed DC magnetron sputtering with an Sn target. Various ratios of CF4/O2 gas were injected to enhance the optical and electrical properties of the films. The extinction coefficient was lower than 1.5×10(-3) in the range from 400 to 800 nm when the CF4O2 ratio was 0.375. The resistivity of fluorine-doped SnO2 films (1.63×10(-3) Ω cm) deposited at 300 °C was 27.9 times smaller than that of undoped SnO2 (4.55×10(-2) Ω cm). Finally, an FTO film was consecutively deposited for protecting the oxidation of indium tin oxide films. The resistivity of the double-layered film was 2.68×10(-4) Ω cm, which increased by less than 39% at a 450 °C annealing temperature for 1 h in air.

Antireflection coatings for deep ultraviolet optics deposited by magnetron sputtering from Al targets.

We introduce an innovative technique for the deposition of fluorine doped oxide (F:Al(2)O(3)) films by DC pulse magnetron sputtering from aluminum targets at room temperature. There was almost no change in transmittance even after the film was exposed to air for two weeks. Its refractive index was around 1.69 and the extinction coefficient was smaller than 1.9 × 10(-4) at 193 nm. An AlF(3)/F:Al(2)O(3) antireflection coating was deposited on both sides of a quartz substrate. A high transmittance of 99.32% was attained at the 193 nm wavelength. The cross-sectional morphology showed that the surface of the multilayer films was smooth and there were no columnar or porous structures.

Developing new manufacturing methods for the improvement of AlF3 thin films.

In this research, the plasma etching mechanism which is applied to deposit AlF(3) thin films has been discussed in detail. Different ratios of O(2) gas were injected in the sputtering process and then the optical properties and microstructure of the thin films were examined. The best optical quality and smallest surface roughness was obtained when the AlF(3) thin films were coated with O(2):CF(4) (12 sccm:60 sccm) at 30 W sputtering power. To increase the deposition rate for industrial application, the sputtering power was increased to 200 W with the best ratio of O(2)/CF(4) gas. The results show that the deposition rate at 200W sputtering power was 7.43 times faster than that at 30 W sputtering power and the extinction coefficients deposited at 200 W are less than 6.8 x 10(-4) at the wavelength range from 190 nm to 700 nm. To compare the deposition with only CF(4) gas at 200 W sputtering power, the extinction coefficient of the thin films improve from 4.4 x 10(-3) to 6 x 10(-4) at the wavelength of 193 nm. In addition, the structure of the film deposited at 200W was amorphous-like with a surface roughness of 0.8 nm.

Fluoride antireflection coatings deposited at 193 nm.

Antireflection coatings for 193 nm composed of low-index (MgF(2) and AlF(3)) and high-index (LaF(3) and GdF(3)) materials are deposited by the resistive heating boat method at a substrate temperature of 300 degrees C. The optical characteristics (reflectance and optical loss), microstructure (morphology and surface roughness), stress, and laser-induced damage threshold (LIDT) of the coatings are investigated and discussed. The related reflection at 193 nm of the four kinds of antireflection coatings is smaller than 0.2% and the optical loss is less than 0.15%. Of the fluoride antireflection coatings, AlF(3)/GdF(3) had the lowest stress value. Antireflection coatings with AlF(3) as the low-index material had higher LIDT values than when MgF(2) was used.

Residual stress in obliquely deposited MgF2 thin films.

MgF(2) films with a columnar microstructure are obliquely deposited on glass substrates by resistive heating evaporation. The columnar angles of the films increases with the deposition angle. Anisotropic stress does not develop in the films with tilted columns. The residual stresses in the films depend on the deposition and columnar angles in a columnar microstructure.

Process for deposition of AlF3 thin films.

We fabricated aluminum fluoride (AlF(3)) thin films by pulsed DC magnetron sputtering with various CF(4) flow rates and sputtering powers. Our method is distinct from the conventional deposition process in that we used inexpensive Al (99.99% purity) as the target instead of an expensive fluoride compound. The optical properties and microstructure of the thin films were examined. The optical quality of AlF(3) thin films deposited at a 20 W sputtering power and injected 110 SCCM (SCCM denotes cubic centimeters per minute at standard temperature and pressure) CF(4) flow at room temperature showed improvement with an extinction coefficient of less than 7 x 10(-4) at 193 nm. The deposition of AlF(3) thin films at different substrate temperatures and annealed by UV light was also investigated.

AlF(3) thin films deposited by reactive magnetron sputtering with Al target.

Aluminum fluoride thin films have been deposited by magnetron sputtering of an aluminum target with CF(4) , and CF(4) mixed O(2) as the working gas onto a room temperature substrate. The quality of the coated AlF(3) film applied with 25W sputtering power using CF(4) mixed 5% O(2) was better than for films deposited using conventional methods. The extinction coefficient of AlF(3) was smaller than 6.0x10(-4) in the wavelength range of 190nm to 250nm. Single layer antireflection coatings on both sides of a fused silica substrate increased the transmittance from less than 91% for a bare substrate to higher than 96% in the wavelength range between 190nm to 250nm.