Yuko Tachibana

High rate sputter deposition of TiO2 from TiO2−x target

Abstract A new sputter technique for high rate deposition of TiO2 was developed for applying to common planar magnetron sputter system. With this technique, using plasma sprayed TiO2−x targets and a sputter gas of a few percent of O2 diluted with Ar, TiO2 films are deposited with a high deposition rate efficiency (deposition rate per applied power density) being almost eight times larger than that of the conventional sputter method using Ti target and O2 sputter gas.

Optical properties of multilayers composed of silver and dielectric materials

We investigated the optical properties of the silver/dielectric-material multilayers and found that the absorption exists at the silver/dielectric-material interfaces. The absorption was assigned to the absorption of surface plasmon by spectral and ellipsometric analysis and X-ray photoelectron spectroscopy (XPS). The absorption was detected as the difference between the measured transmittance and the calculated one with using the optical constants of constituent layers. The absorption increases with the number of the silver/dielectric-material interfaces and with the dielectric constant of the dielectric materials. By considering the absorbing layer at the silver/dielectric-material interface, the ellipsometric analysis gives a good fit of the optical constants and thicknesses of constituent layers and the measured transmittance agrees well with the calculated one using the ellipsometrically obtained results. XPS analysis showed that the resonant energy of the surface plasmon, excited inside the silver layer but in the vicinity of the silver/dielectric-material interface, decreases with the increase of the thickness of the dielectric material and with the increase of the dielectric constant of the dielectric material. This energy shift of the surface plasmon is consistent with the optical absorption measured.

High rate deposition of TiO2 by DC sputtering of the TiO2-X target

Abstract A new sputter method for high rate deposition of TiO 2 was developed for application to the common planar magnetron sputter system. In this method, DC power is applied to plasma sprayed TiO 2− X targets using a sputter gas of a few percent of O 2 diluted with Ar and then TiO 2 films are deposited with a high deposition rate (eight times higher than that by the conventional method) and a good uniformity of thickness and refractive-index distribution.

TiO2−X sputter for high rate deposition of TiO2

Abstract A new sputter technique for high rate deposition of TiO2 was developed for applying to conventional planar magnetron DC sputter system. In this technique, TiO2 films are deposited by using a plasma-sprayed TiO2−X target and Ar sputter gas including a few percent of O2 gas. The deposition rate efficiency (deposition rate per applied power density) was almost 8 times larger than that of the conventional sputter method. This technique also has an advantage that there is no damage done to the under layer during the deposition. The Low-E coatings, being multi-stacks of Ag/TiO2, were obtained even in the case of no protective layer on Ag film and their optical properties were better than those of Low-E coatings including ZnO as the dielectric layer, because of the high refractive index of TiO2.

A new layer system of anti-reflective coating for cathode ray tubes

A new anti-reflective (AR) coating system, using an absorbing layer, has been developed for cathode ray tubes (CRTs). Theoretical analysis has revealed that the basic system needs only two layers to achieve zero reflection throughout the visible region if an ideal absorbing layer and a transparent layer are combined. The conditions for realizing the ideal AR property with two-layer system has been derived by numerical calculations. TiN x O y was chosen as the actual absorbing layer, while SiO 2 was chosen as the transparent layer. These choices are both based on theoretical and experimental considerations. The oxygen content in the TiN x O y film was found to play an important role on the AR properties, therefore a very thin (around 5 nm) SiN x barrier layer was deposited on the TiN x O y layer to prevent the oxidization of the TiN x O y during the subsequent deposition of SiO 2 . The insertion of such a thin SiN x layer was found to have almost no influence on the optical properties, therefore the system (Glass/TiN x O y /SiN x /SiO 2 ) can be called as two-layer system with a barrier layer. The AR properties and the electromagnetic shielding property (i.e. the electrical conductivity) of the coating was almost the same as the conventional transparent multilayer system which needs more than twice as thick as this system. This coating has been successfully adapted to the panel glass for CRTs on an industrial scale.

Low resistance AR stack including silver layer

Abstract A new 4-layer antireflective (AR) stack with a low sheet resistance and high transmittance has been developed. The deposited AR stack has a layer construction of 68 nm SiO 2 /9 nm ZnO:2.3 at.% Al/5 nm Ag/33 nm ZnO:2.3 at.% Al/glass and excellent AR properties, visible transmittance (85.0%), visible reflectance (0.34%) and 0.6% bandwidth ratio (1.87). Its sheet resistance is 23.3 Ω and adjustable from 16 to 30 Ω while maintaining good AR properties. Two ways to improve the chemical and mechanical durability of the AR stack were proposed; one is doping of gold into silver; the other is self-graded over-coating with fluorocarbon layer/binding layer/hydrocarbon polymer layer.

18.3: A New Layer System for Wideband Anti-Reflection Coatings Designed for CRTs

A new AR coating using an absorbing layer has been developed for CRTs. Theoretical analysis has revealed that basic layer system needs only an “ideal” absorbing layer and SiO2. A Glass/TiNxOy/SiO2 layer system made by DC reactive sputtering exhibited wideband anti-reflection property as well as Iow sheet resistance comparable to conventional transparent multi-layer stacks. SiNx barrier layer inserted between TiNxOy and SiO2 layers made it durable against the heat treatment during CRT manufacturing process, which realized the commercialization of coated panel glass for CRTs with this layer system.

Bendable and temperable solar control glass

Abstract Bendable and temperable solar control glass with a basic layer construction of SnO 2 /SiN x /CrN x /SiN x /SnO 2 was produced by the dc reactive sputtering method. For protection of the CrN x layer from oxidation during heat treatment processes, thin buffer layers of SiN x were inserted between the CrN x layer and oxygen sources such as air and SnO 2 layers. It was found that the stoichiometric Si 3 N 4 with a minimum of impurities is a good buffer layer. The SnO 2 layer deposited on the transition mode indicated the lower oxygen diffusion coefficient and oxygen release property than one deposited on an oxide mode. The transition mode SnO 2 has, therefore, been proved to be suitable for the bendable and temperable solar control glass.