Brian T. Sullivan

High-rate automated deposition system for the manufacture of complex multilayer coatings.

A previously described automated thin-film deposition system based on rf-magnetron sputtering could deposit quite complex optical multilayer systems with good precision and with no one in attendance [Sullivan and Dobrowolski, Appl. Opt. 32, 2351-2360 (1993)]. However, the deposition rate was slow, and the uniform area on the substrate was limited. We describe an ac-magnetron sputtering process in which the same deposition accuracy has been combined with significantly better film uniformity and a fivefold or sevenfold increase in the deposition rate. This makes the equipment of commercial interest. Experimental results are presented for several difficult coating problems.

Optical properties and microstructure of reactively sputtered indium nitride thin films

The optical properties of reactively sputtered InN thin films were measured in the spectral region 2.5–5.5 eV using spectroscopic ellipsometry. The measured pseudodielectric function data of the InN films were found to vary with deposition power. The effective medium approximation theory, which describes a random aggregate microstructure, was able to relate the differences in the measured optical properties to the surface microroughness and porosity of the InN films. The relationship between microstructure and deposition power was subsequently verified by scanning electron microscopy. The analysis and electron microscopy indicate that the film deposited at 90 W was most representative of InN.

Bi-Sr-Ca-Cu-oxide superconducting thin films deposited by dc magnetron sputtering

Thin films of the high‐temperature superconductor Bi‐Sr‐Ca‐Cu‐oxide were deposited by dc magnetron sputtering onto various substrates. Films deposited on (100) MgO substrates achieved zero resistance between 78 and 82.5 K depending upon the annealing conditions. The best films were produced with a quick post‐anneal in oxygen at 870 °C followed by a slower anneal in air at the same temperature. The composition of the sputtered films was uniform within ±3% over an area 40 mm in radius, and films deposited at 15 and 40 mm from the center of deposition both exhibited high Tc transitions.

Use of the 4 × 4 matrix method in the optics of multilayer magnetooptic recording media

The new 4x4 matrix method described by Lin-Chung and Teitler [P. J. Lin-Chung and S. Teitler, J. Opt. Soc. Am. A 1, 703 (1984)] is used to study the optics of multilayer magnetooptic recording media. It is demonstrated that the method is capable of handling very complicated optical multilayer structures. For a quodrilayer magnetooptic recording system consisting of an overcoat layer, a magnetic layer, an intermediate dielectric layer, and a reflector, the readout of the system is optimized against the thickness of the overcoat and intermediate layers. As well, cases of oblique angle of incidence, anisotropy in the nonmagnetic part of the dielectric constants, and misalignment of the magnetization are treated.

Investigation of d.c. planar-magnetron-sputtered palladium films by spectroscopic ellipsometry☆

Abstract The pseudodielectric function of palladium films prepared by d.c. planar magnetron sputtering was measured by spectroscopic ellipsometry as a function of substrate temperature. The film data are in excellent agreement with an optical model using the Sen, Scala and Cohen effective medium theory, which is based on a dielectric coated-particle microstructure. With increasing substrate temperature, the palladium volume fraction was found to decrease slightly, while the r.m.s. microroughness of the film surface increased in magnitude. For temperatures below 115°C the film microstructure was not significantly affected by the substrate temperature but, by 190°C, the r.m.s. microroughness was 80±3A, with the palladium volume fraction in the bulk region falling slightly to 97%±1% relative to the film deposited at 22°C. These results are compared with those obtained by electron microscopy and X-ray diffraction.

J. A. Dobrowolski (1931–2013): in memoriam

J. A. Dobrowolski, or George, as he was known to his friends and colleagues, passed away on February 12, 2013 in Ottawa, Ontario. George was a leading pioneer in the field of optical thin films. His work stretched over 60 years beginning with his graduate studies in 1953, and he impacted all areas of research in this field. This in memoriam outlines both his professional career and personal life; as befitting George, there is a comprehensive list of his numerous publications in books, papers, and patents. An in memoriam talk on Georges life and career was presented at the 2013 Optical Interference Coatings Conference held in Whistler, B.C., Canada on June 16-21, 2013.

RF magnetron sputtering of high‐Tc Bi‐Sr‐Ca‐Cu‐O thin films

Thin films of Bi‐Sr‐Ca‐Cu‐O were produced by RF magnetron sputtering onto single crystal (100) MgO substrates. Substrate temperature and deposition atmosphere were found to affect the thickness and composition of as‐deposited films. Subsequent annealing of the films resulted in highly oriented superconductors, which were usually multiphase with 2223, 2212, and 2201 phases. Film properties were highly dependent on annealing conditions.

Optical interference coatings: eighth topical meeting

A brief account is given of the Eighth Optical Society of America Topical Meeting on Optical Interference Coatings held 15–20 July 2001 in Banff, Alberta, Canada. Photographs of some attendees are appended.