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The International Conference on Thin Films is the most established conference for all researchers and persons interested in thin films and coatings. It is one of the tri-annual conference series endorsed and co-organized by the Thin Film Division of the International Union for Vacuum Science, Technique and Applications (IUVSTA), a union of national member societies whose role is to stimulate international collaboration in the fields of vacuum science, techniques and applications and related multi-disciplinary topics including solid-vacuum and other interfaces. The 15th International Conference on Thin Films (ICTF-15) is organized by The Vacuum Society of Japan (VSJ) and held at Kyoto TERRSA in Kyoto, Japan on 8–11 November 2011, following the 14th International Conference on Thin Films (ICTF-14), which was held in Ghent, Belgium in 2008. Thin films and coatings are daily becoming increasingly important in the fields of various industries. This International Conference provides a multi-disciplinary forum for recent advances in basic research, development and applications of thin films and coatings. This conference will present a unique opportunity for researchers, engineers and managers to acquire new knowledge of thin films and coatings. We hope that our understanding on thin films and coatings will be deepened through this conference. The conference site, 'Kyoto TERRSA' is located in the historical heart of the old capital Kyoto. Kyoto is an ancient city with a 1200-year history. It was established as Japan's capital under the name 'Heian-kyo' in the year 794. Although many transformations have taken place over the years, Kyoto has always embraced the most advanced standards of the times. It has greatly contributed to the nation's industrial, economic and cultural development. The dauntless spirit of leadership of Kyoto's past as a capital city is still felt here today. Kyoto also preserves the beloved examples of its culture as testimonials of time. This is shown in the ancient temples and shrines, as well as private houses, which are built in styles unique to Kyoto. Furthermore, many festivals, ceremonies and traditional activities reveal the will of this city to convey and develop its 1200-year-old culture. Participants of the conference will also be able to see many world heritage sites in the city. Moreover, November is the best time of year to visit Kyoto. We hope you will enjoy Kyoto very much. We would like to offer our thanks for all the contributions from the members of the International Advisory Committee and Organizing Committee, Symposium Chairs, the Secretary General, the Thin Film Division of IUVSTA (chair: Professor Dr Alberto Tagliaferro), IUVSTA, VSJ and other cooperating societies, and to all of the supporting organizations and enterprises. We would also like to express our thanks to all of the participants, secretariat members and members of the supporting staff. I am very pleased to welcome you to ICTF-15 and Kyoto! Director Professor Dr Osamu Takai Chairperson of ICTF-15 EcoTopia Science Institute, and Department of Materials, Physics and Energy Engineering Graduate School of Engineering Nagoya University Japan

In order to analyze effect of the dicing process on the GaN epitaxial layer, the GaN-wafer is cut in sizes of the 0.7 mm square and the 1.7 mm square. The crystal characteristics of the GaN-chips have been measured using X-ray measurements and Raman spectra measurements. The full-width half maximum (FWHM) values of the X-ray rocking curves of (0002), (10–13) and (10–12) of the 0.7 mm square GaN-chip become wider than that of before the dicing process. The E2 (high) peak of Raman spectra at the edge in the 0.7mm square GaN-chip is shifted to lower wave number. In consideration of crystallography, we infer from these results that both the crystal strains and the screw dislocations have been generated during the dicing process.

In order to investigate the magnetic properties of GaAs:Er,O, we performed X-band ESR measurement on three different Er-concentration samples in the temperature region from T = 4.6 K to 18 K. Three types of Er-related ESR signals were observed below 18 K. The temperature dependence of the signal intensities and the result of the line shape analyses suggest that the luminescent related Er centers have a singlet-like ground state: that is, the Er-related centers are not homogenously distributed in GaAs:Er,O, and Er3+ ions can be antiferromagnetically coupled via the super exchange interaction. Moreover, we have shown that the Er-concentration dependence of intensities of ESR absorption has a strong correlation with the Er-concentration dependence of the PL intensities of GaAs:Er,O

We investigated the optical properties of Eu-implanted GaN and related-alloy semiconductors by photoluminescence (PL) and time resolved PL measurements at room temperature (RT). After thermal annealing, the red emission was observed in each sample due to the intra-4f transitions in Eu3+ ions. The PL intensity increases with Al incorporation into GaN while it decreases with In incorporation into GaN, indicating that the emission efficiency depends on the host materials while the emission wavelength is independent of the host materials. Since the decay times of Eu emission of the samples are found to be similar by time resolved PL measurements, the origin of the Eu emission of each sample is supposed to be same. Therefore, the difference in the PL intensity is attributed to the difference in the energy transfer efficiency because of the ion implantation damage and/or bandgap energy of the host materials.

Growth of GaAs by MOVPE (Metal-Organic Vapor-Phase Epitaxy) at a much lower temperature than conventional conditions of 650°C required to produce highly resistive buffer layers and molecular-layer-level abrupt heterojunctions and doped-layer interfaces. It has been widely recognized that growth at 550~600°C causes poor morphological surfaces on the grown layers. This paper describes a fundamental improvement of the low-temperature growth of GaAs, resulting in smooth surfaces with very low impurity concentrations. Excellent GaAs layers can be grown at 500°C by increasing partial pressure of AsH3 during growth. The method has been applied to high quality epitaxial layers for electronic device production.

We have fabricated two types of 1.5 μm light-emitting devices based on Er,O-codoped GaAs (GaAs:Er,O) using organometallic vapor phase epitaxy (OMVPE). In a device exhibiting a room-temperature lasing at the GaAs band-edge, the threshold current density increased with Er concentration. The Er intensity rose up steeply and then decreased gradually in the spontaneous emission region. In the stimulated emission region, it remained almost constant, reflecting ultrafast energy transfer to Er ions. In a device exhibiting a room-temperature lasing from strained GaInAs quantum wells (QWs) embedded in GaAs:Er,O, on the other hands, the lasing wavelength was designed to tune to the energy separation between the second excited states 4I11/2 and the ground state 4I15/2 of Er3+ ions. The Er intensity revealed initially steep increase with injected current density in the region for spontaneous emission from the GaInAs QWs. In the stimulated QW emission region, however, the intensity continued to increase with the current density.

Band structure of β-FeSi2 epitaxial and polycrystalline films was investigated by photoreflectance (PR) measurements. In the PR spectra, two critical points were obtained at Eg = 0.918 eV and Ei = 0.895 eV in the films. The Eg consistent with the direct transition energy at Y point in the Brillouin zone of β-FeSi2. The Ei was assigned as a transition-energy between conduction band and the acceptor-level originating from Si vacancies in β-FeSi2. The energy from top of valence band to the acceptor-level was determined to be 23 meV.

We investigated the relationship between optical properties and crystal quality of Eu-implanted GaN-based semiconductors. Emission peaks that are due to intra-4f shell transitions in Eu3+ ions were observed in Eu-implanted GaN, InGaN, and AlGaN. Emission wavelengths from the Eu ions were constant regardless of the matrix materials. The emission peak intensity in the Eu-implanted AlGaN was higher than that in the Eu-implanted InGaN or GaN because of less matrix damage by ion implantation.

Er-doped ZnO (ZnO:Er) thin films were grown by metalorganic chemical vapor deposition. Subsequent annealing improved the crystallinity of the ZnO:Er by suppressing nonradiative centers in the films. The annealed ZnO:Er showed clear 1.54 μm PL originating from the 4I13/2 → 4I15/2 transitions of Er3+ ions. This was in addition to luminescence from the ZnO host. Er-related PL intensity increased when prepared with annealing temperatures of 800–900 °C, while annealing at 1000 °C reduced the intensity. PL of 1.54 μm with high intensity was obtained in the ZnO:Er film that exhibited band-edge emission of free- or bound-excitons.