[...]... frontier called ‘transparent oxide semiconductors (TOSs).’ Therefore, we now consider that TOSs have the potential to develop new functionalities useful for novel optoelectronic devices that are hard to realize by current Si-based semiconductor technology The discovery of the p-type TOSs resulted from rational considerations regarding to the design of new TOSs based on knowledge about electronic structures... Technology Its new mission was to impart higher education to professional engineers and develop their capabilities for research and development, in order to contribute to the modernization of Japanese industries xii Materials Research at the Tokyo Institute of Technology Materials research has been actively carried out throughout the entire history of the University Currently, the Tokyo Institute of Technology... been proven to be valid by the development of new TOSs including p-type TOSs These new TOSs led to transparent electronic devices such as UV LEDs and transparent thin film transistors (TFTs) In addition, we have proposed that the use of natural nanostructures embedded in crystal structures of TOSs is very effective in the cultivation of new functions in oxides 8 Nanomaterials: From Research to Applications... on an atomically flattened (100)-YSZ single-crystal substrate at 600◦ C (Fig 1.4) [17] We also fabricated single-crystalline ITO films having Fig 1.4 AFM image of superflat ITO thin films A step corresponding to a monolayer of ITO is clearly seen 12 Nanomaterials: From Research to Applications an atomically flat surface (Rrms ∼ 0.2 nm @ 1 × 1 cm2 ) on the (111) surface of YSZ at 900◦ C [18] This atomically... King Gustov (Courtesy of Professor Kenneth J Wynne) The Tokyo Institute of Technology was originally founded as the Tokyo Vocational School in May 1881 The School was renamed as the Tokyo Technical School in 1890 and later became the Tokyo Higher Technical School in 1901 In 1929, the Tokyo Technical School was promoted to the status of a degree-conferring university and was renamed as the Tokyo Institute... and research centers for materials science, not only in Japan but also by world standards, as shown in the following chapters In its history spanning more than a century, two Professors of the Tokyo Institute of Technology, Professor Yogoro Kato and Professor Hideki Shirakawa, stand out from the many excellent Professors of Materials Science Professor Yogoro Kato (1872–1967) was invited to join the Tokyo... laser, nano-porous materials Nanomaterials: From Research to Applications H Hosono, Y Mishima, H Takezoe and K.J.D MacKenzie © 2006 Elsevier Ltd All rights reserved 3 4 Nanomaterials: From Research to Applications 1.1 General Introduction 1.1.1 Research background The Clerk number shows the order in terms of natural abundance of the elements in the earth’s crust The top ten on the list are oxygen, silicon,... deviation of the chemical composition from stoichiometry, resulting in the decomposition of LnCuOCh into Ln2 O3 , Ln2 O2 Ch, and Cu2 Ch Although intensive efforts have been made to grow epitaxial LnCuOCh films at high temperatures by a PLD technique, the epitaxial films have not been obtained Therefore, we employed the R-SPE technique to 18 Nanomaterials: From Research to Applications Fig 1.10 Procedure... Further Mg doping increased the hole concentration up to 2 × 1020 cm−3 The Hall mobility of the Mg-doped films is also enhanced from 0.2 to 4.0 cm2 ·V−1 ·s−1 by anion substitution from S to Se, resulting in an increase in the electrical conductivity from 5.9 to 140 S·cm−1 (Fig 1.15) It is noteworthy that the mobility of the Mg-doped films is reduced to only half that of the undoped films despite the heavy... ground state, which may 10 Nanomaterials: From Research to Applications be regarded as a ‘quasi-closed shell’ configuration On the basis of the idea that such ions are expected to behave similarly to Cu+ ions with 3d10 closed shell configurations and to enhance the dispersion of the valence band, we have found that normal spinel ZnRh2 O4 is a p-type wide-gap semiconductor with a band gap of ∼ 2.1 eV [8] The . alt="" Nanomaterials: From Research to Applications This page intentionally left blank Nanomaterials: From Research to Applications H. Hosono, Y. Mishima, H. Takezoe, and K.J.D. MacKenzie Tokyo. reserved. This work is protected under copyright by Elsevier Ltd, and the following terms and conditions apply to its use: Photocopying Single photocopies of single chapters may be made for personal use. copyright laws. Permission of the Publisher and payment of a fee is required for all other photocopying, including multiple or systematic copying, copying for advertising or promotional purposes,