Functionality in Insulating Oxide Thin Films: Work Function Control and Polar Surface



The role of insulating layer is critical in electronic devices and hence preparing a reliable insulating substrate and insulating thin films is a starting point to fabricate any types of devices: Electron distribution engineering is entirely thanks to “insulating” character of insulators. In this chapter, we show that various properties other than the insulating character can be tuned in insulating oxide thin films, giving a significant controllability in designing surface and interface properties. In the first part of this chapter we show that the work function of oxide heterostructures is largely modulated using various aspects of insulating thin films. One of the properties characteristic of insulating films is “polarity,” which has increasingly been attracting attention. In the last part of this chapter we address growth and characterization of MgO(111) film, which is a representative polar oxide system.


Work function Polar surface Polar oxide films Thin film growth Metal–insulator interface 



The author thanks Hideo Hosono, Kosuke Matsuzaki, Asahi Makishima, Nobuhiro Shigaki, Sho Kumada, Hironori Takagi, Takayoshi Katase, Masashi Miyakawa for fruitful collaboration. Financial support from MEXT (Elements Science and Technology Project and Elements Strategy Initiative to Form Core Research Center) and JSPS (KAKENHI Grant No. 25286056) are greatly acknowledged.


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© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Secure Materials Center, Materials and Structures LaboratoryTokyo Institute of TechnologyYokohamaJapan
  2. 2.Mitsubishi Chemical Group Science and Technology Research CenterYokohamaJapan

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