Investigation of free electron system at ferroelectric domain boundaries coupled with spontaneous polarization

我们从实验上研究了本征表面电子层的存在[1，2]。此外，我们的结果成为整个项目的领导者，Okuyama教授的团队提出的新的铁电场效应装置[3]的基础。然而，到目前为止，人们对本征表面电子层的怀疑仍然很多。在这些怀疑的启发下，我们一直在进行各种实验，以研究所有可能招致批评的问题。由于石桥教授的慷慨，我们使用了新建成的超高压系统和用不同方法生长的晶体以及纳米级的表征来做到这一点。作为副产品，我们首次发现了n型和p型非易失性表面载流子层都是电可控的。在我们的报告中，我们报告了这些进展和对表面载流子层的理解现状。此外，同样的铁电场效应通常被认为是使用铁电材料的电阻随机存取存储器(RRAM)的起源。[1]Y.Watanabe等人，Phys.Rev.Lett.86,332(2001).[2]物理评论焦点(2001年1月9日)http://focus.aps.org/v7/st1.html[3]G.Hirooka，M.Noda和M.Okuyama，Jpn.J.Appl.Phys.43,2190(2004)

We've investigagted experimentally the existence of the intrinsic surface electron layer [1,2]. Furthermore, our results became the basis of the new ferroelectric field effect device [3] proposed by Prof. Okuyama's group who was the leader of the entire project. However, much skepticism about the intrinsic surface electron layer remains so far. Inspired by these suspicions, we have been conducting various experiments to examine all the conceivable issues that may invite criticisms. Owing to Prof. Ishibashi's generosity, we have done this using a newly built UHV system and crystals grown by different methods as well as nano-meter scale characterizations. As a byproduct we have found both n-and p-type non-volatile surface carrier layer that are electrically controllable for the first time. In our presentation, we report these progresses and the status of the understanding of surface carrier layer. Additionally, the same ferroelectric field effect is often thought to be the origin of the resistance-RAM's (RRAM) that use ferroelectrics.[1]Y.Watanabe et al.,Phys.Rev.Lett.86,332 (2001).[2]Physical Review Focus (Jan.9,2001) http://focus.aps.org/v7/st1.html[3]G.Hirooka, M.Noda and M.Okuyama, Jpn.J.Appl.Phys.43,2190 (2004)