Investigation of mechanism of electrical conduction via functionalized dislocation networks in atomically-bonded metal-oxide crystals

2014 Fiscal Year Final Research Report

• Project/Area Number: 24360017
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Thin film/Surface and interfacial physical properties
• Research Institution: Osaka University
• Principal Investigator: SAKAI Akira 大阪大学, 基礎工学研究科, 教授 (20314031)
• Co-Investigator(Renkei-kenkyūsha): NAKAMURA Yoshiaki 大阪大学, 大学院基礎工学研究科, 教授 (60345105) ; KIKKAWA Jun 物質材料研究機構, 先端的共通技術部門表界面構造物性ユニット, 主任研究員 (20435754)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 転位 / 抵抗スイッチング / 金属酸化物結晶 / 電気伝導 / ヒステリシス / 空間電荷制限電流 / 酸素空孔 / 欠陥準位

Outline of Final Research Achievements

We have controlled dislocation structure and morphology in SrTiO3 crystals by using the atomic bonding method (ABM) and investigated electrical conduction mechanisms via dislocation networks in the crystals formed by ABM. Although resistive switching phenomena have been observed for both Nb-doped SrTiO3 and reduction-annealed non-doped SrTiO3 (RSTO), their mechanisms are different from each other: the former can be explained by carrier emission and capture at metal/SrTiO3 interfacial traps accompanied by the space charge limited current conduction, and the latter by the drift motion of oxygen vacancies in the crystal. In particular, by measuring electrical properties of micrometer-scaled devices made from the atomically bonded RSTO, it was found that the dislocation network can effectively be functionalized as an electrical conduction site having the ability of resistive switching.

Free Research Field

材料物性工学