Creation of exotic low-dimensional material originated from phyllosilicate and control of its electronic property

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K18893
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 29:Applied condensed matter physics and related fields
• Research Institution: Nagoya University
• Principal Investigator: Nakatsuka Osamu 名古屋大学, 工学研究科, 教授 (20334998)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: 低次元物質 / 珪酸塩鉱物 / 結晶材料 / 半導体 / エレクトロニクス / 物質科学 / 薄膜 / 表面・界面

Outline of Final Research Achievements

In this study, we focused on chemically stable phyllosilicates such as mica, aiming to clarify and control their crystalline and electronic properties, as well as to create two-dimensional materials by transferring them from molecular layers thinning onto substrates. We developed the transfer technique on some substrates using direct bonding between mica and substrates with a peeling method with Scotch tape. It was found that hydrophobic surfaces treated with dilute HF acid cleaning is suitable for the transfer. XRD measurements before and after the transfer revealed multiple-oriented crystals with different spacing lattice planes in the bulk mica before transfer, although a diffraction peak corresponding to a single plane spacing was observed after the transfer. In addition, we also investigated Ge thin film transfer and smoothing techniques for group-IV materials to develop the transfer process.

Free Research Field

半導体工学

Academic Significance and Societal Importance of the Research Achievements

本研究では、珪酸塩鉱物に注目し、その層状物質である雲母を基材とした低次元材料創製に挑戦した。珪酸塩鉱物は化学的に強固なSiO4四面体構造を基本構造に持ち、多様な結晶構造を取る。雲母は、SiO4四面体から成る2次元的平面上構造内部に、いくつかの金属元素を含み、分子層状に容易に剥離可能なことから、低次元材料への加工容易性が期待できる。雲母は優れた絶縁体であり、絶縁体基板としても用いられる一方、その材料自身の結晶構造、電子物性や電気的特性に関する報告は乏しい。層状珪酸塩物質内の金属元素類を制御できれば、そのエネルギーバンド構造や電子物性を自在操作し、新世代電子デバイスに応用できる可能性が期待できる。