Department of Chemical Engineering and Materials Science, University of Minnesota, Twin Cities, Minneapolis, MN 55455.
School of Physics and Astronomy, University of Minnesota, Twin Cities, Minneapolis, MN 55455.
Proc Natl Acad Sci U S A. 2022 Jun 7;119(23):e2202189119. doi: 10.1073/pnas.2202189119. Epub 2022 Jun 2.
SignificanceSemiconductor interfaces are among the most important in use in modern technology. The properties they exhibit can either enable or disable the characteristics of the materials they connect for functional performance. While much is known about important junctions involving conventional semiconductors such as Si and GaAs, there are several unsolved mysteries surrounding interfaces between oxide semiconductors. Here we resolve a long-standing issue concerning the measurement of anomalously low dielectric constants in SrTiO films with record high electron mobilities. We show that the junction between doped and undoped SrTiO required to make dielectric constant measurements masks the dielectric properties of the undoped film. Through modeling, we extract the latter and show that it is much higher than previously measured.
意义半导体界面在现代技术中应用最为广泛。它们所表现出的性质，要么使它们所连接的材料的特性得以实现，要么使其特性无法实现。虽然人们对涉及传统半导体如 Si 和 GaAs 的重要结有了很多了解，但氧化物半导体之间的界面仍存在一些未解之谜。在这里，我们解决了一个长期以来关于 SrTiO 薄膜中反常低介电常数测量的问题，这些 SrTiO 薄膜具有创纪录的高电子迁移率。我们表明，进行介电常数测量所需的掺杂和未掺杂 SrTiO 之间的结掩盖了未掺杂薄膜的介电性质。通过建模，我们提取了后者，并表明它比以前测量的要高得多。
