Large electron concentration modulation using capacitance enhancement in SrTiO3/SmTiO3 Fin-field effect transistors
Abstract
Solid-state modulation of 2-dimensional electron gases (2DEGs) with extreme (∼3.3 × 1014 cm−2) densities corresponding to 1/2 electron per interface unit cell at complex oxide heterointerfaces (such as SrTiO3/GdTiO3 or SrTiO3/SmTiO3) is challenging because it requires enormous gate capacitances. One way to achieve large gate capacitances is by geometrical capacitance enhancement in fin structures. In this work, we fabricate both Au-gated planar field effect transistors (FETs) and Fin-FETs with varying fin-widths on 60 nm SrTiO3/5 nm SmTiO3 thin films grown by hybrid molecular beam epitaxy. We find that the FinFETs exhibit higher gate capacitance compared to planar FETs. By scaling down the SrTiO3/SmTiO3 fin widths, we demonstrate further gate capacitance enhancement, almost twice compared to the planar FETs. In the FinFETs with narrowest fin-widths, we demonstrate a record 2DEG electron concentration modulation of ∼2.4 × 1014 cm−2.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 02, 2016
- Source ID
- 10.1063/1.4948770
Entities
People
- Amit Verma
- Debdeep Jena
- Kazuki Nomoto
- Santosh Raghavan
- Susanne Stemmer
- wan sik hwang
Organizations
- Cornell University
- Korea Aerospace University
- Office of Naval Research
- University of California
- University of Notre Dame