title: A Unique Approach to Generate Self-Aligned SiO2/Ge/SiO2/SiGe Gate-Stacking Heterostructures in a Single Fabrication Step.
abstract: We report a first-of-its-kind, unique approach for generating a self-aligned, gate-stacking heterostructure of Ge quantum dot (QD)/SiO2/SiGe shell on Si in a single fabrication step. The 4-nm-thick SiO2 layer between the Ge QD and SiGe shell fabricated during the single-step process is the result of an exquisitely controlled dynamic balance between the fluxes of oxygen and silicon interstitials. The high-quality interface properties of our "designer" heterostructure are evidenced by the low interface trap density of as low as 2-4 × 10(11) cm(-2) eV(-1) and superior transfer characteristics measured for Ge-based metal-oxide-semiconductor field-effect transistors (MOSFETs). Thanks to the very thin interfacial SiO2 layer, carrier storage within the Ge QDs with good memory endurance was established under relatively low-voltage programming/erasing conditions. We hope that our unique self-aligned, gate-stacking heterostructure provides an effective approach for the production of next-generation, high-performance Ge gate/SiO2/SiGe channel MOSFETs.
authors.affiliation: Department of Electronics Engineering, National ChiaoTung University, HsinChu, 300 Taiwan.
authors.forename: Wei-Ting
authors.initials: WT
authors.lastname: Lai
authors.affiliation: Department of Electrical Engineering, National Central University, ChungLi, 320 Taiwan.
authors.forename: Kuo-Ching
authors.initials: KC
authors.lastname: Yang
authors.affiliation: Department of Electrical Engineering, National Central University, ChungLi, 320 Taiwan.
authors.forename: Ting-Chia
authors.initials: TC
authors.lastname: Hsu
authors.affiliation: Department of Electrical Engineering, National Central University, ChungLi, 320 Taiwan.
authors.forename: Po-Hsiang
authors.initials: PH
authors.lastname: Liao
authors.affiliation: Department of Electrical Engineering, National Central University, ChungLi, 320 Taiwan.
authors.forename: Thomas
authors.initials: T
authors.lastname: George
authors.affiliation: Department of Electronics Engineering, National ChiaoTung University, HsinChu, 300 Taiwan.
authors.forename: Pei-Wen
authors.initials: PW
authors.lastname: Li
keywords: Gate-stacking heterostructure; Ge quantum dot; Self-aligned; SiGe channel