Size Tunable Strain And Interfacial Engineering Of Germanium Quantum Dots
2014 IEEE SILICON NANOELECTRONICS WORKSHOP (SNW)(2014)
Abstract
Spherical Ge quantum dots (QDs) of desire sizes and locations within the Si-containing layers has been demonstrated using thermal oxidation of SiGe nanopillars over buffer Si3N4 on the Si substrate. Local environment material of SiO2 imposes large stress onto the Ge QD, and the compressive strain progressively increases from 0.5 to 4% with a decrease in the QD size from 110 to 60nm. Such a high pressure of 1-4.5 GPa makes a striking transition in the crystalline structure from indirect bandgap diamond to direct bandgap tetragonal for Ge as evidenced by a significant blue shift in the LO phonon Raman lines and diffraction patterns (DPs), when decreasing the QD size. Remarkably, an opposite, red shift of the Raman lines is observed from the Ge QDs when removing the encapsulated layer of SiO2 from the QDs, indicating the QD experiencing a size-dependent tensile strain. This indicates that strain engineering on the Ge QDs is tunable by the QD size and their interactions with local environments.
MoreTranslated text
Key words
size tunable strain,interfacial engineering,spherical germanium quantum dot,silicon-containing layer,thermal oxidation,nanopillar,buffer,silicon substrate,compressive strain,crystalline structure,indirect bandgap diamond,direct bandgap tetragonal,blue shift,LO phonon Raman line,diffraction pattern,red shift,encapsulated layer,tensile strain,strain engineering,size 110 nm to 60 nm,pressure 1 GPa to 4.5 GPa,SiGe,Si3N4,SiO2,Ge
AI Read Science
Must-Reading Tree
Example
![](https://originalfileserver.aminer.cn/sys/aminer/pubs/mrt_preview.jpeg)
Generate MRT to find the research sequence of this paper
Chat Paper
Summary is being generated by the instructions you defined