Nitride-stressor and quantum-size engineering in ge quantum-dot photoluminescence wavelength and exciton lifetime

Yu Hong Kuo, Shih Hsuan Chiu, Che Wei Tien, Sheng Di Lin, Wen Hao Chang, Thomas George, Horng Chih Lin, Pei Wen Li*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

We report local nitride-stressor engineering in combination with quantum-size tunability in Ge quantum dots (QDs) for tailoring photoluminescence (PL) wavelength and exciton lifetime. Spherical-shaped Ge QDs with tunable diameters ranging from 25–90 nm embedded within layers of thermally-grown SiO2 and chemical-vapor-deposited Si3N4 were fabricated by thermal oxidation of lithographically-patterned poly-Si0.85Ge0.15 pillars on top of buffer layers of SiO2 and Si3N4, respectively, in a self-organization approach. The effects of local stressors and quantum confinement on the strain and optical properties of Ge QDs were systematically investigated using Raman and PL measurements. We observed that when Ge QD diameter gets smaller than 60 nm, quantum confinement sets in and has a predominant influence on PL wavelength and exciton lifetime. Our self-organized Ge QD/Si3 N4 system provides a generic building block for the fabrication of active photonic devices on Si3N4 platform.

Original languageEnglish
Article number015001
Pages (from-to)1-9
Number of pages9
JournalNano Futures
Volume4
Issue number1
DOIs
StatePublished - 23 Mar 2020

Keywords

  • Germanium
  • Quantum confinement
  • Quantum dot
  • Si N
  • Strain

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