Strain Engineering of Germanium Nanobeams by Electrostatic Actuation

Ayan, Arman
Turkay, Deniz
Unlu, Buse
Naghinazhadahmadi, Parisa
Oliaei, Samad Nadimi Bavil
Boztug, Cicek
Yerci, Selçuk
Germanium (Ge) is a promising material for the development of a light source compatible with the silicon microfabrication technology, even though it is an indirect-bandgap material in its bulk form. Among various techniques suggested to boost the light emission efficiency of Ge, the strain induction is capable of providing the wavelength tunability if the strain is applied via an external force. Here, we introduce a method to control the amount of the axial strain, and therefore the emission wavelength, on a suspended Ge nanobeam by an applied voltage. We demonstrate, based on mechanical and electrical simulations, that axial strains over 4% can be achieved without experiencing any mechanical and/or electrical failure. We also show that the non-uniform strain distribution on the Ge nanobeam as a result of the applied voltage enhances light emission over 6 folds as compared to a Ge nanobeam with a uniform strain distribution. We anticipate that electrostatic actuation of Ge nanobeams provides a suitable platform for the realization of the on-chip tunable-wavelength infrared light sources that can be monolithically integrated on Si chips.


Strain induction on GE nanobeams by electrostatic actuation
Ayan, Arman; Yerci, Selçuk; Department of Electrical and Electronics Engineering (2018)
Germanium (Ge) is one of the most promising materials to accomplish the monolithic integration of optics and electronics on the same chip, mainly due to its compatibility with the existing silicon (Si) technology, high charge carrier mobility and high absorption coefficient in the near-infrared region. However, realization of efficient Ge light emitters requires techniques such as tensile strain induction, tin (Sn) incorporation and/or heavy n-type doping to alter its band gap enabling direct transitions. A...
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Coaxial electrospinning of poly(ethylene glycol) (PEG)/polyamide 6 (PA6) was successfully used in development of nanofibrous thermal energy storage (TES) material. Halloysite nanotubes (HNTs) were introduced into the core/shell structured TES materials at various concentrations (0.5, 1, 3 and 5 wt. %). Surface activation of HNT was also conducted by piranha etching in order to increase the affinity between piranha-etched nanotubes (HNT-P) and PEG. The core/shell structured materials were characterized using...
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Germanium nanocrystals (Ge NCs) embedded in single and multilayer silicon oxide and silicon nitride matrices have been synthesized using plasma enhanced chemical vapor deposition followed by conventional furnace annealing or rapid thermal processing in N-2 ambient. Compositions of the films were determined by Rutherford backscattering spectrometry and x-ray photoelectron spectroscopy. The formation of NCs under suitable process conditions was observed with high resolution transmission electron microscope mi...
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Gate-tunable high-mobility electrons on atomically thin graphene layers provide a unique opportunity to control electromagnetic waves in a very broad spectrum. In this paper, we describe an electrically-controlled multipixel terahertz light modulators. The spatial light modulator is fabricated using two large-area graphene layers grown by chemical vapor deposition and transferred on THz transparent and flexible substrates. Room temperature ionic liquid, inserted between the graphene, provides mutual gating ...
Citation Formats
A. Ayan et al., “Strain Engineering of Germanium Nanobeams by Electrostatic Actuation,” SCIENTIFIC REPORTS, pp. 0–0, 2019, Accessed: 00, 2020. [Online]. Available: