| People | Locations | Statistics |
|---|---|---|
| Naji, M. |
| |
| Motta, Antonella |
| |
| Aletan, Dirar |
| |
| Mohamed, Tarek |
| |
| Ertürk, Emre |
| |
| Taccardi, Nicola |
| |
| Kononenko, Denys |
| |
| Petrov, R. H. | Madrid |
|
| Alshaaer, Mazen | Brussels |
|
| Bih, L. |
| |
| Casati, R. |
| |
| Muller, Hermance |
| |
| Kočí, Jan | Prague |
|
| Šuljagić, Marija |
| |
| Kalteremidou, Kalliopi-Artemi | Brussels |
|
| Azam, Siraj |
| |
| Ospanova, Alyiya |
| |
| Blanpain, Bart |
| |
| Ali, M. A. |
| |
| Popa, V. |
| |
| Rančić, M. |
| |
| Ollier, Nadège |
| |
| Azevedo, Nuno Monteiro |
| |
| Landes, Michael |
| |
| Rignanese, Gian-Marco |
|
Aktaş, Ozan
University of Cambridge
in Cooperation with on an Cooperation-Score of 37%
Topics
Publications (8/8 displayed)
- 2020Laser-driven phase segregation and tailoring of compositionally graded microstructures in Si-Ge nanoscale thin filmscitations
- 2020Laser processed semiconductors for integrated photonic devices
- 2020Laser-written silicon-germanium alloy microstructures with tunable compositionally graded profiles
- 2019Laser processing of amorphous semiconductors on planar substrates for photonic and optoelectronic applications
- 2018Wavelength conversion and supercontinuum generation in silicon optical fiberscitations
- 2017Tapered nanoscale chalcogenide fibers directly drawn from bulk glasses as optical couplers for high-index resonatorscitations
- 2017Chalcogenide microresonators tailored to distinct morphologies by the shaping of glasses on silica taperscitations
- 2017Tapered silicon core fibers with nano-spikes for optical coupling via spliced silica fiberscitations
Places of action
| Organizations | Location | People |
|---|
article
Laser-driven phase segregation and tailoring of compositionally graded microstructures in Si-Ge nanoscale thin films
Abstract
The ability to manipulate the composition of semiconductor alloys on demand and at nanometer-scale resolutions is a powerful tool that could be exploited to tune key properties such as the electronic band gap, mobility, and refractive index. However, existing methods to modify the composition involve altering the stoichiometry by temporal or spatial modulation of the process parameters during material growth, limiting the scalability and flexibility for device fabrication. Here, we report a laser processing method for localized tailoring of the composition in amorphous silicon-germanium (a-SiGe) nanoscale thin films on silicon substrates, postdeposition, by controlling phase segregation through the scan speed of the laser-induced molten zone. Laser-driven phase segregation at speeds adjustable from 0.1 to 100 mm s -1 allows access to previously unexplored solidification dynamics. The steady-state spatial distribution of the alloy constituents can be tuned directly by setting the laser scan speed constant to achieve indefinitely long Si 1-x Ge x microstructures, exhibiting the full range of compositions (0 < x < 1). To illustrate the potential, we demonstrate a photodetection application by exploiting the laser-written polycrystalline SiGe microstripes, showing tunability of the optical absorption edge over a wavelength range of 200 nm. Our method can be applied to pseudobinary alloys of ternary semiconductors, metals, ceramics, and organic crystals, which have phase diagrams similar to those of SiGe alloys. This study opens a route for direct laser writing of novel devices made of alloy microstructures with tunable composition profiles, including graded-index waveguides and metasurfaces, multispectral photodetectors, full-spectrum solar cells, and lateral heterostructures.