DOI: 10.5281/zenodo.15082447
title: Dataset for "Highly strained Ge nanostructures and direct bandgap transition induced by femtosecond laser"

description: Dataset for Highly strained Ge nanostructures and direct bandgap transition induced by femtosecond laser

To be published in Semiconductor Science and Technology, IOP publishing

 

The dataset is organized into folders corresponding to the figures in the manuscript (e.g., Figure 1, Figure 2, etc.). Each folder contains subfolders or files that are specific to the data presented in the respective figure. Below is an overview of the folder structure:



Figure 1/



SEM: This folder contains scanning electron microscopy (SEM) images corresponding to each parameter set, with varying zoom levels indicated in the file names (e.g., _5kx, _10kx, _25kx, _50kx). The images are saved in TIFF format with a resolution of 1024x768 pixels and were recorded using a Carl Zeiss AG - SUPRA 40 SEM. Additionally, critical acquisition details such as the scale bar, accelerating voltage (EHT), and the date and time of capture are embedded in the images, providing full context for their generation. Each image is also named according to the specific parameter used (a separate table lists these parameters below).










File name



Laser fluence (J/cm²)



Scan speed (mm/s)





0.5V_*kx.tif



0.10



10





1.5V_*kx.tif



0.29



10





2.5V_*kx.tif



0.48



10





50mmps_*kx.tif



0.29



50





2000mmps_*kx.tif



0.29



2000






 





Raman_50x: This folder contains photos and Raman spectroscopy results acquired using a 50x objective lens, related to Figure 1(a-e). The *.jpg files include microscope images, with file names indicating the corresponding subfigures (1a, 1b, etc.). Colored crosses on the images mark the locations where Raman signals were acquired. The Raw.csv file contains the raw Raman dataset, with the first column representing the wavenumber in cm⁻¹. The second column indicates background noise (arbitrary unit), which should be subtracted from the actual intensity. The remaining columns represent the Raman intensity (arbitrary unit) for samples, categorized as follows: Figure 1a (S23, S24, S25, S26, S27); Figure 1b: Samples (S19, S20, S21, S22); Figure 1c: Samples (S10, S12, S13, S14); Figure 1d: Samples (S15, S16, S17, S18); Figure 1e: Samples (S6, S7, S8, S9). The color code of the crosses on the images follows the order: Red, Blue, Green, Cyan, and Magenta, corresponding to the sample header order as listed above.

Raman_100x: This folder contains photos and Raman spectroscopy results acquired using a 100x objective lens, related to Figure 1(f-h). The *.tif files include microscope images, with cross markings indicating the locations where line scans are performed. The Raw.csv file contains the corresponding Raman spectra. The line scan at the left of the figure uses spectra from Single_Secptrum_007 and Single_Secptrum_024, and the scan at the right uses Single_Secptrum_007 to Single_Secptrum_047. The depth of focus (Z) for each acquisition is also included in the header (unit µm). Figure 1(h) uses spectra 035, 037 and 039.


Figure 2/



FIB: This folder contains a series of images captured using the JEOL JIB-4700F focused ion beam (FIB) system during the sample preparation process. Selected images from this dataset are presented in Figure 2a and Figure 2b of the manuscript.

EDS: This folder contains TEM images and EDX (energy-dispersive X-ray) data collected using the JEOL JEM-2200FS system. The following files are included:



b2 DF 400k eds.dm3: Dark field (DF) TEM image of the area subjected to EDS analysis, taken at 400k magnification. The *.dm3 file can be analyzed using software such as DigitalMicrograph (Gatan Microscopy Suite), imageJ, crysTBox or similar programs.

b2 eds1.emsa, b2 eds2.emsa, b2 eds3.emsa: Raw EDS data from three different locations on the sample. These *.emsa files can be analyzed using, e.g., NIST DTSA-II Oberon, Oxford INCA, Thermo Fisher Pathfinder, or similar programs.

b2 eds1.jpg, b2 eds2.jpg, b2 eds3.jpg: These *.jpg files display the EDS spectra with identified elements as exported from the TEM system.



Figure 3/



Lo: This folder contains low-resolution TEM images along with selected area electron diffraction (SAED) patterns. The following files are included: d1 TEM 30k.dm3, f1 TEM 25k.dm3, h2 TEM 25k.dm3: TEM images captured at magnifications of 30k and 25k; d1 diff.dm3, f1 diff rings.dm3, h1 diff.dm3: Corresponding SAED patterns for each TEM image (These files represent diffraction data collected at the same locations as the TEM images). Image set f1 is presented in Figure 3(a) as an example for illustration.

Hi: This folder contains high-resolution TEM (HRTEM) images and SAED patterns related to Figure 3. The following files are included: w0 150k.dm3: TEM image at 150k magnification, showing the location of interest for both the SAED and HRTEM analysis (Figure 3b in the manuscript); w0 diff.dm3: SAED pattern (scale bar is mislabelled as 10 nm while the correct one should be 5 1/nm) corresponding to the image in w0 150k.dm3, shown in Figure 3c; w1-w5.dm3: A series of various HRTEM images taken from the location of interest, related to Figure 3d. The respective analysis in the manuscript was taken using CrysTBox (diffractGUI, cellViewer and ringGUI).


Figure 4/



The file r1 600k.dm3 contains a high-resolution TEM (HRTEM) image captured at 600k magnification, which is included in Figure 4 of the manuscript. The respective analysis presented in the manuscript was performed using DigitalMicrograph, CrysTBox (including diffractGUI and cellViewer), and the OrientationJ plugin in ImageJ.


Figure 5/



This folder contains the X-ray diffraction (XRD) spectra shown in Figure 5a and 5b of the manuscript. The files are in *.ras format containing measurement conditions and actual spectra, which can be opened directly in e.g. notepad. These spectra are used to interpret the crystallographic information presented in the manuscript. In addition, Peakfit.pdf contains the peak fitting for Figure 5(c).


Figure 6/



The file RTA.csv contains total reflectance (%R) and transmittance (%T) spectra, measured using a UV-Vis-NIR spectrophotometer (Agilent Cary 5000), along with the calculated absorbance (%A). Note that transmittance values at wavelengths lower than 1500 nm are assumed to be zero, as the light is completely absorbed by the substrate in this range.



 
description: The authors acknowledge the provision of facilities and technical support by Aalto University at OtaNano-Micronova Nanofabrication Centre and Nanomicroscopy Center (NMC).