The data of the article“Study on Scattering Particles in Bi₁₂SiO₂₀ Crystals Grown by the Vertical Bridgman Method”

I. Experimental ObjectivesThis study systematically investigates the morphology, distribution, composition, and formation mechanism of 5 µm-scale scattering particles in BSO crystals grown by the vertical Bridgman method. Initial localization of scattering particles was performed using transmitted polarizing microscopy (TPM). Subsequent detailed analysis of morphological features, spatial distribution, and composition was conducted using ultra‑high‑resolution scanning electron microscopy (SEM). By correlating crystal growth kinetics with the growth environment and mechanical setup, the formation mechanism of these scattering particles was thoroughly examined. All experimental data were obtained through in‑situ observation and direct measurement, providing direct support for conclusions regarding the morphology, composition, distribution, and formation mechanism of scattering particles in BSO crystals.II. Testing ConditionsDefect morphology observation:An XPT‑7 transmitted polarizing microscope (TPM, magnification 100–400×) was used to locate and classify typical scattering particles. A Thermo Scientific Verios G4 UC ultra‑high‑resolution field‑emission scanning electron microscope (SEM, secondary electron/backscattered electron mode) was employed to observe the microscopic morphology of the particles. Micro‑area composition testing was performed using the energy‑dispersive X‑ray spectroscopy (EDS) system attached to the SEM.Composition analysis: A 30% nitric acid solution was used as the etchant. Samples were etched at room temperature for 2 h and 6 h, respectively. SEM was used to observe morphological changes and distribution patterns of the scattering particles before and after etching. Micro‑area composition analysis was conducted using the attached EDS system.Optical performance testing:A Shimadzu UV‑2501 PC ultraviolet‑visible spectrophotometer (wavelength range 300–700 nm, slit width 1 nm) was used to measure the transmittance spectra of different scattering regions in the crystal wafer.Orientation statistics: The XPT‑7 TPM (magnification 100–400×) was used to obtain the coordinates of the upper and lower surface endpoints of 23 scattering particles. The angles between the particles and the crystal [100] growth direction were calculated, and Gaussian fitting was performed using Origin software.III. Description of Test Data AcquisitionSample preparationFigure 1 shows a wafer sample (25 × 25 × 1.5 mm³) obtained by cutting and polishing perpendicular to the [001] growth direction of the BSO crystal. Scattering particles inside the wafer are visible under strong light, serving as the research subject of this paper.Optical transmittance datasetFigure 2 presents transmittance‑wavelength curves (300–700 nm) measured from six regions of the sample (Group A: three non‑scattering regions; Group B: three scattering regions). The data are provided in CSV format and can be used directly to reproduce the conclusion that “the curves of Group A overlap, while the transmittance of Group B decreases significantly in the 500–700 nm range.”Morphology and spatial distribution datasetFigure 3 records the coordinate information of 23 scattering particles on the A‑side and B‑side of the sample. The calculated angles relative to the [100] direction range from 0.03° to 0.94°, with the peak concentrated near 0.06°. The data are provided in Excel (.xlsx) format.Figure 4 is a schematic diagram of the scattering particle positions: Figure 4(a) illustrates their positions along the [100] direction, while Figure 4(b) shows their positions on the (100) crystal plane.Figure 5 compares the morphology of the same scattering particle observed on the A‑side and B‑side using TPM and SEM, respectively.Figure 6 and Figure 7 show SEM morphology images of the wafer after HNO₃ etching for 2 h and 6 h, respectively. The changes in particle morphology with etching time further confirm the gradual transition of scattering particles from a cylindrical shape to an H‑shaped three‑dimensional structure.Composition analysis datasetFigure 8 presents a set of EDS spectra: four test regions (corresponding to Spectrum 1, 3, 18, and 19 in Table 1). Spectrum 1 and 18 correspond to the scattering particles (high‑purity Pt), while Spectrum 3 and 19 correspond to the crystal matrix (containing Bi, Si, and O elements).Table 1 is a composition analysis data sheet, listing the atomic percentages of elements in each spectrum (e.g., Spectrum 1: Pt 85.39 at%, Bi 14.61 at%; Spectrum 3: Bi 48.12 at%, Si 3.09 at%, O 48.79 at%). The data are provided in .docx format.Auxiliary dataCrystal growth apparatus parameters: lead screw pitch 0.7 mm, driven gear number 120, single‑tooth feed 6 μm.Data processing methods: SEM images were calibrated using drawing software; EDS data were quantitatively analyzed using the instrument’s built‑in software; optical transmittance data were plotted using Origin; angle data were fitted using Gaussian fitting in Origin to ensure data accuracy.