Raman Spectroscopy Study on the Surface of High Temperature and High Pressure Diamond Crystal in Geology, Rock and Minerals
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2022-11-10 |
| Journal | Highlights in Science Engineering and Technology |
| Authors | Shi Li, Hui Chi, Wei Wang, Yong Yu |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Defect Engineering in Diamond Crystals
Section titled âTechnical Documentation & Analysis: Defect Engineering in Diamond CrystalsâThis document analyzes the research paper âRaman Spectroscopy Study on the Surface of High Temperature and High Pressure Diamond Crystal in Geology, Rock and Mineralsâ to highlight the critical role of material purity, defect control, and advanced characterization in diamond science. 6CCVD specializes in providing the high-quality, customized MPCVD diamond materials necessary to advance research in defect physics, quantum sensing, and high-power optics.
Executive Summary
Section titled âExecutive Summaryâ- Research Focus: Comprehensive spectroscopic analysis (IR, PL, Raman, 3D Fluorescence) of HPHT synthetic diamonds subjected to high-temperature and high-pressure (HPHT) treatment (1500-1700°C, 5-6 GPa) to understand color origin and defect transformation.
- Defect Identification: Infrared spectroscopy confirmed the presence of sp3-CH2 and sp2-CH2 hydrocarbon defects, which are characteristic of HPHT synthetic growth.
- Defect Transformation: PL analysis demonstrated that the HPHT treatment significantly reduced the concentration of NV- centers (peak weakened at 637 nm) while simultaneously enhancing the concentration of SiV- centers (peak significantly enhanced at 737 nm).
- Material Quality Requirement: The study underscores the necessity of precise defect control (N, Si, C-H impurities) for tailoring the optical and electronic properties of synthetic diamond materials.
- 6CCVD Value Proposition: 6CCVD provides high-purity MPCVD diamond substrates (SCD and PCD) with inherently low native nitrogen content, enabling superior control over intentional defect incorporation (e.g., SiV, NV) for quantum and optical applications, surpassing the limitations of typical HPHT material.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the experimental section, detailing the material processing and characterization conditions:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Sample Dimensions | 3 x 3 x 1 | mm | HPHT Synthetic Diamond (Rough) |
| Processing Pressure | 5 - 6 | GPa | Color-fading treatment |
| Processing Temperature | 1500 - 1700 | °C | Color-fading treatment range |
| Heating Time | 200 | s | HPHT treatment cycle |
| Cooling Time | 400 | s | HPHT treatment cycle |
| X-ray Voltage | 20 | kV | Elemental composition analysis (QUANTâX) |
| IR Scanning Range | 650 - 6000 | cm-1 | Fourier Transform Infrared Microscopy |
| IR Resolution | 4 | cm-1 | Fourier Transform Infrared Microscopy |
| PL Excitation Wavelengths | 532, 633 | nm | Defect analysis (NV, SiV centers) |
| Raman Laser Wavelengths | 473, 532, 785 | nm | Spectroscopy testing |
| SiV- Center PL Peak | 737 | nm | Significantly enhanced after treatment |
| NV- Center PL Peak | 637 | nm | Weakened after treatment |
Key Methodologies
Section titled âKey MethodologiesâThe research employed a multi-modal spectroscopic approach to characterize the structural and chemical changes in the diamond samples:
- Sample Selection and Preparation: Five yellow HPHT synthetic rough diamonds (cube/octahedron shape) were selected, all synthesized under the same conditions.
- High-Temperature/High-Pressure Treatment: Samples were subjected to HPHT processing (1500-1700°C, 5-6 GPa) to remove the yellow tint and improve transparency.
- Surface and Internal Observation:
- Ultra-depth-of-field microscopy for surface topography.
- Gemmological microscopy for internal features.
- Diamond Observer (UV <220 nm source) for fluorescence and phosphorescence analysis.
- Elemental and Structural Analysis:
- X-ray Spectrometry (Thermo Scientific QUANTâX) for elemental composition of inclusions.
- X-ray Rocking Curve analysis (mentioned in Abstract) for lattice quality.
- Infrared Spectroscopy (IR): Used to quantify boron and nitrogen content, and to identify hydrocarbon defects (sp3-CH2 and sp2-CH2) via absorption peaks (e.g., 2850 cm-1, 2920 cm-1).
- Photoluminescence (PL) Spectroscopy: Used to analyze impurity elements and defect types (e.g., NV- centers, SiV- centers) using 532 nm and 633 nm excitation lasers.
- Laser Raman Spectroscopy: Used for general material testing and normalization of PL spectra.
- 3D Fluorescence Spectroscopy: Used to map fluorescence intensity changes across varying excitation and emission wavelengths, providing a comprehensive view of defect changes.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe research demonstrates the critical need for materials with controlled defect profiles for advanced applications. 6CCVDâs MPCVD technology offers superior control over impurity incorporation compared to the HPHT material studied.
Applicable Materials for Defect Engineering Research
Section titled âApplicable Materials for Defect Engineering ResearchâTo replicate or extend this research, particularly focusing on quantum defects (NV, SiV) and minimizing unwanted impurities (like C-H groups), 6CCVD recommends the following materials:
| 6CCVD Material | Key Feature | Relevance to Research |
|---|---|---|
| High-Purity SCD | Ultra-low native nitrogen (< 1 ppb) | Ideal starting material for precise, intentional creation of specific color centers (e.g., NV, SiV) without interference from background impurities. |
| Optical Grade SCD | Polished to Ra < 1 nm | Essential for high-resolution confocal microscopy and spectroscopy (Raman/PL) to minimize surface scattering artifacts and ensure accurate defect measurement. |
| Silicon-Doped SCD | Intentional Si incorporation | Directly supports research into SiV- centers (737 nm peak), allowing scientists to tune Si concentration for optimized quantum emitter performance. |
| PCD Plates (Inch-Size) | Large area, high thermal conductivity | Suitable for scaling up high-power optical components or thermal management studies where defect control is still required. |
Customization Potential for Advanced Studies
Section titled âCustomization Potential for Advanced StudiesâThe paper utilized small, rough samples. 6CCVD enables researchers to transition from small-scale analysis to device integration:
- Custom Dimensions: We provide SCD and PCD plates/wafers up to 125 mm in diameter, significantly larger than the 3 mm samples used in this study, facilitating device fabrication.
- Precision Polishing: Our capability to achieve surface roughness of Ra < 1 nm (SCD) and Ra < 5 nm (Inch-size PCD) ensures optimal optical performance for high-sensitivity PL and Raman measurements.
- Integrated Metalization: While the paper focused on bulk analysis, 6CCVD offers in-house metalization services (Au, Pt, Pd, Ti, W, Cu) for creating electrical contacts or optical coatings directly onto the diamond surface, crucial for integrating defect centers into functional devices.
Engineering Support
Section titled âEngineering SupportâThe research highlights the complex relationship between high-temperature processing and defect mobility (e.g., transformation of NV- to SiV- centers).
- Defect Control Expertise: 6CCVDâs in-house PhD engineering team specializes in tailoring MPCVD growth recipes (gas mixtures, pressure, temperature) to achieve specific lattice quality and targeted defect concentrations, crucial for similar quantum sensing and optical component projects.
- Global Logistics: We ensure reliable, global shipping (DDU default, DDP available) of sensitive materials, supporting international research collaborations.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
This paper analyses the colour origin and colour change mechanism of high temperature and high-pressure synthetic diamonds through experiments. In this paper, ultraviolet-visible absorption spectroscopy, infrared spectroscopy, photoluminescence spectroscopy, three-dimensional fluorescence spectroscopy, laser Raman spectroscopy and X-ray rocking curve were used for analysis. The results show that it is easy to identify genuine and fake gemstones based on Raman testing of the gemstone itself. The measurement of tiny inclusions with a confocal microscope system can provide information on whether the gemstone is natural or artificially improved, and even trace the origin of the gemstone. Width at half maximum of the Raman spectrum. Phonon âlifetimeâ can provide information on whether the gemstone is natural or synthetic. The photoluminescence spectrum of gemstones can also provide valuable information about the sample. This article can also identify natural gemstones or synthetic gemstones accordingly.