Nanodiamonds for device applications - An investigation of the properties of boron-doped detonation nanodiamonds
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2018-02-13 |
| Journal | Scientific Reports |
| Authors | Abdulkareem Afandi, Ashley Howkins, Ian W. Boyd, Richard B. Jackman |
| Institutions | London Centre for Nanotechnology, Brunel University of London |
| Citations | 47 |
| Analysis | Full AI Review Included |
Technical Analysis & Product Strategy: Boron-Doped Detonation Nanodiamonds (B-DNDs)
Section titled âTechnical Analysis & Product Strategy: Boron-Doped Detonation Nanodiamonds (B-DNDs)âExecutive Summary
Section titled âExecutive SummaryâThis paper validates the theoretical potential for creating semiconducting nanodiamonds (NDs) by successfully achieving stable substitutional boron doping in detonation-derived nanodiamonds (DNDs) of sub-5 nm dimensions.
- Core Scientific Breakthrough: Experimental evidence confirms that substitutional boron doping is achievable in nm-scale DND cores, overturning previous theoretical doubts regarding instability or surface aggregation.
- Electrical Characterization: Impedance Spectroscopy (IS) measurements confirm two distinct conduction paths, revealing characteristic thermal activation energies (Ea) associated with different doping levels.
- Doping Confirmation: Evidence supports both moderately doped particles (~1017 B cm-3, acting as semiconductors) and heavily doped particles (~1020 B cm-3, exhibiting quasi-metallic behavior via an impurity band).
- Device Application Potential: The confirmation of stable semiconducting properties in ultra-small B-DNDs opens significant pathways for advanced nanodiamond electronics, high surface area electrochemistry, and highly dense seeding applications.
- Methodological Validation: Multiple complementary characterization techniques (IS, HR-TEM, Raman, CL, PL, FTIR) were successfully employed to confirm the structural and electrical characteristics of the sub-5 nm B-DNDs.
- Relevance to 6CCVD: This research underscores the fundamental importance of highly controlled boron incorporation in diamond materials, directly aligning with 6CCVDâs expertise in producing high-quality, scalable Boron-Doped Diamond (BDD) substrates for subsequent device fabrication.
Technical Specifications
Section titled âTechnical SpecificationsâHard data extracted from the impedance spectroscopy and material characterization results.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| DND Size Range (Nominal) | 3-4 | nm | Detonation synthesis source. |
| Doping Level (Moderate) | ~1 x 1017 | B cm-3 | Associated with semiconducting behavior. |
| Doping Level (Heavy) | ~1 x 1020 | B cm-3 | Associated with quasi-metallic behavior. |
| High Activation Energy (Ea, high) | ~0.8 | eV | Conduction path observed at 300 °C-450 °C. |
| Low Activation Energy (Ea, low) | ~0.02 (or 20-30) | eV (meV) | Conduction path observed below 200 °C. |
| IS Frequency Range | 0.1 Hz - 10 MHz | - | Used for Cole-Cole plot generation. |
| IS Temperature Range | 20 - 500 | °C | Used for Arrhenius plots (Ea determination). |
| HR-TEM Lattice Spacing (111) | 0.206 | nm | Undoped diamond cores. |
| HR-TEM Lattice Spacing (Doped) | Up to 0.213 | nm | Indicates presence of dopants (B/N). |
| Cathodoluminescence Temp | 95 | K | Used to observe free and bound excitons. |
| Experimental Pellet Size | 11 mm x 3 mm | Diameter x Thickness | Used for solid-state Impedance Spectroscopy. |
Key Methodologies
Section titled âKey MethodologiesâA summary of the preparation and characterization techniques used for the B-DNDs.
- Material Sourcing & Preparation:
- B-DND powder (3-4 nm, detonation-derived) was used, suspended in DI water at 0.05 g/L concentration.
- Solution was ultra-sonicated at 40% power for 5 hours.
- Substrate Seeding (CVD Prep):
- DNDs were seeded on RCA-cleaned or H-terminated silicon substrates (prepared using Seki Technotron AX1010 MPCVD system at 20 mbar, 800 °C for 20 minutes) via immersion and ultrasonic bath treatment (3 minutes).
- Pellet Fabrication (IS Samples):
- Dry B-DND powder was compacted using a mechanical press (10T weight) to create solid round pellets (11 mm diameter, 3 mm thick).
- Surface Functionalization:
- Ozone Treatment: Produced O-terminated DNDs (50 mbar, 200 °C, 3 hours).
- Hydrogen Treatment: Produced H-terminated DNDs (H2 atmosphere, 10 mbar, 700 °C, 5 hours).
- Electrical Characterization (IS):
- Impedance Spectroscopy was performed in a stainless steel vacuum vessel (20 °C-500 °C) using a Solartron 1260/1296 system over 0.1 Hz-10 MHz.
- Structural and Compositional Analysis:
- HR-TEM (Joel-2100, 200kV) and CL (95 K, 100kV) were used for structure and excitonic analysis.
- AFM (Bruker Icon, tapping mode) measured aggregate and particle size on seeded Si substrates.
- Raman Spectroscopy (Renishaw Invia, 532 nm, 150 mW) confirmed diamond and graphitic phases.
- FT-IR/ATR Spectroscopy analyzed surface termination/functional groups (O-H, C=C, C-H).
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThis research successfully demonstrates that stable substitutional boron doping is possible in diamond nanoparticles. While the paper focuses on ultra-small detonation NDs, the findings directly inform and validate the need for high-quality, tailored Boron-Doped Diamond (BDD) materials for scalable device engineering, which is 6CCVDâs core specialization.
Applicable Materials and Substrates
Section titled âApplicable Materials and SubstratesâTo replicate or extend this research into functional large-scale devices (e.g., high-performance electrodes, heat sinks, or sensing platforms), researchers require high-quality CVD-grown BDD.
| Research Requirement | 6CCVD Recommended Material | Technical Advantage |
|---|---|---|
| Substitutional B-Doping Validation | Boron-Doped Diamond (BDD) Wafers | CVD BDD offers highly controlled, uniform substitutional doping (p-type semiconductor or quasi-metallic/superconducting) for reliable electronic scaling. |
| Electrode & Device Fabrication | PCD Plates (Up to 125 mm) | Enables manufacturing high surface area BDD electrodes or electronic components far larger than the nm-scale pellets used in the study. |
| Specific Crystal Orientation/Purity | Optical Grade SCD (Low N) | Necessary for quantum applications or high-fidelity CL/PL studies where low nitrogen and high crystal quality are paramount. |
| Seeding Material (High Density) | Polished SCD Substrates | Can provide ultra-smooth (Ra < 1nm) starting wafers for subsequent homoepitaxial growth of BDD films, eliminating the highly resistive interfacial layer noted in the paper (Ref 13). |
Customization Potential for Nanodiamond Electronics
Section titled âCustomization Potential for Nanodiamond ElectronicsâThe experiments required specific sample geometries (11 mm pellets) and utilized various interfaces for electrical testing (IS) and structural analysis (AFM/TEM grids). 6CCVD specializes in providing materials that meet precise engineering demands:
- Custom Dimensions and Shapes: While the paper used small pellets, 6CCVD routinely provides MPCVD diamond (SCD or PCD) wafers and plates up to 125 mm in size. We offer precision laser cutting and shaping services to produce non-standard geometries or contact patterns required for complex IS or device testing rigs.
- Engineered Surfaces: The paper required ultra-smooth surfaces for AFM (SiO2-Si substrate) and highly controlled polishing for thin film studies. 6CCVD guarantees superior polishing, offering Ra < 1nm for SCD and Ra < 5nm for inch-size PCD, critical for reliable contact deposition and film uniformity.
- Integrated Metalization Schemes: AC Impedance Spectroscopy often requires stable, low-resistance ohmic contacts. 6CCVD offers in-house metalization capability, including deposition of common schemes like Ti/Pt/Au, Au, Pd, or W, tailored to the customerâs specified thickness and pattern, ensuring robust electrical integration.
Engineering Support
Section titled âEngineering SupportâThe successful incorporation of boron into nanodiamonds at precise concentrations requires meticulous control of the CVD process, gas ratios, and subsequent surface termination treatments (O-terminated or H-terminated).
6CCVDâs in-house PhD team possesses deep expertise in MPCVD growth parameters, doping control, and post-processing. We can assist engineers and scientists working on:
- Scaling up nanodiamond seeding processes.
- Developing highly conductive BDD interfaces for electrochemistry and fuel cells.
- Selecting appropriate BDD doping levels (from heavily doped quasi-metallic to lightly doped semiconducting) for specific electronic sensor or device applications.
- Optimizing diamond thickness (0.1”m to 500”m for thin films, up to 10mm for substrates) to meet precise device resistance and thermal management specifications.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly. We offer global shipping (DDU default, DDP available) to accelerate your research and development timeline.
View Original Abstract
Abstract The inclusion of boron within nanodiamonds to create semiconducting properties would create a new class of applications in the field of nanodiamond electronics. Theoretical studies have differed in their conclusions as to whether nm-scale NDs would support a stable substitutional boron state, or whether such a state would be unstable, with boron instead aggregating or attaching to edge structures. In the present study detonation-derived NDs with purposefully added boron during the detonation process have been studied with a wide range of experimental techniques. The DNDs are of ~4 nm in size, and have been studied with CL, PL, Raman and IR spectroscopies, AFM and HR-TEM and electrically measured with impedance spectroscopy; it is apparent that the B-DNDs studied here do indeed support substitutional boron species and hence will be acting as semiconducting diamond nanoparticles. Evidence for moderate doping levels in some particles (~10 17 B cm â3 ), is found alongside the observation that some particles are heavily doped (~10 20 B cm â3 ) and likely to be quasi-metallic in character. The current study has therefore shown that substitutional boron doping in nm NDs is in fact possible, opening-up the path to a whole host of new applications for this interesting class of nano-particles.