Characterization of Carbon Thin Films Prepared by High Power Impulse Magnetron Sputtering
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2017-01-01 |
| Journal | Journal of the Vacuum Society of Japan |
| Authors | Norio Nawachi, Koichi Itoh, Yosuke ISAGI, Yoshiaki Yoshida, Keishi Okamoto |
| Institutions | Okayama University of Science, Toyo Engineering (Japan) |
| Analysis | Full AI Review Included |
6CCVD Technical Documentation: High-Performance Carbon Films via Advanced PVD Methods
Section titled â6CCVD Technical Documentation: High-Performance Carbon Films via Advanced PVD MethodsâDocument Reference: Analysis of âCharacterization of Carbon Thin Films Prepared by High Power Impulse Magnetron Sputteringâ Subject: High Hardness, High Density Diamond-Like Carbon (DLC) Film Structure and Optimization Applicable 6CCVD Materials: Single Crystal Diamond (SCD), Polycrystalline Diamond (PCD), and Boron-Doped Diamond (BDD)
Executive Summary
Section titled âExecutive SummaryâThis research leverages High Power Impulse Magnetron Sputtering (HiPIMS) combined with Multipolar Magnetic Plasma Confinement (MMPC) to produce highly dense and hard carbon films. This advanced deposition technique and the focus on optimizing carbon structure align directly with 6CCVDâs core expertise in ultra-hard, customized diamond materials.
- Structure Optimization: The HiPIMS-MMPC method successfully promotes the formation of tetrahedral amorphous carbon (ta-C) structure, deemed more effective than the graphitic (nc-G) structure produced by standard HiPIMS.
- Superior Performance: DLC films achieved a maximum hardness of approximately 20 GPa and a maximum density of 2.00 g/cm3.
- Method Efficacy: The inclusion of MMPC significantly increased plasma density near the substrate, improving ion bombardment and yielding denser, harder films, despite a corresponding reduction in deposition rate (less than half that of standard HiPIMS).
- High Power Recipe: The optimized recipe utilized a high peak power density of 690 W/cm2 at a low 1% duty cycle.
- 6CCVD Relevance: While this paper focuses on DLC, 6CCVD specializes in MPCVD diamond, which offers intrinsic hardness (typically >90 GPa) and density far exceeding these films, eliminating the structural compromises inherent in amorphous carbon materials.
- Application Crossover: The need for materials exhibiting extreme hardness and controlled density highlights applications requiring superior wear resistance, precision optics, and advanced electronic interfacesâareas where 6CCVDâs custom SCD and PCD excel.
Technical Specifications
Section titled âTechnical SpecificationsâThe following table summarizes the critical material properties and processing parameters extracted from the research paper.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Maximum Hardness (HiPIMS-MMPC) | 20 | GPa | Achieved at various biases |
| Maximum Density (HiPIMS-MMPC) | 2.00 | g/cm3 | Bias Voltage: -200 V |
| Target Material | Graphite | (99.99% purity) | Diameter: 210 mm, Thickness: 5 mm |
| Substrate Material | Silicon | Si | Depositions conducted at room temperature |
| Gas Atmosphere | Argon | Ar | |
| Chamber Pressure | 0.5 | Pa | Standard deposition pressure |
| Target Voltage (Applied) | -900 | V | Fixed setting for pulse |
| Maximum Peak Current | 633 | A | HiPIMS-MMPC, 1% Duty Cycle |
| Peak Power Density | 690 | W/cm2 | Calculated for 1% Duty Cycle |
| Optimized Duty Cycle | 1 | % | Used for stable plasma discharge |
| Frequency | 200 | Hz | Pulse repetition rate |
| Pulse Duration | 50 | ”s | Fixed pulse width |
| Substrate Bias Voltages | -100, -200, -300 | V | Used to control ion energy and structure |
| Max Surface Roughness (Rz) | 5.6 | nm | HiPIMS-MMPC, Bias -300 V |
| Max Deposition Rate (HiPIMS-MMPC) | 11.0 | nm/min | Bias -300 V (Half the rate of standard HiPIMS) |
Key Methodologies
Section titled âKey MethodologiesâThe experimental setup utilized two carbon film preparation methods for comparison: standard HiPIMS and HiPIMS combined with Multipolar Magnetic Plasma Confinement (HiPIMS-MMPC). The critical steps and recipe parameters are listed below:
- System Setup: A graphite target was used with a high-power DC source (iPulse10000). The HiPIMS-MMPC system incorporated permanent magnets (Nd-Fe-B) both behind the target and on the target sides to concentrate and draw the plasma toward the silicon (Si) substrate.
- Atmosphere Control: Depositions were conducted in an Argon (Ar) gas atmosphere maintained at a constant pressure of 0.5 Pa.
- High Power Pulse Parameters: A critical, stable discharge was achieved using the following fixed parameters:
- Applied Target Voltage: -900 V.
- Duty Cycle: 1% (optimized for stability and high peak power).
- Frequency: 200 Hz.
- Pulse Duration: 50 ”s.
- Structural Control: Substrate bias voltages (-100 V, -200 V, -300 V) were applied to the Si wafers to accelerate incident ions, promoting the necessary subsurface collision cascade required for forming the dense, hard ta-C (tetrahedral amorphous carbon) structure, as confirmed by Raman analysis (stable I(D)/I(G) ratio near 1.0).
- Characterization: The resulting carbon films were analyzed rigorously for performance metrics:
- Structure: Raman Spectroscopy (identifying D-band and G-band characteristics).
- Hardness: Nanoindentation (Hysitron Triboscope).
- Density: X-ray Reflectometry (XRR).
- Morphology: Stylus Profilometry (Rz and deposition rate).
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThis research demonstrates a sophisticated approach to creating high-performance carbon films under controlled plasma conditions. 6CCVD specializes in bulk, single-phase crystalline diamondâthe ultimate carbon materialâgrown via MPCVD, providing engineering solutions that offer superior hardness, thermal conductivity, and chemical inertness for demanding applications.
Applicable Materials
Section titled âApplicable MaterialsâThe requirements for extreme hardness and density observed in this paper are ideally met and surpassed by 6CCVDâs catalog of MPCVD diamond materials:
| Required Application Feature | 6CCVD Material Recommendation | Rationale |
|---|---|---|
| Extreme Hardness & Wear Resistance | SCD (Single Crystal Diamond) | Intrinsic hardness >90 GPa. Available in optical and electronic grades. |
| High Density & Uniformity | PCD (Polycrystalline Diamond) | High consistency, large area coverage up to 125mm. Highly competitive cost-to-performance ratio for mechanical applications. |
| Conductivity & Electrochemistry | Boron-Doped Diamond (BDD) | Achieves high conductivity, suitable for electrode applications, potentially replacing high-density DLC in conductive/sensing environments. |
| Advanced Interface Layers | Optical Grade SCD | Substrates or windows up to 500”m thick, offering unparalleled purity and surface finish (Ra < 1nm). |
Customization Potential
Section titled âCustomization PotentialâThe PVD techniques explored in the paper focus on achieving optimized interfaces and density on substrates. 6CCVD offers extensive customization capabilities critical for integrating high-performance diamond materials into complex systems:
- Custom Dimensions: We offer PCD and SCD plates/wafers with custom shapes and dimensions, with PCD available up to 125 mm in diameter, exceeding typical research dimensions.
- Thickness Control: Precision control allows for film thickness from 0.1 ”m to 500 ”m for both SCD and PCD layers, as well as thick substrates up to 10 mm.
- Ultra-Low Roughness Polishing: Achieving low roughness is key for reducing friction and scattering. 6CCVD guarantees surface finishes of Ra < 1 nm for SCD and Ra < 5 nm for inch-size PCD, significantly surpassing the Rz=5.6 nm observed in the analyzed DLC films.
- Integrated Metalization: 6CCVD provides in-house metalization services, including common electrode and bonding layers such as Au, Pt, Pd, Ti, W, and Cu, allowing researchers to directly integrate our diamond into complex devices, potentially leveraging PVD techniques like those described here for interface preparation.
Engineering Support
Section titled âEngineering SupportâThe challenges described in optimizing the ta-C structure via plasma density control are analogous to the challenges 6CCVDâs experts solve daily in controlling nitrogen inclusion, crystal orientation, and defect density in MPCVD diamond growth. 6CCVDâs in-house PhD engineering team can assist with material selection, interface design, and dimensional specification for similar high-wear, high-density, or advanced semiconductor projects, ensuring optimal performance from initial concept through final fabrication.
Call to Action
Section titled âCall to Actionâ6CCVD ships high-quality MPCVD diamond globally, simplifying procurement through DDU (default) and DDP shipping options. For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
The characteristics of diamond-like carbon (DLC) films deposited by high power impulse magnetron sputtering (HiPIMS) with multipolar magnetic plasma confinement (MMPC) were investigated. DLC films were prepared on silicon (Si) by HiPIMS and HiPIMS-MMPC over varying substrate bias voltage. Depositions were performed from a graphite target (210 mm in diameter) under argon (Ar) gas atmosphere at chamber pressure of 0.5 Pa. The DLC films were analyzed by several methods. In HiPIMS-MMPC, the peak power density was approximately 690 W/cm2 at a duty cycle of 1% (frequency: 200 Hz). According to Raman spectroscopy, the structure of DLC film deposited by HiPIMS-MMPC could be changed from amorphous carbon (a-C) to tetrahedral amorphous carbon (ta-C). The deposition rate in HiPIMS-MMPC was approximately 50% (10 nm/min) lower than that in HiPIMS. However, HiPIMS-MMPC is considered as one of the effective methods to prepare hard and dense DLC films (20 GPa and 2.00 g/cm3 at the maximum).