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Research on Application of diamond MOSFET in DCDC converter

MetadataDetails
Publication Date2025-01-15
JournalApplied and Computational Engineering
AuthorsRuitong Gao
InstitutionsJilin University
AnalysisFull AI Review Included

Research on Application of Diamond MOSFET in DCDC Converter: Technical Analysis

Section titled “Research on Application of Diamond MOSFET in DCDC Converter: Technical Analysis”

This research proposes integrating Diamond MOSFETs into DC-DC (DCDC) converters to overcome the inherent performance limitations of current Silicon (Si) and wide-bandgap (WBG) materials like Silicon Carbide (SiC) and Gallium Nitride (GaN).

  • Core Value Proposition: Diamond, the “ultimate semiconductor,” offers superior material properties (highest thermal conductivity, largest band gap, highest breakdown field) necessary for next-generation power electronics.
  • Performance Targets: Application of Diamond MOSFETs is expected to significantly improve DCDC converter operating frequency, input/output voltage range, output power density, and overall efficiency.
  • Key Material Metrics: Diamond boasts a 5.47 eV band gap and an insulation strength 33 times that of silicon, enabling high-temperature and high-pressure operation.
  • Device Achievements: Recent breakthroughs include achieving a breakdown voltage up to 3659 V and developing the world’s first N-type channel-driven diamond MOSFET (2024), addressing historical doping challenges.
  • Current Limitation: Industrial mass production is currently hindered by high production costs and immature growth processes for high-quality, large-scale diamond material.
  • Proposed Methodology: Future research should leverage the mature application models of SiC/GaN in DCDC circuits, utilizing simulation tools (Simulink/Simscape) for loss analysis and redesigning drive circuits to match diamond device limits.

The following table summarizes key material properties and device performance metrics extracted from the research, highlighting diamond’s superiority over conventional semiconductors.

ParameterValueUnitContext
Band Gap Width5.47eVPure diamond semiconductor
Breakdown Electric Field (Relative)~10timesCompared to GaN
Breakdown Electric Field (Relative)~3timesCompared to SiC
Insulation Strength (Relative)33timesCompared to Silicon
Maximum Breakdown Voltage3659VP-type doped diamond MOSFET (2020)
Figure of Merit (FOM)> 673V¡mS/mmHydrogen terminal diamond device (2022)
External Transconductance65mS/mmSingle crystal diamond device (50 nm gate length)
Intrinsic Transconductance650mS/mmSingle crystal diamond device (50 nm gate length)
Saturation Leakage Current290mA/mmSingle crystal diamond device (50 nm gate length)
Thermal Stability (Proven)200°CHigh-performance diamond MOSFET operation
Largest Single Crystal Size10mmReported CVD single crystal side length (China)

The research outlines both historical fabrication achievements and the proposed engineering methodology for integrating Diamond MOSFETs into DCDC converters.

  • CVD Growth: Focus on Chemical Vapor Deposition (CVD) techniques to achieve large-side-length single crystal diamond materials (up to 10 mm reported).
  • Gate Dielectric Deposition: Alumina films were deposited on hydrogen-ended diamond surfaces, enabling MOSFET operation under vacuum at 450 °C.
  • N-Type Doping Breakthrough: Recent efforts focus on creative breakthroughs in obtaining impurity elements and doping methods necessary for low-resistivity N-type diamond channels.
  • Performance Optimization: Development of devices using MoO3 gate media resulted in reducing on-resistance to one-third and increasing transconductance by approximately three times compared to world-equivalent gate-long devices.

The suggested path for applying diamond MOSFETs involves simulation and loss analysis, learning from established WBG integration:

  1. Analogous Application: Use the mature application mode of SiC or GaN MOSFETs in DCDC converters as a blueprint for diamond integration.
  2. Circuit Simulation: Utilize Simulink and the Simscape Electrical component library for initial circuit modeling.
  3. Topology Selection: Build the LLC resonant converter simulation diagram based on laboratory parameters for high-voltage, high-power diamond MOSFETs.
  4. Parameter Analysis: Analyze how diamond MOSFET parameters (operating frequency, on-resistance, voltage tolerance) affect converter output characteristics (efficiency, switching loss, power density).
  5. Detailed Loss Analysis: Calculate the loss of the built circuit, separating contributions from:
    • Switching tube loss (conduction and switching losses).
    • Rectifier diode loss.
    • Magnetic component loss.
  6. Drive Circuit Redesign: Redesign the drive circuit structure to optimally match and utilize the limiting performance characteristics of the diamond power devices.

Diamond MOSFET technology is positioned to disrupt several high-demand sectors currently limited by silicon and first/second-generation WBG materials.

  • High-Power Conversion Systems:
    • DCDC Converters requiring high output power, high efficiency, and miniaturization.
    • Advanced Switching Power Supplies (high power density development).
  • Transportation and Energy:
    • New Energy Vehicles (requiring high reliability and high output power components).
  • Data and Communications Infrastructure:
    • Base Stations (5G/6G technology).
    • Data Centers (high current and high efficiency requirements).
  • Extreme Environment Electronics:
    • High-temperature and high-pressure applications where SiC/GaN performance degrades.
    • Radiation-resistant integrated circuits.
  • Specialized High-Frequency Devices:
    • Millimeter wave amplifiers.
    • Anti-radiation device materials.
View Original Abstract

This paper focuses on the industrial application of diamond power devices and DCDC converters, carries out the application research of diamond MOSFET in DCDC converters, analyzes the limitations of current silicon-based DCDC converters and how diamond MOSFET should make up for this limitation. This paper summarizes the research on the practical application of diamond power devices at home and abroad and points out that there is a gap in the application of diamond MOSFETs in DCDC converters. Diamond has the advantages of a large band gap, high carrier mobility, high temperature and high pressure resistance, so the application of diamond MOSFET in a DCDC converter can improve its operating frequency, input and output voltage and efficiency. This paper also discusses the difficulties encountered by diamond semiconductor materials and diamond power devices in the research and industrial fields, as well as the research status of diamond semiconductor materials at home and abroad, and gives the research method for the future application of diamond MOSFET in DCDC converters. The study can use the analogy of applying SiC or GaN to DCDC converters improving their performance, and redesigning the drive circuit to match the limiting performance of diamond power devices. By applying diamond MOSFET into the DCDC converter, its operating voltage, operating frequency, output power and efficiency will be greatly improved.