Silicon carbide (SiC), as a wide bandgap semiconductor material, has shown broad application prospects in the field of semiconductor devices due to its excellent physical properties, such as high breakdown electric field strength, high thermal conductivity, and high electron saturation drift velocity. SiC devices have significant advantages over traditional silicon-based devices as they can operate at higher temperatures, voltages, and frequencies. The following are the main types, characteristics, and applications of silicon carbide semiconductor devices currently available:
1. Silicon carbide Schottky diode (SiC SBD)
Schottky Barrier Diode (SBD) is one of the earliest SiC devices to achieve commercialization. For example, MBR6060R is a 600V, 6A silicon carbide Schottky diode produced by ON Semiconductor. It adopts advanced SiC technology, with extremely low forward voltage drop (typical value of 1.55V) and fast switching characteristics. Its most important feature is "zero reverse recovery current", which significantly reduces switching losses and makes it very suitable for high-frequency applications. In addition, it can operate stably in high temperature environments up to 175 ° C and has a high ability to withstand surge currents. These types of diodes are widely used in power factor correction (PFC) circuits and high-frequency DC-DC converters in industrial power supplies, server power supplies, communication equipment power supplies, solar inverters, and electric vehicle chargers, helping to improve system efficiency and power density.
2. Silicon carbide metal oxide semiconductor field-effect transistor (SiC MOSFET)
SiC MOSFET is a core device in the field of power electronics, suitable for high-frequency, high-voltage, and high-efficiency scenarios. For example, UU16LFNP-802 is a silicon carbide power MOSFET module produced by UnitedSiC (now Littelfuse), with a drain source voltage (Vds) of 1200V and a continuous drain current (Id) of up to 300A. It adopts a dual DIP package to support double-sided heat dissipation. SiC MOSFET has low on resistance (Rds (on)), fast switching speed, and low switching loss. Some new structures, such as the title 'Silicon Carbide SiC MOSFET Devices with Improved Gate Oxide Layer Reliability', effectively reduce the electric field strength at the SiO ₂ interface, decrease gate leakage current, suppress gate oxide layer degradation caused by hot carrier injection, and thus improve the reliability and lifespan of the device by using a high-K dielectric (such as hafnium dioxide, aluminum oxide, or zirconium dioxide) and SiO ₂ gate oxide layer to form a double-layer stacked structure. SiC MOSFET modules are particularly suitable for high-power, high-frequency power electronic systems such as electric vehicle charging equipment, photovoltaic inverters, energy storage converters, industrial motor drivers, and uninterruptible power supplies (UPS).
3. Silicon carbide power module
In order to meet the demands of higher power applications, silicon carbide devices often appear in modular form. These modules integrate multiple SiC MOSFETs and SiC SBDs (or freewheeling diodes) together, such as the automotive grade 750V/1200V SiC MOSFET module provided by Dahua Semiconductor, which has the advantages of low switching loss, strong avalanche resistance, and small temperature dependent on on on resistance. It is suitable for scenarios such as new energy vehicle main drive inverters and on-board chargers, and can improve energy conversion efficiency by more than 10%. Industrial grade products cover SiC diodes, MOSFETs, and modules ranging from 650V to 2000V, and are widely used in fields such as photovoltaic inverters, energy storage systems, and industrial power supplies. These modules adopt advanced packaging technology (such as CoWoS-L packaging) to optimize heat dissipation and interconnect performance.
4. Emerging applications of silicon carbide in advanced packaging
It is worth noting that the application of silicon carbide is expanding beyond traditional power devices to advanced packaging fields. Giants such as TSMC and NVIDIA are exploring the use of 12 inch monocrystalline silicon carbide for heat dissipation carriers and interposers to address the heat dissipation bottleneck of high-performance GPUs and AI chips. This mainly utilizes the extremely high thermal conductivity of silicon carbide (up to 400-500 W/mK, much higher than traditional materials). Among them, conductive SiC is preferred for heat dissipation board testing, while semi insulating SiC may be used to replace silicon intermediate layers to meet higher integration and heat dissipation requirements. Although this is not a traditional "device", it is indeed a promising new application direction for SiC materials in the semiconductor industry chain.
Overview of Application Fields
The superior characteristics of silicon carbide semiconductor devices make them play important roles in multiple key fields:
Electric vehicles (EV): It is one of the largest application markets for SiC devices, used in main drive inverters, on-board chargers (OBC), DC-DC converters, and charging stations, which can significantly improve energy efficiency, shorten charging time, and reduce system weight and volume.
Renewable energy: In solar inverters and energy storage systems (PCS), SiC devices can reduce energy conversion losses and improve system efficiency.
Industrial power supply: Used for uninterruptible power supplies (UPS), industrial motor drives, and switching power supplies, SiC devices can achieve higher power density and more efficient energy conversion.
High frequency communication: GaN HEMT devices prepared on semi insulating SiC substrates can be used for RF and microwave applications, such as 5G base stations, radar, and satellite communication.
Advanced computing and packaging: With the continuous increase in computing power density of AI chips, SiC, as a heat dissipation carrier and intermediate layer material, provides a new solution to solve chip heat dissipation problems.
Silicon carbide semiconductor devices mainly include Schottky diodes (SBDs), metal oxide semiconductor field-effect transistors (MOSFETs), and power modules composed of them. These devices, with their high-frequency, high-efficiency, high-pressure, and high-temperature working capabilities, are driving technological innovation in important fields such as electric vehicles, renewable energy, and industrial automation. At the same time, silicon carbide materials themselves have emerged as a new role in advanced packaging as a heat dissipation solution, demonstrating broad application prospects. With the continuous advancement of material growth, device design, and manufacturing processes (such as the development of larger 8-inch or even 12 inch substrates), the performance of silicon carbide devices will be further improved, costs are expected to continue to decrease, and their application scope will continue to expand.
