The need to mitigate climate change is driving a need to electrify our infrastructure, vehicles, and appliances, which can then be charged and powered by renewable energy sources. The most visible and impactful electrification is now under way for electric vehicles (EVs). Beyond the transition to electric engines, several new features and technologies are driving the electrification of vehicles. The number of sensors in a vehicle is skyrocketing, driven by autonomous driving and other safety features, while a modern software-defined vehicle (SDV) is electrifying everything from air-conditioned seats to self-parking technology.

An important technology for EVs and SDVs is power modules. These are super high-voltage devices that convert one form of electricity to another (e.g., AC to DC), which is necessary to convert the vehicle battery energy to a current that can run the vehicles electrical system, including the drive train. These modules demand the highest power loads and are rated at 1000s of voltages – and the design of power devices, which are the fundamental electronic component of the power modules, is crucial, as a bad design can lead to catastrophe events.

Power devices, much more than other types of electrical devices, are designed for specific applications. In comparison, logic transistors can be used in everything from toasters to smartphones. Not only does the architecture of power devices change at higher voltages, different power ratings, or higher switching frequencies as needed, but the material can change as well.

New power requirements need wide-band gap materials

To meet new and future power demands for EVs, electric infrastructure, and other novel electrical systems, wide-band gap (WBG) materials are being developed and introduced. Silicon carbide (SiC) IGBTs are now available and being deployed, while gallium arsenide (GaN) HEMTs are a promising technology that is in the development stage.

Power density vs. switching frequency of power devices based on different materials.

Continuing with our EV example, SiC inverters can generally increase the potential range by approximately 10%, even after accounting for other design considerations. In addition, increasing the drive train voltage from 400V range to 800V can reduce the charging speeds by half. These voltages are only possible to realize with wide-band gap materials like SiC-based power devices. Tesla introduced SiC MOSFETs into its Model S back in 2018. Since then, numerous automotive manufacturers have also adopted SiC in their EVs, including Hyundai and BMW, for example.

GaN still has many design hurdles to overcame to improve reliability and decrease cost – but if it can be made affordable, perhaps the next realization of EVs will allow for charging in seconds with ranges of thousands of miles.

Simulating power devices

Because of the huge number of design parameters, simulation is important in the design of power devices. One crucial part for device design is the calculation of the breakdown voltage – the voltage at which the device can essentially melt, or catch fire, but will never operate again. These simulations need to be highly physics-based and capture the mechanisms by which electrons can be released or absorbed by the crystal lattice of these materials. The increasing band gaps in WBG materials like SiC and GaN increase the breakdown voltage. In addition, these materials have a smaller effective electron mass (i.e., the mass of an electron in a material dictates how fast it will move in an electric field) – which makes the switching frequency in devices based on these WBG materials faster.

A critical area of all electronics design is variability and reliability. Device performance needs to be stable and last a long time. A key factor for variability and reliability is defects in the crystal lattice. These defects, or traps, act as charge centers that can drastically impact how well a device works. Simulation can also help to identify the types of traps, providing a mechanistic understanding of how the traps will impact the device physics. Recently, Synopsys issued a paper using first-principles quantum solutions to characterize specific traps in SiC with QuantumATK.

Going forward, wind energy, solar, home appliances, and even the electric grid itself are going to need new devices with different structures and materials. The future is extremely exciting for power devices, which can be found in our EVs and will soon power a huge range of applications across our society.

The post Enabling New Applications With SiC IGBT And GaN HEMT For Power Module Design appeared first on Semiconductor Engineering.

The need to mitigate climate change is driving a need to electrify our infrastructure, vehicles, and appliances, which can then be charged and powered by renewable energy sources. The most visible and impactful electrification is now under way for electric vehicles (EVs). Beyond the transition to electric engines, several new features and technologies are driving the electrification of vehicles. The number of sensors in a vehicle is skyrocketing, driven by autonomous driving and other safety features, while a modern software-defined vehicle (SDV) is electrifying everything from air-conditioned seats to self-parking technology.

An important technology for EVs and SDVs is power modules. These are super high-voltage devices that convert one form of electricity to another (e.g., AC to DC), which is necessary to convert the vehicle battery energy to a current that can run the vehicles electrical system, including the drive train. These modules demand the highest power loads and are rated at 1000s of voltages – and the design of power devices, which are the fundamental electronic component of the power modules, is crucial, as a bad design can lead to catastrophe events.

Power devices, much more than other types of electrical devices, are designed for specific applications. In comparison, logic transistors can be used in everything from toasters to smartphones. Not only does the architecture of power devices change at higher voltages, different power ratings, or higher switching frequencies as needed, but the material can change as well.

New power requirements need wide-band gap materials

To meet new and future power demands for EVs, electric infrastructure, and other novel electrical systems, wide-band gap (WBG) materials are being developed and introduced. Silicon carbide (SiC) IGBTs are now available and being deployed, while gallium arsenide (GaN) HEMTs are a promising technology that is in the development stage.

Power density vs. switching frequency of power devices based on different materials.

Continuing with our EV example, SiC inverters can generally increase the potential range by approximately 10%, even after accounting for other design considerations. In addition, increasing the drive train voltage from 400V range to 800V can reduce the charging speeds by half. These voltages are only possible to realize with wide-band gap materials like SiC-based power devices. Tesla introduced SiC MOSFETs into its Model S back in 2018. Since then, numerous automotive manufacturers have also adopted SiC in their EVs, including Hyundai and BMW, for example.

GaN still has many design hurdles to overcame to improve reliability and decrease cost – but if it can be made affordable, perhaps the next realization of EVs will allow for charging in seconds with ranges of thousands of miles.

Simulating power devices

Because of the huge number of design parameters, simulation is important in the design of power devices. One crucial part for device design is the calculation of the breakdown voltage – the voltage at which the device can essentially melt, or catch fire, but will never operate again. These simulations need to be highly physics-based and capture the mechanisms by which electrons can be released or absorbed by the crystal lattice of these materials. The increasing band gaps in WBG materials like SiC and GaN increase the breakdown voltage. In addition, these materials have a smaller effective electron mass (i.e., the mass of an electron in a material dictates how fast it will move in an electric field) – which makes the switching frequency in devices based on these WBG materials faster.

A critical area of all electronics design is variability and reliability. Device performance needs to be stable and last a long time. A key factor for variability and reliability is defects in the crystal lattice. These defects, or traps, act as charge centers that can drastically impact how well a device works. Simulation can also help to identify the types of traps, providing a mechanistic understanding of how the traps will impact the device physics. Recently, Synopsys issued a paper using first-principles quantum solutions to characterize specific traps in SiC with QuantumATK.

Going forward, wind energy, solar, home appliances, and even the electric grid itself are going to need new devices with different structures and materials. The future is extremely exciting for power devices, which can be found in our EVs and will soon power a huge range of applications across our society.

The post Enabling New Applications With SiC IGBT And GaN HEMT For Power Module Design appeared first on Semiconductor Engineering.

For more than half a century, silicon has been the bedrock of power electronics. Yet as silicon meets its physical limitations in higher-power, higher-temperature applications, the industry’s relentless pursuit of more efficient power systems has ushered in the wide bandgap (WBG) semiconductors era. The global WBG semiconductors market reached $1.6 billion in 2022, with an estimated CAGR of $13% for the next 8-year period. The adoption of WBG semiconductors, notably silicon carbide (SiC) and gallium nitride (GaN), is now setting new benchmarks for performance in power systems across automotive, industrial, and energy sectors. What impact will WBG semiconductors have on power electronics (PE) trends in 2024, and how are they redefining the design and simulation workflows for the next decade?

The catalyst for change: Wide bandgap

The term ‘bandgap’ refers to the energy difference between a material’s insulating and conducting states, a critical factor determining its electrical conductivity.

As shown in figure 1, with its wide bandgap, Gallium Nitride (GaN) exemplifies the three key advantages this property can offer.

Fig. 1: Wide bandgap semiconductor properties.

• Faster switching speeds: One of the most significant benefits of GaN’s wide bandgap is its contribution to faster switching speeds. The electron mobility in GaN is around 2,000 cm²/Vs, enabling switching frequencies up to 10 times higher than silicon. A higher switching speed translates into reduced switching losses, making the overall designs more compact and efficient.

Fig. 2: Switching speeds of SiC and GaN.

• Higher thermal resistance: With a thermal conductivity of 2 W/cmK, GaN can dissipate heat and operate at temperatures up to 200°C efficiently. This resilience enables more effective thermal management at high temperatures and extreme conditions.
• Higher voltages: With an electric breakdown field of 3.3 MV/cm, GaN can withstand almost 10 times silicon’s voltage.

GaN and other wide-bandgap semiconductors offer solutions for high-power, high-frequency, and high-temperature applications with improved energy efficiency and design flexibility.

Emerging challenges in power electronics simulation

The wider adoption of wide bandgap (WBG) semiconductors, including silicon carbide (SiC) and gallium nitride (GaN), sets new standards in the design of Switched Mode Power Supplies (SMPS) – power efficiency, compactness, and lighter weight.

However, the higher switching speeds of GaN and SiC demand more sophisticated design considerations. Power electronics engineers must manage electromagnetic interference (EMI) and optimize thermal performance to ensure reliability and functionality. Layout parasitics, for instance, can lead to voltage spikes in the presence of high di/dt values. Power electronics engineers face the following pressing questions:

• How can we guarantee reliability for mission-critical applications across a wider range of operating temperatures?
• What are the essential practices for understanding and predicting EMI and noise?
• What tools can we employ to create robust thermal models for comprehensive system-level analysis?

To navigate these complexities, engineers need advanced simulation solutions to address layout parasitic effects effectively and come with robust thermal analysis.

Fig. 3: Thermal analysis at board and schematic levels using Keysight’s PEPro.

Key impacts of WBG semiconductors: From EVs to renewable energy

Electric vehicles (EVs): As global EV sales are projected to increase by 21% in 2024, the power efficiency of automotive power electronics is paramount – every additional percentage is a big win. GaN enables more compact and efficient designs of onboard chargers and traction inverters, extending driving ranges by up to 6%.

Data centers: The digital economy’s expansion brings a surge in data center energy consumption, with the U.S. expected to require an additional 39 gigawatts over the next five years—equivalent to powering around 32 million homes. Wide bandgap semiconductors may be key to addressing this challenge by enabling higher server densities and reducing energy consumption and carbon emissions. Specifically, the implementation of GaN transistors in data center infrastructure can lead to a reduction of 100 metric tons of CO2 emissions for every 10 racks annually. This efficiency gain is particularly relevant as the computational and power demands of artificial intelligence (AI) applications soar, potentially tripling the racks’ power density.

Renewable energy: Wide bandgap semiconductors allow for more reliable power output and cost-effective solutions in both residential and commercial renewable energy storage systems. For instance, GaN transistors could achieve four times less power loss than traditional silicon-based power solutions.

The road ahead in the era of WBG semiconductors

GaN and SiC represent a new wave of material innovation to elevate the efficiencies of power electronics and redefine how we power our world. As the applications for WBG semiconductors expand, Keysight empowers our customers with a unified simulation environment to design reliable and long-lasting electronic systems under various operating conditions.

The post What’s Next For Power Electronics? Beyond Silicon appeared first on Semiconductor Engineering.