SiC product reliability assessment and supplier support measures need to be reviewed in detail.

Demand for silicon carbide (SiC) technology, which maximizes power system efficiency while reducing size, weight, and cost, continues to grow. However, SiC products are not drop-in replacements for silicon (Si), and not all products are created equal.

Realizing the potential of SiC technology requires careful evaluation of product and supplier options based on quality, supply, and support, as well as an understanding of how to optimize the integration of innovative SiC power components and end systems.

◇ Increasing adoption of SiC technology

Adoption of SiC technology has been increasing recently. Product availability has also increased as multiple suppliers offer a variety of products. The SiC market has doubled in size over the past three years and is projected to grow 20-fold over the next decade, reaching $10 billion.

SiC technology is being adopted not only in onboard hybrid and electric vehicle (H/EV) applications, but also in non-automotive power and motor control systems, including trains, heavy-duty vehicles, industrial equipment, and EV charging infrastructure. Aerospace and defense suppliers are also striving to enhance SiC quality and reliability to meet the demanding component robustness requirements of these industries.

A key element in leveraging SiC technology is verifying the reliability and robustness of SiC products. The level of this verification varies by supplier. With the trend toward a total system focus, developers must also evaluate the range of SiC product lines offered by suppliers. Choose a company that offers global distribution, comprehensive design simulation and development tools, and a variety of die/individual/module options.

We also need to consider emerging technologies such as digital programmable gate drivers, which address existing implementation challenges while allowing for easy system performance tuning.

◇ Three criteria for evaluating the reliability of SiC products

The reliability of SiC products can be determined by ▲avalanche capabilities ▲short circuit durability ▲SiC MOSFET body diode forward voltage stability.

Among the three criteria, avalanche durability evaluation is particularly important. If a passive component malfunctions and the rated breakdown voltage is exceeded, a momentary voltage spike can occur, potentially causing the SiC product to fail. This can lead to complete system failure.

SiC MOSFETs with sufficient avalanche tolerance reduce the need for snubber circuits and extend application life. Top-rated devices exhibit significantly higher UIS levels, reaching up to 25 J/cm2. These devices exhibit minimal parameter degradation even after 100,000 cycles of repeated UIS testing.

The second criterion, short-circuit endurance, is measured by measuring the short-circuit withstand time (SCWT), or the maximum time until product failure occurs under a rail-to-rail short-circuit condition. The measured results should be close to the values for IGBTs used in power conversion applications. Most IGBTs have an SCWT of 5 to 10 microseconds (μs). Having sufficient SCWT allows fault conditions to be repaired without causing damage to the system.

The third indicator, the forward voltage stability of the SiC MOSFET's intrinsic body diode, can vary significantly across suppliers. Improper product design, processing, or material selection can lead to reduced diode conductivity during operation, resulting in higher on-resistance.


A study conducted at Ohio State University evaluated MOSFETs from three suppliers. The graph on the right shows that all of Company B's products exhibited performance degradation in forward current, while Company C's MOSFETs exhibited no degradation.

After verifying product reliability, the next step is to evaluate the ecosystem surrounding these products. This includes a wide range of product options, a robust supply chain, and design support.

◇ Supply, support, and system-level design

As the number of SiC product suppliers increases, the gap between companies in terms of product supply and support experience, infrastructure, and device options in SiC markets such as automotive, aerospace, and defense is widening.

Power system design evolves over time through multiple generations, and so do SiC applications. Initial products utilize widely available standard discrete power products in standard through-hole and surface-mount package options.

As the number of applications grows and the focus shifts to reducing size, weight, and cost, developers are migrating their designs to integrated power modules or engaging in external partnerships. These external partners include end-product design teams, module manufacturers, and SiC die suppliers, each of which plays a critical role in achieving overall design goals.

Supply chain issues are a major concern and concern in the rapidly growing SiC market. SiC substrate material is the most expensive component in SiC die manufacturing. Furthermore, SiC manufacturing requires high-temperature assembly equipment not required for silicon-based products or IC development.

Developers should ensure that their SiC supplier has multiple manufacturing locations and a robust supply chain model to continuously meet demand in the event of natural disasters or major yield issues. Furthermore, with many suppliers discontinuing older products, developers may be forced to invest time and resources in redesigning existing applications instead of developing new designs that could reduce end-product costs and increase profits.

Design support, such as simulation tools and reference designs that reduce development time, is also important. Features such as augmented switching can also be applied to SiC product control/drive solutions to realize the full value of a total system approach.


Above is a SiC-based system reference with integrated programmable digital gate drivers that creates new design optimization methods and reduces production time.

◇ New options to consider for design optimization

The digitally programmable gate driver option maximizes the SiC effect through augmented switching. The on/off frequency and voltage level of the SiC MOSFET can be easily configured, increasing switching speed and system efficiency while reducing gate driver development time and complexity. Developers can easily optimize SiC-based designs using configuration software without having to manually modify the PCB one by one.

As applications adopting SiC grow, early adopters are already reaping the benefits in the automotive, industrial, aerospace, and defense sectors. The success of SiC adoption hinges on the ability to verify the reliability and robustness of SiC devices.

As developers adopt a total solution strategy, they need access to a comprehensive portfolio of complete and reliable global supply chains and all the necessary simulation and development tools. A new feature, software-configurable design optimization, will also unlock new opportunities to prepare for future market environments.



This article is a summary of the article titled, “Silicon Carbide Adoption Enters Next Phase with Focus on Device Reliability, Gate Drive Innovation, and Total System Solutions,” written by Orlando Esparza, Strategic Marketing Manager for Microchip Technology.