The Advantages of Silicon Carbide (SiC) in Power Electronics

Silicon carbide material. Image source: Henan Superior Abrasive

If you are in the field of electronics, especially power electronics, you might have heard something about silicon carbide. You may be considering using silicon carbide in your power electronics application. But, before you do so, it is important to know the ins and outs of this element. What is it, and what are the benefits of using silicon carbide? Well, we have the answers to these questions. In this guide, we will majorly focus on the advantages of silicon carbide in power electronics. Read on to learn some essential properties of silicon carbide that you should know about silicon carbide concerning power electronics.

 Basics of silicon carbide and power electronics

Silicon carbide is a semiconductor element that comprises Silicon (Si) and Carbon (C). These two elements belong to the wide bandgap group of materials. They are known for having strong covalent bonds. This means that they have excellent physical and even mechanical strength. The chemical properties that are a result of the combination of these materials guarantee high levels of stability.

On the other hand, power electronics is a branch of electric engineering that specializes in managing and processing high electric currents and voltages. Proper power management ensures that devices, appliances, and applications can utilize the necessary current and voltage. They should be able to perform to the optimum levels.

 Power electronics also play a protective role.  It ensures that devices and electronic components are well-protected from the effects of overcurrent and overvoltage.

To achieve the desired results in power electronics, engineers thought it was wise to embrace silicon carbide in power electronics. Here, silicon carbide is used for making different electronic components widely featured in power electronics.

Benefits of Silicon Carbide in Power Electronics

Here are some of the key advantages of silicon carbide in power electronics:

High thermal conductivity

Heat is one of the most outstanding features in power electronics. Since power electronics entail high current and voltage, such applications are expected to generate a significant amount of heat. This is where the importance of thermal management comes in.

Silicon carbide has a high thermal conductivity. This is the rate and ease at which an object absorbs heat. Materials with high thermal conductivity are ideal for heat-sensitive applications such as power electronics. Since silicon carbide has a high thermal conductivity, it is ideal for facilitating heat dissipation from sections of an application, system, or even device.

With proper heat management, you should expect optimum performance of power electronics. This is in addition to the reliability of an application. There will be minimum cases of overheating which can lead to serious damages.

Stability of temperature

Closely related to the thermal conductivity is thermal stability.  Silicon carbide is ideal for power electronic applications because it has high-temperature stability. This means that will remain stable despite the changes in temperatures. The physical, chemical, and mechanical properties of silicon carbide will remain the same despite the changes.

So, how is this relevant in power electronics? First, it means that silicon carbide will deliver excellent performance under harsh conditions such as extreme cold or extremely hot. Silicon carbide will operate normally when used on devices such as sensors in power electronics.

Low thermal expansion

Still on matters of heat, low thermal expansion is another key advantage why silicon carbide is  [referred material for the power electronic components. Low thermal expansion, means that the size and structure of the material will not change drastically due to a temperature rise. High thermal expansion means that the material will expand more when exposed to high temperatures. The coefficient ratio of thermal expansion gives a ratio of how much of the material will expand per 2 degrees Celsius rise in temperature.  This ratio is very low for the silicon carbide.

This has a positive impact on any power electronics application as it means that there will be minimal physical damage on various parts of an application. It means that the parts will suffer less fatigue and stress caused by the constant temperature changes in an application.

Low power and switching losses

Silicon carbide tends to have low power and switching losses. This simply means that there will be minimal energy loss when the state of an electric circuit changes from On to Off. This is among the most desirable features of most semiconductor electronic components such as transistors and diodes. They rely on this feature to perform well.

Usually, when a device changes its state from conducting electric current (on) to non-conducting (off), or vice-versa, there will be some level of energy loss that will be experienced during this change of state. Several factors can be blamed for this. High energy loss is likely to affect the energy efficiency of a device.

For silicon carbide, the energy loss during the switching process is very low. This ends up boosting the overall energy efficiency of a power electronics system.

High physical and structural strength

 When it comes to its physical properties, Silicon carbide is one of the hardest materials that are used in electronic applications. It is physically and structurally hard.  Compared to most of its alternatives, silicon carbide tends to perform way better in terms of structural strength.

What are the benefits of hardness in power electronics? First, it means that the material is best suited to be used in applications that are characterized by constant physical activities such as cutting and grinding. It will still serve well without getting damaged. Hardness is also a desirable feature when you are keen on the reliability of a product. The silicon carbide material will serve you for extended periods.  You will worry less about the maintenance costs that are associated with silicon carbide components. In other words, silicon carbide components tend to have a longer lifetime than most alternative materials.

Chemical inert

In the world of chemistry, a material is chemically inert when does not react easily when exposed to chemicals. One of the reasons why silicon carbide is used in power electronic applications is due to its chemical inertness. It rarely reacts negatively when exposed to different chemical conditions.

Since we know that power electronics are used in a  wide range of applications, it is expected that the components will be exposed to different chemical environments. Some application areas feature the use of chemicals.  A perfect example is a chemical processing plant. In other applications, the environment may be laden with chemical elements. It will make sense to use materials that are rarely affected by these chemicals. This is where silicon carbide comes in.

Small die size with better performance

Size is also an important reason as to why silicon carbide material is widely accepted in power electronic applications. This material has a small die size yet is still able to deliver the same breakdown voltage. A small die size makes it possible to pack several transistors into a small area. A direct impact of doing this is high performance, a very desirable property of power electronics. Several transistors packed in a small area increase the processing power of a device.

Small de size had a direct effect on the power consumption of a device. It lowers the consumption rate by a significant margin, It also tends to reduce the generation of heat by the device. All these have a direct impact on power electronics. Energy efficiency and thermal management are among the top two advantages. On the physical aspects, small die size makes it easy to integrate electronic components into a device.

High radiation  resistance

Power electronics entails getting power from various energy sources. Nuclear energy is one of these sources. With nuclear, you will always be concerned by the impact of radiation on the components. Extended exposure to high levels of nuclear radiation can have physical and chemical damage to the components. This will end up inhibiting their performance.

Silicon carbide material is quite different. It has a high resistance to nuclear radiation. The chemical, physical, and structural properties of a silicon carbide material will remain the same. This makes it suitable for use in power electronic applications that have nuclear reactors.

Wide-bandgap

Silicon carbide is a wide-band gap semiconductor. This means that it has a larger band gap than most semiconductor materials that are technically used for the same purpose. One advantage of wide-bandgap is it allows a material to operate at a higher voltage range than most silicon materials. This property improves the energy efficiency of SiC components. It makes such components suitable in applications where the energy that is generated by a system needs to be conserved and used properly. Such applications include renewable energy and electric vehicles.

Why is SiC better than Si in power electronics

Silicon is one of the most commonly used materials in electronic components. While it has dominated this field for many years, silicon carbide is slowly proving to be a better option.

Why is this so?   In as much as silicon seems to be a perfect material, it has some limitations, especially when used in power electronic applications.

One key feature of these applications is the energy gap, which is also known as the bandgap. In power electronics, the gap seems to be wide or high.

Silicon carbide has a higher energy gap than the silicon material. This is one of the reasons why it seems to be an ideal alternative to the latter.

All other key properties of silicon carbide make it a better option than silicon. For instance, it has higher operating temperatures, higher operating voltages, and higher operating frequencies.

In terms of the figures, the energy gap for silicon is 1.12eV while that of silicon carbide is 3.26eV. As you can see, it is three times higher than that of the normal silicon.

Why is silicon carbide capable for high-voltage applications?

As we have mentioned, one of the advantages of SiC is its capacity to handle high voltage. This is possible because they tend to have an extremely high dielectric breakdown intensity. It is higher than that of the ordinary silicon materials. The breakdown voltage of SiC ranges between 600V to several thousand. Comparatively, it is 10 times higher than that of silicon material.

Given that the operating voltage of most power electronic applications is quite high, it makes sense to use SiC as the go-to material for electronic components. This helps to preserve the performance, efficiency, and reliability of a system.

Conclusion

Are you building a powerful electronic device or application?  You should consider embracing electronic components that are made of silicon carbide. They promise to deliver the desired results and have a high reliability rating.

While energy efficiency and thermal management are the top two advantages of SiC, there are many other benefits of silicon carbide in power electronics. Manufacturers of different electronic devices have an easy time designing and building a powerful electronic system that will have all the features to deliver the best performance.

How do I ensure that the electronic components that I am buying are made of silicon carbide? It all starts at the point of buying the electronic components. You should be keen enough to ensure that they are made of these two elements.  Unless you are an expert in matters of electronics, it will be hard to know that a component has silicon carbide. Perhaps hiring an expert will help you find the right component that is made of silicon carbide.

Well, there is a better way of doing things- buying from a reputable electronic component distributor. A good and reputable distributor will sell genuine electronic components that have silicon carbide. Rantle East Electronic is one such distributor. We are a global distributor of electronic components for power electronics. Whether you want passive or even electromechanical components, we will provide them, for you. Concerning silicon carbide, we have inspectors and testers whose core task is to verify the materials in an electronic component.  They use advanced and sophisticated systems to verify the presence of these elements. You should contact us directly in case you want genuine components for power electronics.