Technological devices have completely been transformed with the use of semiconductors, where every device is now powered by a microprocessor or transistor. The first and second-generation semiconductor materials have been the backbone of many devices we use in the last few decades, but the need for semiconductor materials to facilitate high-power applications like renewable energy production, electric vehicles, etc, is becoming increasingly important.
Here’s where third-generation semiconductor materials come into the conversation, providing endless opportunities to the semiconductor industry and the devices and other technological developments that depend on it. There are various third-generation semiconductor types and in this blog post, we will cover the most researched of them along with their applications, advantages, disadvantages, and other details. Stay tuned to learn everything you need to know about third-generation power semiconductors.
The Evolution Of Semiconductors From 1st Generation To 3rd Generation Semiconductors
The first-generation semiconductor materials were Germanium and Silicon, sharing their prime years in the 1950s and 1960s respectively. The second-generation semiconductor materials were Gallium Arsenide (GaAs) and Indium Phosphide (InP) which were developed much later. However, both these generations of semiconductor materials have very prominent disadvantages, making them unable to use in all applications.
The first generation semiconductors like Germanium and silicon devices are unable to support light-emitting electronic devices or high-frequency and high-power devices. On the other hand, the 2nd generational semiconductors were rather difficult to source, costly, and toxic too, making consumer electronics that utilized these semiconductor devices harmful and expensive.
When third-generation semiconductor materials entered the industry, they came with superior physical properties that could facilitate what their predecessors couldn’t. The third-generation semiconductors are called ‘wide energy gap’ or ‘wide bandgap’ semiconductor materials. An energy gap or bandgap denotes the minimum energy required for the semiconductor to switch from insulator to conductor. Unlike its predecessors which are low-energy gap materials, the third-generation semiconductor material has more stable properties that can power highly demanding applications.
What Is A 3rd Generation Semiconductor?
As explained above, third-generation semiconductors have higher energy gaps making energy conversion much more efficient. This means that third-generation semiconductors have stable properties to facilitate high-frequency, high-power efficiency, optoelectronic, high-temperature, and many other highly demanding battery systems or high-energy applications.
There are many types of third-generation semiconductors like Silicon Carbide (SiC), Gallium Nitride (GaN), Zinc Oxide (ZnO), Diamond, and Aluminum Nitride (AlN). However, Gallium Nitride and Silicon Carbide devices are the most popular with their higher power efficiency and many other benefits. We have explored these two forerunners in detail below.
The Most Common 3rd Generation Semiconductors
Silicon Carbide and Gallium Nitride are the two most prominent 3rd generation semiconductors with a number of benefits over first and second-generation semiconductor materials. Below is everything you need to know about GaN and SiC.
#1 Silicon Carbide (SiC)
This semiconductor material is a combination of Silicon and Carbon with strong bonding forces. This makes the semiconductor have high thermal, chemical, and mechanical stability giving it a higher power density to facilitate high-power devices from needing up to 600V to 3.3kV while having a fast switching speed, high electron saturation rate, and more advantages. It is mainly used to power electronics such as diodes and transistors that lay the path to developing a high-power device.
In comparison to silicon materials, Silicon Carbide has four times better thermal performance with a 90% reduction in power losses, making it ideal for devices that must have technology powered on high thermal conductivity, high-voltage levels, and more. It is also small in size. Below are suitable applications for SiC.
Suitable Applications For SiC
SiC can be used to power high-voltage and high-current applications such as offshore wind power, new energy vehicles, smart grids, and other high-frequency applications.
The Future Of SiC
SiC is being used widely for its higher thermal conductivity, energy storage efficiency, etc. However, sourcing the crystals and implementing the core technology behind SiC production is complicated meaning that production at mass is extremely difficult and quite expensive. Its small size also makes it difficult to cut and be utilized.
Research and development are focusing on increasing the wafer sizes of SiC from 6 inches to 8 inches to improve the production cost and frequency and maximize the use of this high-power technology.
#2 Gallium Nitride (GaN)
Gallium Nitride is a binary III/V direct bandgap semiconductor. What this means is that in comparison to SiC, Gallium Nitride’s main advantage is its high frequency due to high electron mobility than SiC. The high breakdown electric field of GaN gives it a higher saturation speed, and higher radiation resistance along with more properties to power electronics requiring up to 600V. This means it can facilitate medium-power devices at the fastest switching speed. Below are the applications it can be used on.
Suitable Applications For GaN
It is suitable for UHF (ultra-high-frequency) applications alongside radio frequency and switching power mode supply applications. This includes 5G communications, power adapters, optical communications due to the semiconductor lighting capabilities, and many more applications.
The Future Of GaN
GaN devices are also relatively difficult to produce especially with their best lattice match which has the highest cost of production. Therefore it works with a GaN-SiC substrate technology with a medium lattice match but at a much better cost. The industry is focusing on improving these production hiccups by focusing on vertical GaN development to power more high-current applications like data centers and electrical vehicles.
The Advantages Of 3rd-Gen Semiconductors
What do the advantages above actually mean in layman’s terms? We’ve explained it in detail below. However, there are many more advantages too.
Higher bandgaps denote a longer time to switch from insulator to conductor, so better properties to power high-current devices.
Higher Saturation Velocity
This denotes the speed at which carriers can carry charge in an electrical field. For 3rd generation semiconductors, this means much higher speed than traditional fast charging, so high frequency is a given.
Increased Thermal Conductivity And High Melting Point
Thermal conductivity is how well the semiconductor can carry out its duty without being affected by the high temperature. SiC has better thermal conductivity than GaN but both third-generation semiconductors perform better than their predecessors. So you won’t see those situations where your mobile phones explode from the heat!
The Disadvantages Of 3rd-Gen Semiconductors
Nothing is perfect, and that is the same for third-generation semiconductors too. Here are some of its most evident disadvantages.
Cannot Replace Its First And Second-Generation Semiconductors
First and second-generation semiconductor materials, that is Silicon and compound semiconductors work together in systems to produce devices that have high reliability and power to power devices adequately. In comparison, 3rd generation semiconductors have a higher technical threshold and not all devices need such high power and speed so you can expect the first two generations to be around for a long time.
Inefficient Manufacturing Process And Cost
The difficulty in sourcing raw materials and implementing key technologies to develop them is expensive, challenging, and time-consuming. This means difficulty in mass production, costly end prices on the final product, and inadequate resources to keep up with the demand. Better approaches are being tested but these semiconductors have not been refined enough to be the sole drivers of the semiconductor industry’s success.
3rd Generation Semiconductors – A High-Power Work in Progress
Third-generation semiconductors have the best stable physical, thermal and chemical properties to power high-energy devices. The high-temperature resistance, high-energy saving capabilities, and excellent technical thresholds make them desirable for the future powered by 5G communications, electrical vehicles, smart power grids, and whatnot. It is a work in progress but the opportunities for the future are endless and will be revolutionary.
The most common semiconductors are Gallium Nitride and Silicon Carbide while Zinc Oxide, Diamond, and Aluminum Nitride are available but used less often.
The high breakdown voltage, high-temperature resistance, high thermal conductivity, high saturation rate, compact size, and higher melting point help them power high-voltage applications while maintaining their own physical properties.