CEO Corner – Alex Lidow Dispels the Myth that GaN Devices Cost More than Silicon
GaN Talk – Alex Lidow, Ph.D.
Aug 03, 2022
Back in 2015 Venture Beat published an article on gallium nitride chips taking over from silicon. In that article I made the assertion that widespread adoption of gallium nitride-based power semiconductors would be possible because GaN FETs would have higher performance AND lower cost than silicon. Yet, there is still a widespread misconception that GaN has not yet reached that milestone…that is a false myth. In this blog post, I will attempt to dispel this myth with the caveat that this discussion is limited to devices rated at less than 400 V, as that is the application focus for EPC’s FET and IC products.
It has been more than 12 years since the first GaN-on-Si power transistors started in volume production, and in many applications, such as lidar and space electronics, adoption has been extremely rapid. But what about other markets such as consumer products, computers, motor drives, and automotive? Even in each of those areas GaN devices have started to appear in volume as the predicted tipping point of better performance AND lower cost is a reality.
The Big Myth: GaN devices cost more than silicon devices
This is the most common misconception about GaN technology. In about 2015, the first GaN-on-Si transistors started appearing that were actually lower in price compared with power MOSFETs with the same on-resistance and voltage ratings. Since then, GaN transistor prices have continued to decline, while at the same time, the technology has improved, and die-shrinks have been achieved.
Figure 1 shows a comparison of prices for EPC’s 100 V eGaN® FETs. This chart shows various on-resistance specifications for GaN devices and their MOSFET counterparts. Although medium volume pricing in February 2022 was used, it can be inferred that the same relationship should track to higher volumes.
At higher voltages, where the relative performance differences and size differential between eGaN FETs and MOSFETs is even greater than at lower voltages, the pricing of GaN devices is even comparatively lower.
The comparable pricing ignores the fact that, at equivalent voltage and on-resistance, eGaN FETs are smaller and much faster than the comparable MOSFETs. The users get much greater performance at a comparable price. Designers can test this out for themselves using our web-based cross reference tool which allows the user to easily compare parametric differences and estimated performance to identify the ideal GaN FET to increase performance and reduce cost. Simply enter a silicon MOSFET part number and find suggested replacements.
Designers of power systems must contend with many constraints including performance, size, cost, and reliability. GaN devices check all the boxes for a superior new product. They have superior performance, are easy to use, extremely small, highly reliable, and very affordable. Perhaps most important of all…they are also widely available with short lead times, thanks to a more efficient supply chain matched to this new-generation power device.