Despite the growing excitement around gallium nitride (GaN), silicon (Si) continues to hold strong in many power module applications, including supporting data centers dealing specifically with high-compute AI workloads.
While GaN offers compelling benefits in switching speed and efficiency, the decision to re-engineer a power module should be based on real system-level value – not just the appeal of new technology.
In fact, some power modules already achieve better than 97% efficiency using silicon, making them highly competitive with GaN.
Why Silicon still holds up
1. Mature and reliable
Firstly, silicon is the dominant technology and offers all the benefits of maturity and ecosystem stability: including many years of optimization, design tools, and reliability data.
Silicon has decades of development behind it. That means better modeling tools, extensive reliability data, well-understood thermal behavior, and a wide range of qualified suppliers. Engineers trust silicon-based components and already have established workflows, test benches, and layout strategies around them.
Another key advantage is silicon’s proven reliability: silicon-based power modules are already qualified in mission-critical, high-reliability applications.
2. Advanced technology
Silicon device vendors continue to improve efficiency: recent generations of superjunction MOSFETs and trench structures rival GaN in many scenarios. Advanced superjunction designs have narrowed the efficiency gap with GaN at many voltage levels (especially for applications below 60V).
In terms of thermal performance and packaging: double-sided cooling and advanced packaging make today’s silicon modules more competitive. Better packaging – including dual-sided cooling, top-side cooling, and low-inductance packaging – has helped silicon-based modules manage thermal resistance more effectively. Combined with improved thermal interfaces in power modules, silicon devices can now push more power within the same form factor.
3. Lower cost and easier integration
Silicon remains more affordable and compatible with existing systems. For many applications, cost is still king. Silicon benefits from mass production and mature fabs that keep costs predictable and supply chains stable.
GaN can still carry a cost premium both for the device itself, and the necessary redesign or qualification effort to add GaN to a system.