Why Gallium Nitride?
About Gallium Nitride (GaN)
In speed, temperature and power handling, gallium nitride is set to take over as silicon power devices reach their limits. GaN is the technology that will allow us to implement essential future cleantech innovations where efficiency is a key requirement.
The excitement about GaN stems from its unique material and electronic properties. GaN devices offer five key characteristics: high dielectric strength, high operating temperature, high current density, high speed switching and low on-resistance. These characteristics are due to the properties of GaN, which, compared to silicon, offers ten times higher electrical breakdown characteristics, three times the bandgap, and exceptional carrier mobility.
Taking advantage of these properties GaN Systems has successfully developed transistors with an on-resistance lower than attainable with silicon, and even better than a mechanical relay contact. This together with GaN’s inherent negligible charge storage, in turn permits the design of power switching circuits with formerly unheard of efficiencies, small size and very low heat losses. Using a unique proprietary custom island topology the company has enabled the designs to be transfered easily from silicon carbide based wafers to lower cost silicon wafers.
Silicon (Si) technology displaced almost all the earlier low power thermionic and electromechanical devices, but fundamental material limitations have stalled its use in higher power applications. All power electronic systems of the future will take full advantage of wide bandgap devices such as GaN. The advantages include;
- Reduced heat sink requirements
- 80% reduction in system volume and weight
- Lower voltage drop for unipolar devices
- Increased output power
- Improved transient characteristics and switching speed
- Reduced electrical noise from smaller system packages
- Reduced electrical noise due to virtually zero recovery charge