Exploiting the Unique Properties of GaN for Next Wave of Mobile Communications
Combining a high sheet charge, high electron mobility and wide bandgap, GaN devices have gained a lot of interest in recent years, not only for high-voltage power electronics but also for high frequency applications as these devices might provide the speed, output power (Pout) and power added efficiency (PAE) required for the RF Front-End Modules (RF-FEM) targeting next generation wireless communication. This is especially important at mm-wave frequencies, where beamforming radio architectures will require the use of phased antenna arrays and where the different antennas in an array are each driven by a power amplifier. Providing a higher Pout and PAE means a lower number of elements will be needed to drive the antennas and more energy-efficient systems at smaller form factor can be enabled, which is essential for handheld devices and small cells limited in area. In that context, GaN and III-V devices have a clear advantage over Si CMOS and SiGe HBT, but their lower integration potential, still restricted to smaller size substrates and lab-like processing today, is one of the key concerns for adopting those technologies for 5G mm-wave applications. Upscaling those devices to a 200mm and even 300mm Si platform will be a first step to enable a fully integrated heterogeneous system that can tackle the challenges of next generation wireless communication.