Exploring GaN HEMTs for Cutting-Edge Wireless Technologies

Gallium nitride high electron mobility transistors (GaN HEMTs) offer a compelling combination of high-frequency operation, power handling capability, and energy efficiency making them a preferred choice for a wide range of RF and millimeter wave applications where circuit performance, size, and power efficiency are critical factors. One key application area is power amplifiers for 5G and 6G wireless communications where GaN HEMTs can make a crucial difference in reducing the form factor and power consumption. However, HEMT design requirements strongly differ across wireless frequency bands. For instance, the design can be orientated towards sub-20 GHz operation at higher power, or it can be for ³28 GHz operation at relatively lower power per device. Meeting a wide range of application requirements demands a co-optimized device architecture and material stack, particularly when targeting emerging technologies such as GaN-on-Si, GaN-on-engineered substrates.

At imec we are developing GaN HEMTs on Si and other engineered substrates which can rival their GaN-on-SiC counterparts in terms of performance, reliability, and sustainability.

This PhD will focus on designing and validating GaN-on-Si HEMTs with enhanced gain, linearity, and reliability, pushing the performance envelope to meet next-gen 5G/6G power amplifier specifications.  As a PhD researcher you will work on:

• HEMT design for improved power and linearity performance through channel and source-drain engineering;
• Develop guidelines for balanced performance-reliability oriented device design through physics-based predictive modeling of HEMT characteristics;
• Build expertise in characterization techniques (e.g. time and frequency domain), aimed at DTCO-driven development of GaN HEMT technology