In recent years, the application of 5G communication technology in mobile terminals has been steadily advancing, resulting in a growing and pressing demand for low-voltage, high-performance radio frequency (RF) power amplifiers (PAs). Gallium nitride (GaN) high electron mobility transistors (HEMTs) stand out as ideal candidates for high-performance RF front-ends, owing to their remarkable attributes, including high electron saturation velocity and outstanding two-dimensional electron gas (2DEG) transport properties. Nevertheless, traditional GaN devices typically exhibit relatively high knee voltages, which constrain their RF output performance under low-voltage conditions. Globally, the prevalent approaches to tackle this challenge involve the utilization of strongly polarized heterojunctions (such as InAlN/GaN, AlN/GaN, etc.) and the adoption of the 'deep scaling' process route. However, these methods necessitate a high degree of processing precision.