Design/System Technology Co-optimization of Gallium Nitride High Electron Mobility Transistors for Next-G 3DIC Heterogeneous Integration of Gallium Nitride and Si CMOS

Abstract

With data rates pushing into the Tbps, there is an urgent need for the use of mmWave and subterahertz RF front ends and transistors. Gallium Nitride (GaN) transistors have continued to push the limits of high-power density, high frequency semiconductor devices. The future of GaN radio frequency (RF) circuit technology is at the intersection of device engineering, advanced packaging, and circuit design. Currently, these are three separate fields with little-to-no communication between them, resulting in critical limitations to today’s technology. These fields need to collaborate, crosspollinate, and intersect in order to modernize and advance innovation for the next generation of RF front ends. To design the most efficient W-G Band devices and systems, we must embrace a design/system-technology co-optimization (DTCO/STCO) approach, that combines innovative GaN transistors with engineered linearity, novel heterogeneous integration with state-of-the-art Silicon (Si) bias and control circuitry, and advanced physics-based modeling. This thesis presents the development of a 3DIC consisting of GaN HEMTs and Si CMOS BEOL, in particular W-band GaN HEMTs, Si CMOS BEOL circuits in Intel16, and advanced packaging of dielets. The full chip continuum is investigated and innovated upon.