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Herein, the electrical and thermal performance of lateral AlGaN/GaN high electron mobility transistors (HEMTs) and metal‐insulator‐semiconductor field effect transistors (MISFETs) fabricated with 11 μm thick GaN buffer layers on 200 mm diameter Qromis Substrate Technology (QST) substrates are investigated. The QST substrate has a polycrystalline core engineered to be coefficient of thermal expansion (CTE)‐matched to GaN to minimize wafer bow and residual stress in the GaN film as a result of epitaxial growth. Raman spectroscopy is used to determine the biaxial residual stress in the GaN buffer of the as‐fabricated devices. Electrical characterization is demonstrated on the HEMTs including DC and pulsed output characteristics, DC transfer characteristics, Hall mobility, carrier concentration, sheet resistance, median transition frequency, and maximum stable gain. Finally, the thermal performance of the AlGaN/GaN MISFET is assessed via thermoreflectance thermal imaging at DC power densities up to 19 W mm−1. The thermal resistance of the MISFET, calculated using the peak temperature rises on the gate electrode for DC power densities <10 W mm−1, is measured to be 15.4 mm K W−1, which is comparable with state‐of‐the‐art GaN‐on‐Si lateral transistors. [ABSTRACT FROM AUTHOR]

Co-integration of the key power stage, namely gate drivers and half-bridge in a single-die solution, is a tremendous and inevitable challenge to realizing GaN power integrated circuits (GaN power ICs). In this letter, a monolithically integrated GaN half-bridge including the drivers were successfully fabricated on 200-mm engineered substrates of Qromis substrate technology (QST®). Deep trench isolation together with the buried oxide of the GaN-on-QST® isolates the high side, low side, and the drivers. While on GaN-on-Si, the back-gating effect more and more impedes the integration of a half-bridge’s low side and high side as the voltage increases. This effect is fully eliminated using the proposed effective isolation strategy. In this letter, we will present a single-die GaN power IC exhibiting 200-V swift switching capability. Finally, based on this GaN power IC, a 48V-to-1V single-stage buck converter was successfully demonstrated. [ABSTRACT FROM AUTHOR]