I. Introduction
The power devices, which can be easily implemented on the large-scale, high-quality bulk single-crystal substrates [1]–[3], are highly attractive for high-power applications due to its superior material properties such as high critical electric field of 8 MV/cm [4]–[7]. Among the -Ga2O3 power rectifiers, the Schottky barrier diodes (SBDs) can deliver lower conduction/switching losses and higher switching frequency, owing to its lower forward turn-on voltage () and the faster reverse recovery capability [8], [9]. Despite these promises, the weak electrothermal ruggedness of Ga2O3 devices with low thermal conductivity (-0.3 Wcm−1K−K) against surge current transients is still a critical reliability concern [3], [10]–[12]. Under high inrush current conditions, the Ga2O3 SBDs with inferior heat dissipation capability may undergo severe performance degradation and even thermal runaway [11]. To improve the electrothermal ruggedness, an advanced double-side-cooling package strategy has recently been proposed [3], where the generated heat is extracted directly from the Schottky junction to the baseplate [12], delicately circumventing low- Ga2O3 body region. Such effective thermal management relies on the external system packaging. However, for die-level materials/structures or fabrication processes, improving thermal-related performance of Ga2O3 power devices is currently a formidable challenge [13].