Harvesting the potential performance of GaN-based devices in terms of the areal power density and reliability, relies on the efficiency of their thermal management. Integration of extremely high thermal conductivity Single-crystalline CVD-diamond serves as an efficient solution to their strict thermal requirements. However, the major challenge lies in the Thermal Boundary Resistance (TBR) at the interface of GaN/Diamond or SiC/Diamond. Junction temperature of the device shows a sensitivity of 1.28°C for every unit of TBR for GaN-on-Diamond compared to 0.43°C for every 10 units of TBR for GaN/SiC-on-Diamond. Finite Volume Thermal Analysis has shown a limit of around 22 m2K/GW beyond which the merit of proximity to the heat-source for GaN-on-Diamond can no more outperform GaN/SiC-on-Diamond. Besides, due to the temperature dependency of the thermal conductivity K, an increase in the temperature causes an increase in the thermal resistivity of the device which is more significant in high power operations. Simplified assumption of constant K overestimates the device performance by resulting in 17.4°C lower junction temperature for the areal power density of 10W/mm. Other part of the project regarding the in-house growth of CVD-diamond to be bonded to the GaN device has been simultaneously in progress.

中文翻译：

---

使用金刚石散热器对 GaN HEMT 器件进行热建模

在面功率密度和可靠性方面收获基于 GaN 的器件的潜在性能，依赖于它们的热管理效率。极高热导率的集成 单晶 CVD 金刚石是满足其严格热要求的有效解决方案。然而，主要挑战在于 GaN/金刚石或 SiC/金刚石界面处的热边界电阻 (TBR)。该器件的结温显示，对于金刚石基 GaN，每单位 TBR 的灵敏度为 1.28°C，而对于 GaN/SiC-金刚石，每 10 个单位 TBR 的灵敏度为 0.43°C。有限体积热分析显示出大约 22 m2K/GW 的限制，超过该限制后，金刚石基 GaN 接近热源的优势将不再优于 GaN/SiC 金刚石。除了，由于热导率 K 的温度依赖性，温度升高会导致器件热阻增加，这在高功率操作中更为显着。对于 10W/mm 的面功率密度，常数 K 的简化假设会导致结温降低 17.4°C，从而高估了器件性能。与 GaN 器件结合的 CVD 金刚石的内部生长项目的其他部分也在同时进行。