垂直氮化镓，华为重磅发布

Core Viewpoint - The article presents a new 1200 V fully-vertical GaN-on-Si trench MOSFET utilizing fluorine implanted termination (FIT), which significantly improves breakdown voltage and device performance compared to traditional structures [2][25]. Group 1: Introduction and Background - GaN and SiC wide bandgap semiconductors have great potential in developing efficient, high-density power systems, with GaN transistors widely used in 100 V to 650 V applications, while SiC transistors dominate in high-voltage applications above 1200 V [4]. - The competition between GaN and SiC in the 650 V to 1200 V market is intense, with SiC's high substrate costs limiting its competitiveness [4][5]. - Advances in low-cost, large-diameter silicon substrates for GaN epitaxy have opened new possibilities for high-performance GaN transistors [4]. Group 2: Device Structure and Performance - The newly developed FIT-MOS structure replaces the traditional mesa-etched termination (MET), effectively isolating discrete devices and alleviating electric field crowding effects [7][25]. - The FIT-MOS achieved a breakdown voltage of 1277 V, significantly higher than the 567 V of MET-MOS, with a threshold voltage of 3.3 V, an ON/OFF ratio of approximately 10^7, and a specific on-resistance of 5.6 mΩ·cm² [7][25]. - The device demonstrates a high conduction current density of 8 kA/cm², indicating its suitability for kV-level power electronic systems [7]. Group 3: Manufacturing Process - The manufacturing process of FIT-MOS involves several steps, including gate trench etching, rapid thermal annealing, and fluorine ion implantation to create the FIT region [12]. - The use of a conductive buffer layer made of AlGaN/AlN allows for a fully vertical current path while avoiding complex substrate engineering [15]. Group 4: Comparative Analysis - The FIT-MOS shows advanced performance metrics compared to previously reported GaN vertical trench MOSFETs on various substrates, achieving a Baliga figure of merit (BFOM) of 291 MW/cm² [24]. - The results indicate that the FIT technology enables GaN-on-Si vertical MOSFETs to reach performance levels comparable to those on GaN substrates, marking a significant step towards cost-effective kV-level power applications [24].