Flip-Chip AlGaN/GaN Schottky Barrier Diode Using Buried-Ohmic Anode Structure With Robust Surge Current Ruggedness and Transient Energy Sustaining Capability

Robust reliability is essential for electronic devices against inductive transient shocks in power switching applications. In this work, rugged surge current tolerance and transient energy sustaining capability are simultaneously demonstrated in AlGaN/GaN Schottky barrier diodes (SBDs) for the first time, which greatly fills the research gap toward the device reliability requirements for inductive switching applications. Such robustness is attributed to the combined advantages of the uniquely designed buried-ohmic anode structure and efficient thermal management enabled by substrate thinning and flipchip packaging techniques. The resultant device exhibits a high surge current density of 3.4 kA/cm(2) (42 A) and a critical transient dissipating energy density of 1.5 J/cm(2) (18.6 mJ). All these values are the highest reported in AIGaN/GaN SBDs. In particular, the superior switching performance with nanosecond reverse recovery time is achieved under a 400-V operating condition with a fast di/dt of 200 mu/ps, implying the desired functionality of the proposed device architecture. This work, thus, makes a significant step in reaching the promise of AlGaN/GaN SBDs for high-reliability and high-power applications.

Automated summary

This work demonstrates, for the first time, the ability of AlGaN/GaN SBDs to withstand both surge current shocks and transient energy, addressing the device reliability requirements for inductive switching applications. The high surge current density and critical transient dissipating energy density achieved in this study, along with superior switching performance, make significant progress towards the promise of AlGaN/GaN SBDs for high-reliability and high-power applications.