High-Voltage Quasi-Vertical GaN Junction Barrier Schottky Diode With Fast Switching Characteristics

In this letter, we report a quasi-vertical GaN junction barrier Schottky diode on low-cost sapphire substrate. With the high quality GaN epitaxy and selective-area p-islands formed via Magnesium ion implantation at the anode region, reverse leakage in level of 10(-7) A/cm(2) was achieved, as well as a high on/off current ratio of 10(10) and a high breakdown voltage of 838 V. Meanwhile, advantageous characteristics as expected in vertical GaN Schottky barrier diode were realized, including a low turn-on voltage of 0.5 V and fast switching performance under 400 V/10 A operation condition. Along with the improved heat dissipation via substrate thinning and packaging techniques, the diode retains a relatively low thermal resistance, enabling high current rectification level over 60 A, power efficiency up to 98.7 %, while maintaining low case temperatures.

Automated summary

A quasi-vertical GaN junction barrier Schottky diode on low-cost sapphire substrate was successfully demonstrated, exhibiting excellent performance attributes such as low reverse leakage, high breakdown voltage, and fast switching capability. Improved heat dissipation techniques enable the diode to achieve high current rectification levels, high power efficiency, and low case temperatures.