0.58 mΩ⋅cm²/523 V GaN Vertical Schottky Barrier Diode With 15.6 kA/cm² Surge Current Enabled by Laser Lift-Off/ Annealing and N-Ion Implantation

Achieving high-performance fully-vertical GaN devices on low-cost and large-scale foreign substrates are highly attractive for the development of device technology. In this work, by performing pulsed laser lift-off and laser annealing techniques, high-performance fully-vertical GaN Schottky barrier diodes (SBDs) with superior N-face ohmic contact characteristics are demonstrated. The resulting device exhibits low specific contact resistivity of
$3.51\times 10^{-{5}}\,\,\Omega \cdot $
cm2 and differential specific on-resistance of 0.58
$\text{m}\Omega \cdot $
cm2, as well as intact anode Schottky contact. In particular, this device demonstrates robust electrothermal robustness, such as the largest surge current density of 15.6 kA/cm2 to date. Moreover, by implementing N-implanted termination, the breakdown voltage of the device is remarkably enhanced from 240 to 523 V, which is competitive with the state-of-the-art quasi-vertical SBDs. These results reveal the notable potential of pulsed laser lift-off/annealing combined with N-implanted termination for realizing fully-vertical devices.