Low Turn-on voltage dual metal AlGaN/GaN Schottky barrier diode

• The Schottky metal for the anode is composed of Ni and Ti for the dual metal SBD.
• Compare to the Ni-SBD, the turn voltage is reduced from 1.47 V to 0.57 V.
• The current density is about 2.2 times larger than for the Ni-SBD at 2 V.
• The breakdown voltage is almost the same as the Ni-SBD.
• A good trade-off between device forward and reverse characteristics.

AlGaN/GaN dual metal Schottky barrier diodes (SBD) are demonstrated on a silicon substrate. The anode is composed of two metals with different work functions to achieve a better trade-off between the forward and the reverse characteristics. The low work function metal Ti reduces the turn-on voltage and the high work function metal Ni at the edge of the anode reduces the reverse leakage current and maintains the breakdown voltage. The turn-on voltage of the Ni-SBD is reduced from 1.47 V to 0.57 V by employing the dual metal anode, and the breakdown voltages are virtually unaffected.