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A novel diagonal square array junction barrier Schottky (JBS) diode is created to enhance the forward current and reverse breakdown voltage by increasing the Schottky contact area and shortening the diagonal spacing between two adjacent p+ islands in the active area of a JBS diode. The shape of the p+ islands is square and the positional arrangement of the p+ islands is a diagonal array. Half of the upper and lower p+ islands with smaller areas are connected with the innermost p+ guard ring to create more Schottky contact area and laterally extend the electric field to the edge termination. Results show that the forward current density and reverse breakdown voltage for the diagonal square array JBS diode are 4.2% and 10.7% higher than those for the conventional square array JBS diode, respectively. As the spacing increases, the breakdown voltage for the diagonal square array JBS diode and the conventional square array JBS diode decrease by 3.5% and 7.3%, respectively, indicating that the diagonal square array JBS has more uniform depletion regions and electric field to retain the breakdown voltage. [ABSTRACT FROM AUTHOR]

The correlation between barrier inhomogeneities of 4H-SiC Schottky barrier diodes (SBDs) and surface defects and traps for SBDs fabricated with and without chemical–mechanical polishing (CMP) is investigated. 60% of the barrier inhomogeneities of SBDs with invisible surface defects are eliminated when CMP is applied in the refabrication. About 40% of SBDs with carrots inside the active areas exhibit double barriers without using CMP. This excludes that carrots are a cause of barrier inhomogeneities. However, none of the barrier inhomogeneities of the SBDs with carrots can be eliminated by using CMP. Most barrier inhomogeneities of SBDs with various surface defects inside the active areas can be improved by CMP. The difference between the high and low barrier heights of an SBD with CMP was reduced to about 0.02–0.06 eV. Therefore, the leakage current induced by barrier inhomogeneities is also reduced by CMP. Moreover, SBDs with a resistive termination extension (RTE) have a higher barrier height than SBDs without RTE, and there is no direct evidence to show that the inclusion of RTE can induce barrier inhomogeneities. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]