Abstract
This work presents β-Ga2O3 trench Schottky barrier diodes (TSBDs) with double drift layer structures, achieving a 34% lower on-resistance compared to conventional single drift layer structures, without compromising the off-state performance. The TSBDs exhibit a breakdown voltage of ~2.4 kV, after which the devices were observed to crack along the [010] crystallographic direction in β-Ga2O3. The mechanisms behind breakdown-induced cracking were investigated including using nanoindentation, which revealed that the cracking is due to relatively weak chemical bonding along the [010] direction.
V. S. Charan
University of Bristol
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8A.2 – kV-Class β-Ga2O3 Trench Schottky Barrier Diodes: Double Drift Layer Design and Breakdown Analysis
Sai Charan Vanjari, University of BristolA. K. Bhat, University of BristolH. Huang, University of BristolMatthew Smith, University of BristolJ. W. Pomeroy, University of Bristol, Bristol, UKM. Kuball, University of Bristol, Bristol, UK -
8A.3 – Vertical Schottky Barrier Diodes with Optical Floating Zone Growth of β-Ga2O3 Single Crystals and Electrical Defect Study
V. L. Ananthu Vijayan, Anna University, University of BristolV. S. Charan, University of BristolC. A. Dawe, University of BristolV. P. Markevich, The University of ManchesterM. P. Halsall, The University of ManchesterA. R. Peaker, The University of ManchesterS. M. Babu, University of BristolM. Kuball, University of Bristol, Bristol, UKAbstract
This study reports the melt growth of β-Ga2O3 single crystals using the Optical Floating Zone (OFZ) technique, and defect analysis in these wafers. X-ray diffraction (XRD) rocking curves show a full width at half maximum (FWHM) of 230 arcsec and the chemical mechanical polished surfaces exhibit a low surface roughness of 1.1 nm. Schottky barrier diodes (SBDs) were fabricated on these substrates and deep-level transient spectroscopy (DLTS) measurements were performed to investigate defects within the bandgap. DLTS analysis revealed a dominant single deep-level trap at 0.69 eV below the conduction band, attributed to Fe impurities from the source material used for melt-growth. -
8A.4 – Gallium Oxide Trench Schottky Barrier Diodes with Field Plate Edge-Termination
A. K. Bhat, University of BristolV. S. Charan, University of BristolMatthew Smith, University of BristolM. Kuball, University of Bristol, Bristol, UKAbstract
In this work, Gallium Oxide (β-Ga2O3) based trench Schottky barrier diodes (TSBDs) with field plate edge-termination are reported. The SiNx field plate edge-terminated TSBDs show an improvement in breakdown voltage up to 2.3 kV as compared to the unterminated structures of 1 kV. The electric field simulations show a reduction in peak electric field at the edge of the diodes when terminated with SiNx field plates. Reliability measurements were performed by reverse-bias step-stressing and observing the on-state performance post stressing. An increase in on-resistance for TSBDs with field plate edge termination up to 12% is observed when devices are stressed at 1 kV.