Electro-Thermal Analysis and Edge Termination Techniques of High Current β-Ga2 O3 Schottky Rectifiers

Abstract

The performance and limitations of β-Ga2 O3 Schottky rectifiers is studied via simulation using the Florida Object Oriented Device and Process (FLOODS) TCAD simulator. The effect of forward bias and power is examined for various bulk and epitaxial layer thicknesses as well as for heat sink geometries. Thicker bulk/substrate results in higher maximum temperature values whereas a thinner epitaxial-layer results in higher forward currents and hence a higher maximum temperature values via Joule heating. A Cu finned heat sink geometry results in a 26.76% reduction in the maximum temperature. Edge termination techniques are examined for β-Ga2 O3 Schottky rectifiers in order to maximize the breakdown voltage, identify the location of breakdown and mitigate the maximum electric field. Best results have been observed for A1203 as the dielectric material in a field-plate structure while the effect of field-plate dimensions is also studied.