Simulation study for GaN-based hybrid trench MOS barrier Schottky diode with an embedded p-type NiO termination: increased forward current density and enhanced breakdown voltage

Abstract

In this work, a hybrid trench MOS barrier Schottky diode (TMBS) structure is proposed to improve both the forward current density and the breakdown voltage (BV) by using TCAD simulation tools. The hybrid structure means that the conventional TMBS rectifier is combined with a p-NiO/n-GaN diode. This can modulate the lateral energy bands by removing the conduction band barriers for electrons. Thus, the improved current spreading effect and the better conductivity modulation can be obtained, leading to the increased current density. Meanwhile, the embedded p-type NiO layer can also help to reduce the electric field at Schottky contact interface and the edge of anode contact/p-NiO layer interface. Thus, the breakdown voltage can be improved remarkably. Moreover, a detailed optimization strategy for the hybrid TMBS is also analyzed by varying the p-NiO layer thickness (TNiO) and the lengths of the anode electrode that is covered on the p-NiO layer (LA).

GaN-based quasi-vertical Schottky barrier diode hybridized with p-NiO layer to achieve 1.1 kV breakdown voltage and enhance the current spreading effect

“…are reported in Ref. 25. The donor-type and acceptor-type trap energy levels of E C − 0.24 eV and E V + 0.46 eV with the trap concentration of 2 × 10 16 cm −3 and 5 × 10 15 cm −3 , respectively are set on the mesa surface.…”

Simulación, fabricación y caracterización de diodos de barrera Schottky de nitruro de galio para aplicaciones en el rango de sub-terahercios

“…Uno de los parámetros fundamentales que limita la gestión de potencia de estos diodos es el voltaje de ruptura, voltaje en inversa para el cual se produce un aumento brusco de corriente (y normalmente se quema). Al realizar la caracterización de los SBDs, el valor del voltaje de ruptura que se obtiene es generalmente menor que el esperado teóricamente [35,36]. Este hecho se puede estudiar mediante modelos que incluyen los fenómenos físicos que ocurren dentro del dispositivo.…”