Influence of passivation, doping and geometrical parameters on the avalanche breakdown of GaN SBDs

[EN]The breakdown of GaN-based Schottky barrier diodes associated with impact-ionization events initiated by electrons injected by tunneling is physically analyzed by means of a Monte Carlo simulator self-consistently coupled with a two-dimensional solution of the Poisson equation. Simulations of a...

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Detalles Bibliográficos
Autores: Orfao, Beatriz, Peña, R. A., García Vasallo, Beatriz, Pérez Santos, María Susana, Mateos López, Javier, González Sánchez, Tomás
Tipo de recurso: artículo
Estado:Versión borrador
Fecha de publicación:2025
País:España
Institución:Universidad de Salamanca (USAL)
Repositorio:GREDOS. Repositorio Institucional de la Universidad de Salamanca
OAI Identifier:oai:gredos.usal.es:10366/169272
Acceso en línea:http://hdl.handle.net/10366/169272
Access Level:acceso abierto
Palabra clave:Schottky barrier diode
Impact ionization
Tunnel current
Breakdown
2203 Electrónica
Descripción
Sumario:[EN]The breakdown of GaN-based Schottky barrier diodes associated with impact-ionization events initiated by electrons injected by tunneling is physically analyzed by means of a Monte Carlo simulator self-consistently coupled with a two-dimensional solution of the Poisson equation. Simulations of a realistic topology where different geometrical parameters are modified allow to identify their influence on the breakdown voltage. The correct physical modelling of two-dimensional effects is essential for a proper prediction of the breakdown. Epilayer doping and thickness, dielectric used for the passivation and lateral extension of the epilayer are analyzed. As expected, the lower the doping and the thicker the epilayer, the higher the value found for the breakdown voltage, but, interestingly, the results also indicate that the peak electric field present at the edge of the Schottky contact, which may be reduced by means of high-k dielectric passivation and a short lateral extension of the epilayer, plays a key role in the breakdown.