Development of vertical bulk gallium nitride power devices

Gallium nitride (GaN) is a promising material for power electronics due to its outstanding properties, such as high critical electric field and large bandgap. Despite its superior intrinsic properties, fabrication processes and technology for vertical GaN power electronics is still not as mature as in conventional materials. This thesis covers three aspects of vertical power devices on bulk GaN to increase their reliability and performance. The first is the breakdown behavior of GaN under high electric fields. Vertical Schottky diodes with multi-finger anodes are simulated, fabricated and characterized. Evidence of impact ionization and signs of avalanche breakdown are shown. The second aspect is scalable fabrication technologies for vertical power FinFETs. Key processing stesps are refined and demonstrated on large-area devices. The final topic covered is GaN superjunction (SJ) technology in the context vertical power FinFETs. The SJ FinFET concept is first introduced then an underutilized method for p-type doping GaN is explored as an alternative to conventional p-type regrowth and ion implantation. Finally, the proposed GaN SJ FinFET is investigated with simulations. Various standard SJ parameters are optimized and a novel electric field management technique is proposed.

Name thesis:degree_name

Master

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2019

Author dc:creator

• Muñoz, Ayrton D.

Advisor dc:contributor.advisor

• Tomás Palacios.

• Electrical Engineering and Computer Science.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/124259

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/124259