Impact of the low temperature ohmic contact process on DC and forward gate bias stress operation of GaN HEMT devices

Date
2022-08-17
Advisor
Instructor
Source Title
IEEE Electron Device Letters
Print ISSN
0741-3106
Electronic ISSN
1558-0563
Publisher
Institute of Electrical and Electronics Engineers
Volume
43
Issue
10
Pages
1609 - 1612
Language
English
Type
Article
Journal Title
Journal ISSN
Volume Title
Abstract

In AlGaN/GaN high electron mobility transistors (HEMTs), high temperature processes (such as ohmic annealing with >800°C value) could deform the crystal structure and induce trap states within the bulk and surface. Expanded defect densities cause crucial problems, such as threshold voltage ( Vth ) instability, current collapse, and high leakages. In this work, a low temperature ohmic contact process (630°C, 10 minutes) is adopted with recess etch, and contact resistances <0.1Ω ⋅ mm with low sheet resistances are achieved. The positive impact of this low thermal budget process on surface morphology, DC operation, long-term stability, and forward gate bias stress of the device is studied.

Course
Other identifiers
Book Title
Keywords
AlGaN/GaN HEMTs, Ohmic contact, Stabil15 ity, Surface roughness, Annealing temperatures, Recessed 16 ohmic contacts
Citation
Published Version (Please cite this version)