Back to Search
Start Over
Contact Resistance and Leakage Current of GaN Devices with Annealed Ti/Al/Mo/Au Ohmic Contacts
- Source :
- JSTS:Journal of Semiconductor Technology and Science. 16:179-184
- Publication Year :
- 2016
- Publisher :
- The Institute of Electronics Engineers of Korea, 2016.
-
Abstract
- In recent years, the on-resistance, power loss and cell density of Si power devices have not exhibited significant improvements, and performance is approaching the material limits. GaN is considered an attractive material for future high-power applications because of the wide band-gap, large breakdown field, high electron mobility, high switching speed and low on-resistance. Here we report on the Ohmic contact resistance and reversebias characteristics of AlGaN/GaN Schottky barrier diodes with and without annealing. Annealing in oxygen at 500℃ resulted in an increase in the breakdown voltage from 641 to 1,172 V for devices with an anode-cathode separation of 20 μm. However, these annealing conditions also resulted in an increase in the contact resistance of 0.183 Ω-mm, which is attributed to oxidation of the metal contacts. Auger electron spectroscopy revealed diffusion of oxygen and Au into the AlGaN and GaN layers following annealing. The improved reverse-bias characteristics following annealing in oxygen are attributed to passivation of dangling bonds and plasma damage due to interactions between oxygen and GaN/AlGaN. Thermal annealing is therefore useful during the fabrication of high-voltage GaN devices, but the effects on the Ohmic contact resistance should be considered.
- Subjects :
- 010302 applied physics
Auger electron spectroscopy
Materials science
Passivation
business.industry
Annealing (metallurgy)
Schottky barrier
Contact resistance
Schottky diode
02 engineering and technology
021001 nanoscience & nanotechnology
01 natural sciences
Electronic, Optical and Magnetic Materials
0103 physical sciences
Optoelectronics
Breakdown voltage
Electrical and Electronic Engineering
0210 nano-technology
business
Ohmic contact
Subjects
Details
- ISSN :
- 15981657
- Volume :
- 16
- Database :
- OpenAIRE
- Journal :
- JSTS:Journal of Semiconductor Technology and Science
- Accession number :
- edsair.doi...........d0e7b299f4432918bf91984df3d1c0ba