Abstract
The thermal stability and measurement temperature dependence of Schottky contact characteristics on n-GaN using a W 2 B 5 /Ti/Au metallization scheme was studied using current-voltage (I-V), scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) measurements. The elemental profile obtained from samples annealed at 350 °C showed some titanium diffusion into the gold layer but little other difference from the as-deposited wafer. Annealing at 700 °C produced significant diffusion of titanium. The Schottky barrier height increased with anneal temperature up to 200 °C, reaching a maximum value of 0.65 eV, but decreased at higher annealing temperatures. The reverse breakdown voltage from diodes fabricated using the W 2 B 5 -based contacts showed a similar dependence. The reverse current magnitude was larger than predicted by thermionic emission alone. The barrier height showed only minor changes with measurement temperature up to 150 °C.
Original language | English |
---|---|
Pages (from-to) | 5814-5819 |
Number of pages | 6 |
Journal | Applied Surface Science |
Volume | 252 |
Issue number | 16 |
DOIs | |
State | Published - Jun 15 2006 |
Externally published | Yes |
Funding
The work at UF is partially supported by AFOSR grant under grant no. F49620-03-1-0370, by the Army Research Office under grant no. DAAD19-01-1-0603, NSF (CTS-0301178, monitored by Dr. M. Burka and Dr. D. Senich) and the National Science Foundation (DMR 0400416, Dr. L. Hess).
Keywords
- Temperature dependence
- Thermal stability
- n-GaN