Correlation of microstructure with electrical behavior of Ti/GaN Schottky contacts
- Lawrence Berkeley National Lab., CA (United States)
The authors correlate structural and electrical characteristics of as-deposited and low-temperature annealed Ti contacts on GaN. Temperature dependent current-voltage measurements are used to determine the effective barrier heights of the respective contacts, while high-resolution transmission electron microscopy is utilized for structural characterization. As-deposited Ti contacts are slightly rectifying with an effective barrier height of {approximately}200 meV. After annealing at 230 C, the barrier height increases to values of {approximately}450 meV. A similar behavior of Schottky contacts with more strongly rectifying diodes upon low-temperature annealing is observed for Zr metal contacts on GaN. As-deposited Ti already forms a thin TiN layer at the GaN interface. After annealing at 230 C, the average thickness and the distribution of TiN grains remain practically unchanged, but the interface with GaN roughens. The authors correlate the observed barrier height changes with interface roughness and phase formation and they discuss the results in terms of interface damage and the Schottky-Mott theory.
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 289467
- Journal Information:
- Journal of Electronic Materials, Vol. 27, Issue 11; Other Information: PBD: Nov 1998
- Country of Publication:
- United States
- Language:
- English
Similar Records
Thermally stable Schottky contacts on n-type GaN using ZrB{sub 2}
Structural, microstructural, and electrical properties of gold films and Schottky contacts on remote plasma-cleaned, n-type ZnO{l_brace}0001{r_brace} surfaces