Abstract
There is a strong interest in developing thermally stable metallization schemes for ZnO and boride-based contact stacks are expected to have potential because of their thermodynamic stability. The contact characteristics on bulk single-crystal n-ZnO of a ZrB 2 /Pt/Au metallization scheme deposited by sputtering are reported as a function of annealing temperature in the range 300-800°C. The contacts were rectifying for anneal temperatures <500 °C but exhibited Ohmic behavior at higher temperatures and exhibit a minimum specific contact resistivity of 9 × 10 -3 Ω cm after 700 °C anneals. The contact stack reverts to rectifying behavior after annealing above 800 °C, coincident with a degraded surface morphology and intermixing of the Au, Pt and ZrB 2 . The boride-based contacts exhibit higher thermal stability but poorer specific contact resistivity than conventional Ti/Au metal stacks on ZnO.
Original language | English |
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Pages (from-to) | 2465-2469 |
Number of pages | 5 |
Journal | Applied Surface Science |
Volume | 253 |
Issue number | 5 |
DOIs | |
State | Published - Dec 30 2006 |
Externally published | Yes |
Funding
This research was sponsored by ARO under grant no. DAAD19-01-1-0603, the Army Research Laboratory, NSF DMR 0400416, 0305228, Dr. L. Hess), DOE grant DE-FC26-04NT42271), and AFOSR under grant F49620-03-1-0370 and by DOE contract DE-AC05-00OR22725. The authors acknowledge the Major Analytical Instrumentation Center, Department of Materials Science and Engineering, University of Florida.
Keywords
- Borides
- Contacts
- ZnO