Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5369915 | Applied Surface Science | 2006 | 5 Pages |
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 ZrB2/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 Ã 10â3 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 ZrB2. The boride-based contacts exhibit higher thermal stability but poorer specific contact resistivity than conventional Ti/Au metal stacks on ZnO.