부산대학교 도서관

Graphitic (sp 2 -rich) carbon Schottky contacts to ( $\overline {2}01$ ) $\beta $ -Ga 2 O 3 were fabricated using sputtering and energetic ion deposition with and without the use of an oxygen plasma. As-deposited contacts exhibited room temperature effective barrier heights between 0.80 and 1.20 eV, depending on the deposition technique. After moderate heat treatment (595 K in N 2 ) the work function of the oxygenated graphitic contacts increased by 0.5–0.8 eV. This resulted in a permanent increase in barrier height (up to 1.6 eV) and a corresponding 3–4 orders of magnitude increase in current rectification (at ±3 V). The barrier heights of the heat-treated oxygenated graphitic Schottky contacts agree well with the Mott–Schottky model, suggesting an absence of Fermi level pinning at the C/ $\beta $ -Ga 2 O 3 interface.