Article

Electrical Characterization of Defects Introduced During Sputter Deposition of Schottky Contacts on n -type Ge

Department of Physics, University of Pretoria, Πρετόρια/Πόλη του Ακρωτηρίου, Gauteng, South Africa
Journal of Electronic Materials (Impact Factor: 1.8). 11/2007; 36(12):1604-1607. DOI: 10.1007/s11664-007-0245-y

ABSTRACT

The authors have investigated by deep level transient spectroscopy the electron traps introduced in n-type Ge during sputter deposition of Au Schottky contacts. They have compared the properties of these defects with those
introduced in the same material during high-energy electron irradiation. They found that sputter deposition introduces several
electrically active defects near the surface of Ge. All these defects have also been observed after high-energy electron irradiation.
However, the main defect introduced by electron irradiation, the V-Sb center, was not observed after sputter deposition. Annealing
at 250°C in Ar removed the defects introduced during sputter deposition.

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