ZnO Nanowire Transistors

• Published in: The journal of physical chemistry. B Vol. 109; no. 1; pp. 9 - 14
• Main Authors: Goldberger, Josh, Sirbuly, Donald J., Law, Matt, Yang, Peidong
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 13.01.2005
• Subjects: Nanowires - chemistry; Temperature; Time Factors; Transistors, Electronic; Zinc Oxide - chemistry
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp0452599

ZnO nanowire field-effect transistors (FETs) were fabricated and studied in vacuum and a variety of ambient gases from 5 to 300 K. In air, these n-type nanowire transistors have among the highest mobilities yet reported for ZnO FETs (μe = 13 ± 5 cm2 V-1 s-1), with carrier concentrations averaging 5.2 ± 2.5 × 1017 cm-3 and on−off current ratios ranging from 105 to 107. Four probe measurements show that the resistivity of the Ti/Au−ZnO contacts is 0.002−0.02 Ω·cm. The performance characteristics of the nanowire transistors are intimately tied to the presence and nature of adsorbed surface species. In addition, we describe a dynamic gate effect that seems to involve mobile surface charges and causes hysteresis in the transconductance, among other effects.