Mobility-Modulation Field Effect Transistor Based on Electrospun Aluminum Doped Zinc Oxide Nanowires

• Published in: ECS journal of solid state science and technology 2016-01, Vol.5 (3), p.Q92-Q97
• Main Authors: Belyaev, Maksim, Putrolaynen, Vadim, Velichko, Andrey, Markova, Nadezhda
• Format: Article
• Language: English
• ISSN: 2162-8769; 2162-8769; 2162-8777
• DOI: 10.1149/2.0141603jss

This paper presents the findings of research into field effect transistors (FET) based on aluminum doped zinc oxide (AZO) nanowires that resulted in developing an effective field-effect channal conductivity control method implemented by intensive modulation of charge carriers mobility. AZO (Al ∼ 2% at.) nanowires were fabricated by electrospinning technique, and the obtained nanocrystalline nanowires had diameter of 150 - 200 nm and average grain size of ∼10 nm. FET was assembled using AZO nanowires with back side gate configuration and demonstrated n-type behavior and on-off current ratio up to 103. Using grain boundary (GB) model we have found electron concentration in the FET channel in off-state and on-state to be 1.8·1019 cm−3 and 4.1·1019 cm−3, respectively. Meanwhile, the corresponding effective field-effect mobility changed significantly from 2.5·10−6 cm2/V·s to 3.3·10−3 cm2/V·s. Mobility change (∼103) was attributed to lowering of potential barrier inside GB. Areal trap concentration was estimated as 3·1013 cm−2 and donor concentration as 4.5·1019 cm−3. The results presented open up new opportunities for the developing of a new type of mobility-modulation field-effect transistors.