Mobility Enhancement in RF-Sputtered MgZnO/ZnO Heterostructure Thin-Film Transistors
Journal
IEEE Transactions on Electron Devices
Journal Volume
63
Journal Issue
4
Pages
1545-1549
Date Issued
2016
Author(s)
Abstract
Coplanar top-gate MgZnO/ZnO heterostructure thin-film transistors (TFTs) are fabricated on glass substrates using a large-area processing compatible RF-sputtering technique. The field-effect mobility increases with the Mg content in the MgZnO capping layer. The threshold voltage, saturation field-effect mobility, and ON/OFF current ratio of an Mg 0.2 Zn 0.8 O/ZnO heterostructure TFT are -0.55 V, 84.22 cm 2 V -1 s -1 , and 3 �� 10 6 , respectively. In comparison with a ZnO TFT, the mobility is enhanced by a factor of >50. Inverters based on Mg 0.2 Zn 0.8 O/ZnO TFTs are then demonstrated by connecting load transistors operated at VGS = VDD (supply voltage) to drive transistors. A peak gain magnitude of 19.6 is obtained in the Mg 0.2 Zn 0.8 O/ZnO inverter with a geometric aspect ratio of 15 at VDD of 18 V.
Type
journal article