Author:
Cheng I-Chun,Wang Bo-Shiung,Hou Hsin-Hu,Chen Jian-Zhang
Abstract
We study the rf-sputtered MgZnO/ZnO heterostructure material system. Two dimensional electron gases are observed in the defective polycrystalline material system. As the MgZnO thickness increases, the sheet resistance reduces rapidly and then saturates. The enhancement of the interfacial polarization effect becomes stronger, corresponding to a larger amount of resistance reduction, when the Mg content in the MgZnO layer increases. Al-doped MgZnO is then introduced as the modulation doping layer to further raise the carrier density without diminishing the carrier mobility. Finally, rf-sputtered MgZnO/ZnO heterostructure thin film transistors (TFTs) are successfully demonstrated. The threshold voltage, field-effect mobility and on/off current ratio of the Mg0.2Zn0.8O/ZnO heterostructure thin film transistor are -0.55 V, 84.2 cm2V-1s-1, and 2x10^6, respectively. In comparison to the ZnO counterpart (VTH= 0.47V, μFE= 1.5 cm2V-1s-1, ON/OFF = 10^5), the polarization effect truly increases the carrier concentration at the interface and improves the field-effect mobility.
Publisher
The Electrochemical Society
Cited by
25 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献