Analysis of Hump Characteristics in Thin-Film Transistors With ZnO Channels Deposited by Sputtering at Various Oxygen Partial Pressures

作者：Furuta Mamoru^*; Kamada Yudai; Kimura Mutsumi; Hiramatsu Takahiro; Matsuda Tokiyoshi; Furuta Hiroshi; Li Chaoyang; Fujita Shizuo; Hirao Takashi

来源：IEEE Electron Device Letters, 2010, 31(11): 1257-1259.

DOI：10.1109/LED.2010.2068276

• Hump characteristics
• intrinsic defects
• sputtering
• thermal desorption spectroscopy (TDS)
• thin-film transistors (TFTs)
• trap density
• zinc oxide

The electrical properties of thin-film transistors (TFTs) with ZnO channels which were deposited by radio-frequency magnetron sputtering at various oxygen partial pressures [p(O(2))] are investigated. A negative shift of the turn-on voltage with a "hump" was observed, and donorlike traps were generated at intermediate energy levels from the conduction band when the ZnO channel was deposited at p(O(2)) below a critical pressure. Thermal desorption spectroscopy study revealed that the donorlike traps were generated when the ZnO film changed from O- to Zn-rich condition. The Zn-related native defects would be a possible origin of the donorlike traps generated at intermediate energy levels in the ZnO TFTs.

• 出版日期2010-11