High performance solution-deposited amorphous indium gallium zinc oxide thin film transistors by oxygen plasma treatment

Abstract

Solution-deposited amorphous indium gallium zinc oxide (a-IGZO) thin film transistors (TFTs) with high performance were fabricated using O2-plasma treatment of the films prior to high temperature annealing. The O2-plasma treatment resulted in a decrease in oxygen vacancy and residual hydrocarbon concentration in the a-IGZO films, as well as an improvement in the dielectric/channel interfacial roughness. As a result, the TFTs with O2-plasma treated a-IGZO channel layers showed three times higher linear field-effect mobility compared to the untreated a-IGZO over a range of processing temperatures. The O2-plasma treatment effectively reduces the required processing temperature of solution-deposited a-IGZO films to achieve the required performance.

High performance In2O3 thin film transistors using chemically derived aluminum oxide dielectric

“…The values of sub-threshold swing (SS ¼ @V DS / @log 10 I DS ) were found to be 0.271 V dec À1 , 0.137 V dec À1 , and 0.951 V dec À1 for the TFTs fabricated on AlO x -250 C, AlO x -350 C, and AlO x -500 C, respectively. The high value of "SS" in case of the TFTs made on AlO x -500 C, further confirms the increased carrier concentration in In 2 O 3 deposited on AlOx-500 C. Thus, the inferior performance in case of the In 2 O 3 TFT fabricated using AlOx-500 C as the gate dielectric can be attributed to the scattering of carriers 18 due to the high carrier concentration in the corresponding In 2 O 3 semiconductor layer. Hence, we find that the presence of Al-OH groups in low temperature annealed AlO x film plays a crucial role in In 2 O 3 TFT performance.…”

“…6,7 Solution deposition techniques have also been employed for the fabrication of oxide TFTs. During the last few years, zinc oxide, 8,9 indium oxide, 10,11 zinc tin oxide, 12,13 indium zinc oxide, 14,15 and indium gallium zinc oxide [16][17][18] based thin film transistors with reasonable performance have been reported using spin coating technique. It is noted that, in most of the previously reports on solution processed TFTs, high annealing temperatures have been used to achieve better device performances and the TFTs are operated in very high operating voltage ranges.…”

Impact of UV/O3 treatment on solution-processed amorphous InGaZnO4 thin-film transistors

“…Several papers have reported similar treatments such as UV or plasma for gel films. 21,22 However, they have not been adopted to gel films in the composition region of amorphous InGaZnO 4 . We adopted UV/O 3 treatment to the solution-processed In-Ga-Zn-O gel films and obtained high TFT performance composed of amorphous InGaZnO 4 .…”

Investigation of Low Temperature Process of Solution Processed Oxide Semiconductor as a Thin Film Transistor

“…The a-IGZO TFT showed higher performance in spite of the short annealing time of 5 min compared with annealing in an electric oven for 120 min. Some researchers also reported fabricating IGZO TFTs prepared with the precursor at low temperature using the photo irradiation method [6,7]. In this case, the total process time was reduced compared with that using the thermal annealing process only.…”