Fully transparent flexible tin-doped zinc oxide thin film transistors fabricated on plastic substrate

Abstract

In this work, we have successfully fabricated bottom gate fully transparent tin-doped zinc oxide thin film transistors (TZO TFTs) fabricated on flexible plastic substrate at low temperature by RF magnetron sputtering. The effect of O2/Ar gas flow ratio during channel deposition on the electrical properties of TZO TFTs was investigated, and we found that the O2/Ar gas flow ratio have a great influence on the electrical properties. TZO TFTs on flexible substrate has very nice electrical characteristics with a low off-state current (Ioff) of 3 pA, a high on/off current ratio of 2 × 107, a high saturation mobility (μsat) of 66.7 cm2/V•s, a steep subthreshold slope (SS) of 333 mV/decade and a threshold voltage (Vth) of 1.2 V. Root-Mean-Square (RMS) roughness of TZO thin film is about 0.52 nm. The transmittance of TZO thin film is about 98%. These results highlight that the excellent device performance can be realized in TZO film and TZO TFT can be a promising candidate for flexible displays.

Oxide-based thin film transistors for flexible electronics

“…Among a large variety of polymer plastics, polyimide (PI) is the most frequently used plastic substrate for flexible oxide-based TFTs [17, . In addition, other polymer plastic foils such as polyethylene naphthalate (PEN) [52,71,[139][140][141][142][143][144][145][146][147][148][149][150][151] , polyethylene-terephthalate (PET) [152][153][154][155][156][157][158][159][160][161][162][163][164] , polycarbonate (PC) [165][166][167] , polyether-sulfone (PES) [168][169][170][171][172] , polydimethylsiloxane (PDMS) [42,173,174] , polyarylate [175] , and poly(vinyl alcohol)(PVA) [176] are also usually used. Glass-fabric reinforced composite films are also fabricated as flexible plastic substrates [177] .…”

Zinc–Tin Oxide Film as an Earth-Abundant Material and Its Versatile Applications to Electronic and Energy Materials

“…Zinc–tin oxide (ZTO) is a wide bandgap semiconductor (Eg = ~3.6 eV) [ 1 , 2 , 3 , 4 ] that has been studied as a potential material for electronic and energy devices, such as thin-film transistors [ 5 , 6 , 7 , 8 ], versatile sensors [ 9 , 10 ], and solar cells [ 11 , 12 , 13 ]. The ZTO film has promising properties, including transparency [ 14 , 15 , 16 ], flexibility [ 14 , 15 ], and semiconducting ability [ 6 ], with high electron charge transport behavior that offers desirable electronic and energy materials. Another merit of the ZTO films is that they have high process compatibility.…”

Research Progress on Flexible Oxide-Based Thin Film Transistors

“…The technological advance in TFTs is a significant factor for promoting the development of such displays [42][43][44][45][46][47][48][49][50]. Researchers around Nomura et al [42], the earliest engaged in this field, have successfully fabricated the first transparent and flexible oxide-based TFTs, which have rapidly attracted the interest of numerous researchers all over the world [51][52][53][54][55][56][57][58][59][60][61]. Compared with hydrogenated amorphous silicon (a-Si:H) TFTs and low-temperature polysilicon (LTPS) TFTs [62][63][64][65][66][67][68][69][70][71][72][73], oxide TFTs are reputed as the next-generation displays TFT technology due to their high performance, such as relatively high carrier mobility, good uniformity, low process temperature, optical transparency, low cost and flexibility [74][75][76][77][78][79].…”