Browsing by Author "Wu, Yuan-Chun"

Now showing 1 - 5 of 5

Enhancing Performance in Thin Tilm Transistors with Vacuum or Solution Processed Amorphous Oxide Semiconductors Towards Display Applications
(2018-01-01)
Chen, Changdong
;
Li, Gongtan
;
Li, MinMin
;
Yang, Bo-Ru
;
Liu, Chuan
To simultaneously achieve high mobility and good reliability of thin-film transistors (TFTs), we controlled oxygen vacancies via nitrogen incorporation in InGaZnO TFTs from vacuum-or solution-based methods. For display applications, IGZO and crystalline silicon TFTs were integrated together to build hybrid CMOS. Also, additive patterning method is developed for solution-processed oxide semiconductors, based on which wafer-scale TFT arrays and NMOS have been demonstrated.
Fabrication of pattern-depended metal induced lateral crystallization polysilicon thin film transistors with NH3 plasma passivation effects
(2005)
Chou, Cheng-Wei
;
Wu, Yung-Chun
;
Wu, Yuan-Chun
;
Chang, Ting-Chang
;
Liu, Po-Tsun
A pattern-dependent metal-induced lateral crystallized (PDMILC) poly-Si thin film transistor was successfully demonstrated and characterized. The fabrication of new PDMILC is simple with only four-mask process. After NH3 plasma passivation, the device performance was enhanced, including the high on/off current ration (>10(6)), the high mobilit (31.19 cm(2)/Vs), and the steep subtreshold swing (0.483 V/dec). The performance of PDMLC TFT with NH3 plasma passivation is superior to that of the counterpart without NH3 plasma passivation. The NH3 plasma treatment can result in the effective hydrogen passivation of the grain-boundary dangling bonds, and the nitrogen piile-up at SiO2/poly-Si interface.
Integrating Poly-Silicon and InGaZnO Thin-Film Transistors for CMOS Inverters
(2017-09-01)
Chen, ChangDong
;
Yang, Bo-Ru
;
Liu, Chuan
;
Zhou, Xing-Yu
;
Hsu, Yuan-Jun
The applications of a-InGaZnO thin-film transistors (TFTs) to logic circuits have been limited owing to the intrinsic n-channel operation. In this paper, we demonstrated a hybrid inverter constructed by p-channel low-temperature poly-silicon (LTPS) TFTs and n-channel amorphous-indium-gallium-zinc-oxide (a-IGZO) TFTs. Hydrogenated LTPS TFTs and a-IGZO TFTs have been successfully fabricated on the same panel, followed by a rapid thermal annealing treatment to remove the hydrogens in the a-IGZO TFTs. The resulted hybrid inverter exhibits large noise margin closed to V-DD/2 and a high voltage gain as 68.3. Due to the complementary configurations in the static state, the inverter shows small current and thus consumes low power in hundreds of picowatts. As all the fabrication processes are compatible with conventional techniques, the reported results may open new opportunities in circuit design and applications for oxide TFTs.
Nitrogen-Doped Amorphous InZnSnO Thin Film Transistors With a Tandem Structure for High-Mobility and Reliable Operations
(2016-05)
Li, GongTan
;
Yang, Bo-Ru
;
Liu, Chuan
;
Lee, Chia-Yu
;
Wu, Yuan-Chun
The threshold voltage shift (Delta V-th) in amorphous InZnSnO thin-film transistors (a-IZTO TFTs) during negative gate-bias stress (NGBS) is significantly improved by nitrogen doping. Numerous N-In bonds eliminate donorlike subgap states near the Fermi level, which improve stability during stress but degrade electron mobility. We developed tandem TFTs with an a-IZTO:N layer on top of an a-IZTO layer, in which mobility reaches 31.76 +/- 0.81 cm(2)/Vs and the reliability is improved. Especially, Delta V-th in NGBS is reduced by 80% for pristine a-IZTO devices. This simple but an effective method achieves fast and reliable operation in the a-IZTO TFTs.
Subgap State Engineering Using Nitrogen Incorporation to Improve Reliability of Amorphous InGaZnO Thin-Film Transistors in Various Stressing Conditions
(2016-11)
Li, GongTan
;
Zhan, Runze
;
Yang, Bo-Ru
;
Liu, Chuan
;
Dong, ChengYuan
Instability of amorphous InGaZnO thin-film transistors (a-IGZO TFTs) remains an obstacle for commercialization. Here, we systematically discuss the effect of nitrogen incorporation on a-IGZO TFT stability and developed Ar/O-2/N-2 atmosphere to improve the stability under stressing in different conditions. Based on X-ray photoelectron spectrometer results, it is revealed that the positive gate bias stress (PGBS) stability is significantly improved due to microscopically passivated metal-oxygen bonds. Yet, the negative gate bias and light stress (NBLS) stability is seriously deteriorated with heavily nitrogen incorporation probably due to the bandgap narrowing effect. By optimizing a mixed O-2/N-2 atmosphere, the subgap states are finely tuned to afford optimal performance and stability. The developed IGZO TFTs exhibit mobility (12.67 cm(2)/Vs), small shift of threshold voltage under PGBS (reduced by 64% as compared with the pristine a-IGZO TFTs), and good negative gate bias stability and with NBLS stability as well.