Jae Kyeong Jeong 교수

We investigated the impact of the passivation layer on the stability of indium-gallium-zinc oxide (IGZO) thin film transistors. While the device without any passivation layer showed a huge threshold voltage (Vth) shift under positive gate voltage stress, the suitably passivated device did not exhibit any Vth shift. The charge trapping model, which has been believed to be a plausible mechanism, cannot by itself explain this behavior. Instead, the Vth instability was attributed to the interaction

The authors report the fabrication of high performance thin film transistors (TFTs) with an amorphous indium gallium zinc oxide (a-IGZO) channel, which was deposited by cosputtering using a dual IGZO and indium zinc oxide (IZO) target. The effect of the indium content on the device performance of the a-IGZO TFTs was investigated. At a relatively low IZO power of 400W, the field-effect mobility (μFE) and subthreshold gate swing (S) of the a-IGZO TFTs were dramatically improved to 19.3cm2∕Vs and 0

The purpose of this paper is to give an overview of the state-of-the-art of metal oxide thin-film transistors (TFTs). First, the question of how to achieve high-performance oxide TFTs is addressed, including the exploration of new channel materials, the realization of low-resistance ohmic contacts and the implementation of high-k dielectric materials as the gate insulator. The electrical instability of the oxide TFTs is also discussed, which is critical for their application in flexible backplan

Novel ZrInZnO semiconductor materials to resolve transistor instability for active-matrix organic light-emitting diodes are proposed. The ZrInZnO film is preprared using a cosputtering method, and presents a nanocrystal structure embedded in an amorphous matrix. The thin-film transistors fabricated have good electrical performances as well as excellent stability under long-term bias stresses.

This review gives an overview of the recent progress in vacuum-based n-type transition metal oxide (TMO) thin film transistors (TFTs). Several excellent review papers regarding metal oxide TFTs in terms of fundamental electron structure, device process and reliability have been published. In particular, the required field-effect mobility of TMO TFTs has been increasing rapidly to meet the demands of the ultra-high-resolution, large panel size and three dimensional visual effects as a megatrend o

Abstract The full color 12.1‐inch WXGA active‐matrix organic light emitting diode (AMOLED) display was, for the first time, demonstrated using indium‐gallium‐zinc oxide (IGZO) thin‐film transistors (TFTs) as an active‐matrix back plane. It was found that the fabricated AMOLED display did not suffer from the well‐known pixel non‐uniformity of luminance, even though the simple structure consisting of 2 transistors and 1 capacitor was adopted as a unit pixel circuit, which was attributed to the amo

Ultrahigh-resolution displays for augmented reality (AR) and virtual reality (VR) applications require a novel architecture and process. Atomic-layer deposition (ALD) enables the facile fabrication of indium-gallium zinc oxide (IGZO) thin-film transistors (TFTs) on a substrate with a nonplanar surface due to its excellent step coverage and accurate thickness control. Here, we report all-ALD-derived TFTs using IGZO and HfO₂ as the channel layer and gate insulator, respectively. A bilay

Zinc‐based metal oxide semiconductors have attracted attention as an alternative to current silicon‐based semiconductors for applications in transparent and flexible electronics. Despite this, metal oxide transistors require significant improvements in performance and electrical reliability before they can be applied widely in optoelectronics. Amorphous indium–zinc–tin oxide (a‐IZTO) has been considered an alternative channel layer to a prototypical indium–gallium–zinc oxide (IGZO) with the aim

The effect of gallium (Ga) concentration on the structural evolution of atomic-layer-deposited indium gallium oxide (IGO) (In_1-<i>x</i>Ga<i>_x</i>O) films as high-mobility n-channel semiconducting layers was investigated. Different Ga concentrations in 10-13 nm thick In_1-<i>x</i>Ga<i>_x</i>O films allowed versatile phase structures to be amorphous, highly ordered, and randomly oriented crystalline by thermal annealing at either 400 or 700 °C for 1 h. Hea

This paper reports the effect of the cation composition on the electrical properties of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) where atomic layer deposition (ALD) was used to deposit an a-IGZO channel layer. The In0.38Ga0.18Zn0.44O transistors at a 200°C annealing temperature exhibited 39.4 cm2/V·s field effect mobility (µFE), −0.12 V threshold voltage (VTH), 0.40 V/decade subthreshold gate swing (SS), and >107 ION/OFF ratio, corresponding to the state-of-the-a

Highly improved negative bias illumination stress stability was achieved in a Zn–Sn–O field effect transistor after an ozone (O3) treatment. The untreated ZTO FET exhibited a huge negative threshold voltage shift of 4.2 V but the O3 treated device exhibited superior stability under NBIS conditions: the Vth value of the O3 treated ZTO FET for 600 s showed almost no change (ΔVth = −0.07 V) under the same NBIS. The improvement in NBIS stability of the O3 treated ZTO FETs was attributed to the lower

This study examined the effects of hydrogen incorporation in amorphous indium gallium zinc oxide (IGZO) on the performance and photo-bias stability of the resulting thin-film transistors (TFTs). It was found that the threshold voltage of IGZO TFTs was negatively shifted without significant loss of the field-effect mobility and ION/OFF ratio with increasing hydrogen concentration, suggesting that interstitial hydrogen can act as a shallow donor. The hydrogen-doped device, however, showed more neg

Abstract— A full‐color 12.1‐in.WXGA active‐matrix organic‐light‐emitting‐diode (AMOLED) display was, for the first time, demonstrated using indium‐gallium‐zinc oxide (IGZO) thin‐film transistors (TFTs) as an active‐matrix backplane. It was found that the fabricated AMOLED display did not suffer from the well‐known pixel non‐uniformity in luminance, even though the simple structure consisting of two transistors and one capacitor was adopted as the unit pixel circuit, which was attributed to the a

Low-temperature (≤400 °C), stackable oxide semiconductors are promising as an upper transistor ingredient for monolithic three-dimensional integration. The atomic layer deposition (ALD) route provides a low-defect, high-quality semiconducting oxide channel layer and enables accurate controllability of the chemical composition and physical thickness as well as excellent step coverage on nanoscale trench structures. Here, we report a high-mobility heterojunction transistor in a ternary indium gall