Sang Wook Kim

We successfully integrated the high performance oxide thin film transistors with double active layers. The active layer is composed of IZO (or ITO) and GIZO layers. The TFT with ITO/GIZO double active layer shows a high mobility of 104 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /V.sec, the acceptable threshold voltage of about 0.5 V and the low Vth shift less than 1 V under voltage stress. These are very promising results for applica

Rapid progress in the portable and flexible electronic devises has stimulated supercapacitor research towards the design and fabrication of high performance flexible devices. Recent research efforts for flexible supercapacitor electrode materials are highly focusing on graphene and chemically modified graphene owing to the unique properties, including large surface area, high electrical and thermal conductivity, excellent mechanical flexibility, and outstanding chemical stability. This invited r

We investigate the low-frequency noise (LFN) behaviors of amorphous indium-gallium-zinc oxide thin-film transistors in the subthreshold, Ohmic, and saturation regimes. Measured LFNs are proportional to 1/fγ, with γ=0.8–0.9 in all operation regimes. It is found that the LFN behavior follows the carrier number fluctuation model in the subthreshold regime, whereas in the Ohmic and saturation regimes, it agrees well with the bulk mobility fluctuation model. We also observe that the origin of 1/f noi

Efficient nonresonant optical pumping of a high-Q scar mode in a two-dimensional quadrupole-deformed microlaser has been demonstrated based on ray and wave chaos. Threefold enhancement in the lasing power was achieved at a properly chosen pumping angle. The experimental result is consistent with ray tracing and wave overlap integral calculations.

We have demonstrated self-aligned top-gate amorphous oxide TFTs for large size and high resolution displays. The processes such as source/drain and channel engineering have been developed to realize the self-aligned top gate structure. Ar plasma is exposed on the source/drain region of active layer to minimize the source/drain series resistances. To prevent the conductive channel, N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O plasma is

We investigated the effects of gadolinium (Gd) incorporation into indium-zinc-oxide (IZO) thin-film transistors (TFTs) using radio-frequency cosputtering of IZO and Gd. A gadolinium-indium-zinc-oxide (Gd-IZO) TFT with 2.4 at.% Gd content had saturation-mode field-effect mobility, threshold voltage, and switching ratio (on current/off current) of 6.6 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> V <sup xmlns:mml="http://www.w3.org/1998/M

We systematically investigated the role of the Si Ox and/or SiONx passivation layer in the amorphous hafnium indium zinc oxide (HIZO) thin film transistors (TFTs) under a negative bias temperature illumination stress (NBTIS) condition. The device instability of the TFTs with a SiOx passivation layer [threshold voltage shift (?? V th) ???-6.5 V] is better than that of the TFTs with a SiO N x passivation layer (?? Vth ???-8.5 V) in the atmosphere. However, the devices with the Si Ox passivation la

We fabricated lanthanum indium zinc oxide (IZO) (La-IZO) thin-film transistors (TFTs) using radio frequency cosputtering of IZO and lanthanum. The field-effect mobility and switching ratio of the La-IZO TFTs were 4.2 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ·V <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> ·s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="ht

We report efficient nonresonant optical pumping based on turnstile transport in a chaotic microcavity laser. We observed more than tenfold enhancement in the pumping efficiency at a particular pumping angle and at a particular boundary position of the microcavity while these angle and position are consistent with the turnstile transport mechanism in chaotic ray dynamics. The pumping efficiency distribution resembles that of the output emission for the same cavity, supporting the concept of time-

Abstract We have developed 2.2‐inch transparent active matrix organic light emitting diode AMOLED with semitransparent cathode contact technology on the organic layer of electroluminescent device. The transparent AMOLED shows the emission from both the bottomside and the topside. The contrast ratio was enhanced because of non‐reflecting cathode with respect to the conventional display and when the device was turned off, it showed about 20% of transparency

The correlations between mechanical and electrical properties of ethylene propylene diene terpolymer (EPDM) compounds and carbon black types and levels applied are studied. Tensile strength increases with an increase of the carbon black, especially for carbon black with higher surface area. Tracking resistance of EPDM compounds improves when a small amount of relatively nonconductive carbon blacks are added to EPDM compounds, whereas conductive carbon blacks decrease both dielectric properties a

In this paper, we propose a crowdsourcing-based approach to solving skyline queries with incomplete data. Our main idea is to leverage crowds to infer the pair-wise preferences between tuples when the values of tuples in some attributes are unknown. Specifically, our proposed solution considers three key factors used in existing crowd-enabled algorithms: (1) minimizing a monetary cost in identifying a crowdsourced skyline by using a dominating set, (2) reducing the number of rounds for latency b

The patterning of sub-80 nm contact holes and trenches by ArF lithography is very challenging. To solve this problem, several technologies have been proposed, including thermal flow, resolution enhancement of lithography assisted by chemical shrink (RELACS), and shrink assist film for enhanced resolution (SAFIER). In this paper, we compare these processes in order to determine the advantages and disadvantages, and to gain an understanding on their mechanism on the basis of the performances of ea