• Journal of Information Display
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• v.10 no.4
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• pp.137-142
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• 2009

Transparent top-gate Al-Zn-Sn-O (AZTO) thin-film transistors (TFTs) with an $Al_2O_3$ protective layer (PL) on an active layer were studied, and a transparent 2.5-inch QCIF+AMOLED (active-matrix organic light-emitting diode) display panel was fabricated using an AZTO TFT backplane. The AZTO active layers were deposited via RF magnetron sputtering at room temperature, and the PL was deposited via two different atomic-layer deposition (ALD) processes. The mobility and subthreshold slope were superior in the TFTs annealed in vacuum and with oxygen plasma PLs compared to the TFTs annealed in $O_2$ and with water vapor PLs, but the bias stability of the TFTs annealed in $O_2$ and with water vapor PLs was excellent.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1664-1667
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• 2007

The belt source evaporation is for the large size AMOLED devices to re-sublimate the organic film deposited on the metal plate. Using the plane source, the PL spectrum of the doped organic film has been studied for the first time. The PL peak of the pure Alq3 film was 512nm and that of the pure Rubrene was 557nm. The PL peak of the 2% Rubrene doped Alq3 film was shifted to $536{\pm}2nm$. The PL peak wavelength measured at the front surface of the film and at the back surface of the film was measured as nearly same as that the doping ratio maintains uniform within the film thickness. In conclusion, the doping control of the organic film becomes real using the belt type plate sublimation deposition.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1267-1268
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• 2008

The two-shot SLS method has recently been successfully implemented in volume manufacturing of advanced LTPS-based LCDs. In this presentation, we discuss how the approach is also well suited for being implemented in high-throughput and high-yield manufacturing of large AMOLED displays on large glass substrates.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.109-112
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• 2008

The grain size of JIC poly-Si can be varied from few tens of nanometers to the one having the larger grain size exceeding that of excimer laser crystallized (ELC) poly-Si according transmission electron microscopy. JIC poly-Si exhibits an excellent uniformity with regards to the grain size. We report here the blanket crystallization of the large area using the $2^{nd}$ generation glass substrate.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.413-418
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• 2006

Highly stable thin-film transistor (TFT) pixel employing both low temperature polycrystalline silicon (LTPS) and amorphous silicon (a-Si) for active matrix organic light emitting diode (AMOLED) is discussed. ELA (excimer laser annealing) LTPS-TFT pixel should compensate $I_{OLED}$ variation caused by the non-uniformity of LTPS-TFT due to the fluctuation of excimer laser energy and amorphous silicon TFT pixel is desired to suppress the decrease of $I_{OLED}$ induced by the degradation of a-Si TFT. We discuss various compensation schemes of both LTPS and a-Si TFT employing the voltage and the current programming.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1436-1439
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• 2005

A novel current-type data driver for active matrix organic light emitting diode (AMOLED) is proposed for current uniformity enhancement among its output channels. New architecture is composed of shadow DACs that precharge output stages, a single-real DAC that correct the output level to a real target current level and output stages that operate in 3 states of sampling, correcting and driving. Simulation results show that the proposed driving method and circuits improve the current uniformity among output channels of a current-type driver IC.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.665-667
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• 2005

VIATRON TECHNOLOGIES has developed FE-RTP system that enables LTPS LCD and AMOLED manufacturers to produce poly-Si films at low cost, high throughput, and high yield. The system employs sequential heat treatment methods using temperature control and rapid thermal processor modules. The temperature control modules provide exceptionally uniform heating and cooling of the glass substrates to within ${\pm}2^a\;C$. The rapid thermal process that combines heating with field induction accelerates the treatment rates. The new FE-RTP system can process $730{\times}920mm$ glass substrates as thin as 0.4 mm. The uniform nature of poly-Si films produced by FE-RTP resulted in AMOLED panels with no laser-Muras. Furthermore, FE-RTP system also showed superior performances in other heat treatment processes involved in poly-Si TFT fabrications, such as dopant activation, gate oxide densification, hydrogenation, and pre-compaction.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.746-748
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• 2004

a-Si TFTs with field-effect mobility of 1.2 $cm^2$/V-s have been fabricated on plastic substrate. Pixel circuits on plastic for AMOLED were made with the same low-temperature fabrication process. The circuits compensate for $V_T$-shift, exhibit high output current, retain functionality and drive current level during long-time continuous operation.

• Journal of Convergence for Information Technology
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• v.9 no.3
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• pp.75-81
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• 2019

In this work, we investigated a low temperature polycrystalline silicon (LTPS) thin film transistors fabrication process on polymer layers. Dehydrogenation and activation processes were performed by a furnace annealing at a temperature of $430^{\circ}C$ for 2 hr. The crystallization of amorphous silicon films was formed by excimer laser annealing (ELA) method. The p-type device performance, fabricated by polycrystalline silicon (poly-Si) films, shows a very good performance with field effect mobility of $77cm^2/V{\cdot}s$ and on/off ratio current ratio > $10^7$. We believe that the poly-Si formed by a LTPS process may be well suited for fabrication of poly-Si TFTs for bendable panel displays such as AMOLED that require circuit integration.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1789-1791
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• 2007

We fabricated OTFT-OLED display panel by using Ag-paste for source and drains electrode of OTFTs. The OTFTs were fabricated by solution processes such as spin-coating for PVP gate dielectric and screen printing for S/D electrodes with Ag-paste, except pentacene active layer which was deposited by evaporation. The mobility was 0.024 cm2/V.sec , off state current ${\sim}10-11A$, threshold voltage 7.6 V and on/off current ratio ${\sim}105$. The panel consisted of 16 x 16 pixels and each pixel consisted of 2 OTFTs, 1 Capacitor and 1 OLED. The pixels successfully worked in terms of current magnitude supplied to OLED and the control ability of driving and switching OTFTs.