• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.69-74
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• 2004

System-on-glass technology made with low temperature poly-Si TFT has been rapidly advancing in recent years. We have developed a low-power, narrow edged frame, 1.9inch system-on-glass LCD which fully integrates a 16-bit RGB interface driver and all power circuits required for driving the LCD. In this paper, the latest poly-Si TFT circuit technologies used in the newly developed LCD are discussed. The development trends are also reviewed.

• Journal of Information Display
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• v.7 no.3
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• pp.5-8
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• 2006

A novel a-Si TFT integrated gate driver circuit using multi-thread driving has been developed. The circuit consists of two independent shift registers alternating between the two modes, "wake" and "sleep". The degradation of the circuit is retarded because the bias stress is removed during the sleep mode. It has been successfully integrated in 14.1-in. XGA LCD Panel, showing enhanced stability.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1649-1652
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• 2006

2.22-inch qVGA $(240{\times}320)$ amorphous silicon thin film transistor liquid active matrix crystal display (${\alpha}$- Si TFT-AMLCD) panel has been successfully demonstrated employing a 2.5 um fine-patterning technology by a wet etch process. Higher resolution 2.22-inch qVGA LCD panel with an aperture ratio of 58% can be fabricated because the 2.5 um fine pattern formation technique is combined with high thermal photo-resist (PR) development. In addition, a novel concept of unique ${\alpha}$-Si TFT process architecture, which is advantageous in terms of reliability, was proposed in the fabrication of 2.22-inch qVGA LCD panel. Overall results show that the 2.5 um finepatterning is a considerably significant technology to obtain higher aperture ratio for higher resolution ${\alpha}$-Si TFT-LCD panel realization.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.745-748
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• 2007

Hydrogenated amorphous silicon thin film transistors (a-Si:H TFTs) were fabricated on a flexible metal substrate at $150\;^{\circ}C$. To increase the stability of the flexible a-Si:H TFTs, they were thermally annealed at $230\;^{\circ}C$. The field effect mobility was reduced because of the strain in a- Si:H TFT under thermal annealing.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.964-967
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• 2009

A new hybrid-type touch screen panel (TSP) has been developed based on a-Si:H TFT which can detect the change of both $C_{LC}$ and photo-current. This TSP can detect the difference of $C_{LC}$ between touch and no-touch states in unfavorable conditions such as dark ambient light and shadows. The hybrid TSP sensor consists of a detection area which includes one TFT for photo sensing and two TFTs for amplification. Compared to a single internal capacitive TSP or an optical sensing TSP, this new proposed hybrid-type TSP enables larger sensing margin due to embedding of both optical and capacitive sensors.

• Journal of Information Display
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• v.2 no.2
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• pp.1-6
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• 2001

A $1"{\times}l"$, $512{\times}512$ poly-Si TFT-LCD with a new integrated 8-bit parallel-serial digital data driver was proposed and designed. For high resolution, the proposed parallel-serial digital driver used serial video data rather than parallel ones. Thus, digital circuits for driving one column line could be integrated within very small width. The parallel-serial digital data driver comprised of shift registers, latches, and serial digital-to-analog converters (DAC's). We designed a $1"{\times}l"$, $512{\times}512$ poly-Si TFT-LCD with integrated 8-bit parallel-serial digital data drivers by a circuit simulator which has physical-based analytical model of poly-Si TFT's. The fabricated shift register well operated at 2 MHz and $V_{DD}$=10V and the fabricated poly-Si TFT serial DAC's, which converts serial digital data to an analog signal, could convert one bit within $2.8{\mu}s$. The driver circuits for one data line occupied $8100{\times}50{\mu}m^2$ with $4{\mu}m$ design rule.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.747-751
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• 2006

The hydrogenated amorphous silicon thin film transistor (a-Si:H TFT) with copper as source and drain electrode has been fabricated to obtain its transfer characteristics and stressed with positive and negative bias to investigate the instability variation comparing to conventional MoW-Al based TFT device. The results show that there is no copper diffusion into active layer of a-Si:H TFT, even during the thermal process. In addition, a 15-inch XGA a Si:H TFT LCD display utilizing Cu as gate electrodes has been developed.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.940-943
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• 2005

The characteristics of a-Si:H TFTs with silicon oxide as passivation layer were reported. It was studied that the insulating characteristics and step coverage characteristics of low temperature silicon oxide before applying to a-Si:H TFT fabrications. With the optimum deposition conditions considering electrical and deposition characteristics, low temperature silicon oxide was applied to a-Si:H TFTs. The changes in characteristics of a-Si:H TFTs were analyzed after replacing silicon nitride passivation layer with low temperature silicon oxide layer. This low temperature silicon oxide can be adapted to high resolution a-Si:H TFT LCD panels.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1176-1178
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• 2007

A novel integrated a-Si:H gate driver with high reliability has been designed and simulated. Since the a-Si:H TFT is easily degraded by gate bias stress, we should optimize the circuit considering the threshold voltage shift. The conventional circuit shows voltage drop at the input stage by threshold voltage of the TFT, however, the proposed circuit dose not shows voltage drop and keeps constant regardless of threshold voltage shift of the TFT.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.3
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• pp.264-268
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• 2005

A 2.2-inch QCIF+(176${\times}$RGB${\times}$220) TFT-LCD with integrated row driver was developed using a standard amorphous silicon TFT technology. At low temperature, the integrated row driver operation is dramatically effected by the electron drift mobility reduction(■50 %) and the threshold voltage shift (■1V) of the a-Si TFT. We studied the dependency of circuit design and found that higher on-current circuit is important to guarantee good operation in wide temperature range.