• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.341.1-341.1
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• 2014

In the advanced material for the next generation display device, transparent amorphous oxide semiconductors (TAOS) are promising materials as a channel layer in thin film transistor (TFT). The TAOS have many advantages for large-area application compared with hydrogenated amorphous silicon TFT (a-Si:H) and organic semiconductor TFT. For the reasonable characteristics of TAOS, The a-IGZO has the excellent performances such as low temperature fabrication (R.T~), high mobility, visible region transparent, and reasonable on-off ratio. In this study, we investigated how the electric characteristics and physical properties are changed as various oxygen ratio when magnetron sputtering. we analysis a-IGZO film by AFM, EDS and I-V measurement. decreasing the oxygen ratio, the threshold voltage is shifted negatively and mobility is increasing. Through this correlation, we confirm the effect of oxygen ratio. We fabricated the bottom-gate a-IGZO TFTs. The gate insulator, SiO2 film was grown on heavily doped silicon wafer by thermal oxidation method. a-IGZO channel layer was deposited by RF magnetron sputtering. and the annealing condition is $350^{\circ}C$. Electrode were patterned Al deposition through a shadow mask(160/1000 um).

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2453-2458
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• 2007

The performance of polysilicon thin film transistor (p-Si TFT) has an important role in the operation of active matrix liquid crystal displays. To fabricate the p-Si TFTs that have uniform characteristics, understanding of the recrystallization mechanism of silicon is crucial. Especially, the analysis of the transient temperature variation and the liquid-solid interface motion is required to find the mechanism. The thermal conductivity is one of the most important parameters to understand the mechanism. In this work, a KrF eximer laser beam was irradiated to amorphous silicon thin films. We measured the transient reflectivity at the wavelength of 633 nm. We carried out the numerical simulation of one dimension conduction equation so that we determined the most well-fitted thermal conductivity by comparing the numerically obtained transient reflectivity with the experimentally measured one. The experimentally determined thermal conductivity of amorphous silicon thin films is 1.5 W/mK.

• 전자통신동향분석
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• 제27권5호
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• pp.109-125
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• 2012

액정 디스플레이의 산업 규모는 놀라운 속도로 확대되고 있다. 그 원동력이 된 것이 박막 트랜지스터(Thin Film Transistor: TFT) 기술의 발전에 있다. 비정질 실리콘(Amorphous Silicon: a-Si) TFT 기술은 대형 액정 TV를 탄생시키고, 저온 폴리실리콘 TFT는 휴대전화 등의 중소형 디스플레이와 AMOLED의 핵심 기술이 되었다. 또한 다양한 TFT 기술 seeds가 계속해서 출현하여 정보 인프라와 생활 스타일에 맞춘 새로운 정보기기의 출현을 예감시키고 있다. 새로운 응용제품의 요구는 새로운 기술 개발의 견인차가 되고 있다. 최근에는 이러한 요구에 따라 산화물 TFT, 마이크로 결정실리콘(microcrystalline Si: ${\mu}c-Si$) TFT, 유기물 TFT 등의 기술도 활발하게 연구개발되고 있다. 본고에서는 지금까지의 TFT 기술 개발의 발전사를 뒤돌아보고 지금부터의 발전 방향을 박막 트래지스터 기술 이노베이션 관점으로부터 전망하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.692-696
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• 2005

In an attempt to fabricate all inclusive display systems we are presenting a study on several elements that would be used as building blocks for all-on-board integrated applications on stainless steel foils. These systems would include in the same substrate all or many of the components needed to drive a flat panel OLED display. We are reporting results on both digital and analog circuits on stainless steel foils. Shift registers running at speeds greater than 1.0MHz are shown as well as oscillators operating at over 40MHz. Pixel circuits for driving organic light emitting diodes are presented. The device technology of choice is that based on poly-silicon TFT technology as it has the potential of producing circuits with good performance and considerable cost savings over the established processes on quartz or glass substrates (amorphous Silicon a-Si:H or silicon on Insulator SOI).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1993년도 춘계학술대회 논문집
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• pp.96-99
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• 1993

대면적 액정 표시판 (Liquid Crystal Display:LCD) panel내(內)의 구동소자인 비정질 실리콘 (amorphous silicon) 박막 트랜지스터 (Thin Film Transistor:TFT)의 구동신호전달 소자특성 향상을 위한 본(本) 연구의 목적은 액정 panel TFT 제조공정 상(上)의 증착금속 전극박막들의 Test Elements Group(TEG) metal line pattern별(別) 전기적 저항특성 평가에 있다. 현(現) TFT 전극용(用)으로 개발이 진행 중(中)인 Aluminum(Al), Tantalum(Ta) 및 Chromium(Cr) 이 특성평가 대상 금속 박막으로 선정 되었으며, 이들 금속막의 증착 thickness 와 TEG metal line width가 저항특성 변수로 성립 되었다. 본(本) 실험을 통해 금속 박막의 TEG line width별(別) 체적(體積)저항 (bulk resistance), 면(面)저항(sheet resistance), 비(比)저항 (resistivity) 및 기판 상(上)의 metal pattern 위치 변화에 따른 전기적 저항 uniformity 특성변화 평가가 있었다. TEG metal line 측정 변위에 따른 저항율의 선형변화 특성도 연구 되었으며, metal line별(別) 전기적 연속, 불연속 배선 단락 특성(electrical continuity test) 관찰도 있었다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.395-398
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• 2004

We developed an a-Si TFT-LCD panel with integrated gate driver circuit using a standard 5-MASK process. To minimize the effect of the a-Si TFT current and LC's capacitance variation with temperature, we developed a new a-Si TFT circuit structure and minimized coupling capacitance by changing vertical architecture above gate driver circuit. Integration of gate driver circuit on glass substrate enables single chip and 3-side free panel structure in a-Si TFT-LCD of QVGA(240$^{\ast}$320) resolution. And using double ASG structure the dead space of TFT-LCD panel could be further decreased.

• ETRI Journal
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• 제34권4호
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• pp.633-636
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• 2012

A dynamic analysis of an amorphous silicon (a-Si) thin film transistor liquid crystal display (TFT-LCD) pixel is presented using new a-Si TFT and liquid crystal (LC) capacitance models for a Simulation Program with Integrated Circuit Emphasis (SPICE) simulator. This dynamic analysis will be useful when predicting the performance of LCDs. The a-Si TFT model is developed to accurately estimate a-Si TFT characteristics of a bias-dependent gate to source and gate to drain capacitance. Moreover, the LC capacitance model is developed using a simplified diode circuit model. It is possible to accurately predict TFT-LCD characteristics such as flicker phenomena when implementing the proposed simulation model.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.445-446
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• 2005

This letter reports the fabrication of polycrystalline silicon thin-film transistors (poly-Si TFT) on flexible plastic substrates using amorphous silicon (a-Si) precursor films by sputter deposition. The a-Si films were deposited with mixture gas of argon and helium to minimize the argon incorporation into the film. The precursor films were then laser crystallized using XeCl excimer laser irradiation and a four-mask-processed poly-Si TFTs were fabricated with fully self-aligned top gate structure.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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• pp.44-47
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• 2000

본 연구는 α-Si:H TFT(Amorphous Silicon Thin Film Transistor)를 대체 할 펜타센을 활성층으로 사용하는 박막 트랜지스터를 제작에 관한 것이다. 유기 박막 트랜지스터는 유기발광소자와 함께 유연한 디스플레이에 응용된다. 펜타센 박막 트랜지스터의 제작은 채널 길이 25㎛, 70㎛, 소스, 드레인, 게이트 전극으로 Au을 lift off 공정으로 제작하였으며, 펜타센은 OMBD(Organic Molecular Beam Deposition)로 기판온도를 80℃로 유지하여 증착하였다. 제작된 소자로부터 트랜지스터 전류-전압 특성곡선을 측정하였고, 게이트에 의한 채널의 전도도가 조절됨을 확인하였다. 그리고, 전달특성곡선으로부터 문턱전압과 전계효과 이동도를 추출하였다.