• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.2
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• pp.12-16
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• 2000

The electrical characteristics of n-channel LDD structured poly-Si TFT's have been systematically investigated. It have been found that the LDD regions act as the effect of series resistance and reducing the electric field. Kink effect is disappeared and off current is greatly reduced, while on current is slightly reduced. On/off current ratio graph shows that LDD device's switching characteristic is better than that of conventional device. As a result of study, it is concluded that the effect of electric field's reduction is more dominant than that of series resistance.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.3
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• pp.96-106
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• 1996

One of the major problems for poly-Si TFTs is the large off state leakage current. LDD (lightly doped drain) and offset gated structures have been employed in order to reduce the leakage current. However, these structures also redcue the oN current significantly due to the extra series resistance caussed by the LDD or offset region. It is desirable to have a device which would have the properties of the offset gated structure in the OFF state, while behaving like a fully gated device in the oN state. Therefore, we propose a new thin film transistor with pnp junction gate which reduce the leakage curretn during the OFF state without sacrificing the ON current during the ON state.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.7
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• pp.522-526
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• 1998

We have fabricated a LDD structured polysilicon thin film transistor with low leakge current and the optimized LDD length has been obtained. The device performance is improved is improved by hydrogen passivation process. The on.off current ratio of poly0Si TFT s with $0.5{\mu}m$ and $1.0{\mu}m$ LDD length is much higher than that of conventional structured device due to the decrease of leakege current. The optimized LDD length may be $0.5{\mu}$ from the experimental data such as on/off current ratio, threshold voltage and hydrogenation effect.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.75-75
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• 2012

박막 트랜지스터(TFT: Thin-Film-Transistor)는 미래 산업에 여러 가지로 사용 가능한 소자이기 때문에, 많은 연구가 진행되고 있고 그 성능이 계속 향상되고 있다. 특히, 평판 디스플레이인 AMLCD, AMOLED, 전자 종이 등이 모두 유리 혹은 플라스틱 기판에 향성된 TFT 어레이를 이용하고 있다. 현재 상업화에 응용되는 TFT는 비정질 실리콘과 저온 다결정 실리콘이며, 유기반도체 및 산화물 반도체 TFTs에 대한 연구가 매우 활발히 진행되고 있다. 본 발표에서는 산화물 반도체 TFT와 유기 반도체 TFT 기술 및 AMOLED에의 응용 기술 이슈에 대해 논의할 예정이다.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.801-802
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• 1992

Poly Si TFTs have been fabricated from low temperature annealed a-Si films. I-V and C-V characteristics in the off-state region were measured. Analytical model for the leakage current in the off-state was suggested. In the measurement, capacitance increased abruptly with Increasing gate and drain voltage. This phenomena is attributed to the leakage current.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.507-510
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• 1998

Performance of AMLCD pixels depends on the electrical characteristics of thin film transistor switches. The high quality of LCD can be obtained by minimizing the process and device variations of TFT. The effect of process and device factors on poly-Si TFT characteristics are calculated by ATHENA and ATLAS, and the optimized design windows based on statistical design of experiment are suggested for high performance 20 inch LCD are suggested for high performance 20 inch LCD monitors.

• Journal of the Korean Society of Radiology
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• v.17 no.4
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• pp.625-631
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• 2023

The important requirement of industrial dynamic X-ray detector operating under high tube voltage up to 450 kVp for 24 hours and 7 days is to obtain significantly high radiation resistance. This study presents the radiation resistance characteristics of various thin film transistors (TFTs) with a-Si, poly-Si and IGZO semiconducting layers. IGZO TFT offering dozens of times higher field effect mobility than a-Si TFT was processed with highly hydrogenated plasma in between IGZO semiconducting layer and inter-layered dielectric. The hydrogenated IGZO TFT showed most sustainable radiation resistance up to 10,000Gy accumulated, thus, concluded that it is a sole switching device in X-ray imaging sensor offering dynamic X-ray imaging at high frame rate under extremely severe radiation environment such as automated X-ray inspection.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.3
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• pp.39-46
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• 1994

CMOS LCD driving circuits using poly-Si TFT have been designed and basic blocks including test patterns have been fabricated. Column driver drives the pixels by block because polu-Si TFT can not operate at the speed of video signal. Row driver has mode selection circuit which can select a mode between interlacing mode and non-interlacing mode. Experimental results show shift register can operate at 1MHz colck frequency with 4pF load.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.322-325
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• 2000

N-channel poly-Si TFT, Processed by Solid Phase Crystalline(SPC) on a glass substrate, has been investigated by measuring its electrical properties before and after electrical stressing. It is observed that the threshold voltage shift due to electrical stress varies with various stress conditions. Threshold voltages measured in 1.5$\mu\textrm{m}$ and 3$\mu\textrm{m}$ poly-Si TFTs are 3.3V, 3.V respectively. With the threshold voltage shia the degradation of transconductance(G$\_$m/) and subthreshold swing(S) is also observed.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.12
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• pp.29-34
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• 2000

The effects of electrical stress on MILC(Metal Induced Lateral Crystallization) poly-Si TFT were studied. After the electrical stress was applied on the TFT’s which were fabricated by MILC process, off-state(VG<0V) current was reduced by $10^2{\sim}10^4$ times. However, when the device on which electrical stress was applied was annealed in furnace, the off-state current increased as annealing temperature increased. From the dependence of off-state current on the post-annealing temperature, activation energy of the trap states in MILC poly-Si thin films was calculated to be 0.34eV.