• Proceedings of the Materials Research Society of Korea Conference
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• 2001.11a
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• pp.66-66
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• 2001

• Journal of Information Display
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• v.4 no.4
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• pp.1-3
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• 2003

For excimer laser annealing (ELA), energy density, number of pulses, beam uniformity, and condition of initial amorphous Si (a-Si) films are significant factors contributing to the final microstructure and the performance of low-temperature polycrystalline Si (LTPS) TFTs. Although the process and equipment have been significantly improved, the environmental factors associated with initial amorphous Si (a-Si) films and process conditions are yet to be optimized.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.155-156
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• 2000

We propose a new in-situ fluorine passivation of poly-Si TFTs by excimer laser annealing to reduce the trap density and improve the reliability significantly. This improvement is due to the formation of stronger Si-F bonds than Si-H bonds which passivate the trap states.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.9
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• pp.623-627
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• 1999

We report a new in-situ fluorine passivation method without in implantation by employing excimer laser annealing of $SiO_{x}F_{y}$/a-Si structure and its effects on p-channel poly-Si TFTs. The proposed method doesn't require any additional annealing step and is a low temperature process because fluorine passivation is simultaneous with excimer-laser-induced crystallization. A in-situ fluorine passivation by the proposed method was verified form XPS analysis and conductivity measurement. From experimental results, it has been shown that the proposed method is effective to improve the electrical characteristics, specially field-effect mobility, and the electrical stability of p-channel poly-Si TFTs. The improvement id due to fluorine passivation, which reduces the trap state density and forms the strong Si-F bonds in poly-Si channel and $SiO_2/poly-Si$ interface. From these results, the high performance poly-Si TFTs canbe obtained by employing the excimer-laser-induced fluorine passivation method.

• Journal of Information Display
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• v.1 no.1
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• pp.25-28
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• 2000

We propose a new in-situ fluorine passivation of poly-Si TFTs using excimer laser annealing to reduce the trap state density and improve reliability significantly. To investigate the effect of an in-situ fluorine passivation, we have fabricated fluorine-passivated p-channel poly-Si TFTs and examined their electrical characteristics and stability. A new in-situ fluorine passivation brought about an improvement in electrical characteristic. Such improvement is due to the formation of stronger Si-F bonds than Si-H bonds in poly-Si channel and $SiO_2$/Poly-Si interface.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.874-876
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• 2003

Blue light-emitting polyfluorene derivatives, poly[9,9-bis(4'-n-octyloxyphenyl) fluorene] (PBOPF), poly[9,9-bis(2'-ethylhexyl)]fluorene (PBEHF) and copolymers of PBOPF and PBEHF were synthesized through Ni(0) mediated polymerization and their light-emitting properties were investigated. The PBEHF thin film showed significant excimer band in PL spectra after thermal annealing at 100 $^{\circ}C$ for 2h. But no significant excimer emission was observed in the PL spectra of the PBOPF and the copolymers even after thermal annealing suggesting that BOPF unit effectively suppressed the excimer emission.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1032-1035
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• 2009

Several different production technologies for Low-Temperature Poly-Silicon (LTPS) have been proposed over the last years. However, finally the progress in Excimer-laser-based crystallization has lead to the best cost-to-performance ratio of LTPS manufacturing for use in active-matrix-based displays. In this paper, we report on recent and significant technical advances in light sources, optical beam deliveries and beam irradiation systems targeted at enabling ultra-uniform mura-free LTPS active-matrix backplanes while simultaneously lowering production costs and increasing throughput.

• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.130-133
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• 2002

엑시머 레이저를 이용한 저온($450^{\circ}C$ 이하) 다결정 실리콘 박막 트랜지스터 제작 시, 소오스/드레인 이온 주입에 의한 실리콘 박막의 격자 손상은 엑시머 레이저 어닐링(Excimer Laser Annealing; ELA) 방법으로 치유한다. 그러나 게이트 전극 모서리에서의 레이저광 회절 현상으로 인해 소오스/드레인 접합부에 도달하는 레이저 에너지 밀도가 감소하여 다량의 결정 결함이 치유되지 못한 채 남게 된다. 이러한 결정 결함은 박막 트랜지스터의 전계 효과 이동도를 저하시키는 요인이 된다. 새롭게 제안한 사선 입사 엑시머 레이저 어닐링(Oblique Incidence Excimer Laser Annealing; OI-ELA) 방법으로 소오스/드레인 접합부의 결정 결함을 제거하고 다결정 박막 트랜지스터의 특성을 향상시켰다.

• Journal of the Optical Society of Korea
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• v.5 no.1
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• pp.1-4
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• 2001

The results of investigating $SiL_{2,3}$/ X-ray emission valence spectra of amorphous silicon films irradiated by excimer laser are presented. It is found that laser annealing leads to crystallization of amorphous silicon films and the crystallinity increases with the laser energy density from 250 to 400 mJ/$\textrm{cm}^2$. The vertical structure of the film is investigated by changing the accelerating voltage on the X-ray tube, and the chemical and structural state of Si$_3$N$_4$ buffer layer is found not to be changed by the excimer laser treatment.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.1
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• pp.24-29
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• 2000

We propose a simple method to control the crystallization depth of amorphous silicon (a-Si) deposited by PECVD or LPCVD during the excimer laser annealing (ELA). Employing the new method, we have formed poly-Si/a-Si double film and fabricated a new poly-Si TFT with vertical a-Si offsets between the poly-Si channel and the source/drain of TFT without any additional photo-lithography process. The maximum leakage current of the new poly-Si TFT decreased about 80% due to the highly resistive vertical a-Si offsets which reduce the peak electric field in drain depletion region and suppress electron-hole pair generation. In ON state, current flows spreading down through broad a-Si cross-section in the vertical a-Si offsets and the current density in the drain depletion region where large electric field is applied is reduced. The stability of poly-Si TFT has been improved noticeably by suppressing trap state generation in drain region which is caused by high current density and large electric field. For example, ON current of the new TFT decreased only 7% at a stress condition where ON current of conventional TFT decreased 89%.