• 한국진공학회지
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• 제7권s1호
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• pp.123-133
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• 1998

Amorphous silicon (a-Si) was crystallized by metal induced crystallization using metal solution. The a-Si films spin coated with a 50,000 ppm Ni solution were crystallized at as low as $500^{\circ}C$. Needlelike morphology, developed as a result of the migration of $NiSi_2$, precipitates, appears in the MIC poly-Si. The growth of the needlelike crystallites proceeds to a direction parallel to (111). The crystallization temperature can be lowered to $450^{\circ}C$ by Au addition. The enhancement of crystallization results from the decrease of interfacial energy at the NiSi2/Si interface by Au addition.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.199-199
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• 2008

이 실험은 NVM의 Oxide, Nitride, Oxide nitride층별 blocking, trapping and tunneling 속성에 대해서 밝히고자 한다. gate 전극은 값싸고 전도도가 좋은 알루미늄을 사용한다. 유리기판위에 Silicon nitride층을 20nm로 코팅하고 Silicon dioxide층을 10nm로 코팅한다. 그리고 amorphous Silicon material이 증착된다. Poly Silicon은 Solid Phase Crystallization 방법을 사용하였다. 마지막 공정으로 p-doping은 ion shower에 의한 방법으로 drain과 source 전극을 생성하였다. gate가 biasing 될 때, p-channel은 source와 drain 사이에서 형성된다. Oxide Nitride Oxide nitride (ONO) 층은 각각 12.5nm/20nm/2.3nm의 두께로 만들었다. 전하는 Program process 중에 poly Silicon층에서 Silicon Oxide nitride tunneling층을 통하여 움직이게 된다. 그리고 전하들은 Silicon Nitride층에 머무르게 된다. 그 전하들은 erasing process 중에 trapping 층에서 poly Silicon 층으로 되돌아 간다. Silicon Oxide blocking층은 trapping층으로 전하가 나가는 것을 피하기 위하여 더해진다. 이 논문에서 Programming process와 erasing process의 Id-Vg 특성곡선을 설명한다. Programming process에 positive voltage를 또는 erasing process에 negative voltage를 적용할 때, Id-Vg 특성 곡선은 왼쪽 또는 오른쪽으로 이동한다. 이 실험이 보여준 결과값에 의해서 10년 이상의 저장능력이 있는 메모리를 만들 수 있다. 그러므로, NVM의 중요한 두 가지 성질은 유지성과 내구성이다.

• 대한기계학회논문집B
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• 제36권10호
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• pp.1019-1023
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• 2012

본 연구에서는 새로운 알루미늄 유도 결정화 공정을 제안하였다. 알루미늄 박막에 직접 3 A의 정전류를 인가하여 $1cm{\times}1cm$ 넓이의 두께 200 nm 비정질 실리콘 박막을 수십 초 내에 결정화하는 방법이다. 결정화된 다결정 실리콘 박막은 520 $cm^{-1}$ 에서의 라만 분광 피크를 통해 확인할 수 있었다. 공정 후, 알루미늄이 식각된 다결정 실리콘 박막은 다공성 구조임을 SEM 을 통하여 확인할 수 있었다. 또 한, 이차이온질량분석(secondary ion mass spectroscopy)에서 알루미늄 농도가 $10^{21}cm^{-3}$으로 헤비 도핑된 것을 확인 할 수 있었으며, 실시간으로 측정된 열화상 카메라의 결과를 통해 결정화는 820 K 근처에서 일어나는 것을 확인할 수 있었다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.59.1-59.1
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• 2010

Aluminum-induced crystallization (AIC) of amorphous silicon (a-Si) is studied with the structure of a glass/Al/$SiO_2$/a-Si, in which the $SiO_2$ layer has micron-sized laser holes in the stack. An oxide layer between aluminum and a-Si thin films plays a significant role in the metal-induced crystallization (MIC) process determining the properties such as grain size and preferential orientation. In our case, the crystallization of a-Si is carried out only through the key hole because the $SiO_2$ layer is substantially thick enough to prevent a-Si from contacting aluminum. The crystal growth is successfully realized toward the only vertical direction, resulting a crystalline silicon grain with a size of $3{\sim}4{\mu}m$ under the hole. Lateral growth seems to be not occurred. For the AIC experiment, the glass/Al/$SiO_2$/a-Si stacks were prepared where an Al layer was deposited on glass substrate by DC sputter, $SiO_2$ and a-Si films by PECVD method, respectively. Prior to the a-Si deposition, a $30{\times}30$ micron-sized hole array with a diameter of $1{\sim}2{\mu}m$ was fabricated utilizing the femtosecond laser pulses to induce the AIC process through the key holes and the prepared workpieces were annealed in a thermal chamber for 2 hours. After heat treatment, the surface morphology, grain size, and crystal orientation of the polycrystalline silicon (pc-Si) film were evaluated by scanning electron microscope, transmission electron microscope, and energy dispersive spectrometer. In conclusion, we observed that the vertical crystal growth was occurred in the case of the crystallization of a-Si with aluminum by the MIC process in a small area. The pc-Si grain grew under the key hole up to a size of $3{\sim}4{\mu}m$ with the workpiece.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2004년도 춘계학술발표대회 및 제6회 신소재 심포지엄
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• pp.60-60
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• 2004

• 한국재료학회:학술대회논문집
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• 한국재료학회 2002년도 추계학술발표강연 및 논문개요집
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• pp.39-39
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• 2002

• 한국재료학회지
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• 제14권7호
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• pp.477-481
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• 2004

High quality polycrystalline silicon is very critical part of the high quality thin film transistor(TFT) for display devices. Metal induced lateral crystallization(MILC) is one of the most successful technologies to crystallize the amorphous silicon at low temperature(below $550^{\circ}C$) and uses conventional and large glass substrate. In this study, we observed that the MILC behavior changed with abrupt variation of the amorphous silicon active pattern width. We explained these phenomena with the novel MILC mechanism model. The 10 nm thick Ni layers were deposited on the glass substrate having various amorphous silicon patterns. Then, we annealed the sample at $550^{\circ}C$ with rapid thermal annealing(RTA) apparatus and measured the crystallized length by optical microscope. When MILC progress from narrow-width-area(the width was $w_2$) to wide-width-area(the width was $w_1$), the MILC rate decreased dramatically and was not changed for several hours(incubation time). Also the incubation time increased as the ratio, $w_1/w_2$, get larger. We can explain these phenomena with the tensile stress that was caused by volume shrinkage due to the phase transformation from amorphous silicon to crystalline silicon.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.96.2-96.2
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• 2010

The surface morphology and structural properties of polycrystalline silicon (poly-Si) films made in-situ aluminum induced crystallization at various substrate temperature (300~600) was investigated. Silicon films were deposited by hot-wire chemical vapor deposition (HWCVD), as the catalytic or pyrolytic decomposition of precursor gases SiH4 occurs only on the surface of the heated wire. Aluminum films were deposited by DC magnetron sputtering at room temperature. continuous poly-Si films were achieved at low temperature. from cross-section TEM analyses, It was confirmed that poly-Si above $450^{\circ}C$ was successfully grown on and poly-Si films had (111) preferred orientation. As substrate temperature increases, Si(111)/Si(220) ratio was decreased. The electrical properties of poly-Si film were investigated by Hall effect measurement. Poly-Si film was p-type by Al and resistivity and hall effect mobility was affected by substrate temperature.

• 한국전기전자재료학회논문지
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• 제13권2호
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• pp.95-100
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• 2000

For the well-controlled growing in-situ heavily phosphorus doped polycrystalline Si films directly on Si wafer by reduced pressure chemical vapor deposition, a study is made of the two step growth. When in-situ heavily phosphorus doped Si films were deposited directly on Si (100) wafer, crystal structure in the film is not unique, that is, the single crystal to polycrystalline phase transition occurs at a certain thickness. However, the well-controlled polycrtstalline Si films deposited by two step growth grew directly on Si wafers. Moreover, the two step growth, which employs crystallization of grew directly on Si wafers. Moreover, the two step growth which employs crystallization of amorphous silicon layer grown at low temperature, reveals crucial advantages in manipulating polycrystal structures of in-situ phosphorous doped silicon.

• 한국세라믹학회지
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• 제24권4호
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• pp.364-368
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• 1987

The Si5AION7 specimens containing 20% YAG composition have been sintered and then heat treated to induce the crystallization of the matrix glassy phase. Crystallization of YAG phase during the heat treatment was detected from the X-ray diffraction patterns and the consequent changes in room temperature toughness as well as in microstructures were investigated. Almost all the glassy boundary phase were found to crystallize even after 5 minutes of heat treatment and the KC at room temperature decreased accordingly. The results show that the matrix crystallization can be induced by slow cooling from the sintering temperature.