• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.396-396
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• 2007

Highly ordered pore structures as a template for formation of seeds have been prepared by the self-organization process of aluminum oxidation. The a-Si films were deposited on the anodic alumina films and crystallized by laser irradiation. It was found that un-melted part of fine poly-Si grain formed by explosive crystallization (EX) lead super lateral growth(SLG) and occluded with neighbor grains. The crystallized grains along the distribution of seeds were obtained. This results show a great potential for use in novel crystallization for decently uniform polycrystalline Si thin film transistors (poly-Si TFTs).

• Korean Journal of Materials Research
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• v.17 no.4
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• pp.207-214
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• 2007

We fabricated thermally-evaporated 10 -Ni/(poly)Si and 10 -Ni/1 -Ir/(poly)Si structures to investigate the microstructure of nickel monosilicide at the elevated temperatures required for annealing. Silicides underwent rapid at the temperatures of 300-1200 for 40 seconds. Silicides suitable for the salicide process formed on top of both the single crystal silicon actives and the polycrystalline silicon gates. A four-point tester was used to investigate the sheet resistances. A transmission electron microscope(TEM) and an Auger depth profile scope were employed for the determination of vertical section structure and thickness. Nickel silicides with iridium on single crystal silicon actives and polycrystalline silicon gates shoed low resistance up to 1000 and 800, respectively, while the conventional nickle monosilicide showed low resistance below 700. Through TEM analysis, we confirmed that a uniform, 20 -thick silicide layer formed on the single-crystal silicon substrate for the Ir-inserted case while a non-uniform, agglomerated layer was observed for the conventional nickel silicide. On the polycrystalline silicon substrate, we confirmed that the conventional nickel silicide showed a unique silicon-silicide mixing at the high silicidation temperature of 1000. Auger depth profile analysis also supports the presence of thismixed microstructure. Our result implies that our newly proposed iridium-added NiSi process may widen the thermal process window for the salicide process and be suitable for nano-thick silicides.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.4
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• pp.308-317
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• 2007

We fabricated thermally-evaporated 10 nm-Ni/(poly)Si and 10 nm-$Ni_{0.5}Co_{0.5}$/(Poly)Si structures to investigate the microstructure of nickel silicides at the elevated temperatures required lot annealing. Silicides underwent rapid annealing at the temperatures of $600{\sim}1100^{\circ}C$ for 40 seconds. Silicides suitable for the salicide process formed on top of both the single crystal silicon actives and the polycrystalline silicon gates. A four-point tester was used to investigate the sheet resistances. A transmission electron microscope and an Auger depth profilescope were employed for the determination of vortical microstructure and thickness. Nickel silicides with cobalt on single crystal silicon actives and polycrystalline silicon gates showed low resistance up to $1100^{\circ}C$ and $900^{\circ}C$, respectively, while the conventional nickle monosilicide showed low resistance below $700^{\circ}C$. Through TEM analysis, we confirmed that a uniform, $10{\sim}15 nm$-thick silicide layer formed on the single-crystal silicon substrate for the Co-alloyed case while a non-uniform, agglomerated layer was observed for the conventional nickel silicide. On the polycrystalline silicon substrate, we confirmed that the conventional nickel silicide showed a unique silicon-silicide mixing at the high silicidation temperature of $1000^{\circ}C$. Auger depth profile analysis also supports the presence of this mixed microstructure. Our result implies that our newly proposed NiCo-alloy composite silicide process may widen the thermal process window for the salicide process and be suitable for nano-thick silicides.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.129-134
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• 2004

The development of fabrication processes of polycrystalline-silicon-thin-film transistors (poly-Si TFTs) at low temperatures is reviewed. Rapid crystallization through laser-induced melt-regrowth has an advantage of formation of crystalline silicon films at a low thermal budget. Solid phase crystallization techniques have also been improved for low temperature processing. Passivation of $SiO_2$/Si interface and grain boundaries is important to achieve high carrier transport properties. Oxygen plasma and $H_2O$ vapor heat treatments are proposed for effective reduction of the density of defect states. TFTs with high performance is reported.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.459-462
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• 2007

An electric field was applied to a conductive layer to induce Joule heating in order to carry out the crystallization of amorphous silicon. Polycrystalline silicon was produced through a solid state transformation within the range of a millisecond. Uniformly distributed grains were obtained due to enormously high heating rate.

• Analytical Science and Technology
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• v.26 no.1
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• pp.27-33
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• 2013

Polyalkylsilanes such as poly(dialkyl)silanes and poly(monoalkyl)silanes were synthesized by sonochemical dechlorination-condensation method from (dialkyl or monoalkyl)chlorosilanes with sodium metal. Those polyalkylsilanes were analyzed for the properties such as thermal behaviors from TGA analysis and obtained ceramic yields of 10-20% for poly(dialkyl)silanes and 40-60% for poly(monoalkyl)silanes. Ceramic composite discs were prepared by the combined mixture of polyalkylsilanes and SiC powder and were tested by TGA and analyzed by SEM and XRD for the application as binder for ceramic composite precursors.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.129-130
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• 2008

Polycrystalline silicon (poly-Si) Schottky barrier thin film transistors (SB-TFT) are fabricated by erbium silicided source/drain for n-type SB-TFT. High quality poly-Si film were obtained by crystallizing the amorphous Si film with excimer laser annealing (ELA) or solid phase crystallization (SPC) method. The fabricated poly-Si SB-TFTs have a large on/off current ratio with a low leakage current. Moreover, the electrical characteristics of poly-Si SB TFTs are significantly improved by the additional forming gas annealing in 2 % $H_2/N_2$, because the interface trap states at the poly-Si grain boundaries and at the gate oxide/poly-Si channel decreased.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1993.11a
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• pp.55-59
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• 1993

In this study, we developed new process for doping poly-Si film. Sb(antimony) thin film was used as doping source. Sb was evaporated on poly-Si film deposited by LPCVD fallowed by annealing. We investigate sheet resistance variation with annealing temperature and time. Finally we adapted this process to poly-Si TFT fabrication.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1131-1134
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• 2003

A low temperature doping technique has been studied for application in poly-Si TFT's on plastic substrates. Heavily-doped amorphous silicon layers were deposited on poly-Si and the dopant atoms were driven in by subsequent excimer laser annealing. The entire process was carried out under a substrate temperature of $120^{\circ}C$, and a sheet resistance as low as $300 {\Omega}/sq$. was obtained.

• Korean Journal of Metals and Materials
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• v.46 no.2
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• pp.88-96
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• 2008

Thermal evaporated 10 nm-$Ni_{50}Co_{50}$/(70 nm-poly)Si films were deposited to examine the energy saving properties of silicides formed by rapid thermal annealing at temperature ranging from 500 to $1,100^{\circ}C$ for 40 seconds. Thermal evaporated 10 nm-Ni/(70 nm-poly)Si films were also deposited as a reference using the same method for depositing the 10 nm-$Ni_{50}Co_{50}$/(70 nm-poly)Si films. A four-point probe was used to examine the sheet resistance. Transmission electron microscopy (TEM) and X-ray diffraction XRD were used to determine cross sectional microstructure and phase changes, respectively. UV-VIS-NIR and FT-IR (Fourier transform infrared spectroscopy) were used to examine the near-infrared (NIR) and middle-infrared (MIR) absorbance. TEM analysis confirmed that the uniform nickel-cobalt composite silicide layers approximately 21 to 55 nm in thickness had formed on the single and polycrystalline silicon substrates as well as on the 25 to 100 nm thick nickel silicide layers. In particular, nickel-cobalt composite silicides showed a low sheet resistance, even after rapid annealing at $1,100^{\circ}C$. Nickel-cobalt composite silicide and nickel silicide films on the single silicon substrates showed similar absorbance in the near-IR region, while those on the polycrystalline silicon substrates showed excellent absorbance until the 1,750 nm region. Silicides on polycrystalline substrates showed high absorbance in the middle IR region. Nickel-cobalt composite silicides on the poly-Si substrates annealed at $1,000^{\circ}C$ superior IR absorption on both NIR and MIR region. These results suggest that the newly proposed $Ni_{50}Co_{50}$ composite silicides may be suitable for applications of IR absorption coatings.