• Korean Journal of Crystallography
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• v.11 no.4
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• pp.207-211
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• 2000

In a Czochralski silicon single crystal, the relation between the growth twin and the crystal morphology was investigated. The growth twin is nucleated on the {111} facet planes near the growth ridges. When a {111} growth twin is formed in the <100> silicon crystal, the growth ridge where twin is nucleated will continuous through the twin plane. Other two ridges at the 90。 apart will be displaced about 33° and be deformed to facets. The ridge on the opposite side of twin nucleation will disappear by forming a slight hill. Because the growth ridges of silicon is due to the {111} planes, the variation in the growth ridge formation can be predicted clearly by considering the change of the {111} plane traces in the stereographic projection after twining.

• Journal of the Korea Society of Computer and Information
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• v.8 no.2
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• pp.57-63
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• 2003

In this paper, we propose the hardware architecture of a scale converter which is to convert a variety range of scale into a target scale and a time sequential color control driver for LOCS (Liquid Crystal On Silicon) micro display devices which are considered advanced micro display technology in the next generation. The driver has been implemented and tested with ASIC chips.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.299-306
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• 1998

Crystallization of the amorphous silicon needs activation. Thermal energy through laser annealing, furnace annealing and rapid thermal process (RTP) has been convinced to crystallize the amorphous silicon thin film. It is expected that some other type of energy like mechanical energy can help to crystallize the amorphous silicon thin film. In this study, mechanical energy through wet blasting of silica slurry and silicon ion implantation has been applied to the amorphous silicon thin film deposited with LPCVD technique. RTP was employed for the annealing of this mechanically-damaged amorphous silicon thin film. For the characterization of the crystallized silicon thin film, XRD and Raman analysis were conducted. In this study, it is shown that the mechanical damage is effective to enhance the crystallization of amorphous silicon thin film.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.3 no.2
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• pp.117-124
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• 1993

It was found that the basic principle of continuous crystal growth method was following as; the powder supplied from the feeding system is molten in the graphite crucible under the ambient gas. After forming the molten zone in the lower part of the crucible, the seed crystal is deeped into the melt and pulled down with the rotation so that the melt crystallized from the seed. When the lowering rate, rotation rate, feeding rate and temperature are correct, the single crystal can grow. The critical melt level, the feeding rate, the growth rate, the change of the shape of molten zone by the graphite susceptor and crucible, the position of work coil, the balance between the gravitational force of melt and the centrifugal force originated from the rotation of seed which are the variables of the crystal growth and the sintering phenomenon of melt surface were researched.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.4
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• pp.336-346
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• 1994

We studied the reaction between silicon and carbon. Silicon granules and silicon with 0.2 wt% carbon powders were prepared for sample and then they were heated up to the $1450^{\circ}C, 1550^{\circ}C, 1650^{\circ}C, 1700^{\circ}C$ and were dwelled 1 hr and 4 hrs, respectively. we studied the change of morphologies of molten silicon and the formation of SiC following the reaction withcarbon using optical microscope, SEM, and XRD. Above the melting point of silicon, oxygens are precipitated during the decomposition of quartz used crucible. SiO formed from the reaction between molten silicon and precipitated oxygen evaporated and made the surface defects. SiC were formed with the reaction between the unreacted carbon and molten silicon. Polytype of the SiC formed at the solidification interface was ${\alpha}-SiC$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.1
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• pp.11-18
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• 1996

Grown-in defects like OISF and FPD in the large diameter(> 8 inch)of silicon crystal are characterized. It was revealed that the presence of the ring-patterned OISF would deterorate the minority life time of the silicon crystal. Through the cooling experiment from the $1250^{\circ}C$, the nucleation of the OISF was confirmed to follow the homogeneous nucleation and growth process. In addition to OISF nucleus, crystal originated particle, which was known to be closely related with FPD (Flow Pattern Defects), was found to depend on the pulling rate of the crystal. Combination of the lower rate of the pulling and the faster cooling near the $950^{\circ}C$ is proposed to be effective method in reducing the generation of these grown-in defects.

• Transactions of Materials Processing
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• v.12 no.7
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• pp.623-630
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• 2003

Nanomachining process, static nanoplowing, is one of the most promising lithographic technologies in terms of the low cost of operation and variety of workable materials. In nanomachining process, chemical effects are more dominant factor compared with those by physical deformation or fracture. For example, during the nanoscratch on a silicon surface in the atmosphere, micro protuberances are formed due to the mechanochemical reaction between diamond tip and the surfaces. On the contrary, in case of chemically stable materials, such as ceramic or glass, surface protuberances are not formed. The purpose of this study is to understand effects of the mechanochemical reaction between tip and surfaces on deformation behaviors of hard-brittle materials. Nanometerscale elasoplastic deformation behavior of single crystal silicon (100) was characterized with micro protuberance phenomena, and compared with that of borosilicate (Pyrex glass 7740). In addition, effects of the silicon protuberances on nanoscratch test results were discussed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.449-455
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• 1997

The anisotropic etching behavior of single crystal silicon were studied in aqueous KOH solution. N-type (100) oriented single crystal silicon wafers were used for the study, and the $SiO_2$ layer, whose etching rate is known to be much slower than that of silicon in the KOH solution, was used as a mask for the silicon etching. The silicon etching rate and the etching properties are shown to be a function of etchant temperature uniformity, circulation speed, and circulation direction of the etchant as well as the etchant concentration and the temperature. The etching rate is increased as the temperature is increased from $10\mu \textrm{m}/hr$ to $250\mu \textrm{m}/hr$ in the range of $50^{\circ}C~105^{\circ}C$. Hillock density and height is observed to be correlated with the etchant concentration and the etch temperature. The variation of the hillock density was explained by the ratio between the etching rate of (100) orientation and that of (111) orientation.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.5
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• pp.191-194
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• 2008

We will focus on the horizontal Bridgman growth system to analyze the transport phenomena numerically, because the simple furnace system and the confined growth environment allow for the precise understanding of the transport phenomena in solidification process. In conventional melt growth process, the dopant concentration tends to vary significantly along the crystal. In this work, we propose the modification of crucible geometry for improving the productivity of silicon single-crystal growth by controlling axial specific resistivity distribution. Numerical analysis has been performed to study the transport phenomena of dopant impurities in conventional and proposed Bridgman silicon growth using the finite element method and implicit Euler time integration. It has been demonstrated using mathematical models and by numerical analysis that proposed method is useful for obtaining crystals with superior uniformity along the growth direction at a lower cost than can be obtained by the conventional melt growth process.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.3 no.2
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• pp.149-156
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• 1993

Polycrystalline silicon was produced from metallurgical-grade Si by unidirectional solidification. Variations of impurity concentration and resistivity in the ingots have been investigated. X-ray diffraction analysis has also been performed to examine the crystal orientation. According to the X-ray diffraction analysis on the polycrystalline silicon, preferential orientation was changed from ( 220) into ( III ) with decreasing growth rate. Also, with increasing growth rate and fraction solidified, the resistivity tends to decrease.