• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.9
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• pp.438-443
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• 2001

In the shallow trench isolation(STI)-chemical mechanical polishing(CMP) process, the key issues are the optimized thickness control, within-wafer-non-uniformity, and the possible defects such as pad oxide damage and nitride residue. The defect like nitride residue and silicon (or pad oxide) damage after STI-CMP process were discussed to accomplish its optimum process condition. To understand its optimum process condition, overall STI related processes including reverse moat etch, trench etch, STI fill and STI-CMP were discussed. Consequently, we could conclude that law trench depth and high CMP thickness can cause nitride residue, and high trench depth and over-polishing can cause silicon damage.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.3
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• pp.276-283
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• 1994

The dislocation configuration in web-grown silicon ribbon was investigated using chemical etching techniques. The presence of dislocation loops on twin planes is observed and acounted for by self-interstitial condensation. The interstitials were either quenched in, due to the rapid cooling of the ribbon from the solidification temperatures, or produced by oxide precipitation on the twin plane. Very large faulted loops of mm size were also observed.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.3
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• pp.294-301
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• 1988

A study on the lattice damages and impurity depth profiles have been performed with BF2 ion implanted silicon materials. Electrical measurement, SIMS and TEM analysis techniques were used in order to identify the reverse annealing phenomena, impurity depth profiles and lattice damages. A typical reverse annealing phenomena were shown at the dose of 1x10**15/cm\ulcorner and non-reverse annealing at the dose of 5x10**15/cm\ulcorner This was explained with the formation of the amorphous region at BF2+ ion implantation with high dose. That is, the amorphous reigons were recrystallized centrated at certain regions were measured by SIMS technique. The dislocation loops-like crystalline defects were observed with TEM cross sections, which were formed at the lattice damaged region during annealing process.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.743-746
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• 2000

Plastic microlenses play an important role in reducing the size, weight, and the cost of the systems in the fields of optical data storage and optical communication. In the present study, plastic microlens arrays were fabricated using micro-compression molding process. The design and fabrication procedures for mold insert were simplified by using silicon instead of metal. A simple but effective micro compression molding process, which uses polymer powder, were developed for microlens fabrication. The governing process parameters were temperature and pressure histories and the micromolding process was controlled such that the various defects developing during molding process were minimized. The radius and magnification ratio of the fabricated microlens were $125{\mu}m$ and over 3.0, respectively.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.8
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• pp.1242-1245
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• 2001

Plastic microlenses play an important role in reducing the size, weight, and the cost of the systems in the fields of optical data storage and optical communication. In the present study, plastic microlens arrays were fabricated using micro-compression molding process. The design and fabrication procedures for mold insert were simplified by using silicon instead of metal. A simple but effective micro compression molding process, which uses polymer powder, were developed for microlens fabrication. The governing process parameters were temperature and pressure histories and the micromolding process was controlled such that the various defects developing during molding process were minimized. The radius and magnification ratio of the fabricated microlens were 125$\mu\textrm{m}$ and over 3.0, respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.1
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• pp.38-44
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• 2008

Contiuous c-oriented zeolite MFI films $(<35{\mu}m)$ were prepared by hydrothermal secondary growth of silicalite-1 seed crystal in the surface of alumina porous substrate and silicon substrate. The supported films were characterized with scanning electron microscopy and X-ray diffraction. Effect of substrate surface roughness were investigated and a mechanism for c-oriented film formation and characteristic dom-like defects formation which is observed after seeding growth was discussed. The roughness of substrate plays an important role.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.1
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• pp.117-123
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• 2014

The fabrication and characterization of a Si/ZnO thin film heterojunction ultraviolet photodiode has been presented in this paper. ZnO thin film of ~100 nm thick was deposited on <100> Silicon (Si) wafer by atomic layer deposition (ALD) technique. The Photoluminescence spectroscopy confirms that as-deposited ZnO thin film has excellent visible-blind UV response with almost no defects in the visible region. The room temperature current-voltage characteristics of the n-ZnO thin film/p-Si photodiodes are measured under an UV illumination of $650{\mu}W$ at 365 nm in the applied voltage range of ${\pm}2V$. The current-voltage characteristics demonstrate an excellent UV photoresponse of the device in its reverse bias operation with a contrast ratio of ~ 1115 and responsivity of ~0.075 A/W at 2 V reverse bias voltage.

• Journal of the Korean Vacuum Society
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• v.5 no.1
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• pp.73-76
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• 1996

We have prepared hydrogenated amophous silicon (a-si : H) films with superlattice structure by hydrogen radical anneling(HRA) technique. We have studied the preparation of a-Si :H films by HRA and the optical & electronic characteristics. Optical band gap and the hydrogen contents in the a Si : H film is decreased as HRA time increased. We first report a -Si : H film prepared by periodicdeposition of a-Si : H layer and HRA have the superlattice structure using TEM . After 1 hour light soaking on the a-Si :H film prepared by HRA, there are no difference in the temperatre dependence of dark conductivity and the conductivity activation energy. An excellent stability for light in a-Si :H films by HRA can be explained using the long-range structural relaxation of the amorphous network and the propertiesof light -induced defects(LID) proposed by Fritzsche.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.429-432
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• 1987

A new LOCOS (Local Oxidation of Silicon) process using a thin nitride film directly deposited on the silicon substrate by LPCVD has been developed in order to reduce the bird's beak length. SEM studies showed that nitride thickness of 50nm can decrease the bird's beak length down to 0.2um with 450nm field oxide. No crystalline defects are observed around the bird's beak after the Wright etch. A 30% improvement in current density was obtained when this new method was applied to MOS transistors (W/L*2.9/20.4) compared to conventional LOCOS process (bird's beak length=0.7um). Other various electrical parameters improved by this new simple LOCOS process are reported in this paper.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.2
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• pp.226-235
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• 2016

The yield of 3D stacked IC manufacturing improves with the pre-bond integrity testing of through silicon vias (TSVs). In this paper, an efficient pre-bond test method is presented based on IEEE std. 1500, which can precisely diagnose any happening of TSV defects. The IEEE std. 1500 wrapper cells are augmented for the proposed method. The pre-bond TSV test can be performed by adjusting the driving strength of TSV drivers and the test clock frequency. The experimental results show the advantages of the proposed approach.