• Journal of the Korean Institute of Telematics and Electronics
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• v.19 no.1
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• pp.9-13
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• 1982

The purpose of this experiment is to evaluate the noise dependency on the gate dimensions of the P-ch MOSFET which is fabricated of p+ sourse, drain, and gate electrode doped with PH$_3$ gas in type-N Si sudstrate. Experimental results indicate that: for the constant gate area and reletively thick films, noise level tends to decrease for the W/L ratio over unity, which generally conforms with theoretical observations, but its variation with the change in the thickness of film is less than the theoretically predicted for the W/L ratio below unity.

• Transactions of Materials Processing
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• v.16 no.1 s.91
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• pp.61-66
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• 2007

Powder injection molding(PIM) is widely used for many parts in the field of automotives, electronics and medical industries, due to the capability of net shaping for complex 3-D geometry. Powder injection mold design for the dental scaler tip, a component of medical appliance, was presented. In comparison with conventional machining process, powder injection molding has many advantages, specially in price and dimensional stability, for molding dental scaler tip which has complex geometry. Both product design and mold design for dental scaler tip were presented. A PIM feedstock was made of stainless series(17-4PH, 316L, 440C) powder and a wax based binder. The 'rapid mold' concept was applied to manufacture the various forms and materials of dental scaler tip including vibration characteristics.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.69-69
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• 1999

고집적 DRAM 소자의 캐패시터 제조 공정에 있어 하부 전극을 고농도로 도핑을 하기 위한 방안의 일환으로 고체 P를 이용한 two-zone 확산법으로 다결정 실리콘에 도핑하는 방법을 채택하고 가능성을 검토하였다. 기존의 도핑방법과는 달리 불필요한 산화막을 형성하지 않고 굴곡진 표면을 따라 균일하게 고농도로 도핑할 수 있는 장점이 있다. 본 실험에서는 단결정 실리콘 및 다결정 실리콘에 대해 온도와 시간을 달리하여 P를 도핑하고, SIMS 분석으로 실험 조건에 따른 표면 농도를 분석하였다. 또한 도핑 온도를 달리하여, PH3를 이용하여 도핑한 경우와 비교 분석하였다. 표면 부근의 고농도 도핑을 위해서는 도핑온도를 저온으로 가져가고 도핑시간을 길게 가져가는 것이 유리하고, 고체 P를 사용한 경우에 있어서 PH3에 비해 표면 부근의 농도가 약 10배 정도 고농도로 도핑된 것을 알 수 있었다. 실제 소자에서의 적용 가능성을 보기 위하여, 캐패시터를 제작하여 전기적 특성을 분석하였다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.3
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• pp.252-256
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• 2009

We have developed low driving voltage white organic light emitting diode with a new electron transport material, triphenylphosphine oxide ($Ph_{3}PO$). The white light emission was realized with a rubrene yellow dopant and blue-emitting DPVBi layer. The new electron transport layer results in a very high current density at low voltage, resulting in a reduction of driving voltage. The device with a new electron transport layer shows a brightness of $1150\;cd/m^2$ at a low driving voltage of 4.3 V.

• Journal of the Korean Chemical Society
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• v.22 no.3
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• pp.117-127
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• 1978

Slater type orbitals, located at two different points A and B, are expressed in a common coordinate system by expanding the spherical harmonics and the radial part of these orbitals in terms of the reference point A. Master formulas for two center overlap integrals are derived, using the general expansion formulas of slater type atomic orbitals. Two center overlap integrals for $CH_4,\;H_2O,\;NH_3,\;C_2H_6\;and\;PH_3$molecules are evaluated, using master formulas for two center overlap integrals. The results are in agreement with those of two center overlap integrals of Mulliken.

• Journal of the Korean institute of surface engineering
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• v.38 no.6
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• pp.216-226
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• 2005

Pb-Free Technology was born with environmental problems of electronic component, Being connected by big and small project of every country. Also, in each country environment is connected and various standards of IEC, ISO, MIL, JIS, KS, JEDEC, EIAJ etc. All products can divide at solder part and finishing part These can tested each and synthetically divide. This research is reliability evaluation for three kind of ph-free SnCu solder plating solution and it's deposit. First, executed analysis about Pure Sn, SnCu solutions and plating surface by way similar to other plating solution analysis. Next, executed reliability about test method and equipment for reliable analyzer system construction. Next, data comparison and estimation, main estimation test method and item's choice. In this paper the systematic surface analysis and reliability for plating solutions and it's deposit in metal surface finishing processes could be shown.

• Journal of the Korean Applied Science and Technology
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• v.12 no.2
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• pp.59-64
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• 1995

Two aromatic polysulfones, poly(PhC-co-SDA)-2 and poly(TPhC-co-SDA)-2, were synthesized by interfacial polycondensation of phthaoyl chloride(PhC) and terephthaloyl chloride(TPhC) with P, P'-sulfonyldianiline(SDA), respectively. The properties of the aromatic polysulfones synthesized were as follows : inherent viscosity, $0.32{\sim}0.35dL/g$:glass transition temperature, $220{\sim}240^{\circ}C$:tensile strength, $308{\sim}336Kg/cm^2$:and 5% weight loss temperature by TGA thermogram in the air, $500{\sim}530^{\circ}C$. As the result, thermal properties of the synthesized copolymers proved to be excellent.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.79-87
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• 2013

An unstable yet efficient phenanthrene-degrading bacterium strain Ph-3 was isolated from a petroleum-contaminated site at the Mathura Oil Refinery, India. The strain was identified as Pseudomonas sp. using a polyphasic approach. An analysis of the intermediates and assays of the degradative enzymes from a crude extract of phenanthrene-grown cells showed a novel and previously unreported pattern of 1, 2-dihydroxy naphthalene and salicylic acid production. While strain Ph-3 lost its phenanthrene- degrading potential during successive transfers on a rich medium, it maintained this trait in oligotrophic soil conditions under the stress of the pollutant and degraded phenanthrene efficiently in soil microcosms. Although the maintenance and in vitro study of unstable phenotypes are difficult and such strains are often missed during isolation, purification, and screening, these bacteria constitute a substantial fraction of the microbial community at contaminated sites and play an important role in pollutant degradation during biostimulation or monitored natural attenuation.

• Proceedings of the KAIS Fall Conference
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• 2008.11a
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• pp.390-393
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• 2008

본 합성법으로 제조된 메조포러스 실리카는 X-선 회절패턴, TEM, FT-IR, BET 측정 결과 MCM-41의 특성과 동일하게 나타났다. 연구 결과 PH조절에 따른 MCM의 특성을 표면적, 기공분포, XRD회절분석, SEM, TEM의 결과를 이용하여 파악하였으며, 쌀겨로부터 규소원을 MCM-41의 합성이 가능함을 알 수 있었다. PH조절에 황산과 아세트산 두 가지의 산을 사용하였다. 그 결과 황산보다는 아세트산을 사용하였을 때 수율과 주기공 크기가 증가하는것을 알수있었다. 아세트산을 이용한 경우 팽윤 효과를 나타내어 주기공 크기가 커진 것이다.

• Korean journal of food and cookery science
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• v.8 no.2
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• pp.73-82
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• 1992

This study investigated conditions necessary for factory production of traditional Korean soy sauce flavors, using Bacillus licheniformis SSA3-2M1. We determined whether the flavors were good or bad by comparing sensory evaluation values and the contents of the main taste components of traditional Korean soy sauce with those of the manufactured soy sauce. The soy broth was cultured by Bacillus licheniformis SSA3-2M1. By providing from 1/3 vvm to 2/3 vvm of air, and a culturing time of 412 hours at 30$^{\circ}C$, we produced the taste of traditional Korean soy sauce; moreover its PH was in the PH range of traditioal Korean soy sauce. The distributions of the main taste components and the amino acids, free sugars, and organic acids in the manufactured soy sauce were similar to tradituioal Korean soy sauce.