• Title/Summary/Keyword: $POCl_3$

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First Principles Study on Hydrolysis of Hazardous Chemicals PCl3 and POCl3 Catalyzed by Water Molecules (제일원리 계산을 통한 유해화학물질 PCl3와 POCl3의 물분자 촉진 수화반응 연구)

  • Jeong, Hyeon-Uk;Gang, Jun-Hui;Jeon, Ho-Je;Han, Byeong-Chan
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2017.05a
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    • pp.126-126
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    • 2017
  • Using first principles calculations we unveil fundamental mechanism of hydrolysis reactions of two hazardous chemicals $PCl_3$ and $POCl_3$ with molecular water clusters nearby. It is found that the water molecules play a key role as a catalyst significantly lowing the activation barriers by transferring its protons to the reaction intermediates. Interestingly, torsional angles of molecular complexes at transition states are identified as a vital descriptor on the reaction rate. Analysis of charge distribution over the complexes further reinforces the finding with atomic level correlation between the torsional angle and variation of the orbital hybridization state of P in the complex. Electronic charge separation (or polarization) enhances thermodynamic stability of the activated complex at transition state and reduces the activation energy through hydrogen bonding network with water molecules nearby. Calculated potential energy surfaces (PES) for the hydrolysis reactions of $PCl_3$ and $POCl_3$ depict their two contrastingly different profiles of double- and triple-deep wells, respectively. It is ascribed to the unique double-bonding O=P in the $POCl_3$. Our results on the activation free energy show well agreements with previous experimental data within $7kcalmol^{-1}$ deviation.

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Characteristics of Polysilicon Resistors with High Thermal Stability Fabricated by POCl$_{3}$ Doping and Arsenic Implantation (POCl$_{3}$ 도핑 및 비소 이온주입공정으로 제작한 높은 안정성을 갖는 다결정실리콘 저항소자 특성)

  • 이대우;노태문;구진근;남기수
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.35D no.7
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    • pp.56-62
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    • 1998
  • Polysilicon resistors with high thermal stability have been fabricated by a new mixed process using POCl$_{3}$ doping and arsenic implantation. Varous temeprature coefficients, which range form 510 ppm/.deg. C to -302 ppm/.deg. C, were shown from the fabricated polysilicon resistors with sheet resistance of 58~107 .ohm./sq in the operating temeprature of 27~150.deg. C. The temperature coefficient of the polysilicon resistor by the mixed technology was about 4.3 times as low compared to the conventional polysilicon resistor using POCl$_{3}$ doped single process with the same sheet resistance of 75.ohm./sq. In addition, the mixed technology can be applied to obtain nearly zero temperature coefficient for polysilicon resistors which are reliable and insensitive to temperature.

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Study on the pn Junction Device Using the POCl3 Precursor (POCl3를 사용한 pn접합 소자에 관한 연구)

  • Oh, Teresa
    • Journal of the Korean Vacuum Society
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    • v.19 no.5
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    • pp.391-396
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    • 2010
  • The pn junction for solar cell was prepared on p-type Si wafer by the furnace using the $POCl_3$ and oxygen mixed precursor to research the characteristic of interface at pn junction. The sheet resistance was decreased in accordance with the increasing the diffusion process time for n-type doping on p-type Si wafer. The electron affinity at the interface in the pn junction was decreased with increasing the amount of n-type doping and the sheet resistance also decreased. Consequently, the drift current due to the generation of EHP increased because of low potential barrier. The efficiency and fill factor were increased at the solar cell with increasing the diffusion process time.

Modification of Nonwoven Poly(vinyl alcohol) Fabrics (I) - Reaction of Water Soluble Poly(vinyl alcohol) Nonwoven Fabrics with Phosphoryl Chloride - (폴리비닐알콜 부직포의 개질에 관한 연구 (I) - 수용성 폴리비닐알콜 부직포와 POCl3의 반응 특성 -)

  • Lee, Won-Chul;Kim, Chang-Sup;Jang, Sang-Hee;Song, Du-Hyun;Lyoo, Won-Seok;Gal, Yeong-Soon
    • Textile Coloration and Finishing
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    • v.20 no.6
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    • pp.75-81
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    • 2008
  • This paper dealt with the synthesis and characterization of the polymeric product by the reaction of the water-soluble poly(vinyl alcohol)[PVA] nonwoven fabrics and the phosphoryl chloride ($POCl_3$), which has been applied to prepare water-proofing materials or intermediates for increasing water-proofing or fire-proofing ability of commercially available water-soluble PVA support layer. $POCl_3$ was reacted with PVA nonwoven fabrics under non-aqueous condition, and their reactivity, and chemical structure were checked and discussed. PVA was reacted with $POCl_3$ under the reaction condition of 1:1, or 1:2 mole ratios at 70, 80 and $90^{\circ}C$, and the reaction products were further hydrolyzed. The structure of the resulting products from water soluble PVA nonwoven fabrics reacted with $POCl_3$ were identified by FT-IR or X-ray fluorescence spectrophotometer, and they indicated the PVA polymer chains to have phosphorous and chlorine moieties.

Spectrophotometric Determination of Traces of Phosphorus in Semiconductor-grade Trichlorosilane (반도체급 삼염화실란 중의 극미량 인의 분광광도법적 정량)

  • Dong Kwon Kim;Myoung Wan Han;Hee Young Kim
    • Journal of the Korean Chemical Society
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    • v.36 no.2
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    • pp.255-260
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    • 1992
  • A procedure for spectrophotometric determination of traces of phosphorus(P) in high-purity trichlorosilane(TCS) is proposed using an adsorptive separation. $PCl_3$, which is a dominant P impurity within TCS, is first oxidized by oxygen to a stable form as $POCl_3$. $AlCl_3$ is selected as an adsorbent which forms a thermally stable complex with $POCl_3$ in TCS and can be well dissolved in aqueous ethanol solution. The proposed adsorptive separation method is free from the formation of silica gel and gas bubbles during the colorimetric analysis of TCS. The method reveals that the P concentration in a semiconductor-grade TCS is 5.32 ${\mi}g/l$ within the standard deviation of ${\pm}$ 17%. On the other hand, the P concentration of the purified TCS which is separated from the $AlCl_3$${\cdot}$$POCl_3$ complex is reduced to be less than 0.15 ${\mi}g/l$, showing the efficient applicability of $AlCl_3$ to the wet chemical analysis. The proposed method is also tested to verify the effectiveness of other well-known adsorbents.

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에미터층의 최적화를 위한 온도와 시간에 따른 면저항 특성분석

  • Kim, Hyeon-Yeop;Choe, Jae-U;Lee, Jun-Sin
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.401-401
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    • 2011
  • 태양전지 제작에 있어서 에미터층의 최적화를 위해 POCl 도핑시 에미터층의 면저항 가변에 중요한 파라미터인 온도와 가스비를 변화하여 실험을 진행하였다. 본 실험에 사용될 최초 기판은 두께가 200${\pm}$5 ${\mu}m$, 비저항이 0.5~0.3 ${\Omega}{\cdot}cm$의 P-type(100) 실리콘 기판을 사용하였으며 먼저 POCl3양과 deposition 시간 그리고 산소와 질소의 양을 고정시키고 온도에 따른 에미터 면저항 변화를 알아보았다. 온도는 830, 840, 850, 860, 870, 880$^{\circ}C$로 가변시켰으며 공정온도가 높아질수록 면저항 값이 낮아짐을 알 수 있었다. 균일도는 낮은 온도에서는 다소 좋지 않았지만 온도가 높아질수록 점차 좋아졌으며 870$^{\circ}C$ 이상에서는 거의 균일한 값을 얻을 수 있었다. 한편, 이번에는 공정온도를 고정하고 산소와 POCl3 가스량의 변화에 따른 면저항 특성과 균일도를 알아보았다. 가스비와 압력 그리고 위치별 면저항 특성에 대해서 알아보았고 부분압이 증가함으로 반응로 내의 O2의 양이 증가함을 알 수 있었다. 증가한 O2는 도핑과정에서 산화막을 더 두껍게 형성하게 하며 높은 면저항 값을 가져오게 하였다. 즉, 충분한 가스량의 주입으로 도핑시 균일도를 향상시킬 수 있었다. 이와 같이 부분압이 증가함에 따라 면저항의 증가와 균일도의 향상을 가져왔다.

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Optimization of the $POCI_3$ doping process according to the variation of deposition temperature, gas flow rate and doping time (온도, 가스량 및 도핑시간변화에 따른 $POCI_3$ 도핑 공정의 최적화)

  • 정경화;강정진
    • Electrical & Electronic Materials
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    • v.7 no.3
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    • pp.206-212
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    • 1994
  • In this paper, We discuss the $POCI_3$ doping process according to the variation of deposition temperature, gas flow rate and doping time. The factors acted with $POCI_3$ doping are gas flow rate deposition temperature and time etc. Among them the temperature is the most important factor. For the $POCI_3$ flow rate, it should not exceed the resistivity saturation point developed on poly surface by annealing treatment. Therefore, this study suggests the optimum conditions of Poly-silicon treatments with the $POCI_3$ flow rate.

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Study on separation process of tri-cresyl phosphate by reaction of $POCl_3$ with mixed cresol (혼성 Cresol과 $POCl_3$의 반응에 의한 tri-Cresyl Phosphate의 분리공정 연구)

  • 김장규;원성호;양승남;이상석;김남기
    • Journal of the Korean Society of Safety
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    • v.13 no.2
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    • pp.109-115
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    • 1998
  • Tri-cresyl phosphate(TCP) was synthesized by reaction of phosphorus chloride with mixed cresol(mixture of m-cresol, p-cresol, and others) in the presence of $AlCl_3$. Some of unwanted products and unreactants colored TCP. In order to separate TCP from these, vaccume distillation was carried twice, but colorless TCP could not be producted. Separation of unwanted materials by 2% NaOH solution was introduced before first and second distillation and optimal separation conditions such as NaOH concentration, mixing volume ratio, mixing time, and rpm were investigated for new batch separation and production of colorless TCP Optimal conditions were 2% NaOH solution, 35% mixing volume ratio of 2% NaOH solution, 1.5 hours of mixing time, and 20 rpm.

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Physicochemical Properties of Cross-linked Rice Starches (가교화 쌀 전분의 이화학적 특성)

  • Choi, Hyun-Wook;Chung, Koo-Min;Kim, Chung-Ho;Moon, Tae-Hwa;Park, Cheon-Seok;Baik, Moo-Yeol
    • Applied Biological Chemistry
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    • v.49 no.1
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    • pp.49-54
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    • 2006
  • Physicochemical properties of cross-linked rice starches were investigated. Swelling power of cross-linked rice starch increased at relatively lower temperature $(60^{\circ}C)$ than native rice starch $(70^{\circ}C)$. Cross-linked rice starch showed lower solubility $(1.7{\sim}6.1%)$ than native rice starch $(2.2{\sim}13.8%)$ and solubility is not significantly different with the amount of phosphorus oxychloride. Pasting temperature $(69.2{\sim}70.6^{\circ}C)$ and peak viscosity $(2,874{\sim}3,175\;cp)$ of cross-linked rice starch were lower than native starch $(71.6^{\circ}C,\;3,976\;cp)$, but holding strength $(2,177{\sim}2,708\;cp)$ and final viscosity $(3,424{\sim}3,826 \;cp)$ of cross-linked rice starch were higher than native starch (1,000 cp, 2,312 cp). DSC thermal transitions of cross-linked rice starches were shifted to a lower temperature than native rice starch but there was no significant difference in gelatinization enthalpy between native and cross-linked rice starches. X-ray diffraction pattern of both native and cross-linked rice starches showed typical A-type crystal indicating that cross-linking had not affected the crystalline region of starch.