• Journal of the Korean Ceramic Society
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• v.31 no.1
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• pp.74-78
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• 1994

Degradation of thin oxide by doped poly-Si and its improvement were studied. The gate oxide can be degraded by phosphorous in poly-Si doped POCl3. The degradation is increased with the decrement of sheet resistance and poly-Si thickness. Oxide failures of amorphous-Si are higher than those of poly-Si. In-situ double deposition of amorphous-Si, 54$0^{\circ}C$/30 nm, and poly-Si, 6$25^{\circ}C$/220 nm, forms the mismatch structure of grain boundary between amorphous-Si and poly-Si, and suppresses the excess phosphorous on oxide surface by the mismatch structure. The control of phosphorous through grain boundary improves the oxide reliability.

• Proceedings of the KAIS Fall Conference
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• 2010.05a
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• pp.153-155
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• 2010

실리콘 태양전지의 pn 접합 계면특성을 조사하기 위해서 p형 실리콘 기판 위에 전기로를 이용한 $POCl_3$ 공정을 통하여 n형의 불순물을 주입하여 pn접합을 만들었다. n형 불순물의 확산되어 들어가는 공정시간이 길고 공정온도가 높을수록 면저항은 줄어들었다. n형 불순물의 주입이 많아질수록 pn 접합 계면에서의 전자친화도가 줄어들면서 면저항은 감소되었다고 할 수 있다. n형 반도체의 페르미레벨이 높아지면서 공핍층도 생기지만 n형 불순물이 많아지면서 공핍층의 폭은 점점 좁아지고 쇼키 장벽의 높이도 낮아지면서 자유전자와 홀 쌍의 이동이 쉽게 이루어지게 되었다. n형의 불순물 확산공정시간이 긴 태양전지 셀에서 F.F. 계수가 높게 나타났으며, 효율도 높게 나타났다.

• Polymer(Korea)
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• v.30 no.3
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• pp.266-270
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• 2006

Poly [(dimethylmethylyinyl) siloxane] phosphineoxide (PMViSPO) was prepared by adding phosphorus oxychloride $(POCl_3)$ to poly (dimethylmethylyinyl) siloxane (PMViS) at $0^{\circ}C$ under nitrogen atmosphere. Cadmium selenide (CdSe) was prepared by reacting cadmium oxide (CdO), tetradecyl-phosphonic acid (TDPA), trioctylphosphine oxide (TOPO) at $300^{\circ}C$, and adding solution of dissolved Se to tributylphosphine (TBP) and trioctylphosphine (TOP) CdSe-poly [(dimethylmethylvinyl) siloxane] phosphine-oxide (CdSe-SPO) adduct was synthesised by adding PMViSPO to CdSe solution. Liquid silicone rubber composite (LSRC-1) was prepared by compounding $\alpha,\omega-vinyl$ poly (dimethylsiloxane) (VPMS), $\alpha,\omega-hydrogen$) poly(dimethylsiloxane) (HPMS), and CdSe under Pt catalyst, and also LSRC-2 was prepared from VPMS, HPMS, and CdSe-SPO using Pt catalyst. It was confirmed that CdSe nanoparticles with photoluminescence characteristics was dispersed uniformly in LSR matrix. The diameter of CdSe was $30\sim50nm$. By measuring the number of CdSe nanoparticles, 202 particles of CdSe in LSRC-2 and 165 particles of CdSe in LSRC-1 were dispersed in the same area of LSR matrix. Thermal stability for LSRC-2 compounded with CdSe-SPO was better than LSRC-1.

• Solar Energy
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• v.17 no.4
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• pp.3-11
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• 1997

Because grain boundaries in polycrystalline silicon act as potential barriers and recombination centers for the photo-generated charge carriers, these defects degrade conversion effiency of solar cell. To reduce these effects of grain boundaries, we investigated various influencing factors such as thermal treatment, various grid pattern, selective wet etching for grain boundaries, buried contact metallization along grain boundaries, grid on metallic thin film. Pretreatment above $900^{\circ}C$ in $N_2$ atmosphere, gettering by $POCl_3$ and Al treatment for back surface field contributed to obtain a high quality poly-Si. To prevent carrier losses at the grain boundaries, we carried out surface treatment using Schimmel etchant. This etchant delineated grain boundaries of $10{\mu}m$ depth as well as surface texturing effect. A metal AI diffusion into grain boundaries on rear side reduced back surface recombination effects at grain boundaries. A combination of fine grid with finger spacing of 0.4mm and buried electrode along grain boundaries improved short circuit current density of solar cell. A ultra-thin Chromium layer of 20nm with transmittance of 80% reduced series resistance. This paper focused on the grain boundary effect for terrestrial applications of solar cells with low cost, large area, and high efficiency.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3609-3617
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• 2014

A series of compounds containing both 1,3,4-oxadiazole and thiohydantoin were synthesized as a promising scaffold for application in medicinal chemistry. The key step of the synthesis is a microwave-assisted cyclization of semicarbazides possessing a thiohydantoin moiety at one of the acyl termini using $POCl_3$ as a dehydrating reagent. A wide range of semicarbazides were prepared through the substitution of hydrazides with an N-acylated thiohydantoin derived from the cyclization of the corresponding isothiocyanate with an amino acid and subsequent N-acylation of the resultant thiohydrantion. Consequently, the 58 number of 1,3,4-oxadiazole derivatives having a thiohydantoin substituent were prepared in good overall yields.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.428-433
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• 2000

The consolidation behavior of multicomponent particles prepared by the flame hydrolysis deposition process is examined to identify the effects of Si substrate temperature. To fabricate multi-component particles, a vapor-phase ternary mixture of $SiCl_4(100 cc/min),\;BCl_3(30cc/min)\;and\;POCl_3,(5cc/min)$ was fed into a coflow diffusion oxy-hydrogen flame burner. The doped silica soot bodies were deposited on silicon substrates under various deposition conditions. The surface temperature of the substrate was measured by an infrared thermometer. Changes in the chemical states of the doped silica soot bodies were examined by FT-IR(Fourier-transformed infrared spectroscopy). The deposited particles on the substrate were heated at $1300^{\circ}C$ for 3h in a furnace at a heating rate of 10K/min. Si-O-B bending peak has been found when surface temperature exceeds $720^{\circ}C$. Correspondingly, the case with substrate temperatures above loot produced good consolidation result.

• Current Photovoltaic Research
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• v.2 no.3
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• pp.130-134
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• 2014

We have fabricated the selective emitter solar cell using double textured nanowires structure. The $40{\times}40mm2$-sized silicon substrates were textured to form the pyramid-shaped surface and the nanowires were fabricated by metal assisted chemical etching process using Ag nanoparticles, subsequently. The heavily doped and shallow emitters for selectiv eemitter solar cells were prepared through the thermal $POCl_3$ diffusion and chemical etch-back process, respectively. The front and rear electrodes were prepared following conventional screen printing method and the widths of fingers have been optimized. The selective emitter solar cell using double textured nanowires structure achieved a conversion efficiency of 17.9% with improved absorption and short circuit current density.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2565-2569
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• 2010

It was researched the correlation between the Solar cell and the effect of texturing. The samples were textured by using the IPA mixed solution with $HNO_3$, KOH and NaOH. The samples were analyzed by the X-ray Diffraction pattern and Fourier Transform Infrared spectroscopy. The FTIR spectra in the range of 950~1350 $cm^{-1}$ was related to the peak's formation as the bonding structure. The split of peaks means that the inter reaction between the molecular did not activate and then increased the efficiency because of low reflectance as shown the cell treated in NaOH mixed solution.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1361-1363
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• 1998

Poly-Si grain boundaries act as potential barriers as well as recombination centers for the photo-generated carriers in solar cells. Thereby, grain boundaries of poly-Si are considered as a major source of the poly-Si cell efficiency was reduced This paper investigated grain boundary effect of poly-Si wafer prior to the solar cell fabrication. By comparing I-V characteristics inner grain, on and across the grain boundary, we were able to detect grain potentials. To reduce grain boundary effect we carried out pretreatment, $POCl_3$ gettering, and examined carrier lifetime. This paper focuses on resistivity variation effect due to grain boundary of poly-Si. The resistivity of the inner grain was $2.2{\Omega}-cm$, on the grain boundary$2.3{\Omega}-cm$, across the grain boundary $2.6{\Omega}-cm$. A measured resistivity varied depending on how many grains were included inside the four point probes. The resistivity increased as the number of grain boundaries increased. Our result can contribute to achieve high conversion efficiency of poly-Si solar cell by overcoming the grain boundary influence.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.233-233
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• 2010

It is important to form the n+ emitter layer for generating electric potential collecting EHP(Electron-Hole Pair). In this paper the formation on the n+ emitter layer of silicon wafer has been made with respect to uniformity of shallow diffusion from a liquid source. The starting material was crystalline silicon wafers of resistivity $0.5{\sim}3\{Omega}{\cdot}cm$, p-type, thickness $200{\mu}m$, direction[100]. The formation of n+ emitter layer from the liquid $POCl_3$ source was carried out for $890^{\circ}C$ in an ambient of $N_2:O_2$::10:1 by volume. And than each conditions are pre-deposition and drive-in time. It has been made uniformity of at least. so, the average of sheet resistance was about 0.12%. In this study, sheet resistance was measured by 4-point prove.