• 한국결정성장학회지
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• 제23권3호
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• pp.119-123
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• 2013

Most of the world's solar cells in photovoltaic industry are currently fabricated using crystalline silicon. Czochralski-grown silicon crystals are more expensive than multicrystalline silicon crystals. The future of solar-grade Czochralski-grown silicon crystals crucially depends on whether it is usable for the mass-production of high-efficiency solar cells or not. It is generally believed that the main obstacle for making solar-grade Czochralski-grown silicon crystals a perfect high-efficiency solar cell material is presently light-induced degradation problem. In this work, the substitution of boron with gallium in p-type silicon single crystal is studied as an alternative to reduce the extent of lifetime degradation. The diamond-wire sawing technology is employed to slice the silicon ingot. In this paper, the quality of the diamond wire-sawn gallium-doped silicon wafers is studied from the chemical, electrical and structural points of view. It is found that the characteristic of gallium-doped silicon wafers including texturing behavior and surface metallic impurities are same as that of conventional boron-doped Czochralski crystals.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.167-169
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• 2002

Selective, highly stable determination of serotonin was achieved in cyclic voltammetric measurement carried out at electrochemically treated conductive boron-doped diamond electrode. Boron-doped diamond electrodes were prepared on single crystal Si wafers by microwave plasma chemical vapor deposition and $B_2O_3$ was dissolved in acetone/methanol(9:1) mixture solution so that the B/C weight ratio ca. $10^4ppm$. Serotonin is a kind of indoleamines, which secreted from adrenal marrow cells. The serious problem to detection of serotonin is the interference phenomena of electroactive constituent, including AA. In this study, electrochemical treatment of HDD was carried out to discriminate between serotonin and AA responses. Experimental results showed that the peak potential of AA oxidation shift to the positive direction and the oxidation peak of serotonin was unchanged.

• Journal of Electrochemical Science and Technology
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• 제14권3호
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• pp.215-221
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• 2023

A rapid and environment-friendly electrochemical sensor to determine the chemical oxygen demand (COD) has been developed. The boron-doped diamond (BDD) thin-film electrode is employed as the anode, which fully oxidizes organic pollutants and provides a current response in proportion to the COD values of the sample solution. The BDD-based amperometric COD sensor is optimized in terms of the applied potential and the solution pH. At the optimized conditions, the COD sensor exhibits a linear range of 0 to 80 mg/L and the detection limit of 1.1 mg/L. Using a set of model organic compounds, the electrochemical COD sensor is compared with the conventional dichromate COD method. The result shows an excellent correlation between the two methods.

• 한국진공학회지
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• 제9권2호
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• pp.110-115
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• 2000

열-필라멘트 CVD 장치를 이용하여 다이아몬드 박막의 증착 조건을 최적화시켰다. $B_4C $ 고체 펠렛을 사용하여 보론두핑된 다이아몬드 박막을 제조하여 그 질적 특성을 알아보고, 전류전압 특성과 전계 방출 측정을 통해 박막의 전계방출소자(field emission display (FED)로의 특성을 조사하였다. 보론 도핑의 양이 증가함에 따라 다이아몬드 결정의 평균 입자 크기가 조금씩 감소하지만 다이아몬드의 질은 소량 도핑인 경우에 크게 바뀌지 않았다. Al/Diamond/p-Si 소자의 전류전압 특성을 조사한 결과 도핑된 다이아몬드 박막의 전류는 도핑되지 않은 박막의 전류에 비해 $10^4$~$10^5$배 정도 증가하였다. 전계방출 특성을 조사한 결과 보론-도핑이 증가함에 따라 점차 낮은 전기장에서 전자를 방출하며, 또한 높은 방출 전류를 나타냈다. 전자가 방출되기 시작하는 onset-field는 펠렛의 수가 2개일 때 15.5 V/$\mu\textrm{m}$, 3개일 때 13.6 V/$\mu\textrm{m}$, 4개일 때는 11.1 V/$\mu\textrm{m}$. 체계적으로 감소하였다. 도핑의 강도가 세어짐에 따라 Fowler-Nordheim 그래프의 기울기는 감소하는 경향을 보였으며, 이로서 보론 도핑으로 인해 유효 장벽 에너지가 감소되어 전자 방출 특성이 향상됨을 알 수 있었다.

• 한국표면공학회지
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• 제57권1호
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• pp.1-7
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• 2024

The study investigated the impact of substrate pretreatment on depositing high-quality B-doped diamond (BDD) thin films using the HFCVD method. Films were deposited on Si and Nb substrates after sanding and seeding. Despite identical sanding conditions, BDD films formed faster on Nb due to even diamond seed distribution. Post-deposition, film average roughness (R_a) remained similar to substrate R_a, but higher substrate R_a led to decreased crystallinity. Nb substrate with 0.83 ㎛ R_a exhibited faster crystal growth due to dense, evenly distributed diamond seeds. BDD film on Nb with 0.83 ㎛ R_a showed a wide, stable potential window (2.8 eV) in CV results and a prominent 1332 cm^-1 diamond peak in R_aman spectroscopy, indicating high quality. The findings underscore the critical role of substrate pretreatment in achieving high-quality BDD film fabrication, crucial for applications demanding robust p-type semiconductors with superior electrical properties.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2274-2278
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• 2012

To test the efficiency of the BDD electrode for complete mineralization of organic wastewater, phenol and 2-chlorophenol (2-CP) were treated electrochemically with both an active Pt/Ti electrode and a nonactive boron doped diamond (BDD) electrode, respectively, in neutral aqueous medium. Aqueous solutions of both phenol and 2-chlorophenol were treated electrochemically using an in-house fabricated flow through electrochemical cell (FTEC). The experimental variables included current input, treatment time, and the flow rate of the solutions. Depending on the magnitude of the applied current and reaction time, the compounds were either completely degraded or partially oxidized to other intermediates. Removal efficiencies reached as high as 93.2% and 94.8% both at the Pt/Ti electrode and BDD electrode, respectively, at an applied current of 200 mA for a 3.0 hr reaction and a flow rate of 4 mL/min. The BDD electrode was much more efficient for the complete mineralization of phenol and 2-chlorophenol than the Pt/Ti electrode.

• 한국환경과학회지
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• 제32권6호
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• pp.465-475
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• 2023

In this study, we evaluated the treatment efficiency of livestock wastewater by altering the current density using boron-doped diamond (BDD) electrodes. As the current density was adjusted from 10 to 35 mA/cm2, the removal efficiency of organic matter increased from 22.2 to 71.5%. Similar to that of organic matter, the removal efficiency of color increased with increasing current density up to 85.7%, indicating a higher removal efficiency for color than that of organic matter. The removal efficiency of ammonia nitrogen increased from 14.6 to 53.3% as the current density increased, but it was lower than that of organic matter. In addition, the removal of organic matter, color, and ammonia nitrogen followed first-order reactions, according to the reaction rate analysis. The energy consumption ranged from 4.87 to 8.33 kWh/kg COD, and it was found that the organic matter removal efficiency was more efficient at high current densities. Based on various analyses, the optimal current density was 20 mA/cm2, and the corresponding energy consumption was 6.824 kWh/kg COD.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2008년도 High Temperature Superconductivity Vol.XVIII
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• pp.13-13
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• 2008

• 한국표면공학회지
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• 제32권3호
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• pp.244-248
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• 1999

Photoelectrodeposition of copper on semiconductive B-doped diamond films was investigated. There are cleasr morphology differences between photodeposited copper and electrodeposited copper. Photoelecrodeposition proceeded as uniform 2-dimensional growth. On the other hand electrodeposition proceeded as scarce random deposition. By applying this effect we have succeeded in forming a conductive pattern on semiconductive B-doped diamond with the aid of a photo-mask. And it was suggested that the surface reforming caused by photoelectrochemical process could be easily detected by the following metal (copper) deosition method, which is demonstrated as 'Diamond photographic phenomenon'.

• 전기화학회지
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• 제3권4호
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• pp.200-203
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• 2000

Microwave plasma chemical vapor deposition을 이용하여 붕소가 도핑된 전도성 다이아몬드 박막을 제조하였다. 탄소원으로는 아세톤과 메탄올을 사용하였으며, 붕소원으로는 $B_2O_3$를 사용하고, 운반가스로는 수소를 사용하였다. 이때 붕소의 도핑농도는 약 $10^2ppm\;(B/C)$이였다. Si 기질 각 부분의 온도와 플라즈마에서의 거리를 다르게 하기 위해서 Si 기질을 배치함에 있어 약$10^{\circ}$를 기울여 다이아몬드 박막을 성장시켰다. 실험결과 모두 동일한 조건 이였으나 같은 Si 기질 위에 높이에 따른 온도구배가 형성되었으며, 그에 따라 다이아몬드의 결정 또한 각기 달랐다. 다이아몬드 박막에 나타난 결정형태의 분포는 약 $3\~4$부분으로 나뉘어 있었다 제조된 다이아몬드 박막의 특성을 확인하기 위해 Raman spectrum을 이용해 다이아몬드의 결정성을 확인하였고, 표면의 형태를 관찰하기 위해 현미경을 사용하였다. 입자의 크기는 각기 다른 Si기질의 높이에 의한 온도구배로 인하여, 기질의 높이에 따라 서서히 달라졌다. 다이아몬드 박막의 Raman spectrum측정결과 $1334cm^{-1}$에서 강한 peak가 발견되었으며, 이것은 결정성 다이아몬드의 일반적인 특성 이였다. Si 기질 중 낮은 곳에 위치한 부분의 Raman spectrum은 비다이아몬드의 peak인 $1550cm^{-1}$ 부근에서 넓게 peak가 상승된 것이 관찰되었다.