• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.318-321
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• 2002

This paper presents a proper condition to achieve high conversion efficiency using PC1D simulator on sri-crystalline Si solar cells. Various efficiency influencing parameters such as rear surface recombination velocity and minority carrier diffusion length in the base region, front surface recombination velocity, junction depth and doping concentration in the Emitter layer, BSF thickness and doping concentration were investigated. Optimized cell parameters were given as rear surface recombination of 1000 cm/s, minority carrier diffusion length in the base region 200 $\mu\textrm{m}$, front surface recombination velocity 100 cm/s, sheet resistivity of emitter layer 100 Ω/$\square$, BSF thickness 5 $\mu\textrm{m}$, doping concentration 5${\times}$10$\^$19/ cm$\^$-3/. Among the investigated variables, we learn that a diffusion length of base layer acts as a key factor to achieve conversion efficiency higher than 19 %.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.553-556
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• 1999

This paper presents a proper condition to achieve above 19 % conversion efficiency using PC1D simulator. Cast poly-Si wafers with resistivity of 1 $\Omega$-cm and thickness of 250 ${\mu}{\textrm}{m}$ were used as a starting material. Various efficiency influencing parameters such as rear surface recombination velocity and minority carrier diffusion length in the base region, front surface recombination velocity, junction depth and doping concentration in the Emitter layer, BSF thickness and doping concentration were investigated. Optimized cell parameters were given as rear surface recombination of 1000 cm/s, minority carrier diffusion length in the base region 200 ${\mu}{\textrm}{m}$, front surface recombination velocity 100 cnt/s, sheet resistivity of emitter layer 100 $\Omega$/$\square$, BSF thickness 5 ${\mu}{\textrm}{m}$, doping concentration 5$\times$10$^{19}$ cm$^3$ . Among the investigated variables, we learn that a diffusion length of base layer acts as a key factor to achieve conversion efficiency higher than 19 %. Further details of simulation parameters and their effects to cell characteristics are discussed in this paper.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.50.1-50.1
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• 2010

결정질 실리콘 태양전지의 원가에서 Wafer는 60~70%의 매우 높은 비중을 차지하고 있다. 많은 연구들이 원가 절감을 위하여 Wafer의 두께를 감소시키는 것에 집중하고 있다. 그러나 Wafer 두께의 감소는 태양전지의 효율 감소와 공정 진행 중에 파손율이 상승하는 등의 문제가 발생한다. 이에 본 논문에서는 결정질 태양전지 구조 중에서 24.7% 이상의 최고 변환 효율을 갖는 PERL(Passivated Emitter, Rear Locally diffuse) 구조를 대상으로 wafer 두께 감소에 따른 변환 효율 감소의 원인과 해결 방안을 제시하고자 한다. Simulation으로 확인한 결과 370 um 두께의 wafer에서 24.2 %의 효율은 50 um 두께의 wafer에서는 20.8 %로 감소함을 확인할 수 있었다. 얇아진 wafer에서 감소한 효율을 개선하기 위하여 후면 recombination velocity, 후면 fixed charge density, 후면 산화막 두께 등을 다양화하여, 각각의 경우에 대한 cell의 효율 변화를 살펴보았다. 그 결과 후면 recombination velocity, 후면 fixed charge density, 후면 산화막 두께를 최적화 하여, 각각 2.8 %p, 1.5 %p, 2.8 %p의 효율 개선 효과를 얻었다. 위 세 가지 효과를 동시에 적용하면 50 um wafer에서 370 um wafer 효율의 결과와 근접한 24.2 %의 효율을 얻을 수 있었다. 향후에는 위의 결과를 바탕으로 실제 실험을 통하여 확인할 계획이다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.43.1-43.1
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• 2010

In the crystalline silicon solar cells, the full area aluminum_back surface field(BSF) is routinely achieved through the screen-printing of aluminum paste and rapid firing. It is widely used in the industrial solar cell because of the simple and cost-effective process to suppress the overall recombination at the back surface. However, it still has limitations such as the relatively higher recombination rate and the low-to-moderate reflectance. In addition, it is difficult to apply it to thinner substrate due to wafer bowing. In the recent years, the dielectric back-passivated cell with local back contacts has been developed and implemented to overcome its disadvantages. Although it is successful to gain a lower value of surface recombination velocity(SRV), the series resistance($R_{series}$) becomes even more important than the conventional solar cell. That is, it is a trade off relationship between the SRV and the $R_{series}$ as a function of the contact size, the contact spacing and the geometry of the opening. Therefore it is essential to find the best compromise between them for the high efficiency solar cell. We have investigated the optimal design for the local back contact by using PC1D simulation.

• 대한전기학회논문지
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• 제33권4호
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• pp.157-163
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• 1984

The object of this paper is to investigte the gate controlled diode structure for ionic concentration measurement. It includes device fabrication, characterization, device physics and modeling of the gate controlled diode structure. The differences of turn on voltages and surface generation currents in the (100) and (111) silicon crystallographic orientation of the sample device were observed. Therefore the dependence of these two factors of the silicon crystallographic orientation was investigated. It was observed that drifts arose after extended immersion of the sample device in acid or base solutions. The surface generation-recombination velocity of both (100) and (111) increased. The increase in the interfacial traps for both surface, determined by the turn on voltage was directly proportional to the surface generation-recombination velocity increase.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 춘계학술대회
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• pp.702-705
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• 2011

고효율 다결정 태양전지 제작의 방향을 제시하기 위해 PC1D 프로그램을 이용하여 전, 후면 재결합 속도, 소수 캐리어 확산거리, 접합깊이, 에미터 층 면저항, 후면 전계층이 미치는 영향을 조사하였다. 최적화된 전지 파라미터는 후면 재결합 속도 1000 cm/sec, 베이스 층에서의 소수 캐리어 확산거리 50 [${\mu}m$], 전면 재결합 속도 100 [cm/sec], 에미터 층 면저항 $100{\Omega}/\Box$, 후면 전계층 두께 및 도핑 농도는 각각 0.5 [${\mu}m$]와 $5{\times}10^{19}\;cm^{-3}$로 조사되었다. 특히 19.8% 이상의 변환효율을 얻기 위해서는 베이스층의 확산거리가 가장 중요한 파라미터임을 알 수 있었다.

• Nuclear Engineering and Technology
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• 제54권12호
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• pp.4620-4624
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• 2022

Several cadmium zinc telluride (CZT) crystals were fabricated into radiation detectors using methods that included slicing, dicing, lapping, polishing, and chemical etching. A wet passivation with sodium hypochlorite (NaOCl) was then carried out on the Br-etched detectors. The Te-rich layer on the CZT surface was successfully compensated to the Te oxide layer, which was analyzed with X-ray photoelectron spectroscopy data of both a Br-etched crystal and a passivated CZT crystals. We confirmed that passivation with NaOCl improved the transport property by analyzing the mobility-lifetime product and surface recombination velocity. The electrical and spectroscopic properties of large volume detectors were compared before and after passivation, and then the detectors were observed for a month. Both bar and quasi-hemispherical detectors show an enhancement in performance after passivation. Thus, we could identify the effect of NaOCl passivation on large volume CZT detectors.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.256-256
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• 2009

This paper presents a proper condition to achieve above 17 % conversion efficiency using PC1D simulator. Crystalline silicon wafer with thickness of $240{\mu}m$ was used as a starting material. Various efficiency influencing parameters such as rear surface recombination velocity and minority carrier diffusion length in the base region, front surface recombination velocity, junction depth and doping concentration in the Emitter layer. Among the investigated variables, we learn that 2nd doping concentration as a key factor to achieve conversion efficiency higher than 17 %.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권4호
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• pp.187-191
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• 2004

In this work, we used the PCID simulator for simulation of solar cell and examined the effect of front-back surface recombination velocity, minority carrier diffusion length, junction depth and emitter sheet-resistance. As the effect of base thickness, the efficiency decreased by the increase in series resistance with the increase of the thickness and found decrease in efficiency by decrease of the current as the effect of the recombination. Also, as the effect of base resistivity, the efficiency increased somewhat with the decrease in resistivity, but when the resistivity exceeded certain value, the efficiency decreased as a increase in the recombination ratio. The optimum efficiency was obtained at the resistivity 0.5 $\Omega$-cm, and thickness $100\mu\textrm{m}$. We have successfully achieved 10.8% and 13.7% efficiency large area($103mm{\times}103mm$) mono-crystalline silicon solar cells without and with PECVD silicon nitride antireflection coating.

• 마이크로전자및패키징학회지
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• 제22권4호
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• pp.111-115
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• 2015

실리콘 태양전지의 효율을 향상하기 위해서는 소수 캐리어의 높은 수명이 필수조건이다. 따라서, 이를 달성하기 위한 실리콘 표면결함을 없애줄 수 있는 부동화(passivation) 기술이 매우 중요하다. 일반적으로 PECVD 법이나 열산화 공정을 통해 얻어진 $SiO_2$ 박막이 부동화 층으로 많이 사용되나 1000도에 이르는 고온 공정과 낮은 열적 안정성이 문제로 여겨진다. 본 연구에서는 원자층 증착법을 이용하여 400도 미만의 저온 공정을 통해 $Al_2O_3$ 부동화 박막을 형성하였다. $Al_2O_3$ 박막은 고유의 음의 고정 전하밀도로 인해 낮은 표면 재결합속도를 보이는 것으로 알려져 있다. 본 연구에서는 질소 도핑을 통해 높은 음의 고정 전하 밀도를 얻고 이를 통해 좀 더 향상된 실리콘 표면 부동화 특성을 얻고자 하였다.