• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.18 no.7
• /
• pp.662-666
• /
• 2005

Silicon nitride $(SiN_x)$ film is a promising material for anti-reflection coating and passivation of multicrystalline silicon (me-Si) solar cells. In this work, a plasma-enhanced chemical vapor deposition (PECVD) system with batch-type reactor tube was used to prepare highly robust $SiN_x$ films for screen-printed mc-Si solar cells. The Gas flow ratio, $R=[SiH_4]/[NH_3]$, in a mixture of silane and ammonia was varied in the range of 0.0910.235 while maintaining the total flow rate of the process gases to 4,200 sccm. The refractive index of the $SiN_x$ film deposited with a gas flow ratio of 0.091 was measured to be 2.03 and increased to 2.37 as the gas flow ratio increased to 0.235. The highest efficiency of the cell was $14.99\%$ when the flow rate of $SiH_4$ was 350 sccm (R=0.091). Generally, we observed that the efficiency of the mc-Si solar cell decreased with increasing R. From the analysis of the reflectance and the quantum efficiency of the cell, the decrease in the efficiency was shown to originate mainly from an increase in the surface reflectance for a high flow rate of $SiH_4$ during the deposition of $SiN_x$ films.

• New & Renewable Energy
• /
• v.5 no.3
• /
• pp.26-31
• /
• 2009

Using MBE growth method, GaAs/AlGaAs solar cell structure was grown. Deposited electrodes are Au/Ni/Ge for n-type and Au/Pt/Ti for p-type electrodes were deposited by E-beam evaporator. Indoor light concentrators were devised and fabricated in order to concentrate artificial solar rays. Also mirror and prism and Fresnel lens concentration system with solar simulator were devised and fabricated. Results of solar cell characteristics were measured with shutting system which can control the amount of light. Maximum power density was 2.13 W/$cm^2$ and maximum concentration was 124 sun, when mirror with Fresnel lens was used at $7854\;mm^2$ of shutter hole.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.02a
• /
• pp.393-393
• /
• 2011

오늘 날 태양전지 산업에서 가장 많은 생산을 하고 있는 분야는 결정질 태양전지분야이다. 현재는 이러한 시대적 요구에 따라 많은 연구가 진행되고 있는데 특히 junction을 이루는 n layer의 doping profile을 선택적으로 형성하여 개방전압 및 단락전류를 향상시키는 연구가 활발히 진행되고 있다. 본 연구는 이러한 n type layer의 doping profile을 선택적으로 형성하는 selective emitter solar cell에 관한 연구로써 SILVACO simulation을 이용하여 low Rs 영역은 고정하고 high Rs 영역의 doping depth를 가변 함으로써 high Rs 영역을 달리 형성하는 방법으로 selective emitter solar cell의 high Rs영역의 최적화에 관한 전산모사를 실시하였다. 각각의 가변조건에 따라 quantum efficiency를 통한 광학적 분석과 I-V를 통한 전기적 분석을 하여 high Rs영역을 최적화 하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.18 no.5
• /
• pp.179-183
• /
• 2008

Employing screen printing technology, aluminum is applied to the back side of the n-type silicon wafer to see the effect of the heat treatment parameters on the Voc of the solar cell, Heat treatment at $850^{\circ}C$ produces the highest Voc among various heat treatment conditions. Heat treatment at the temperatures higher than $850^{\circ}C$ results in lower Voc, which is due to the destruction of the Al-Si alloy emitter layer. The destruction of Al-Si layer observed to be caused by the vigorous movement of silicon atoms toward aluminum layer during the heat treatment.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2010.05a
• /
• pp.30.2-30.2
• /
• 2010

Nano-scale p-n junction can generate various nano-scale functional devices such as nanowire light emitting diode, nanowire solar cell, and nanowire sensor. The core shell type nanowire p-n junction has been considered for the high efficient devices in many previous reports. On the other hand, although device efficiency is relatively lower, the cross bar type p-n junction has simple topological structure, suggested by C.M. Lieber group, to integrate easily many p-n junction devices in one board. In this study, for the integration of the cross bar nanowire p-n junction device, a simple fabrication route, employed dielectrophoretic array and direct printing techniques, was demonstrated by the successful fabrication and programmable integration of the nanowire cross bar p-n junction solar cell. This direct printing process will give the single nanowire solar cell the opportunity of the integration on the circuit board with other nanowire functional devices.

• Current Photovoltaic Research
• /
• v.2 no.4
• /
• pp.147-151
• /
• 2014

A boron doping process using a boron tri-bromide ($BBr_3$) as a boron source was applied to form a $p^+$ emitter layer on an n-type mono-crystalline CZ substrate. Nitrogen ($N_2$) gas as an additive of the diffusion process was varied in order to study the variations in sheet resistance and the uniformity of doped layer. The flow rate of $N_2$ gas flow was changed in the range 3 slm~10 slm. The sheet resistance uniformity however was found to be variable with the variation of the $N_2$ flow rate. The optimal flow rate for $N_2$ gas was found to be 4 slm, resulting in a sheet resistance value of $50{\Omega}/sq$ and having a uniformity of less than 10%. The process temperature was also varied in order to study its influence on the sheet resistance and minority carrier lifetimes. A higher lifetime value of $1727.72{\mu}s$ was achieved for the emitter having $51.74{\Omega}/sq$ sheet resistances. The thickness of the boron rich layer (BRL) was found to increase with the increase in the process temperature and a decrease in the sheet resistance was observed with the increase in the process temperature. Furthermore, a passivated emitter solar cell (PESC) type solar cell structure comprised of a boron doped emitter and phosphorus doped back surface field (BSF) having Ni/Cu contacts yielding 15.32% efficiency is fabricated.

• Current Photovoltaic Research
• /
• v.1 no.1
• /
• pp.17-26
• /
• 2013

In contrast to conventional crystalline cells, back-contact solar cells feature high efficiencies, simpler module assembly, and better aesthetics. The highest commercialized cell and module efficiency was recorded by n-type back-contact solar cells. However, the mainstream PV industry uses a p-type substrate instead of n-type due to the high costs and complexity of the manufacturing processes in the case of the latter. P-type back-contact solar cells such as metal wrap-through and emitter wrap-through, which are inexpensive and compatible with the current PV industry, have consequently been developed. In this paper the characteristics of EWT (emitter wrap-through) solar cells and their status and prospects for development are discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.448-449
• /
• 2008

HIT(Heterojunction with intrinsic thin layer) solar cell은 결정 실리콘 (c-Si)을 n-type으로 제작시 수율이 어렵고 결정 실리콘 (c-Si)을 p-type위에 제조하는 것이 보다 보편적인 방법이므로 베이스의 결정 실리콘에는 p-type을, 그 위에는 진성 층(intrinsic layer) 그리고 반투명 전극의 아래에 제조되는 비정질 실리콘 (a-Si)을 n-type으로 하여 베이스 층과 TCO 후면 층의 두께, 도핑 농도 (doping concentration)와의 관계를 확인하여 본다.

• Nuclear Engineering and Technology
• /
• v.8 no.1
• /
• pp.29-40
• /
• 1976

An investigation on the effect of electrostatic drift field which can bring an additional aid to the photogenerated carrier collection in one side of the silicon solar cell has been carried out. The drift field was produced by the gradient of boron concentration in the p-type side in virtue of the strain compensation due to the tin dopant. A new method of ion implantation which is based on the principle of chiefly radiation-enhanced diffusion is adopted for forming the p-n junction in the solar cell. The open circuit voltage and the conversion efficiency of the ion-implanted silicon solar cell sample can be figured out to be 0.44 V and 5%, respectively.

• Journal of the Semiconductor & Display Technology
• /
• v.19 no.2
• /
• pp.55-59
• /
• 2020

Copper Oxide (CuO) films were deposited on the n-type silicon wafer by rf magnetron sputtering for heterojunction solar cells. And then the samples were treated as a function of the annealing temperature (300-600℃) in a vacuum. Their electrical, optical and structural properties of the fabricated heterojunction solar cells were then investigated and the power conversion efficiencies (PCE) of the fabricated p-type copper oxide/n-type Si heterojunction cells were measured using solar simulator. After being treated at temperature of 500℃, the solar cells with CuO film have PCE of 0.43%, Current density of 5.37mA/㎠, Fill Factor of 39.82%.