• Current Photovoltaic Research
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• v.10 no.3
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• pp.84-89
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• 2022

c-Si solar cells currently account for more than 90% of the solar energy market. Research on tandem junction solar cells to overcome efficiency limitations is drawing attention at a time when new technologies are being developed to secure the price competitiveness of silicon solar cells. Among several candidate materials for silicon-based tandem solar cells, perovskite has recently been studied as it is suitable for the ease of process as well as for its properties as a tandem solar cell material. In this study, we want to review the research trends and technology limitations of 2-T Perovskite/SHJ tandem junction solar cells.

• Vacuum Magazine
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• v.1 no.4
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• pp.4-9
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• 2014

About 170 years has been passed since the concept of photovoltaic has been suggested by French physicist Alexandre-Edmond Becquerel. Now the highest efficiency of solar cell has reached up to 44% by III-V multi-junction solar cells with concentrator. Those multi-junction solar cells are suitable as energy source for spaceships. On the other hand, the cell efficiency of solar cell for electric power generation as energy source for Earth has is going to be saturated although commercial solar cell efficiency is around 20%. In the part 1 of this article, the history of III-V multi-junction solar cells which have been adapted for spaceships is explained and in the part 2, new approach for the improvement of cell efficiency is suggested as the energy source for Earth.

• Journal of Electrical Engineering and information Science
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• v.2 no.5
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• pp.65-71
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• 1997

We present heterojunction solar cells with a structure of metal/a-Si:H(n-i-p)/poly-Si(n-p)/metal for the terrestrial applications. This cell consists fo two component cells: a top n-i-p junction a-Si:Hi cell with wide-bandgap 1.8eV and a bottom n-p junction poly-Si cell with narrow-bandgap 1.1eV. The efficiency influencing factors of the solar cell were investigated in terms of simulation an experiment. Three main topics of the investigated study were the bottom cell with n-p junction poly-Si, the top a-Si:H cell with n-i-p junction, and the interface layer effects of heterojunction cell. The efficiency of bottom cell was improved with a pretreatment temperature of 900$^{\circ}C$, surface polishing, emitter thickness of 0.43$\mu\textrm{m}$, top Yb metal, and grid finger shading of 7% coverage. The process optimized cell showed a conversion efficiency about 16%. Top cell was grown by suing a photo-CVD system which gave an ion damage free and good p/i-a-Si:H layer interface. The heterojunction interface effect was examined with three different surface states; a chemical passivation, thermal oxide passivation, and Yb metal. the oxide passivated cell exhibited the higher photocurrent generation and better spectral response.

• 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.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.894-897
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• 2006

Spatial distribution of injected electrons and holes is evaluated by using single-junction charge pumping technique in SONOS(Poly-silicon/Oxide/Nitride/Oxide/Silicon) memory cells. Injected electron are limited to length of ONO(Oxide/Nitride/oxide) region in locally ONO stacked cell, while are spread widely along with channel in fully ONO stacked cell. Hot-holes are trapped into the oxide as well as the ONO stack in locally ONO stacked cell.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.346-346
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• 2009

For high efficiency hetero junction solar cell over 20%, good silicon wafer passivation is one of the most important technological factor. Compared to the conventional PECVD technique, HWCVD has appeared as an promising alternative for high quality passivation layer formation. In this work, HWCVD passivation layer characteristics have been intensively investigated on wafer surface treatment, Hydrogen density in deposited thin layer and thermal effects in deposition process. Comprehensive results of the individual process factors on interface passivation has been discussed and resultant silicon hetero junction solar cell characteristics has been investigated.

• Journal of computational fluids engineering
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• v.14 no.1
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• pp.35-44
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• 2009

To adequately analyze flows in pipe or duct network system, traditional node-based junction coupling methods require the junction loss which is specified by empirical or analytic correlations. In this paper, a new finite volume junction coupling method using a ghost junction cell is developed by considering the interchange of linear momentum as well as the important wall-effect at junction without requiring any correlation on the junction loss. Also, boundary treatment is modified to preserve the stagnation enthalpy across boundaries, such as pipe-end and the interface between junction and branch. Also, the computational accuracy and efficiency of the Godunov-type finite volume schemes are investigated by tracing the total mechanical energy of rapid transients due to sudden closure of valve at downstream end.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.5
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• pp.290-294
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• 2018

The shingled photovoltaic module can be produced by joining divided solar cells into a string of busbarless structure and arranging them in series and parallel to produce a module, in order to produce a high output per unit area. This paper reports a study to optimize solar cell electrode structure for shingled photovoltaic module fabrication. The characteristics of each electrode structure were analyzed according to the simulation program as follow: 80.62% fill factor in the six-junction solar cell electrode structure and 19.23% efficiency in the five-junction electrode structure. Therefore, the split electrode structure optimized for high-density and high-output shingled module fabrication is the five-junction solar cell electrode structure.

• Journal of the Semiconductor & Display Technology
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• v.14 no.4
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• pp.45-49
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• 2015

Using a combined CVD and ALD equipment system, multi-layer quantum well structures of $Al_2O_3/a-Si/Al_2O_3$ were fabricated on silicon Schottky junction devices and implemented to quantum well solar cells, in which the 1~1.5 nm thicknesses of the aluminum oxide films and the a-Si thin film layers were deposited at $300^{\circ}C$ and $450^{\circ}C$, respectively. Fabricated solar cell was operated by tunneling phenomena through the inserted quantum well structure being generated electrons on the silicon surface. Efficiency of the fabricated solar cell inserted with multi-quantum well of 41 layers has been increased by about 10 times that of the solar cell of pure Schottky junction solar cell.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.11a
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• pp.393-398
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• 2000

In this paper, we propose an Intelligent Monitoring Network System(IMNS) for the truck scale balance system. Truck scale balance system consis of three parts; Load cell part, Indicator part, and Junction box part. IMNS is attached to Junction box in truck scale balance system. Even if Load cell have been some problems, a truck scale balance system still has been run to determine, the values involved error. Therefore prosed system is has concentrated on Load cell part. Other Parts have been changed a portion of circuit for monitoring system.