• 한국신재생에너지학회:학술대회논문집
• /
• 2006.06a
• /
• pp.228-231
• /
• 2006

This paper briefly introduces silicon based thin film solar cells: amorphous (a-Si:H), microcrystalline ${\mu}c-Si:H$ single junction and $a-Si:H/{\mu}c-Si:H$ tandem solar cells. The major difference of a-Si:H and ${\mu}c-Si:H$ cells comes from electro-optical properties of intrinsic Si-films (active layer) that absorb incident photon and generate electron-hole pairs. The a-Si:H film has energy band-gap (Eg) of 1.7-1.8eV and solar cells incorporating this wide Eg a-Si:H material as active layer commonly give high voltage and low current, when illuminated, compared to ${\mu}c-Si:H$ solar cells that employ low Eg (1.1eV) material. This Eg difference of two materials make possible tandem configuration in order to effectively use incident photon energy. The $a-Si:H/{\mu}c-Si:H$ tandem solar cells, therefore, have a great potential for low cost photovoltaic device by its various advantages such as low material cost by thin-film structure on low cost substrate instead of expensive c-Si wafer and high conversion efficiency by tandem structure. In this paper, the structure, process and operation properties of Si-based thin-film solar cells are discussed.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.12 no.3
• /
• pp.120-125
• /
• 2002

Si-wafers for solar cells were cast in a size of $50{\times}46{\times}0.5{\textrm}{mm}^3$ by vacuum casting method. The graphite mold coated by BN powder, which was to prevent the reaction of carbon with the molten silicon, was used. Without coating, the wetting and reaction of Si melt to graphite mold was very severe. In the case of BN coating, SiC was formed in the shape of tiny islands at the surface of Si wafer by the reaction between Si-melt and carbon of the graphite mold on the high temperature. The grain size was about 1 mm. The efficiency of Si solar cell was lower than that of Si solar cell fabricated on commercial single and poly crystalline Si wafer. The reason of low efficiency was discussed.

• Land and Housing Review
• /
• v.11 no.1
• /
• pp.87-94
• /
• 2020

To implement the planning of zero-energy buildings, their energy performance must be improved, and renewable energy applications must also be included. To accelerate the use of renewable energies in such buildings, BIPVs should be actively used in windows and on roofs. Window-type BIPVs are being developed in various forms depending on the size, composition, area ratio of the window, specification of glass, and so on. To analyze the applicability of various solar cells as window-type BIPVs, in this study, we evaluated their applicability, at the current development level, by analyzing the indoor illuminance, heat gain and heat loss; the cooling, heating, and lighting energy levels; and the generation performance of the various solar cells. To enhance the future applicability of window type BIPV, we analyze the overall energy performance of the building, according to changes in visible light transmittance and generation efficiency. The main research results are as follows. The area ratios above the standard illuminance, based on the window type and according to the VLT, were in order of low-e glazing, a-Si window, DSSC window, and c-Si window. The heat gain of the semi-transparent solar cell winodw was remarkably low. The energy consumption of buildings was highest in the order of c-Si window, DSSC window, a-Si window, and clear low-e window. However, in the case of including the power generation performance of the solar cell, the energy consumption was found to be high in order of DSSC window, c-Si window, a-Si window, and clear low-e window. In the future, if a window-type BIPV is developed, we believe that improvement in power generation performance and improvement in visible light transmittance will be needed.

• Current Photovoltaic Research
• /
• v.6 no.2
• /
• pp.31-38
• /
• 2018

Multijunction solar cells present a practical solution towards a better photovoltaic conversion for a wider spectral range. In this review, we compare different types of multi-ijunction solar cell. First, we introduce thin film multijunction solar cell include to the thin film silicon, III-V material and chalcopyrite material. Until now the maximum reported power conversion efficiencies (PCE) of solar cells having different component sub-cells are 14.0% (thin film silicon), 46% (III-V material), 4.4% (chalcopyrite material) respectively. We then discuss the development of multijunction solar cell in which c-Si is used as bottom sub-cell while III-V material, thin film silicon, chalcopyrite material or perovskite material is used as top sub-cells.

• Journal of the Korean Solar Energy Society
• /
• v.37 no.2
• /
• pp.77-85
• /
• 2017

Thin crystalline silicon (C-Si) solar cell is expected to be a low price energy source by decreasing the consumption of Si. However, thin c-Si solar cell entails the bowing and crack issues in high temperature manufacturing process. Thus, the conventional tabbing process, based on high temperature soldering (> $250^{\circ}C$), has difficulties for applying to thin c-Si solar cell modules. In this paper, a conductive paste (CP) based interconnection process has been proposed to fabricate thin c-Si solar cell modules with high production yield, instead of existing soldering materials. To optimize the process condition for CP based interconnection, we compared the performance and stability of modules fabricated under various lamination temperature (120, 150, and $175^{\circ}C$). The power from CP based module is similar to that with conventional tabbing process, as modules are fabricated. However, the output of CP based module laminated at $120^{\circ}C$ decreases significantly (14.1% for Damp heat and 6.1% for thermal cycle) in harsh condition, while the output drops only in 3% in the samples process at $150^{\circ}C$, $175^{\circ}C$. The peel test indicates that the unstable performance of sample laminated at $120^{\circ}C$ is attributed to weak adhesion strength (1.7 N) between cell and ribbon compared to other cases (2.7 N). As a result, optimized lamination temperature for CP based module process is $150^{\circ}C$, considering stability and energy consumption during the fabrication.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.25 no.3
• /
• pp.236-240
• /
• 2012

Limiting thermal exposure time using rapid thermal processing(RTP) has emerged as promising simplified process for manufacturing of solar cell in a continuous way. This paper reports the simplification of co-firing using RTP. Actual temperature profile for co-firing after screen printing is a key issue for high-quality metal-semiconductor contact. The plateau time during the firing process were varied at $450^{\circ}C$ for 10~16 sec. Glass frit in Ag paste etch anti-reflection layer with plateau time. Glass frit in Ag paste is important for the Ag/Si contact formation and performances of crystalline Si solar cell. We achieved 17.14% efficiency with optimum conditions.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.10
• /
• pp.2909-2912
• /
• 2010

Hydrogenated microcrystalline silicon (${\mu}c$-Si:H) thin film for solar cells is prepared by plasma-enhanced chemical vapor deposition and physical properties of the ${\mu}c$-Si:H p-layer has been investigated. With respect to stable efficiency, this film is expected to surpass the performance of conventional amorphous silicon based solar cells and very soon be a close competitor to other thin film photovoltaic materials. Silicon in various structural forms has a direct effect on the efficiency of solar cell devices with different electron mobility and photon conversion. A Raman microscope is adopted to study the degree of crystallinity of Si film by analyzing the integrated intensity peaks at 480, 510 and $520\;cm^{-1}$, which corresponds to the amorphous phase (a-Si:H), microcrystalline (${\mu}c$-Si:H) and large crystals (c-Si), respectively. The crystal volume fraction is calculated from the ratio of the crystalline and the amorphous phase. The results are compared with high-resolution transmission electron microscopy (HR-TEM) for the determination of crystallinity factor. Optical properties such as refractive index, extinction coefficient, and band gap are studied with reflectance spectra.

• Solar Energy
• /
• v.11 no.3
• /
• pp.74-83
• /
• 1991

In this study, the (p)ZnTe/(n)Si solar cell and (n)CdS-(p)ZnTe/(n)Si poly-junction thin film are fabricated by vaccum deposition method at the substrate temperature of $200{\pm}1^{\circ}C$ and then their electrical properties are investigated and compared each other. The test results from the (p)ZnTe/(n)Si solar cell the (n)CdS-(p)ZnTe/(n)Si poly-junction thin fiim under the irradiation of solar energy $100[mW/cm^2]$ are as follows; Short circuit current$[mA/cm^2]$ (p)ZnTe/(n)Si:28 (n)CdS-(p)ZnTe/(n)Si:6.5 Open circuit voltage[mV] (p)ZnTe/(n)Si:450 (n)CdS-(p)ZnTe/(n)Si:250 Fill factor (p)ZnTe/(n)Si:0.65 (n)CdS-(p)ZnTe/(n)Si:0.27 Efficiency[%] (p)ZnTe/(n)Si:8.19 (n)CdS-(p)ZnTe/(n)Si:2.3 The thin film characteristics can be improved by annealing. But the (p)ZnTe/(n)Si solar cell are deteriorated at temperatures above $470^{\circ}C$ for annealing time longer than 15[min] and the (n)CdS-(p)ZnTe/(n)Si thin film are deteriorated at temperature about $580^{\circ}C$ for longer than 15[min]. It is found that the sheet resistance decreases with the increase of annealing temperature.

• Proceedings of the KIEE Conference
• /
• 2002.07b
• /
• pp.1325-1327
• /
• 2002

$ITO_{(n)}/Si_{(p)}$ solar cell was fabricated by vaccum deposition method under the resistance heating with substrate temperature kept about 200[$^{\circ}C$] and than their properties are investigated. The cell charateristics can be improved by annealing but are deteriorated at temperature above 650[$^{\circ}C$] for longer than 15[min].

• Korean Journal of Materials Research
• /
• v.9 no.12
• /
• pp.1155-1159
• /
• 1999

Thin film solar cells on a glass/$SnO_2$ substrate with p-SiC/i-Si/n-Si heterojunction structures were fabricated using a plasma-enhanced chemical-vapor deposition system. The photovoltaic properties of the solar cells were examined with varying the gas phase composition, x=$CH_4/\;(SiH_4+CH_4)$, during the deposition of the p-SiC layer. In the range of x=0~0.4, the efficiency of solar cell increased because of the increased band gap of the p-SiC window layer. Further increase in the gas phase composition, however, led to a decrease in the cell efficiency probably due to in the increased composition mismatch at the p-SiC/i-Si layers. As a result, the efficiency of a glass/$SnO_2$/p-SiC/i-SiC/i-Si/n-Si/Ag thin film solar cell with $1cm^2$ area was 8.6% ($V_{oc}$=0.85V, $J_{sc}$=16.42mA/$cm^2$, FF=0.615) under 100mW/$cm^2$ light intensity.