scholarly journals Fabrication of a Silicon Nanowire Solar Cell on a Silicon-on-Insulator Substrate

2019 ◽  
Vol 9 (5) ◽  
pp. 818 ◽  
Author(s):  
Shinya Kato ◽  
Yasuyoshi Kurokawa ◽  
Kazuhiro Gotoh ◽  
Tetsuo Soga

This study proposes metal-assisted chemical etching (MAE) as a facile method to fabricate silicon nanowire (SiNW) array structures, with high optical confinement for thin crystalline silicon solar cells. Conventional SiNW arrays are generally fabricated on Si wafer substrates. However, tests on conventional SiNW-based solar cells cannot determine whether the photo-current is derived from SiNWs or from the Si wafer. Herein, SiNW arrays were fabricated on a silicon-on-insulator substrate with a 10-μm-thick silicon layer for measuring the photocurrent of the SiNW only. The 9 μm-long p-type SiNW arrays were applied to a solar cell structure fabricated using an n-type H-doped amorphous Si layer, thereby confirming the photovoltaic effect. However, the device exhibited a conversion efficiency of 0.0017% because of a low short-circuit current (Jsc) and a low open-circuit voltage (Voc). The low Jsc resulted from a high series resistance and high absorption loss from the amorphous Si layer, whereas the low Voc resulted from the high surface recombination velocity of the SiNW array structure. Therefore, reducing the surface recombination of SiNW-based solar cells can improve their conversion efficiency.

2012 ◽  
Vol 1302 ◽  
Author(s):  
Tai-Yuan Huang ◽  
Ta-Jen Yen

ABSTRACTWe first fabricated a p-type single-crystalline SiNW array as the core by statistic electroless metal deposition (SEMD) method[1]. This structure exhibits per excellent absorption efficiency without increasing the diffusion path, indicating 1.75 times greater performance than Si-based planar solar cells under the same condition[2]. Next, we employed a method of spin-on dopant (SOD) to fabricate an n-type layer as an external thin shell, which benefits to decouple the absorption of light from charge transport by allowing lateral diffusion of minority carriers to the p-n junction rather than many microns away as in Si bulk solar cells, and is suitable for our SiNW array with a hydrophilic surface. Finally, our SiNW-based solar cell possesses strong broadband absorption and low reflection from visible light to near IR, in which the highly light trapping mechanism stems from the effective medium theory (EMT) to demonstrate only less than 3% of total reflectance in the range of 500-1100 nm. It also shows conversion efficiency improvement of 20% compared with the planar single-crystalline Si solar cell by the same fabrication processes. The proposed novel photovoltaic device by our core-shell SiNW array revolutionizes the current architecture of solar cells, promising niche points of (1) better absorption, (2) self-antireflection, and (3) low-cost process.


2018 ◽  
Vol 2018 ◽  
pp. 1-5 ◽  
Author(s):  
Xing Yang ◽  
Jiangtao Bian ◽  
Zhengxin Liu ◽  
Shuai Li ◽  
Chao Chen ◽  
...  

A conversion efficiency of 20.23% of heterojunction with intrinsic thin layer (HIT) solar cell on 156 mm × 156 mm metallurgical Si wafer has been obtained. Applying AFORS-HET software simulation, HIT solar cell with metallurgical Si was investigated with regard to impurity concentration, compensation level, and their impacts on cell performance. It is known that a small amount of impurity in metallurgical Si materials is not harmful to solar cell properties.


2015 ◽  
Vol 815 ◽  
pp. 72-75
Author(s):  
Liu Qiao ◽  
Yan Jun Wang ◽  
Xue Nan Zhang ◽  
Zheng Liu ◽  
Jia Liu ◽  
...  

The center of czochralski (CZ) wafer for solar cell often has black center, due to the existence of high impurities content, many defects such as dislocations. This has serious effect on solar cells’ conversion efficiency. To solve this problem, we developed a new kind of material-czochralski and floating zone (CFZ) silicon. But there is still black center in the CFZ-Si wafer with conventional process. In order to solve this problem successfully a new technology-alternant forward and reverse rotation was introduced. By testing the crystal defects, metal and oxygen impurities content, it has been found that the black center is related to oxygen distribution in the wafer. However since the content was very low and not enough to affect the solar cells’ conversion efficiency, which has been testified in solar cell. Therefore CFZ technology offers a new kind of silicon material, which can avoid the black center problem in CZ silicon wafer.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Lingsheng Zeng ◽  
Xuegong Yu ◽  
Yangang Han ◽  
Deren Yang

Vertical silicon nanowire (Si NW) arrays on a Si (100) substrate have been prepared by using a low-cost and facile Ag-assisted chemical etching technique. The reflectance of Si NW arrays is very low (<1%) in the spectral range from 400 to 1000 nm. By phosphorus diffusion into Si NW arrays to fabricate solar cells, the power conversion efficiency of 8.84% has been achieved. This power conversion efficiency is much higher than that of the planar cell with the similar celling technology. It is found that the efficiency of Si NW solar cells is intimately associated with their excellent antireflection property. The surface recombination of Si NWs is the main obstacle for the improvement of solar cell efficiency. The current results are helpful to the advancement of the application of Si NWs in photovoltaics.


2009 ◽  
Vol 1210 ◽  
Author(s):  
Hirotada Inoue ◽  
Yasufumi Tsunomura ◽  
Daisuke Fujishima ◽  
Ayumu Yano ◽  
Shigeharu Taira ◽  
...  

AbstractIn order to reduce the power-generating cost of silicon solar cells, it is necessary to achieve a high conversion efficiency using a thinner crystalline silicon (c-Si) substrate. The HIT (Heterojunction with Intrinsic Thin-layer) solar cell is an amorphous silicon (a-Si) / c-Si heterojunction solar cell that exhibits the potential to make this possible. Our recent R&D activities have achieved the world’s highest conversion efficiency of 23.0% with a practical sized (100.4 cm2) HIT solar cell, by improving the quality of the surface passivation, reducing the optical absorption loss and reducing the resistance loss. We have also developed a HIT solar cell with a thickness of only 98 mm, which has a very high conversion efficiency of 22.8%. This value is comparable to that of the conventional HIT solar cell, which has a thickness of more than 200 mm. Moreover, we have fabricated HIT solar cells using thinner c-Si substrates (96 to 58 μm), and found that the Voc increased with decreases in the substrate thickness, and reached an extremely high value of 0.745 V with a thickness of only 58 μm. This indicates that the surface recombination velocity of the HIT structure is extremely low due to the excellent passivation of the c-Si surface.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
S. Wageh ◽  
Mahfoudh Raïssi ◽  
Thomas Berthelot ◽  
Matthieu Laurent ◽  
Didier Rousseau ◽  
...  

AbstractPoly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) mixed with single-wall nanotubes (SWNTs) (10:1) and doped with (0.1 M) perchloric acid (HClO4) in a solution-processed film, working as an excellent thin transparent conducting film (TCF) in organic solar cells, was investigated. This new electrode structure can be an outstanding substitute for conventional indium tin oxide (ITO) for applications in flexible solar cells due to the potential of attaining high transparency with enhanced conductivity, good flexibility, and good durability via a low-cost process over a large area. In addition, solution-processed vanadium oxide (VOx) doped with a small amount of PEDOT-PSS(PH1000) can be applied as a hole transport layer (HTL) for achieving high efficiency and stability. From these viewpoints, we investigate the benefit of using printed SWNTs-PEDOT-PSS doped with HClO4 as a transparent conducting electrode in a flexible organic solar cell. Additionally, we applied a VOx-PEDOT-PSS thin film as a hole transporting layer and a blend of PTB7 (polythieno[3,4-b] thiophene/benzodithiophene): PC71BM (phenyl-C71-butyric acid methyl ester) as an active layer in devices. Zinc oxide (ZnO) nanoparticles were applied as an electron transport layer and Ag was used as the top electrode. The proposed solar cell structure showed an enhancement in short-circuit current, power conversion efficiency, and stability relative to a conventional cell based on ITO. This result suggests a great carrier injection throughout the interfacial layer, high conductivity and transparency, as well as firm adherence for the new electrode.


Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 592
Author(s):  
Myeong Sang Jeong ◽  
Yonghwan Lee ◽  
Ka-Hyun Kim ◽  
Sungjin Choi ◽  
Min Gu Kang ◽  
...  

In the fabrication of crystalline silicon solar cells, the contact properties between the front metal electrode and silicon are one of the most important parameters for achieving high-efficiency, as it is an integral element in the formation of solar cell electrodes. This entails an increase in the surface recombination velocity and a drop in the open-circuit voltage of the solar cell; hence, controlling the recombination velocity at the metal-silicon interface becomes a critical factor in the process. In this study, the distribution of Ag crystallites formed on the silicon-metal interface, the surface recombination velocity in the silicon-metal interface and the resulting changes in the performance of the Passivated Emitter and Rear Contact (PERC) solar cells were analyzed by controlling the firing temperature. The Ag crystallite distribution gradually increased corresponding to a firing temperature increase from 850 ∘C to 950 ∘C. The surface recombination velocity at the silicon-metal interface increased from 353 to 599 cm/s and the open-circuit voltage of the PERC solar cell decreased from 659.7 to 647 mV. Technology Computer-Aided Design (TCAD) simulation was used for detailed analysis on the effect of the surface recombination velocity at the silicon-metal interface on the PERC solar cell performance. Simulations showed that the increase in the distribution of Ag crystallites and surface recombination velocity at the silicon-metal interface played an important role in the decrease of open-circuit voltage of the PERC solar cell at temperatures of 850–900 ∘C, whereas the damage caused by the emitter over fire was determined as the main cause of the voltage drop at 950 ∘C. These results are expected to serve as a steppingstone for further research on improvement in the silicon-metal interface properties of silicon-based solar cells and investigation on high-efficiency solar cells.


2021 ◽  
Vol 42 (4) ◽  
pp. 469-472
Author(s):  
Yingtao Yu ◽  
Si Chen ◽  
Qitao Hu ◽  
Paul Solomon ◽  
Zhen Zhang

2015 ◽  
Vol 19 (01-03) ◽  
pp. 175-191 ◽  
Author(s):  
Ganesh D. Sharma ◽  
Galateia E. Zervaki ◽  
Kalliopi Ladomenou ◽  
Emmanuel N. Koukaras ◽  
Panagiotis P. Angaridis ◽  
...  

Two porphyrin dyads with the donor-π-acceptor molecular architecture, namely ( ZnP )-[triazine-gly]-( H 2 PCOOH ) and ( ZnP )-[triazine-Npip]-( H 2 PCOOH ), which consist of a zinc-metalated porphyrin unit and a free-base porphyrin unit covalently linked at their peripheries to a central triazine group, substituted either by a glycine in the former or a N-piperidine group in the latter, have been synthesized via consecutive amination substitution reactions of cyanuric chloride. The UV-vis absorption spectra and cyclic-voltammetry measurements of the two dyads, as well as theoretical calculations based on Density Functional Theory, suggest that they have suitable frontier orbital energy levels for use as sensitizers in dye-sensitized solar cells. Dye-sensitized solar cells based on ( ZnP )-[triazine-gly]-( H 2 PCOOH ) and ( ZnP )-[triazine-Npip]-( H 2 PCOOH ) have been fabricated, and they were found to exhibit power conversion efficiency values of 5.44 and 4.15%, respectively. Photovoltaic measurements (J–V curves) and incident photon to current conversion efficiency spectra of the two solar cells suggest that the higher power conversion efficiency value of the former solar cell is a result of its enhanced short circuit current, open circuit voltage, and fill factor values, as well as higher dye loading. This is ascribed to the existence of two carboxylic acid anchoring groups in ( ZnP )-[triazine-gly]-( H 2 PCOOH ), compared to one carboxylic acid group in ( ZnP )-[triazine-Npip]-( H 2 PCOOH ), which leads to a more effective binding onto the TiO 2 photoanode. Electrochemical impedance spectra show evidence that the ( ZnP )-[triazine-gly]-( H 2 PCOOH ) based solar cell exhibits a longer electron lifetime and more effective suppression of charge recombination reactions between the injected electrons and electrolyte.


2022 ◽  
Author(s):  
Ehsan Elahi ◽  
Ghulam Dastgeer ◽  
Abdul Subhan Siddiqui ◽  
Supriya A. Patil ◽  
Muhammad Waqas Iqbal ◽  
...  

With perovskite materials, rapid progress in power conversion efficiency (PCE) to reach 25% has gained a significant amount of attention from the solar cell industry.


Sign in / Sign up

Export Citation Format

Share Document