Modeling of Advanced Light Trapping Approaches in Thin-Film Silicon Solar Cells

ABSTRACTDue to the increasing complexity of thin-film silicon solar cells, the role of computer modeling for analyzing and designing these devices becomes increasingly important. The ASA program was used to study two of these advanced devices. The simulations of an amorphous silicon solar cell with silver nanoparticles embedded in a zinc oxide back reflector demonstrated the negative effect of the parasitic absorption in the particles. When using optical properties of perfectly spherical particles a modest enhancement in the external quantum efficiency was found. The simulations of a tandem micromorph solar cell, in which a zinc oxide based photonic crystal-like multilayer was incorporated as an intermediate reflector (IR), demonstrated that the IR resulted in an enhanced photocurrent in the top cell and could be used to optimize the current matching of the top and bottom cell.

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Improved light trapping effect for thin-film silicon solar cells fabricated on double-textured white glass substrate

Canadian Journal of Physics ◽

10.1139/cjp-2013-0621 ◽

2014 ◽

Vol 92 (7/8) ◽

pp. 920-923 ◽

Cited By ~ 6

Author(s):

Hidetoshi Wada ◽

Keiichi Nishikubo ◽

Porponth Sichanugrist ◽

Makoto Konagai

Keyword(s):

Thin Film ◽

Solar Cells ◽

Solar Cell ◽

Light Trapping ◽

Short Circuit ◽

Silicon Solar Cells ◽

Organic Chemical ◽

Trapping Effect ◽

Thin Film Silicon ◽

Vapor Deposition Technique

Light trapping effect using rough surface transparent conductive oxide (TCO) is one of the best ways to achieve high efficiency thin-film silicon solar cells. Several types of rough ZnO film fabricated by metal organic chemical vapor deposition technique onto the glass, which are etched by reactive ion etching, have been proposed so far as promising TCO substrates. In this paper, newly developed ZnO substrate with extremely high light scattering property comparing with typical pyramidal texture one was developed. By applying this newly developed ZnO substrate to the solar cell, higher short circuit current of about 2% has been achieved comparing with typical pyramidal texture one without sacrificing other parameters. This result showed that the newly developed substrate is suitable as a front TCO substrate for high performance thin-film silicon solar cell.

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Periodic Structures for Improved Light Management in Thin-film Silicon Solar Cells

MRS Proceedings ◽

10.1557/proc-1101-kk08-01 ◽

2008 ◽

Vol 1101 ◽

Cited By ~ 2

Author(s):

Janez Krc ◽

Andrej Campa ◽

Stefan L. Luxembourg ◽

Miro Zeman ◽

Marko Topic

Keyword(s):

Thin Film ◽

Solar Cells ◽

Solar Cell ◽

Photonic Crystal ◽

Amorphous Silicon ◽

Periodic Structures ◽

Light Trapping ◽

Silicon Solar Cells ◽

Thin Film Silicon ◽

Light Management

AbstractAdvanced light management in thin-film solar cells is important in order to improve the photo-current and, thus, to raise up the conversion efficiencies of the solar cells. In this article two types of periodic structures ¡V one-dimensional diffraction gratings and photonic crystals,are analyzed in the direction of showing their potential for improved light trapping in thin-film silicon solar cells. The anti-reflective effects and enhanced scattering at the gratings with the triangular and rectangular features are studied by means of two-dimensional optical simulations. Simulations of the complete microcrystalline solar cell incorporating the gratings at all interfaces are presented. Critical optical issues to be overcome for achieving the performances of the cells with the optimized randomly textured interfaces are pointed out. Reflectance measurements for the designed 12 layer photonic crystal stack consisting of amorphous silicon nitride and amorphous silicon layers are presented and compared with the simulations. High reflectance (up to 99 %) of the stack is measured for a broad wavelength spectrum. By means of optical simulations the potential for using a simple photonic crystal structure as a back reflector in an amorphous silicon solar cell is demonstrated.

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Low-temperature solution growth of textured zinc oxide films for light trapping enhancement in thin film silicon solar cells

RSC Advances ◽

10.1039/c4ra05107f ◽

2014 ◽

Vol 4 (65) ◽

pp. 34669-34673 ◽

Cited By ~ 7

Author(s):

Chao-Ping Liu ◽

Jianzhuo Xin ◽

Lei Wang ◽

Jian-jun Song ◽

Alex Y. S. Lee ◽

...

Keyword(s):

Thin Film ◽

Zinc Oxide ◽

Solar Cells ◽

Light Trapping ◽

Silicon Solar Cells ◽

Zno Film ◽

Zinc Oxide Films ◽

Trapping Effect ◽

Thin Film Silicon ◽

Temperature Solution

Solution based textured ZnO film significantly improves efficiency of thin film silicon solar cells due to its light trapping effect.

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Nanoimprint Lithography of Light Trapping Structures in Sol-gel Coatings for Thin Film Silicon Solar Cells

MRS Proceedings ◽

10.1557/proc-1101-kk13-05 ◽

2008 ◽

Vol 1101 ◽

Author(s):

Maurits Heijna ◽

Jochen Loffler ◽

Bas Van Aken ◽

Wim Soppe ◽

Herman Borg ◽

...

Keyword(s):

Thin Film ◽

Solar Cells ◽

Solar Cell ◽

Barrier Layer ◽

Nanoimprint Lithography ◽

Light Trapping ◽

Silicon Solar Cells ◽

Metal Foil ◽

Periodic Patterns ◽

Thin Film Silicon

AbstractFor thin-film silicon solar cells, light trapping schemes are of uppermost importance to harvest all available sunlight. Typically, superstrates with randomly textured TCO front layers are used to scatter the light diffusively in pin-cells on glass. Here, we investigate methods to texture opaque substrates with both random and periodic textures, for use in nip-cells on metal foil. We applied an electrically insulating SiOx-polymer coating on a stainless steel substrate, and textured this barrier layer by nanoimprint. On this barrier layer the back contact is deposited for further use in the solar cell stack. Replication of masters with various random and periodic sub-micron patterns was tested, and, using scanning electron microscopy, replicas were found to compare well with the originals. The embossing of the barrier layer does not diminish its electrically isolating properties, and thus adds extra functionality to this layer. Masters with U-grooves of various sub-micrometer widths have been used to investigate the optimal dimensions of regular patterns for light trapping in the silicon layers. Angular reflection distributions were measured to evaluate the light scattering properties of both periodic and random patterns. These periodic patterns, comprising diffraction gratings, show promising results in scattering the light to specific angles, enhancing the total internal reflection in the solar cell.

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