Efficient Light Trapping in Inverted Nanopyramid Thin Crystalline Silicon Membranes for Solar Cell Applications

Download
2012-06-01
MAVROKEFALOS, Anastassios
HAN, Sang Eon
Yerci, Selçuk
Branham, Matthew S.
CHEN, Gang
Thin-film crystalline silicon (c-Si) solar cells with light-trapping structures can enhance light absorption within the semiconductor absorber layer and reduce material usage. Here we demonstrate that an inverted nanopyramid light-trapping scheme for c-Si thin films, fabricated at wafer scale via a low-cost wet etching process, significantly enhances absorption within the c-Si layer. A broadband enhancement in absorptance that approaches the Yablo-novitch limit (Yablo-novitch, E. J. Opt. Soc. Am. 1987, 72, 899-907) is achieved with minimal angle dependence. We also show that c-Si films less than 10 pm in thickness can achieve absorptance values comparable to that of planar c-Si wafers thicker than 300 pm, amounting to an over 30-fold reduction in material usage. Furthermore the surface area increases by a factor of only 1.7, which limits surface recombination losses in comparison with other nanostructured light-trapping schemes. These structures will not only significantly curtail both the material and processing cost of solar cells but also allow the high efficiency required to enable viable c-Si thin-film solar cells in the future.
NANO LETTERS

Suggestions

Optical light management by self-arrangement of inverted tetragonal pyramids on the silicon surface through copper-assisted etching technique in a single step
Donercark, Ergi; Çolakoğlu, Tahir; Terlemezoğlu, Makbule; Abak, Musa Kurtulus; Çiftpınar, Emine Hande; Bek, Alpan; Turan, Razit (2022-09-01)
Developing efficient light trapping techniques plays a crucial role in improving silicon (Si) solar cell parameters by decreasing optical losses. Herein, four various surface morphologies by copper-assisted chemical etching (Cu-ACE) technique under various process conditions were developed. The etching solution is composed of copper nitrate trihydrate (Cu[NO3](2)), hydrofluoric acid, and hydrogen peroxide in deionized water. The systematic correlation study on the molarity of the chemical ingredients reveal...
Fabrication of thin crystalline silicon solar cells with advanced light trapping
Hadibrata, Wisnu; Yerci, Selçuk; Turan, Raşit; Department of Micro and Nanotechnology (2017)
Thin crystalline silicon (c-Si) solar cells with thickness in the order of few tens of microns offer many attractive applications, such as, electronic wearables, space probes and satellites thanks to their flexibility and light-weight character. However, reducing the thickness of active layer of silicon solar cells leads to poor light absorption within the silicon layer, especially in the near infrared region of the solar spectrum. The poor absorption becomes problematic for thin c-Si solar cells as it caus...
Enhanced absorption of thin-film photovoltaic cells using an optical cavity
Weinstein, Lee A.; HSU, Wei-Chun; Yerci, Selçuk; Boriskina, Svetlana V.; CHEN, Gang (2015-05-01)
We show via numerical simulations that the absorption and solar energy conversion efficiency of a thin-film photovoltaic (PV) cell can be significantly enhanced by embedding it into an optical cavity. A reflective hemi-ellipsoid with an aperture for sunlight placed over a tilted PV cell reflects unabsorbed photons back to the cell, allowing for multiple opportunities for absorption. Ray tracing simulations predict that with the proposed cavity a textured thin-film silicon cell can exceed the Yablonovitch (L...
Development of hole transport transparent conductive electrodes for n-type crystalline silicon solar cells
Akdemir, Ozan; Bek, Alpan; İmer, Muhsine Bilge; Department of Micro and Nanotechnology (2018)
Conventional transparent conductive electrodes (TCEs) used in crystal silicon (c-Si) solar cells are commonly made of indium tin oxide (ITO) which provides low sheet resistance and high transparency. However, due to indium scarcity, ITO layers increase the fabrication cost; thus, alternative TCEs, such as fluorine-doped tin oxide (FTO), zinc oxide (ZnO), metal nanowires and Oxide/Metal/Oxide (OMO) multilayers, are being investigated. Conventional solar cells also make use of doped layers, to create the junc...
Optimized spacer layer thickness for plasmonic-induced enhancement of photocurrent in a-Si:H
Saleh, Z. M.; NASSER, H; ÖZKOL, E; GÜNÖVEN, M; Abak, Musa Kurtuluş; Canlı, Sedat; Bek, Alpan; Turan, Raşit (2015-10-24)
Plasmonic interfaces consisting of silver nanoparticles of different sizes (50-100 nm) have been processed by the self-assembled dewetting technique and integrated to hydrogenated amorphous silicon (a-Si:H) using SiNx spacer layers to investigate the dependence of optical trapping enhancement on spacer layer thickness through the enhancements in photocurrent. Samples illuminated from the a-Si:H side exhibit a localized surface plasmon resonance (LSPR) that is red-shifted with the increasing particle size an...
Citation Formats
A. MAVROKEFALOS, S. E. HAN, S. Yerci, M. S. Branham, and G. CHEN, “Efficient Light Trapping in Inverted Nanopyramid Thin Crystalline Silicon Membranes for Solar Cell Applications,” NANO LETTERS, pp. 2792–2796, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/29963.