Enhanced Light Trapping in Thin Film Solar Cells Using a Plasmonic Fishnet Structure

Abstract

Incorporating plasmonic structures into the back spacer layer of thin film solar cells (TFSCs) is an efficient way to improve their performance. The fishnet structure is used to enhance light trapping. Unlike other previously suggested discrete plasmonic particles, the fishnet is an electrically connected wire mesh that does not result in light field localization, which leads to high absorption losses. The design was verified experimentally. A silver fishnet structure was fabricated using electron beam lithography (EBL) and thermal evaporation. The final fabricated structure optically resembles a TFSC. The results predicted by numerical simulations were reproduced experimentally on a fabricated sample. We show that light absorption in the a-Si absorber layer is enhanced by a factor of 10.6 at the design wavelength of 690 nm due to the presence of the fishnet structure. Furthermore, the total absorption over all wavelengths was increased by a factor of 3.2. The short-circuit current of the TFSC was increased by 30% as a result of including the fishnet.

Effective electrical resistivity in a square array of oriented square inclusions

“…While hexagonal tiling is theoretically more efficient [1], and may exhibit marginally superior physical properties [e.g. 2], quadratic arrays with quadratic sub-features are often easier to manufacture and operate, as evidenced by their prevailing occurrence in micro-optoelectronic devices and electromagnetic metamaterial applications [3][4][5][6][7][8][9][10][11]. The broad range of target materials considered in this paper includes various types of biosensors, plasmonic materials, and optoelectronic devices (figure 1), all of which can be modeled as bi-or multi-composites as follows.…”

“…At this point we note that equation (5) qualifies as a purely algebraic extension of equation (2), since it reduces to the latter for c=1/4. To test the validity of equation (5) for other values of c, we compare it to finite element model simulations, as described next.…”

Effect of sputtering pressure on the structure and properties of SiO 2 films prepared by magnetron sputtering

“…One is to improve the efficiency of the cell itself, the other is to reduce the loss of incident light, that is, to reduce reflection. To reduce reflection, one method is coating the surface of the cell glass cover with a film, the other is processing the surface of the glass cover or the solar cell into a light trapping structure which can increase the surface roughness and scattering, double the optical path and enhance the absorption of light [1]. For the space solar cell, in order to improve its service life and resist the damage of space radiation or high‐energy particles, it is generally necessary to cover the top of cell with a glass cover, so the main way to reduce the reflection is to use antireflection film.…”