Analyzing periodic and random textured silicon thin film solar cells by Rigorous Coupled Wave Analysis

Abstract

A simple and fast method was developed to determine the quantum efficiency and short circuit current of thin-film silicon solar cells prepared on periodically or randomly textured surfaces. The optics was studied for microcrystalline thin-film silicon solar cells with integrated periodic and random surface textures. Rigorous Coupled Wave Analysis (RCWA) was used to investigate the behaviour of the solar cells. The analysis of the periodic and random textured substrates allows for deriving optimal surface textures. Furthermore, light trapping in periodic and randomly textured substrates will be compared.

Substrate‐independent analysis of microcrystalline silicon thin films using UV Raman spectroscopy

“…The curves were calculated from extinction coefficients measured by Schubert and Dewan et al with ellipsometry . As pointed out previously by Dewan et al , the penetration depth of 325 nm light in a‐Si:H is only 8 nm, and is nearly identical – at 8.5 nm – in μc‐Si:H. However, the penetration depth is not identical to the depth from which Raman signal is collected. The measured Raman intensity I R is attenuated with depth d according to Beer's Law where I 0 is Raman intensity at the sample surface, α is absorption coefficient, and the factor of two accounts for the double‐pass of light (incident in, Raman scattered out) through the sample.…”

Comparison of Light Trapping in Silicon Nanowire and Surface Textured Thin-Film Solar Cells

“…Instead, it is necessary to rigorously solve Maxwell's equations. Currently, there are a number of methods being utilized such as the finite-difference time-domain (FDTD) method [21], finite integration method (FIM) [22] or Rigorous Coupled Wave Analysis (RCWA) [23] capable of simulating near-and far-field wave propagation in such devices. For this study, a FDTD simulation tool is used to investigate the wave propagation within solar cell structures [24].…”

Random versus periodic: Determining light trapping of randomly textured thin film solar cells by the superposition of periodic surface textures

“…It is assumed that the surface can be approximated by the superposition of periodically textured inverted pyramids with a hexagonal base. As a more general approach, the surface can be approximated by the superposition of periodically sinusoidal/ cosinusoidal textured surfaces, which represent the Fourier decomposition of the surface [23][24][25][26]. However, since the experimentally realized structures resemble inverted pyramids we decided to approximate the surfaces directly by inverted pyramids and not by sinusoidal/cosinusoidal textured surfaces.…”