Analysis and Optimisation of Two-Dimensional Silicon Complex Grating With Different Ridge Heights or Groove Depths for Solar Cells

In this study, two kinds of two-dimensional (2D) complex gratings are proposed for a potential application as absorbing surfaces for solar cells in the visible and near-infrared wavelength regions, which are based on the superposition of multiple 2D simple gratings with different ridge heights for convex gratings or different groove depths for concave gratings, respectively. Silicon is selected as the complex grating material because it is common in micro/nanofabrication. Compared with one-dimensional (1D) gratings, the new structures present excellent radiative properties to rays from all directions. Besides, the new gratings can achieve satisfactory performance under both TM and TE waves, which cannot be easily obtained by 1D gratings. Furthermore, these two kinds of 2D complex gratings can both achieve higher absorptance in the whole of the interested spectral range by making full use of the microcavity resonance than 2D simple gratings with the same ridge height or groove depth. Taguchi method is employed as an efficient way of searching for the optimal profiles for the 2D complex gratings. The average spectral absorptance of the optimized structure for the 2D complex convex grating with two different ridge heights is above 0.93 within wavelength region from 0.3 to 1.1 μm for both TM and TE waves under normal incidence, which suggests that the proposed structures can be well suitable for solar absorber applications. The Finite-different time-domain (FDTD) method is used for all numerical calculations to obtain spectral absorptance of different structures.© 2013 ASME

[1]  Gang Chen,et al.  Analysis of optical absorption in silicon nanowire arrays for photovoltaic applications. , 2007, Nano letters.

[2]  Huai-Chun Zhou,et al.  Silicon complex grating with different groove depths as an absorber for solar cells , 2014 .

[3]  Olle Inganäs,et al.  Trapping light with micro lenses in thin film organic photovoltaic cells. , 2008, Optics express.

[4]  J. Yu,et al.  Biomimetic parabola-shaped AZO subwavelength grating structures for efficient antireflection of Si-based solar cells , 2011 .

[5]  M. Green The path to 25% silicon solar cell efficiency: History of silicon cell evolution , 2009 .

[6]  Carl Hägglund,et al.  Electromagnetic coupling of light into a silicon solar cell by nanodisk plasmons , 2008 .

[7]  Han Wang,et al.  Effective medium analysis on the optical properties of silicon nanowire arrays , 2012, Other Conferences.

[8]  C. K. Lee,et al.  Design and fabrication of a nanostructured surface combining antireflective and enhanced-hydrophobic effects , 2007 .

[9]  A. Majumdar,et al.  Enhanced thermoelectric performance of rough silicon nanowires , 2008, Nature.

[10]  Yu-Bin Chen,et al.  The profile optimization of periodic nano-structures for wavelength-selective thermophotovoltaic emitters , 2010 .

[11]  Volker Wittwer,et al.  Radiation filters and emitters for the NIR based on periodically structured metal surfaces , 2000 .

[12]  G. Barbastathis,et al.  Nanostructured gradient-index antireflection diffractive optics. , 2011, Optics letters.

[13]  J. G. Fleming,et al.  Three-dimensional photonic-crystal emitter for thermal photovoltaic power generation , 2003 .

[14]  Y. Chen,et al.  Heavily doped silicon complex gratings as wavelength-selective absorbing surfaces , 2008 .

[15]  Carsten Rockstuhl,et al.  Photon management by metallic nanodiscs in thin film solar cells , 2009 .

[16]  James G. Mutitu,et al.  Thin film solar cell design based on photonic crystal and diffractive grating structures. , 2008, Optics express.

[17]  Zongfu Yu,et al.  Optical absorption enhancement in amorphous silicon nanowire and nanocone arrays. , 2009, Nano letters.