Multi-resonant absorption in ultra-thin silicon solar cells with metallic nanowires

Abstract

We propose a design to confine light absorption in flat and ultra-thin amorphous silicon solar cells with a one-dimensional silver grating embedded in the front window of the cell. We show numerically that multi-resonant light trapping is achieved in both TE and TM polarizations. Each resonance is analyzed in detail and modeled by Fabry-Perot resonances or guided modes via grating coupling. This approach is generalized to a complete amorphous silicon solar cell, with the additional degrees of freedom provided by the buffer layers. These results could guide the design of resonant structures for optimized ultra-thin solar cells.

Multi-resonant silver nano-disk patterned thin film hydrogenated amorphous silicon solar cells for Staebler-Wronski effect compensation

“…We should note that substantially large εʺ can also lead to poor impedance matching, which may be difficult to improve. 36,38 This qualitative analysis is simple, without exploring the detailed parameter space, yet convincingly close to the results obtained by numerical computation using COMSOL in our work, and is similar to the method employed by Massiot, et al 32 To further understand the reason behind the excitation of multiple Fabry-Perot resonances in the NDPSC, the top section of NDPSC as portrayed in Fig. 2(a) (comprising of the ARC, nano-disk, ITO, p-a-Si:H layer and 5 nm of i-a-Si:H layer) was carefully investigated.…”

“…In most plasmonic solar cell literature 12-16, 19, 21, 22-23, 33 it is mainly this near field effect that is thought to be responsible from optical absorption enhancement. In contrast, we employ the plasmonic effect primarily for impedance tuning to excite strong Fabry-Perot resonances 32,37 in the i-layer. It can be noted here that the thin ITO buffer layer aids in tuning the resonance towards a blue shift as also reported by Massiot, et al 32 For shorter wavelengths, the absorption in the i-layer appears to be dominated by the large absorption coefficient of a-Si:H instead of a plasmonic enhancement or Fabry-Perot resonance.…”

Exploring the effective photon management by InP nanoparticles: Broadband light absorption enhancement of InP/In0.53Ga0.47As/InP thin-film photodetectors

“…More details revealing the nature of these optical modes are shown in Figures 7(a) 21 Upon the excitation of these resonances, the density of photons is spatially modulated and maximizes within the regions called "antinode." This provides opportunity to boost the light absorption by increasing the overlapping volume between the active absorber layer and the antinode region.…”

Towards high-efficiency ultra-thin solar cells with nanopatterned metallic front contact

“…Using numerical simulations based on a RCWA method [10][11], we have optimized a full a-Si:H design. Two spacing layers are placed above (10 nm of ITO) and below (15 nm of ZnO:Al) the 90 nm-thick a-Si:H absorber layer in order to avoid metal diffusion [12]. The front contact is made of a 1D silver grating (thickness=20 nm, width=80 nm, period=200 nm) embedded in a 60 nm-thick SiN x layer (inset in Fig.…”