Surface Texturing of Crystalline Silicon Solar Cell Using Silicon Nanowires

Abstract

Surface texturing with silicon nanowires on a pyramidal structure was explored by simple metal-assisted chemical etching to improve the electrical performance of a silicon solar cell. The length of nanowires was controlled by changing the etching time in a H 2 O 2 /HF solution after Ag ion adsorption. The weighted reflectance from 300 to 1200 nm was reduced to as low as 4.6% with a 200-nm-long nanowire formed by 30 s etching, while the pyramid surface had a 12.3% reflectance before antireflection (AR) coating deposition. However, the surface textured with 200-nm-long silicon nanowires had a similar reflectance, even after AR coating, and a decreased conversion efficiency in the completed solar cell. Since the silicon wafer with 200-nm-long nanowires had a deep and narrow structure, the AR layer could not be deposited uniformly, which resulted in a low passivation quality and an antireflection effect. This means that the surface structure, even with low reflectance, cannot be appropriate in the cell fabrication process because it is not capable of improving the solar cell performance characteristics. On the other hand, the 30-nm-long nanowire-textured silicon solar cell formed by 2 s etching had a decreased reflectance and improved electrical properties. As a result, the 30-nmlong silicon nanowire-textured solar cell exhibited improved performance characteristics, ÁJ sc ¼ 0:3 mA/cm 2 , ÁV oc ¼ 2 mV, and Á ¼ 0:2%, compared with only a pyramidal textured surface. This suggests that a respectable quality in the passivation and antireflection layers, as well as reflectance reduction, in nanoscale-textured silicon solar cells is required for silicon solar cell performance.

Nanopyramid Formation by Ag Metal-Assisted Chemical Etching for Nanotextured Si Solar Cells

“…Further, several nanostructures have been implemented in order to improve the light absorption of solar cells by wave diffraction effect, which can efficiently transmit light into the Si solar cells and enhance the shunt resistance of pn junction [5][6][7]. Among these nanostructures, nanotextured black Si solar cells have attracted considerable attention due to their low reflectivity over a wide spectral range that improves conversion efficiency to over 18% [8][9][10].…”

Light-trapping performance of silicon thin-film plasmonics solar cells based on indium nanoparticles and various TiO2space layer thicknesses

“…[9][10][11][12][13][14] Metallic NPs involving various materials and having different shapes, sizes, spacings, and environments have been extensively studied. [15][16][17][18][19][20][21][22][23][24][25][26][27][28] However, only scant studies of the use of indium nanoparticles (In NPs) on a TiO 2 space layer to fabricate Si thin-film solar cells have been reported. 29,30) In this study, we evaluated the light trapping performance of Si thin-film solar cells using In NPs on TiO 2 space layers of various thicknesses.…”