Research on ZnO Nanorods Grown on Si Substrate Etched by TMAH as Si Solar Cell Antireflection Layer

doi:10.3724/SP.J.1077.2013.12306

Abstract

Abstract:

An antireflection layer grown on the Si surface of a solar cell can reduce reflection and increase absorption of light. As a result, it can increase the conversion efficiency of the Si solar cell. In this work, (100) Si wafers were anisotropically wet etched by tetramethyl ammonium hydroxide (TMAH) solution and the pyramidal structures were obtained. The minimum reflectivity of etched Si was lower than 6%. Then ZnO nanorods were grown on the Si substrate by a hydrothermal method. The minimum reflectivity of this structure was lower than 3%, better than that from the TMAH etched surface or ZnO nanorods covered surface only. This method has great potential because of its simplicity and high efficiency.

Key words: antireflection layer, tetramethyl ammonium hydroxide, wet etching, anisotropic, ZnO nanorods

CLC Number:

TK514

WANG Tao, QU Xin-Ping. Research on ZnO Nanorods Grown on Si Substrate Etched by TMAH as Si Solar Cell Antireflection Layer[J]. Journal of Inorganic Materials, 2013, 28(4): 420-424.

Figures/Tables 5

Fig. 1 Reflectance of the Si surface after etching in the TMAH solution for different etching time

Fig. 2 Surface and cross-sectional morphologies of Si after etching in the TMAH solution for different time

Fig. 3 Reflectivity of Si wafer after growing ZnO nanorods on the surface with different time using 0.04 mol/L Zinc nitrate hexhydrate and hexamethylene tetramine

Fig. 4 The reflectivity of the Si surface after etching in the TMAH for different times and growing the ZnO nanorods

Fig. 5 The surface morphology and cross-sectional SEM images of the Si substrates after different surface treatments

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