Combined SiO2 antireflective coatings with MOCVD-ZnO:B to improve light absorption in thin-film solar cells

Abstract Boron-doped zinc oxide (ZnO:B or BZO) thin films prepared by metal organic chemical vapor deposition (MOCVD) are widely used as the front contact in thin-film solar cells. However, because reflection at the air/glass interface reduces the absorption of incident light, the short circuit current densities, as well as the efficiencies of the cells are deteriorated. To solve this problem, we proposed the combination of silicon dioxide (SiO2) antireflective (AR) coatings prepared by a sol–gel dip-coating method, with MOCVD-BZO films as the new substrate of the cell. The novel structure of the substrate obtained is: SiO2 AR coatings/glass/BZO. An improvement in the optical properties of the new substrate was achieved by destructive interference of the AR coatings at the coatings/air interface. Appling this novel substrate in amorphous silicon solar cells resulted in significant improvement of both the external quantum efficiency and the performance of the cell.

[1]  C. Lin,et al.  Scalar scattering model of highly textured transparent conducting oxide , 2011 .

[2]  Armin G. Aberle,et al.  Optimised Antireflection Coatings using Silicon Nitride on Textured Silicon Surfaces based on Measurements and Multidimensional Modelling , 2012 .

[3]  Yi Cui,et al.  Absorption enhancement in ultrathin crystalline silicon solar cells with antireflection and light-trapping nanocone gratings. , 2012, Nano letters.

[4]  Michio Kondo,et al.  Improvement in quantum efficiency of thin film Si solar cells due to the suppression of optical reflectance at transparent conducting oxide/Si interface by TiO2∕ZnO antireflection coating , 2006 .

[5]  C. Ballif,et al.  Growth Model of MOCVD Polycrystalline ZnO , 2009 .

[6]  Christophe Ballif,et al.  Opto-electronic properties of rough LP-CVD ZnO:B for use as TCO in thin-film silicon solar cells , 2007 .

[7]  C. Ballif,et al.  Polycrystalline ZnO: B grown by LPCVD as TCO for thin film silicon solar cells , 2010 .

[8]  C. Ballif,et al.  Realization of high efficiency micromorph tandem silicon solar cells on glass and plastic substrates: Issues and potential , 2011 .

[9]  Ertugrul Arpac,et al.  Preparation of antireflective SiO2 nanometric films , 2010 .

[10]  J. Springer,et al.  TCO and light trapping in silicon thin film solar cells , 2004 .

[11]  Sayan Das,et al.  Anti-reflective nanocomposite based coating for crystalline silicon solar cells with noticeable significance , 2013 .

[12]  C. Ballif,et al.  Highly transparent ZnO bilayers by LP-MOCVD as front electrodes for thin-film micromorph silicon solar cells , 2012 .

[13]  Arvind Shah,et al.  Rough ZnO Layers by LP-CVD Process and their Effect in Improving Performances of Amorphous and Microcrystalline Silicon Solar Cells , 2006 .

[14]  Walther Glaubitt,et al.  Antireflective coatings prepared by sol–gel processing: Principles and applications , 2012 .

[15]  Hao-Chung Kuo,et al.  Effects of doping concentration and annealing temperature on properties of highly-oriented Al-doped ZnO films , 2006 .

[16]  Bernd Rech,et al.  Texture etched Al-doped ZnO: a new material for enhanced light trapping in thin film solar cells , 1997, Conference Record of the Twenty Sixth IEEE Photovoltaic Specialists Conference - 1997.

[17]  Dong-Sing Wuu,et al.  Tri-layer antireflection coatings (SiO2/SiO2–TiO2/TiO2) for silicon solar cells using a sol–gel technique , 2006 .

[18]  Eric Mazur,et al.  Near-unity below-band-gap absorption by microstructured silicon , 2001 .

[19]  J. Krč,et al.  Potential of thin-film silicon solar cells by using high haze TCO superstrates , 2010 .

[20]  Hyunsung Park,et al.  Si microwire solar cells: improved efficiency with a conformal SiO2 layer. , 2013, ACS nano.

[21]  A. Chikouche,et al.  Design and simulation of antireflection coating systems for optoelectronic devices : Application to silicon solar cells , 1998 .

[22]  A. Fujishima,et al.  Sol–gel SiO2/TiO2 bilayer films with self-cleaning and antireflection properties , 2008 .

[23]  O. Kluth,et al.  New Generation Transparent LPCVD ZnO Electrodes for Enhanced Photocurrent in Micromorph Solar Cells and Modules , 2011, IEEE Journal of Photovoltaics.