"Utilization of nanoparticles, nanotexturization and quantum dots in silicon and hybrid photovoltaic devices"

Dr. Arturo A. Ayón Ballesteros
Department Of Physics & Astronomy
The University of Texas at San Antonio



The synergistic utilization of nanoparticles in combination with a photon capturing scheme and a suitable field-passivation thin film has enabled the demonstration of silicon n-p junction photovoltaic structures with an efficiency of 15%. Additionally, hybrid (i.e. organic/inorganic) solar cells have been considered as a viable alternative for low-cost photovoltaic devices because the Schottky junction between inorganic and organic materials can be formed employing low temperature processing methods.

We present an efficient hybrid solar cell based on highly ordered silicon nanopillars (SiNPs) and poly (3,4-ethylene-dioxythiophene):polystyrenesulfonate (PEDOT:PSS). The proposed device is formed by spin coating the organic polymer PEDOT:PSS on a SiNP array fabricated using metal assisted electroless chemical etching process.

The characteristics of the hybrid solar cells are investigated as a function of SiNP height. A maximum power conversion efficiency (PCE) of 10.56% has been achieved for an optimized SiNP array hybrid solar cell with nanopillar height of 400 nm, despite the absence of an antireflection coating and a back surface field enhancement. The effect of an ultrathin atomic layer deposition (ALD), grown aluminum oxide (Al2O3), as a passivation layer (recombination barrier) has also been studied for the enhanced electrical performance of the device. With the inclusion of the ultrathin ALD deposited Al2O3 between the SiNP array textured surface and the PEDOT:PSS layer, the PCE of the fabricated device was observed to increase to 10.56%, which is ~10% greater than the corresponding device without the Al2O3 layer.

The device described herein is considered to be promising toward the realization of a low-cost, high-efficiency hybrid solar cell.