The current photovoltaic industry is dominated by crystalline or poly-crystalline Si in
a planar pn-junction configuration. The use of silicon nanowire arrays (SiNWA) within
this industry has shown great promise due to its application as an anti-reflective layer,
as well as benefits in charge carrier extraction. In this work, we use a metal assisted
chemical etch process to fabricate SiNWAs onto a dense periodic array of pyramids that
are formed using an alkaline etch masked with an oxide layer. The hybrid micro-nano
structure acts as an anti-reflective coating with experimental reflectivity below 1% over
the visible and near-infrared spectral regions. This represents an improvement of up to
11 and 14 times compared to the pyramid array and SiNWAs on bulk, respectively. In
addition to the experimental work, we optically simulate the hybrid structure using the
commercial Lumerical FDTD package. The results of the optical simulations support our
experimental work, illustrating a reduced reflectivity in the hybrid structure. The nanowire
array increases the absorbed carrier density within the pyramid by providing a guided
transition of the refractive index along the light path from air into the silicon. Furthermore,
electrical simulations which take into account surface and Auger recombination show an
effi ciency increase for the hybrid structure of 56% over bulk, 11% over pyramid array and
8.5% over SiNWAs. Opto-electronic modelling was performed by establishing a tool
flow to integrate the eff ective optical simulator Lumerical FDTD with the excellent fabrication and
electrical simulation capability of Sentaurus TCAD. Interfacing between the two packages
is achieved through tool command language and Matlab, off ering fast and accurate electro-optical
characteristics of nano-structured PV devices.