Characterization of cuo/zno:ai p-n junction for solar cell application
Loading...
Date
2014-07-31
Authors
King' ang'i, James Mwiti
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Solar cells with high efficiency and low price have long been desired. However the
commercially available solar cells are still of low efficiencies and expensive. Various elements
and compounds are used to fabricate thin film semi-conductors for solar cell application.
However insufficient literature and data is available on the use of CuO and ZnO:Al for solar cell
application especially by use of spray pyrolysis technique. In this research CuO and ZnO:Al thin
films will be prepared by spray pyrolysis. In order to obtain different samples of CuO, deposition
temperature will be kept constant first while solution molarity will be varied from O.3M to
0.45M. Each of the samples will be characterized separately in order to obtain the solution
molarity which gives the best optical and electrical characteristics. Secondly, the optimised
solution molarity will be kept constant and the deposition temperature will be varied from 2500
to 4000 in order to obtain more samples of CuO prepared at different temperatures. Each of the
samples will also be characterized separately in order to obtain the sample which gives the best
optical and electrical characteristics. To obtain the optimised conditions of ZnO:AI, initially the
deposition temperature will be kept constant while doping percentage will be varied from 1% to
10% to obtain different samples of ZnO:AI thin films. Each of the samples will be characterized
separately. The optimised doping percentage will be kept constant while deposition temperature
will be varied from 2500 to 4000 in order to obtain more samples of ZnO:AI prepared at different
temperatures. Each of these samples will be characterized separately in order to obtain the
sample which gives the best optical and electrical characteristics. Optical properties of each of
the above mentioned samples which include transmittance and reflectance will be measured
using optical spectrum analyser and others which include refractive indices, absorption
coefficients, dielectric constants and energy band gaps will be calculated using scouts software.
Electrical characteristic which is the sheet resistivity will be obtained using four point probe
method. The optimised conditions will be used in the fabrication of solar cell. In the fabrication
of solar cell CuO will be used as absorber layer while ZnO:AI will be the window layer. After
the solar cell has been fabricated, the CuO/ZnO:AI p-n junction will be characterised to obtain its
current voltage characteristics using solar cell simulator. A graph of current against voltage will
be plotted and from the graph solar cell parameters which includes open circuit voltage (Voe) and
short circuit current (Ise) will be determined. Others which include conversion efficiency (11) and
Fill factor (FF) shall be determined from measurements of current and voltage generated across
the solar cell. The fabrication of CuO/ZnO:AI thin film solar cell is expected to offer reliable
solution to design of solar cells with high efficiency from cheap and available resources