Structural and optical properties of Zn1-x-yAlxSiyO wurtzite heterostructure thin film for photovoltaic applications

The study aims to investigate the optical and structural properties of ZnO wurtzite heterostructure thin films in order to manufacture them as a new generation of solar cell transparent electrodes. With the Sol gel-spin coating process, the pure and co-doped Zinc oxide with different amounts of aluminum and silicon were prepared. The composition was realized in order to obtain thin films with Al + Si contents in the range of 0 at% to 6 at%. XRD patterns exhibit the ZnO wurtzite structure. XPS analysis sustain the presence of Al(3+)and Si3+ in Zn lattice sites. The optical investigations showed that the band gap varies between 3.23 eV and 3.28 eV, showing an increase with increasing the silicon amount. The studied thin films present a significant transmittance parameter in particular the with films having 2 at% of Si and 2% of Al with higher average value which reached 95%.