Correlation of structure parameters of absorber layer with efficiency of Cu(In, Ga)Se2 solar cell
- 258 Downloads
Polycrystalline Cu(In, Ga)Se2 with Ga-content x=Ga/(In+Ga) ranging from 0.0 (CuInSe2) to 1.0 (CuGaSe2) in heterojunction thin film solar cells were grown by multi-source evaporation. Solar cells with a highest efficiency of η=15.3% need a composition of x≈0.2. At this composition, the c/a ratio of the lattice constants for the tetragonal lattice equals c/a=2, indicating ideal tetragonality. These results suggest that low electronic defect densities occur at x≈0.2, due to the smallest possible crystallographic distortion of the tetragonal lattice at this composition. Cells with high efficiencies require grain sizes above 145 nm and a high preferred orientation (P204/P220 pole density ratio) for the grains.
PACS84.60.Jt 41.50.+h 68.37.Yz 73.40.–c 73.50.Rb
Unable to display preview. Download preview PDF.
- 6.R.A. Young, The Rietveld Method, ed. by R.A. Young (Oxford University Press, London, 1993) Google Scholar