Influence of CdS growth process on structural and photovoltaic properties of CdTe/CdS solar cells

The morphology of CdS layers grown by chemical bath deposition (CBD) and high vacuum evaporation (HVE) have been investigated. The grains of CBD-CdS are more compact and smooth than those of HVE-CdS. The annealing and CdCl 2 treatment cause grain growth, which is stronger for the CdCl 2 treated samples. The grain-size of the as-deposited CdTe on CBD-CdS is about 5 times larger than of those grown on HVE-CdS. The structural and electrical properties of CdTe/CdS solar cells are strongly dependent on the CdS. The grain size of CdCl 2 treated CdTe layers are similar, irrespective of the transparent conducting oxide substrate and CdS deposition method. The e$ciency of solar cells on thin CBD-CdS is low (about 5.6%) because of pin-holes and a large intermixing of CdTe-CdS. The cells on HVE-CdS yield a higher current density despite thicker HVE-CdS as compared to CBD-CdS. The e$ciency of solar cells on HVE-CdS is 12.3%. ( 2001 Elsevier Science B.V. All rights reserved.