J. Phys. III France
Volume 7, Numéro 11, November 1997
Page(s) 2165 - 2169
DOI: 10.1051/jp3:1997249
J. Phys. III France 7 (1997) 2165-2169

CuAlSe $\mathsf{_2}$ Thin Films Obtained by Chalcogenization

S. Marsillac1, K. Benchouk2, C. El Moctar1, J.C. Bernède1, J. Pouzet1, A. Khellil2 and M. Jamali1

1  Équipe Couches Minces et Matériaux Nouveaux, GPSE, FSTN, BP 92208, 2 rue de la Houssinière, 44322 Nantes Cedex 03, France
2  LPMCE, Oran Es Sénia, Algérie

(Received 4 February 1997, revised 23 June 1997, accepted 11 August 1997)

CuAlSe 2 thin films have been synthesized by chalcogenization of thin Cu and Al layers sequentially deposited by evaporation under vacuum. It is shown that CuAlSe 2 films are obtained with some Cu $_{2-\delta}$Se 2 and Se phases present at the surface. These surface phases are suppressed by annealing under vacuum and by chemical etching in a KCN solution. At the end of the process, the XRD spectrum demonstrates that textured CuAlSe 2 films have been obtained with preferential orientation of the crystallites along the (112) direction. The gap of the films is 2.7 eV as expected. The films are nearly stoichiometric, but their surface is quite rough. The XPS spectra show that some Na diffuses from the substrate toward the surface during the annealing process. However, this Na is etched by KCN.

© Les Editions de Physique 1997