Characterization of CuIn1-xGaxS2 thin films grown under thermal gradient by vacuum thermal evaporation method
F. Smaïli*, M. Kanzari
Laboratoire de Photovoltaïque et Matériaux Semi-conducteurs -ENIT BP 37, Le belvédère 1002-Tunis, Tunisie
* Corresponding author. E-mail: email@example.com
Received: 31 January 2009; revised version accepted: 15 June 2010
CuIn1-xGaxS2 thin films with varied Ga content (0<X<1) were prepared by vacuum thermal evaporation in presence of thermal gradient by using simultaneously the CuInS2 and CuGaS2 powders. The CuIn1-xGaxS2 thin films were deposited onto conventional soda lime glass substrates heated at 200 °C during the deposition process. A series of CuIn1-xGaxS2 thin films were obtained by increasing the mCGS/(mCGS+mCIS) mass ratio in the evaporating materials. Structural, morphological and optical properties of the films were studied relating of the Ga content. The (112) peak corresponding to the chalcopyrite structure has been observed to be the dominating peak in all the films. However the (112) peak intensity decreases by increasing the Ga content. From EDX analysis, the Cu:(In+Ga):S atomic ratio in all thin films was approximately 1:1:2. The Ga/(In+Ga) atomic ratio in the thin films changed linearly from 0 to 1.0 by increasing the mCGS/(mCGS+mCIS) mass ratio in the evaporating materials. Low transmission values were found indicating the presence of an opaque aspect due to the presence of a metallic phase in front of the glass substrates.
Keywords: Thin Films; CuIn1-xGaxS2; Structural property; Morphological property.