Electric field assisted growth of self-organized CdS films: size dependent structural and optical properties.

This paper presents a systematic study of electric field assisted growth of self-organized cadmium sulphide (CdS) quantum dots (Q-CdS). CdS thin films of self-organized quantum dot like structure with different particle size have been successfully deposited simply by varying the concentration of surfactant in the reaction matrix. The model to describe the self-organization is also discussed. The size of CdS nanoparticles can be altered from 68 nm (corresponding to bulk) to 2 nm. The structural, optical, and morphological properties of Q-CdS films have been investigated. A blue shift has been observed in optical absorption and photoluminescence spectra. The strained growth of Q-CdS films has been observed. The microstructural strain calculated from peak broadening reveals an increase in strain with decreasing particle size. This study may provide a convenient method to deposit size selective and organized nanocrystalline semiconductor thin films.