ELABORATION OF SILICON CLUSTERS BY CVD SILANE OR LASER-ABLATION

Silicon clusters have been promoted by thermal decomposition of Silane (SiH4) on silicon (111)-(7x7). The adsorption of silane molecule at r oom temperature has been studied and a mechanism for adsorption is fou nd to be 2.5 10(-5). The effect of substrate proposed. The sticking co efficient at room temperature was temperature and gas pressure on the formation of clusters has been investigated to determine the process p arameters windows leading to silicon islands formation or epitaxial gr owth by step flow. Furthermore, silicon clusters have been elaborated by laser ablation. The deposit morphology has been observed by AFM stu dies. The structures obtained were found to be luminescent in the visi ble range under UV or visible illumination.