Ultra-pure organotellurium precursors for the low temperature MOVPE growth of II/VI compound semiconductors
The preparation of a wide range of dialkyltellurium compounds of potential use as the precursors for the epitaxial growth of materials in the CdHgTe system is described. In general these are synthesised by a previously reported route. Methods for the purification of dialkyltelluriums by the formation and dissociation of adducts with Lewis acids are discussed together with the criteria necessary for their successful purification by this method. Finally, an assessment of purity of the alkyls is derived from the spectroscopic analysis of the metal alkyls and by SIMS analysis of layers of cadmium mercury telluride grown from the alkyls.