Deposition and properties of a-GexCy:H-based superlattice structures

A method for the preparation of a-GexCy:H-based superlattice structures by means of a continuous plasma-enhanced chemical vapor deposition process is presented. A key concept of the method, employing an organogermanium precursor compound and a capacitively coupled RF glow discharge, is to deposit systems of periodically repeating subsequent layers of low and high band gap values by applying a constant composition of feed-in gases and an alternated RF power input. Results of structural investigations using AFM microscopy and X-ray diffractometry, as well as optical (VASE ellipsometry) and electrical (DC conductivity) measurements, are reported, confirming both multilayer topology of the samples and the presence of quantum size effects.