Germanium atomic layer epitaxy controlled by surface chemical reactions

Article abstract of DOI:10.1149/1.2097029

Atomic layer epitaxy (ALE) using surface chemical reactions has attracted major interest as a method for the preparation of ultrathin II-VI and III-V compound semiconductor film. These ALE processes use surface reactions which occur between two kinds of gaseous reactants introduced alternately onto the surface. As a result, each monolayer composed of different elements is produced alternately. In this paper, a novel layer-by-layer Ge epitaxial growth technique using GeEt₂H₂ (Et=C₂H₅) gas surface reaction is proposed and film depositions by this technique are experimentally demonstrated. This technique is based on the repetition of a sequential process consisting of gas introduction on the Ge surface at 220°C, gas evacuation, and Et group desorption at temperatures over 400°C.