Molecular layer etching of GaAs

Abstract
Layer‐by‐layer controlled molecular layer self‐limiting etching at one molecular layer of GaAs was successfully achieved for the first time by alternatively feeding an etchant of Cl and applying a low energy Ar ion beam to the GaAs substrate. The etching rate saturates exactly at one molecular layer per cycle and is independent of etchant feeding rate and the energetic ion beam flux.