Nanostructure Fabrication: Dry Etching Damage

Abstract

AbstractAlthough the directed energy and chemical reactivity of dry etching permits the fabrication of nanostructures with precise geometries, it also causes unwanted electrical and optical changes to the surface, changes generally referred to as “damage”.This paper discusses the extent and the impact of dry-etching damage on rI-V and I[-VI compound semiconductors as assessed by a very wide range of techniques: the performance of devices such as MESFETs, and measurements of other properties - surface uniformly and precisely, Schottky junction characteristics, cut-off of epitaxial wire conductance, integrated photoluminescence, X-ray reflectivity, DLTS, TEM imaging and Raman scattering.We distinguish an important difference between the nature of damage on sidewalls and on surfaces normal to the directed ions, and report on progress towards establishing a model of the nature of dry etching damage. This model is applied to indicate what kinds of processes are likely to give etching with low damage.