Study of reactive ion etched nanometre size trenches using a combined scanning electron microscope and scanning tunnelling microscope

An instrument incorporating an electrostatic scanning electron microscope (SEM) and a scanning tunnelling microscope (STM) in an ultra high vacuum (UHV) environment has been developed for studying nanostructures. Using this instrument, a detailed study has been made of nanometre size trenches which have been fabricated in silicon nitride using electron beam lithography and a reactive ion etch (RIE) process. This has provided information on the trench dimensions as well as the different etch rates and etch profiles that arise in the fabrication of nanometre size structures.