ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Ultralarge-scale integration circuits now require innovative microfabrication processes in order to achieve gigabit-scale integration. One approach is to use soft x rays, because they can give excellent spatial resolution by their short wavelength and high-reaction selectivity by core-electron excitation. Synchrotron-radiation (SR) -excited etching of SiO2 and Si is studied from the viewpoints of pattern replicability and analysis of etching selectivity between two layers. Deep-submicron patterns of SiO2 are formed by cooling the specimen with liquid N2 and adsorbing SF6 reaction gas during SR irradiation. Photon-stimulated desorption ions from SF6-adsorbed SiO2 and Si surfaces are first investigated. As a result, ion species such as SiF+n and SO+n, which are etching products from the surface, are obtained only from SiO2, and this selective etching of SiO2 is also investigated by x-ray photoelectron spectroscopy. In this selective etching mechanism, constraint of Si-etching by passivation of photofragment S+ ions is most likely. The higher selectivity of this reaction can be used not only for bulk SiO2 etching, but also for Si-surface cleaning by eliminating native oxide.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.355921
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