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Updated: Jan 24, 2026
Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures
Published on: December 5, 2015
Damage-induced voltage alteration (DIVA) contrast in SEM images of ion-irradiated semiconductors
Iwona Jóźwik1, Adam Barcz2, Elżbieta Dąbrowska3
1Łukasiewicz Research Network - Institute of Electronic Materials Technology, 133 Wólczyńska Str., 01-919 Warsaw, Poland; National Centre for Nuclear Research/NOMATEN Centre of Excellence MAB+ Division, 7th A. Soltana Str., Świerk-Otwock, Poland.
Abstract:
The ion-irradiation damage effects in semiconductors were directly visualized by means of scanning electron microscopy at low beam acceleration voltages (low-kV SEM). The Al0.55Ga0.45As (p-type and n-type) epitaxial layers grown over GaAs substrates were irradiated with energetic He+ ions with fluencies ranging from 8e12 to 8e13 cm-2 and studied in cross-sectional view after cleavage. Secondary electron images collected at low energy (0.5 - 1 keV) of primary electrons show strong contrast related to the local differences in the material resistivity resulting from the ion-induced damage. The main aim of the paper is to present, for the first time, the interpretation of the mechanism of SEM image contrast formation, which has been referred to as Damage-Induced Voltage Alteration (DIVA) contrast and is based on the charging effect in SEM. The unrivalled advantage of this imaging technique is the possibility of immediate two-dimensional visualization of damage effects without complex sample preparation.
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