Comprehensive study of focused ion beam induced lateral damage in silicon by scanning probe microscopy techniques

Abstract

Scanning probe microscopy techniques and, in particular, scanning spreading resistance microscopy (SSRM) were used for a detailed characterization of focused ion beam (FIB) induced damage in the surrounding of purposely irradiated areas on silicon. It is shown that the damaged area detected using these techniques extends up to several micrometers around the irradiated structures. The influence of the key FIB processing parameters on the FIB induced damage was examined. Parameters which were taken into account are the ion dose (from 1012 to 1018 cm−2), the milled structure size (circle diameters from 0.25 to 10 µm), the beam energy (from 10 to 30 keV), and the beam current (from 1.5 to 280 pA). Moreover, the influence of the SSRM settings on the measurement results was investigate d. Settings which were considered are the bias voltage and the force applied to the tip during the SSRM analysis. High resolution transmission electron microscopy and secondary ion mass spectroscopy analyses were performed to validate the SSRM results. Scattering between Ga ions and residual gas particles in the vacuum chamber of the FIB tool is identified as the main reason for the observed damaged area

Nanoscale investigation of deformation characteristics in a polycrystalline silicon carbide

“…In contrast, a study of nanoindentation on SiC coating (59-μm thick) [27] showed an increased hardness and elastic modulus after irradiation, which was attributed to the irradiation-induced point defects that impeded the movement of dislocations. In this study, the observed behaviour at lower loads (1 to 3 mN) was most likely due to Ga ion implantation on the surface [28,29], which hardened the surface layer of the material by obstructing dislocation movement.…”

3D Free‐Form Patterning of Silicon by Ion Implantation, Silicon Deposition, and Selective Silicon Etching

“…This is confirmed by the fast Fourier transform (FFT) analysis shown in Figure 5c. Amorphization of Si is a known result of FIB Ga + ion implantation,37 and the subsequent annealing steps have caused re‐crystallization of the amorphized Si to a polycrystalline state.…”

Process considerations for layer-by-layer 3D patterning of silicon, using ion implantation, silicon deposition, and selective silicon etching

“…However, implantation of Ga þ ions into Si breaks down the crystalline structure and leaves the implanted surface layer amorphous. 30 Subsequent Si growth will thus be polycrystalline on implanted layers, while epitaxy is still possible outside implanted areas. As a result, the thickness of the layer grown on the implanted areas can be up to double the thickness of the layer grown on nonimplanted areas.…”