Formation and Device Application of Ge Nanowire Heterostructures via Rapid Thermal Annealing
Figure 6
Cross-sectional TEM study of a Ni-Ge nanowire device on a SiO2/Si substrate cut with FIB. (a) Low-magnification cross-sectional TEM image of the NiGe region. The 20 nm thick Al2O3 film provides a conformal capping on the device surface and germanide nanoparticles are clearly observed as they segregated underneath the nanowire, the region that is not covered by Al2O3. (b) Lattice-resolved HRTEM image of the interface between the formed NiGe nanowire (NW) and the segregated NiGe nanoparticle (NP), as indicated by the white rectangle in Figure 5(a). The inset shows the corresponding FFT pattern. The labeled lattice spacings for NiGe are: nm and nm. (c) Cross-sectional TEM image with the line-scan profiles of Ge, Ni, Al and O atoms. (d)–(g) The individual line-scan profile of Ge, Ni, Al, and O atoms, respectively, The Ni/Ge ratio is about 1 : 1. Reproduced from [14].
