Raman study of germanium nanowires formed by low energy Ag+ ion implantation

Laser‐induced heating of porous Ge layers implanted with Ag+ and Cu+ ions

“…Figure 4 shows the results of the change in f under the action of the probing He‐Ne (Figure 4a) and solid‐state laser radiation (Figure 4b) in Ag:PGe and Cu:PGe samples. These dependencies are in agreement with the previously obtained results, [ 16 ] which stated that the implanted Ag:PGe were amorphous. The value of f in the Ag:PGe samples was equal to zero even when the maximum value ( P laser = 7–8 mW, λ = 633 nm) of the exciting laser power was reached (Figure 4a).…”

“…PGe layers prepared by implantation of both Ag + and Cu + ions were studied using Raman spectroscopy in a manner described thoroughly in the work. [ 16 ] Cycles of measurements with first increasing and then decreasing excitation P laser were performed to ensure the irreversible changes of the crystalline volume fraction ( f ) in PGe layers upon exposure to a probing laser radiation. Figure 2 demonstrates the effect of local heating and subsequent partial crystallization of sample 1 under the solid‐state laser ( λ = 532 nm) excitation.…”

“…The ion beam energies were E Ag + = 30 keV and E Cu + = 40 keV, respectively. The ion dose D was ranging from 9.8Á10 16 to 1.5Á10 17 ion/cm 2 for Ag:PGe and from 9.3Á10 16 to 1.5Á10 17 ion/cm 2 for Cu:PGe implanted samples (see Table 1). The thickness of the implanted layer was estimated by the same method as in the work.…”

Heat Treatment Effect on Structural and Optical Properties of Germanium Nanowires Obtained by Electrochemical Deposition

“…It was reported that Ge NW layers formed by implanting a Ge substrate with Ag + ions were also investigated by Raman scattering. [ 21 ] It was found that the threshold values in the study of samples obtained by ion implantation with a He–Ne laser exceed the threshold values of the samples studied in this work. When studying samples obtained by ion implantation using a He–Ne laser, the crystallization threshold reached 3000 W cm −2 .…”

“…Comparing the presented results and the results obtained in the study of Ge NW formed by ion implantation, [ 21 ] one should pay attention to the diffuse reflection spectrum of the Ge substrate itself and the implanted layer. [ 23 ] The dependence of diffuse reflection for implanted layers increases with increasing wavelength, whereas for those investigated in this work, on the contrary, decreases.…”