Low-temperature (≤ 350 °C) aluminum-induced layer exchange enables the integration of large-grained polycrystalline silicon–germanium layers into silicon-based optical, electronic, and electromechanical sensors, either in post-processing or at the back-end-of-line of a CMOS flow. We systematically investigate how annealing conditions, metal composition, diffusion control layer, and Al/a-Ge thicknesses influence the crystallization process and the resulting silicon–germanium layer. Our results reveal tunable correlations between process parameters and layer properties, demonstrating that both the crystallinity and the composition of the final layer can be precisely controlled. This work provides practical guidelines for tailoring aluminum-induced layer exchange for silicon–germanium integration across diverse device applications.

We present an analysis of the main mechanisms of dissipation of resonant multilayer double-clamped microbeams in the frequency range 200 to 500 kHz. The devices consist of 2μm thick silicon nitride (E ≈ 160 GPa) beams covered with a polymer IP-Dip (E ≈ 4 GPa) layer fabricated by two-photon polymerization. A laser-Doppler vibrometer was used to measure the resonant vibrations and energy dissipation of the devices in high vacuum (< 0.05 Pa) at room temperature. The experimental findings were compared with theoretical and finite element method (FEM) results. The quality factor, dominated by the intrinsic dissipation in the IP-Dip layer, has proven to have a strong dependence on polymer thickness. On this basis, a viscous model for intrinsic dissipation in a polymer layer was formulated.