Influence of annealing temperature and Au concentration on the electrical properties of multilayered a-Ge/Au films

Multilayered a-Ge/Au was investigated to realize low-temperature formation of poly-Ge films on insulator. Increasing Au layer thicknesses, peak intensity of crystalline Ge–Ge TO mode increased and amorphous Ge–Ge TO mode decreased. When Au composition ratio is high, the samples are crystallized under eutectic temperature. Annealing temperature at 673 K, all samples with Au layer are crystallized. Crystalline Ge has no strain evaluated by X-ray diffraction and Raman scattering spectroscopy. However, the Au is compressed or expanded in the films with various annealing temperature. It is thought that this phenomenon changes depending on the size of the space in the film. The behavior of electrical resistivity is changed at eutectic temperature.

► Metal induced crystallization was investigated in multilayered a-Ge/Au structure. ► We are successful to reduce the annealing time with multilayered structure. ► Grain size of Au and Ge is increased with increasing annealing temperature. ► The behavior of electrical resistivity is changed at eutectic temperature.