Preparation of thin layers of ferromagnetic manganese silicides and germanides

Laser ablation of an Mn target in several Pa of a reactive background gas (SiH₄ or GeH₄) leads to the preparation of manganese silicides and germanides. Deposited layers are mainly amorphous; however, annealing at 600 °C (silicides) or 350 °C (germanides) triggers the crystallization of nanoparticles. Different crystalline phases of silicides (Mn₄Si₇, Mn₅Si₃, Mn₅Si₂) or germanides (GeMn a Mn₅Ge₃) can be produced, depending on the conditions (especially the pressure of a gas precursor and annealing temperature). Improvement of ferromagnetic properties is observed with increased crystallization of the layers.