Promoting inter-diffusion behavior of Co/Si (100) films by high magnetic field annealing

• Interdiffusion in film/semiconductor by high magnetic field annealing was studied.
• XPS results showed diffusion coefficients were promoted by a high magnetic field.
• Coefficient decreased by a high magnetic field at 400 °C might due to phase change.

The effects of high magnetic field annealing on the inter-diffusion behavior of Co/Si (100) films were investigated using diffusion couple technique. Significant Co and Si inter-diffusion was verified by X-ray photoelectron spectroscopy. The inter-diffusion coefficients of thin-film/semiconductor were calculated. Compared to the no-field case, the inter-diffusion coefficients clearly increased when a high magnetic field of 11.5 T was applied at 300 °C, 350 °C, 450 °C and 500 °C. This effect can be attributed to an increase in the chemical potential gradient induced by magnetic free energy in a high magnetic field. For the samples at 400 °C, the inter-diffusion coefficients decreased when a high magnetic field of 11.5 T was applied. The phenomenon may due to the structure transformation caused by a high magnetic field.