Interaction between sputtered beta-Ta films and diamond-like carbon with Ru intermediate layer.

Area of Science:

• Materials Science
• Thin Film Technology
• Surface Engineering

Background:

• Diamond-like carbon (DLC) and tantalum (Ta) films are crucial in magnetic recording media.
• Understanding their interfacial interactions under thermal stress is vital for device longevity.

Purpose of the Study:

• To investigate the effect of a ruthenium (Ru) interlayer on the interaction between beta-tantalum and DLC films.
• To evaluate the thermal stability and phase transformations of these films with and without a Ru barrier layer.

Main Methods:

• X-ray Diffraction (XRD) for phase identification and structural analysis.
• X-ray reflectivity (XRR) to assess surface and interfacial characteristics.
• Raman spectroscopy to analyze carbon film structure and graphitization.

Main Results:

• The Ru interlayer significantly delayed the beta-to-alpha phase transformation of tantalum by 100°C and inhibited tantalum carbide formation.
• Minimum intermixing was observed between tantalum and DLC in the presence of Ru, unlike the severe reactions in C/Ta films.
• Carbon films maintained an amorphous structure initially, with graphitization observed upon annealing, but Ru-containing films showed greater thermodynamic stability.

Conclusions:

• Ruthenium interlayers effectively suppress interfacial reactions and phase transformations in Ta/DLC films.
• The enhanced thermal stability and reduced intermixing make Ru-interlayered films highly desirable for advanced magnetic recording applications.