Correlated force and contact-resonance versus displacement responses have been resolved using load-dependent contact-resonance atomic force microscopy (AFM) to determine the elastic modulus of low-k dielectric thin films. The measurements consisted of recording simultaneously both the deflection and resonance frequency shift of an AFM cantilever-probe as the probe was gradually brought in and out of contact. As the applied forces were restricted to the range of adhesive forces, low-k dielectric films of elastic modulus varying from GPa to hundreds of GPa were measurable in this investigation. Over this elastic modulus range, the reliability of load-dependent contactresonance AFM measurements was confirmed by comparing these results with that from picosecond laser acoustics measurements.
Citation: Journal of Materials Research
Pub Type: Journals
nanomechanical properties, atomic force microscopy, low-k dielectric films