Development of Vibrating Reed Machine for Measuring Young's Modulus of Thin Films

This paper describes the vibrating reed machine developed for measuring Young's modulus of thin films. The developed machine measures a resonance frequency with 0.001Hz resolution for determining Young's modulus of thin films in vibrating reed method. Young's modulus of sputtered Cr films, of which thickness was ranged from 0.2μm to 6μm, were measured. The Young's modulus of Cr thin films of 3-6μm in thickness agreed with the bulk Young's modulus of pure Cr, while the Young's modulus of 0.2-0.3μm thin films was about twice larger than that of the bulk material. The Young's modulus of Cr thin films measured in vibrating reed method agreed well with that measured in the 3-points bending method. The increase in Young's modulus with decreasing film thickness was discussed by the microstructure observed by SEM and X-ray diffraction.