The determination of the elastic modulus of microcantilever beams using atomic force microscopy

An investigation into the determination of the micromechanical properties of thin film materials has been performed. Thin metal and ceramic films are used extensively in the computer microprocessor industry and in the field of micro-electromechanical systems (MEMS). The demand for miniaturization and increased performance has resulted in the use of materials without a clear understanding of their mechanical properties on this scale. Micromechanical properties are difficult to obtain due to the lack of adequate testing equipment. The atomic force microscope (AFM), most commonly used as an imaging tool, lends itself to mechanical interaction with the sample surface utilizing a cantilever probe. An array of aluminum microcantilever beams were fabricated using standard IC processing techniques. The microbeams were deflected by the AFM cantilever probe and from this, the micromechanical properties of stiffness and elastic modulus were determined. Initial results indicate that this technique reliably determines the micromechanical properties of thin films.