الفهرس 
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Abstract
In the areas of science and technology, measurements of small strains (<10-6) are required. At present, strain measurement are usually performed by means of conventional strain gauges which utilize the variation of the resistance of an elastically strained wire to measure the strain in specimen to the surface of which the wire is firmly attached. Hence a higher accuracy may be achieved by exploiting the effects which couple strains and resistivety in a non-linear fashion. One obvious choice is the metallic thin film.
In our work, we have discussed an analytical method (modeling) for the ability of some metallic films to form strain gauges with a relatively high gauge factor and low TCR.
In the case of discontinuous metallic films we have developed a model depending on a tunneling conduction mechanism. In this model, we have considered the metal islands to form arrays of sphere-segments and we have calculated the activation energy, the conductivity, the potential difference between the island gaps, the gauge factor and the TCR. We have applied this model on Au, Ni and Pt films, the gauge factor for of these films were near to each other (maximum value ≈ 85) but, the gauge factor for Au was more stable with temperature than the others.
In the case of continuous metallic films the choice of a suitable material depends on the gauge factor and is given by , we took into consideration the effect of the temperature on the electron mean free path which is given by[49] = A0T –5
We applied this model on Ni, Al and Cu films, the gauge factors for all these films were near to each other, it was also found that Ni films were more stable with temperature than the others.