Piezoresistive effect in p-type silicon classical nanowires at high uniaxial strains

The longitudinal piezoresistance of the p-type silicon nanowires oriented along the 〈100〉, 〈110〉 and 〈111〉 crystallographic directions is examined at high uniaxial compressive and tensile elastic stresses ∼1 GPa. The detail research on base of the six-band model of the valence band involves quantum kinetic approach to calculation of the kinetic coefficients (conductivity, mobility) in classical nanowires with diameter that is significant higher the de Broglie wavelength of the band carriers. Two mechanisms of scattering (charged impurities and longitudinal acoustic phonons) are investigated. Qualitative agreement has been reached between calculated and known experimental data. A quantitative agreement with experiment is obtained in assumption about a formation of the stress concentration (stress raisers) in regions of nanowires that are depleted by the band carriers.