A multi-component strain-inducing semiconductor region is described. In an embodiment, formation of such a strain-inducing semiconductor region laterally adjacent to a crystalline substrate results in a uniaxial strain imparted to the crystalline substrate, providing a strained crystalline substrate. In one embodiment, the multi-component strain-inducing material region comprises a first portion and a second portion which are separated by an interface. In a specific embodiment, the concentration of charge-carrier dopant impurity atoms of the two portions are different from one another at the interface.