(0 0 1) textured L1(0) FePt/B4C multilayer thin films have been prepared on amorphous substrates by magnetron sputtering. High resolution transmission electron microscopy investigation indicates that the Fe and Pt atoms stacked alternately along the c-axis of L1(0) FePt, confirming the formation of the superlattice structure of L1(0)-ordered FePt. The internal stress calculation and geometrical phase analysis confirm the existence of the in-plane tensile strain in the L1(0) FePt thin films. The diffusion of the B and C atoms into the FePt layers results in expansion of the FePt unit cells in the interfaces, which induces an in-plane tensile strain in the adjacent deep parts of FePt layer. Such an in-plane tensile strain creates a favorable condition for the FePt films to stabilize the (0 0 1) texture because it relaxes the ordering strain energy of FePt during phase transformation. (C) 2015 Elsevier B.V. All rights reserved.