Interlayer microstructure of sputtered Mo/Si multilayers

K-edge transmission-mode extended x-ray absorption fine structure, transmission electron microscopy, and x-ray diffraction have been used to investigate the microstructure of Mo/Si multilayers with periods ranging from 20 to 2.0 nm (the layer thickness ratios of Mo to Si were 1:2). The results confirmed that there was a Mo-Si amorphous interlayer between the Mo and Si layers, the Mo-Si coordination was about 80% in the first shell neighbouring the Mo atom in the interlayer, and the total coordination number was 7.4, approximately equal to that of bcc Mo. A thermally activated model is suggested as a basis for explaining the interlayer formation mechanism by considering the different thermal conductivities of the deposited Mo and the amorphous Si surfaces. (author)