GROWTH OF EPITAXIAL BETA-FESI2 ON (100)SILICON USING FE-TI-SI DIFFUSION COUPLES

Epitaxial semiconducting iron-disilicide grains have been formed using an Fe-Ti bilayer on (100) silicon. The reaction kinetics of the Fe-Ti-Si diffusion couple have been studied in detail as a function of annealing conditions, and the intermediate titanium thickness. Both rapid thermal annealing and long-time furnace annealing have been used in this investigation. After a two-stage annealing sequence, with a selective wet etch removal of the unreacted top metal stack in between, a distinct trilayered structure was formed. This trilayer was found to consist of a top layer of smaller β-FeSi2 grains of random orientation, an amorphous Ti-O-Fe-Si layer with nanocrystallites embedded, and a bottom layer of uniformly large coherently epitaxial β-FeSi2 grains. © 1995 American Institute of Physics.