GROWTH OF ALPHA'-NITROGEN MARTENSITE AND FE16N2 FILMS USING (001)SILICON SUBSTRATES

In this work, epitaxial, single-phase (001) textured alpha' nitrogen-m artensite films have been grown successfully on (001) Si substrates wi th a Ag reaction-barrier layer using conventional reactive sputtering. The growth orientation was obtained by X-ray phi-scans: (001)\\alpha' (001)//Si[100]\\Ag[100]\\alpha'[110]. In addition, (001) textured Fe16 N2 or alpha '' nitrogen-martensite which forms from an ordering of the N atoms in the alpha', was detected in the films after ex-situ anneal ing. High resolution electron microscopy studies reveal that alpha' ma rtensite has good epitaxy with the Ag underlayer. Single-crystal forma tion of the martensites, however, is impeded by the intersection of Ag twins with the Ag/Fe-N interface. Single phase alpha '' was not detec ted in any of the as-deposited films grown under various substrate tem peratures (10-150 degrees C) and pressures (2-5mTorr).