EFFECTS OF SUBSTRATE-TEMPERATURE AND ANGULAR POSITION ON THE PROPERTIES OF ION-BEAM SPUTTER-DEPOSITED FE FILMS ON (100) GAAS SUBSTRATES

The effects of substrate temperature and position on the properties of Fe films deposited onto (100) GaAs substrates by ion beam sputtering were studied. Films were deposited on substrates at angular positions from -20-degrees to 66-degrees, with respect to the target surface nor mal, at temperatures from 100 to 500-degrees-C. The deposition rate wa s higher in the forward scattered direction but decreased for angles g reater than 45-degrees. The macroscopic film stress was compressive at low temperatures but underwent a compressive to tensile transition be tween 300 and 500-degrees-C. Furthermore, the stress varied with subst rate position. The stress predicted from thermal expansion mismatch is tensile. Both the low temperature compressive stress and the variatio n of stress with position are qualitatively accounted for by an energe tic bombardment or ''atomic peening'' process. For optimum deposition conditions, the films are highly (200) oriented, with rocking curves a s narrow as 0.5-degrees. The resistivity of the films approaches that of bulk Fe, and the variations of resistivity with deposition conditio ns appear to be associated with the crystallographic perfection of the films.