Plasma Enhanced Deposition of Iron and Iron Oxide Thin Films

摘要

Plasma enhanced deposition was used to form iron and iron oxide thin films from an iron pentacarbonyl source in a glow discharge, parallel plate reactor. The carbon and oxygen content of the films increased with increasing rf power. The increase in oxygen content was much greater than that of carbon, however, for films deposited at substrate temperature above 200 exp 0 C. Small crystallites (30 to 300A) of alpha -Fe and iron oxide (Fe sub 3 O sub 4 or gamma -Fe sub 2 O sub 3 ) were formed at substate temperatures of 150 exp 0 C or above. The concentration of alpha -Fe crystallites increased with increasing substrate temperature and appeared to decrease with increasing rf power. Magnetic hysteresis was observed for films deposited at temperatures above 150 exp 0 C. The coercive force ranged from 5 to 45 oersteds, increasing with both increasing substrate temperature and increasing rf power. The specific magnetization at saturation decreased from 2 to 0.4 weber-meter/kilogram by increasing the rf power from 10 to 100 watts. Square hysteresis loops (B/sub r//B/sub s/ approx. = 1) were observed for a substrate temperautre of 300 exp 0 C and rf power levels above 30 watts. The magnetization, M Vector, was found to lie in the film plane. (ERA citation 05:026121)