反応性プラズマを用いたＦｅ１６Ｎ２薄膜の合成

Abstract

Fe16N2 films (with a thickness of 3000A) were fabricated on MgO (001) substrates by the conventional DC facing targets sputtering method with a controlled reactive plasma, with an electron temperature of Te=0.3eV, an electron density of Ne=1×1010cm-3, a deposition rate of 200A/min and an N2 flow ratio ranged from 10% to 20%. In an as-deposited state, α′ single phases with various nitrogen contents were formed. After annealing at 150°C for 2 hours, an α″ phase (≅11 at%N) and an α′ phase (11.1 at%N and 1∼2 at%N) were formed. Ms showed nearly the same value as α-Fe (2.2T), despite the existence of the α″ phase. The lattice constant c in the α″ phase in the present films agreed well with the value reported by Jack; however, the values of the lattice constant a in the present films were about 1∼3% smaller than Jack’s value. The unit cell volumes in the α″ phase in the present films were 192.5∼202.6A3, about 1.4∼6.3% less than Jack’s value of 20.5A3.