2011 年 35 巻 1 号 p. 11-16
A Nano-Granular In Gap Magnetic Sensor (GIGS) constructed of both (Co-Fe)-(Mg-F) nano-granular TMR film and a yoked pair of soft magnetic films has been developed but has greater disadvantages in thermal stability than that of the TMR film itself. The authors assumed that the degradation in GIGS thermal stability was due to the inter-diffusion between TMR film and Si-O film to insulate adjacent structures in GIGS. Mg-F thin film in this study, which was the main component of the TMR film, was attempted as a barrier layer against inter-diffusion. As a result, the thermal stability of GIGS with an Mg-F thin film barrier layer was actually comparable with that of TMR film. The Auger electron spectroscopy profiles revealed that the barrier layer suppressed inter-diffusion.