Efficient Approach to Measure Crystallization Temperature in Amorphous Thin Film by Infrared Reflectivity

  • Wang, Wenxiu (Department of Electronic Engineering, Graduate School of Engineering, Tohoku University) ;
  • Saito, Shin (Department of Electronic Engineering, Graduate School of Engineering, Tohoku University) ;
  • Yakabe, Hidetaka (Metallurgical Research Laboratory, Hitachi Metals, Ltd.) ;
  • Takahashi, Migaku (New Industry Creation Hatchery Center, Tohoku University)
  • 투고 : 2012.10.18
  • 심사 : 2013.05.09
  • 발행 : 2013.06.30


This paper shows a new effective approach to measure crystallization temperature of soft magnetic underlayer (SUL) for next generation of heat assisted perpendicular recording media. This approach uses temperature dependent reflectivity, which shows a clear jump when samples are crystallized. To achieve this measurement, an optical system is set up using hot plate and infrared laser. Reflectivity of SUL $(Co_{70}Fe_{30})_{92}Ta_3Zr_5$ shows a clear jump at its amorphous-crystalline transition temperature. Experiment results show this effect is clear in infrared region, and is weak for visible light.


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