Title :
A tunneling magnetoresistance sensor overlaid with a longitudinal bias stack in a read region
Author :
Tsann Lin ; Mauri, Daniele ; Ty Chen ; Wolfman, J.
Author_Institution :
IBM Almaden Res. Center, San Jose, CA, USA
Abstract :
Summary form only given. A tunneling magnetoresistance (TMR) sensor overlaid with a longitudinal bias (LB) stack in a read region is characterized in this study. The TMR sensor comprises Pt-Mn/Co-Fe/Ru/Co-Fe/Al-O/Co-Fe/Ni-Fe films, and the LB stack comprises Co-Fe/AFM (Ir-Mn or Pt-Mn) films. The Pt-Mn film of the TMR sensor is used to transversely pin its adjacent Co-Fe film and induce a transverse flux closure between the two Co-Fe films adjacent to the Ru film, thereby achieving proper sensor operation. The net moments of the two Co-Fe films (m/sub 2/-m/sub 3/) are optimized in order to induce an optimal demagnetizing field for optimal TMR responses. The AFM film of the LB stack is used to longitudinally pin its adjacent Co-Fe film and induce a longitudinal flux between the Co-Fe film and the Co-Fe/Ni-Fe sense layers, thereby achieving sensor stabilization. The moment ratio of the Co-Fe longitudinal-pinned layer to the Co-Fe/Ni-Fe sense layers (m/sub 4//m/sub 1/) is optimized in order to achieve sensor stability while maintaining high signal sensitivity.
Keywords :
antiferromagnetic materials; demagnetisation; magnetic flux; magnetic heads; magnetic moments; magnetic multilayers; magnetic sensors; magnetic thin films; optimisation; stability; tunnelling magnetoresistance; CoFe-IrMn; CoFe-IrMn films; CoFe-PtMn; CoFe-PtMn films; LB stack; Pt-Mn/Co-Fe/Ru/Co-Fe/AlO/Co-Fe/Ni-Fe films; PtMn-CoFe-Ru-CoFe-AlO-CoFe-NiFe; TMR sensors; adjacent film longitudinal pinning; adjacent film transverse pinning; antiferromagnetic film; film net moment optimization; longitudinal-pinned layer moment ratio; optimal TMR responses; optimal demagnetizing field; read region longitudinal bias stack overlay; sense layer longitudinal flux; sense layers; sensor stability; sensor stabilization; signal sensitivity; transverse flux closure inducement; tunneling magnetoresistance sensors; Demagnetization; Electrical resistance measurement; Influenza; Iron; Magnetic sensors; Propulsion; Sensor phenomena and characterization; Stability; Testing; Tunneling magnetoresistance;
Conference_Titel :
Magnetics Conference, 2002. INTERMAG Europe 2002. Digest of Technical Papers. 2002 IEEE International
Conference_Location :
Amsterdam, The Netherlands
Print_ISBN :
0-7803-7365-0
DOI :
10.1109/INTMAG.2002.1000947
