Whole wafer magnetostriction metrology for magnetic films and multilayers

C B Hill, W R Hendren, R M Bowman, P K McGeehan, M A Gubbins, V A Venugopal

Research output: Contribution to journalArticlepeer-review

11 Citations (Scopus)
719 Downloads (Pure)


The requirements for metrology of magnetostriction in complex multilayers and on whole wafers present challenges. An elegant technique based on radius of curvature deformation of whole wafers in a commercial metrology tool is described. The method is based on the Villari effect through application of strain to a film by introducing a radius of curvature. Strain can be applied tensilely and compressively depending on the material. The design, while implemented on 3'' wafers, is scalable. The approach removes effects arising from any shape anisotropy that occurs with smaller samples, which can lead to a change in magnetic response. From the change in the magnetic anisotropy as a function of the radius, saturation magnetostriction ?s can be determined. Dependence on film composition and film thickness was studied to validate the radius of curvature approach with other techniques. ?s decreases from positive values to negative values through an increase in Ni concentration around the permalloy composition, and ?s also increases with a decrease in film thickness, in full agreement with previous reports. We extend the technique by demonstrating the technique applied to a multi-layered structure. These results verify the validity of the method and are an important step to facilitate further work in understanding how manipulation of multilayered films can offer tailored magnetostriction.
Original languageEnglish
Article number045601
JournalMeasurement Science and Technology
Issue number4
Early online date01 Mar 2013
Publication statusPublished - Apr 2013

ASJC Scopus subject areas

  • Applied Mathematics
  • Instrumentation


Dive into the research topics of 'Whole wafer magnetostriction metrology for magnetic films and multilayers'. Together they form a unique fingerprint.

Cite this