Interlaboratory Comparison of Magnetic Thin Film Measurements

A potential low magnetic moment standard reference material (SRM) was studied in an interlaboratory comparison. The mean and the standard deviation of the saturation moment m(s), the remanent moment m(r), and the intrinsic coercivity H(c) of nine samples were extracted from hysteresis-loop measurements. Samples were measured by thirteen laboratories using inductive-field loopers, vibrating-sample magnetometers, alternating-gradient force magnetometers, and superconducting quantum-interference-device magnetometers. NiFe films on Si substrates had saturation moment measurements reproduced within 5 % variation among the laboratories. The results show that a good candidate for an SRM must have a highly square hysteresis loop (m(r)/m(s) > 90 %), H(c) ≈ 400 A·m(−1) (5 Oe), and m(s) ≈ 2 × 10(−7) A·m(2) (2 × 10(−4) emu).