The authors developed a new analysis approach for evaluation of atomic ordering in full-Heusler
alloys, which is extension of the commonly used Webster model. Our model can give accurate
physical formalism for the degree of atomic ordering in the L21 structure, including correction with
respect to the fully disordered A2 structure, i.e., the model can directly evaluate the degree of L21
ordering under a lower ordering structure than the complete B2-ordering structure. The proposed
model was applied to full-Heusler Co2FeSi alloy thin films formed by rapid thermal annealing. The
film formed at TA=800 °C showed a high degree of L21 ordering of 83% under a high degree of B2
ordering of 97%.