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Zn1-xFex O inhomogeneous oxide magnetic semiconductor films with high Fe concentration are prepared by sput-tering, and fast annealing is carried out at different temperatures. It is found that magnetic properties are greatly modulated by controlling the composition inhomogeneity and subsequently fast annealing. Both ferromagnetic and paramagnetic components are found to coexist in the as-deposited Zn1-xFex O magnetic semiconductor. In particular, the antiferromagnetic coupling between the neighbouring local ferromagnetic regions is found in the as-deposited Zn0.23Fe0.77O film, and the antiferromagnetic coupling strength increases with increasing temper-ature from 110K to 30OK. We believe that this unusual antiferromagnetic coupling is mediated by thermally activated hopping carriers.