Dc conductivity and Hall effect measurements were performed on Cu-GeO2 thin films with the aim of obtaining information about dc conduction mechanism. The conductivity results reveal that the activation energy is temperature dependent, increasing significantly above a btransition temperature Tt. Hall mobility showed a sign reversal around Tt, above which it increased with increasing temperature reaching a maximum at a critical temperature Tc. Above Tt, the conductivity is best described by small polaron hopping model. Below Tt, the Hall mobility shows a significant rise with decreasing temperature, indicating polaronic band conduction mechanism. Various parameters associated with polaronic formation are calculated.
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