The paraconductivity of a number of c-axis-oriented YBa2Cu3Ox thin films, with a range of c-axis lattice parameters and Tc-values, has been determined as a function of temperature and analysed in terms of the paraconductivity due to direct and indirect fluctuation contributions. We present results on the c-axis coherence length and the phase-relaxation time at 100 K obtained from the fit to the paraconductivity data. The paraconductivity results for optimally doped films were: c-axis coherence length: ξc(0) = 1.25 Å; pair-breaking parameter: δ = 0.05; phase-relaxation time at 100 K: τϕ = 0.066 ps; and two-three-dimensional crossover temperature: T+ = 96.6 K. These values are in good agreement with those from other published work. There was considerable scatter in the coherence length and phase-relaxation time for films with different critical temperatures and oxygen contents. These results were process dependent but appear to be related to the 60 K phase transition in the Tc-x phase diagram.

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