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Ba-122 films, which led to enormous J$_{c}$ peaks for H ‖ c . This discrepancy may originate from the different deposi- tion condition such as temperature and PLD target com- position. According to ref. $^{17}$, the Co content in Ba-122 significantly influences the superconducting properties. For instance, under-doped Ba(Fe$_{1}$$_{−}$$_{x}$Co$_{x}$)$_{2}$As$_{2}$ ( x =0.054) single crystals show a large J$_{c}$ of over 10 $^{5}$Acm $_{−}$2 at T = 0 . 7 T$_{c}$ and H$_{m}$ ( H$_{m}$ is the field of fishtail magne- tization maximum in the hysteresis loop) due to struc- tural domains, whereas the corresponding value of the over-doped crystals ( x =0.086) exhibited one order mag- nitude lower values albeit the former crystal showed a lower T$_{c}$ of 19.2 K than the latter one ( T$_{c}$ =20.5 K). The film composition in this study may be located further in the over-doped region compared with the PLD target, since Fe has been consumed during film deposition. 

In the absence of correlated defects, (i.e. if only the mass anisotropy is responsible for the J$_{c}$ anisotropy) J$_{c}$ can be scaled with H$_{eff}$ , ( H$_{eff}$ = Hϵ (Θ), ϵ (Θ) = 

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√ cos $^{2}$(Θ) + γ $^{$_{−}$2}$sin $^{2}$(Θ)), where γ is the mass anisotropy ratio. 18 This was, for instance, applied to one-band Y-123 by L. Civale et al 19 and two-band MgB$_{2}$ superconducting films in the dirty limit by S. Sen et al , 20 however, J$_{c}$ (Θ) for the latter films can not be scaled below 33 K. The scaling behavior of J$_{c}$ (Θ) as a function of H$_{eff}$ at various temperatures is exhibited in fig. 3 (b). All data except in the vicinity of H ⊥ c collapse onto a single curve with rel- atively small anisotropies, γ , of 1.5-2. This means that random defects are dominant in those regions, whereas a failure to scale the data close to H ⊥ c is owing to the intrinsic pinning, which originates from the modulation of the superconducting order parameter along the c -axis. Here, the value of the out-of-plane coherence length ξ$_{c}$ for the Co-containing Ba-122 is almost equivalent to its lattice constant c . Once the J$_{c}$ ( H$_{eff}$ ) has been obtained (i.e. collapsed data in fig. 3 (b)), J$_{c}$ owing to random de- fects can be re-plotted in the angular dependent J$_{c}$ . The solid line in fig. 3 (a) is an example at 4.2 K and µ$_{0}$H =9 T of J$_{c}$ due to random defects. 

On the other hand, J$_{c}$ (Θ) owing to the intrinsic pin- ning described above may be expressed by the Tachiki- Takahashi model (i.e. J$_{c}$ (Θ)= J$_{c}$ (180 ◦ ) | cos(Θ) | $_{−}$0 . $^{5}$).21 It is clear that the measured J$_{c}$ (Θ) in the angular region close to 90 ◦ can be fitted by this model as shown in the fig. 3 (a) (see red broken lines). 

However, the experimental data deviate from the cal- culation in the range of 100 ◦ to 110 ◦ (70 ◦ to 80 ◦ ) and this deviation becomes larger with increasing temperature or decreasing magnetic field. Plausible reasons for this de- viation may originate from either a gradual breakdown of the Tachiki-Takahashi model due to the small anisotropy or the Pearl vortices due to a thinner film thickness than the penetration depth. 22 

The angular-dependent upper critical field, H$_{c2}$ (Θ), at 21.5 K, shown in fig. 4 (a), was determined from the on- set of superconductivity defined as a 90% of the nor- mal resistance at 25 K. The resulting H$_{c2}$ (Θ) exhib- ited a maximum at Θ=90 ◦ ( H ab $_{c2}$) and a minimum at Θ=180 ◦ ( H c $_{c2}$). For comparison, we show a calcula- tion based on the anisotropic Ginzburg-Landau (GL) theory, H$_{c2}$ (Θ)= H c $_{c2}$(cos$^{2}$(Θ) + sin$^{2}$(Θ) /γ $^{2}$) $_{−}$0 . $^{5}$,with γ = H ab $_{c2}$/H c $_{c2}$. Clearly, the GL expression fits very well the measured H$_{c2}$ (Θ) similar to ref. $^{23}$, which is in contrast to the results of two-band MgB$_{2}$ superconductors in the dirty limit. 24 Shown in fig. 4 (b) is the γ values evaluated by two different methods, in which the Blatter scaling approach for the J$_{c}$ (Θ, H ) at low T , where the finite J$_{c}$ can be measured and for the H$_{c2}$ (Θ) at high T , where µ$_{0}$H$_{c2}$ < 9 T, as a function of temperature. It is clear from fig. 4 (b) that γ is increasing with increasing tem- perature, which is consistent with dominant inter-band scattering. 

In summary, we have investigated transport properties of Co-containing Ba-122 thin films deposited on insulat- ing LSAT substrates. TEM microstructural observation revealed that a thin epitaxial Fe layer was present at the film/substrate interface. Despite of the Fe layer be- 

