The uniformity of the film thickness in PVD depends on many parameters like uniformity of substrate, deposition rate, glancing angle and method of deposition, i.e., thermal evaporation, sputtering, laser abalation technique etc. In chemical vapour deposition, these problems are less hence the uniformity may be better. However, the situation may be case sensitive and dependent on deposition parameters.
Typically it is said that CVD gives better uniformity than PVD since CVD depends on gases that first spreads out over the surface and then deposits the film via series of chemical reactions. PVD is usually referred to as a line of sight deposition technique which means that you coat what you see and not around corners.
Of course this only holds for well optimized CVD processes. If you do it wrong you will not have good uniformity in CVD, but that is the case for any thin film technology
In both the case if the deposition parameter is suitably adjusted, you can get the very uniform film. In case of CVD, it will depend on several factor i.e. Type of reactor, electrode shape and source gas injection and shower type.
I would add to the already given answers, that it also heavily depends on the material you wish to deposit.
For PVD, you can obtain very high thickness uniformity by using appropriate rotation methods, consistent deposition rates, etc. As in most processes, consistency is critical. I have obtained < 0.1% over 300mm by designing the system geometry around the uniformity requirements (attached). I do not have equivalent experience in CVD, but I would expect the same care and consistency in system/process design are required for high-performance results.
Conference Paper Plasma-Ion-Assisted Coatings for 15-fs Laser Systems
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