Hey there Nadir Fadhil Habubi! Great question. When the crystallite size estimated by XRD matches the grain size for thin films, it typically means that the XRD analysis is indeed capturing the grain size accurately. In thin films, XRD can provide valuable insights into both the crystal structure and the size of the crystallites or grains within the film. When these two measurements align, it suggests that the XRD technique is effectively probing the structure of the thin film, including the grain size. So, to answer your Nadir Fadhil Habubi question directly, yes, XRD for thin films can indeed measure the grain size, and when the estimated crystallite size aligns with the observed grain size, it indicates a reliable assessment of the film's structure.

when we take XRD for mono-crystalline material.