The matching between the SEM and CLIM imaging is not as precise for the MAPI-SG sample. This is due to the grain sizes approaching the resolution limit of our technique. Consequently, grains that are larger than the resolution limit are individually resolved, while smaller grains are not, leading to multiple grains grouped into a single cluster. Notably, CLIM's resolution is higher than the diffraction limit by approximately a factor of two (see Supporting Note III). Now let us examine the correlation map and the silhouette map. In both cases, lower values are observed at the grain boundaries, with a gradual increase towards the center of the grains. The correspondence between the grains and clusters, along with a high correlation between pixels 5 within clusters (>0.7), suggests that the PL of most grains fluctuates independently from one another. However, the presence of grains with low silhouette scores suggests that not all grains are entirely independent, indicating some degree of similarity between the signals of neighboring grains. The similarity in signals between grains likely stems from a degree of communication, resulting in 10 partially similar PL fluctuations. Thus, silhouette mapping can identify specific grains that communicate with each other, even if they belong to distinct clusters. When combined, SEM and CLIM provides unprecedented levels of insight of the structurefunction relationship in semiconductors.