In order to investigate the evaporation phenomena of a small droplet on Si wafer after CMP processing, the droplet evaporation process was observed. As the result, the droplet evaporation process was categorized into constant contact radius (CCR) and constant contact angle (CCA) types. In this paper, mathematical models for droplet evaporation phenomena of CCR and CCA types were developed based on the one-dimensional diffusion equation. And the transition time from CCR to CCA was predicted using the advancing contact angle and the receding contact angle. The calculation result by model equation was compared with the experimental result.
