Instability and morphology of thin liquid films on chemically heterogeneous substrates

A new mechanism for the surface instability and dewetting of thin films on chemically heterogeneous substrates is identified and simulated. The time s cale for instability varies inversely with the potential difference due to the heterogeneity. Heterogeneities can even destabilize spinodally stable f ilms, reduce the time of rupture substantially for thicker films, and produ ce complex and locally ordered morphological features (e.g., ripples and ca stle-moat structures, lack of undulations before hole formation) that are n ot predicted by the spinodal mechanism.