Scratch tests were done on Si-C-N coatings developed on Si (100) substrates useful for MEMS devices in unconducive environments. The interfacial adhesive strength got manifested in different failure morphologies. The features depicting their chronological failures were analyzed by relating the load-scratch length plots with the scratch track image. The cohesive and adhesive strength were found to be independent to each other with each of them getting manifested in different ways.