ADHESION OF POLYCRYSTALLINE DIAMOND THIN-FILMS ON SINGLE-CRYSTAL SILICON SUBSTRATES

Polycrystalline diamond films were deposited on (100) oriented silicon substrates using a microwave plasma disk reactor. Circular delaminations between the diamond thin film and the silicon substrate were produced by Vickers microindentation. While an overall relationship between mean delamination diameter and film thickness was not observed, an unexpectedly strong correlation was observed between delamination diameter and the square root of the coating grain size. A disadvantage of the Vickers microindentation technique is the damage sustained by the Vickers indenter tip after repeated loadings.