Microstructures of diamond films deposited on (100) silicon wafer by microwave plasma-enhanced chemical vapour deposition

Abstract

Diamond films were deposited on (1 0 0) silicon wafer by microwave plasma-enhanced chemical vapour deposition. The microstructural changes of the diamond films were studied in relation to the pre-treatment of the silicon substrate, the methane concentration and the substrate temperature. The ultrasonic method for the pre-treatment of the silicon substrate increased the nucleation density, resulting in the deposition of small diamond particles. The surface morphology changed from the close-packed (1 1 1) to the (1 0 0) plane with increase in the methane concentration due to the decreased adatom mobility. The morphology also changed from (1 1 1) to (1 0 0) planes with substrate temperature, due to the effect of the increased chemical species. The change in the crystallinity with deposition time was also investigated.