MICROSTRUCTURES OF DIAMOND FILMS DEPOSITED ON (100) SILICON-WAFER BY MICROWAVE PLASMA-ENHANCED CHEMICAL VAPOR-DEPOSITION

Abstract

Diamond films were deposited on (100) 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 (111) to the (100) plane with increase in the methane concentration due to the decreased adatom mobility. The morphology also changed from (111) to (100) planes with substrate temperature, due to the effect of the increased chemical species. The change in the crystallinity with deposition time was also investigated.