DIAMOND DEPOSITION AT VARIOUS DISTANCES FROM FILAMENT IN JET FLOW HFCVD

Modifications in the conventional HFCVD diamond deposition technique, incorporating jet flow, are described. Contrary to the conventional HF CVD technique where filament to substrate distance has to be restricte d to approximately 1 cm, in the modified version this distance could b e increased upto approximately 8 cm. The effect of variation of substr ate to filament distance on the morphology, quality and rate of diamon d deposition has been described. The role of convectional flow of feed gases together with special pretreatment, high flow rate of input gas es and application of electric field has been brought out.