Temperature Simulation and Diamond Deposition Behavior with Distance Between Filament and Susceptor During Hot-Filament Chemical Vapor Deposition

摘要

Diamonds were coated by hot-filament chemical vapor deposition (HFCVD) using acetone precursor in the large area with twelve rows of tantalum filaments and the length of each row being 32 cm. The deposition behavior of diamond was analyzed when the distance between filament and susceptor was varied as 6, 10, 14, 18, 22, and 26 mm. The temperature of a filament can be measured by a 2-color pyrometer; however, it is difficult to measure the temperature of the susceptor because it is located below the filament and rotated for uniform deposition of diamond. To solve this problem, numerical calculation was performed using a commercial computational fluent dynamics software, ANSYS-FLUENT. Comparison of the calculated filament temperature with the measured one showed that the error range was within 1%. Observation by field-emission scanning electron microscopy (FESEM) showed that the average particle size and thickness of the deposited diamond were the largest and the diamond quality was high when the distance was 10 mm.