A Study in Developments of Hot Filament Chemical Vapor Deposition System for Diamond Films Growth Process

• Main Authors: Tai-Jun Wang, 王泰鈞
• Other Authors: 林啟瑞
• Format: Others
• Online Access: http://ndltd.ncl.edu.tw/handle/9ju559

碩士 === 國立臺北科技大學 === 製造科技研究所 === 104 === The purpose of this thesis is to develop a home-made hot filament chemical vapor deposition (HFCVD) system for fabrication of diamond films on silicon and cobalt cemented tungsten carbide (WC-Co) substrates. Aiming at improvement of filament lifetime as well as reproducibility, filament modules have been designed and optimized with diameter, tensile loading, and pretreatment procedures. The diamond film growth processes were investigated and controlled by CH4:H2 concentration rate, working pressure, substrate-filament distance, and substrate temperature. Our data indicates that microcrystalline diamond (CVD) and nanocrystalline diamond (NCD) films were successfully growth on Si substrate which possess high uniformity and quite low surface roughness of 12.7 nm and 3.67 nm (rms), respectively. Besides, as the fabrication of diamond films on cemented WC-Co substrate is well-known to be challenged by high processing temperature, poor adhesion and uniformity, thus hindering the feasible applications of diamond coatings in manufacturing fields. Therefore, in this paper, we also focused on development in scalable fabrication of diamond coating on WC-Co substrate with complete procedures including of substrate surface pretreatment, diamond nucleation, and diamond film depositions. The data reveals that the diamond coatings were deposited WC-Co substrate under relatively low substrate temperature of 500 oC whereby possessing a highly crystallinity and good adhesion. The achievements of the thesis indicate a prospect of fabrication of diamond coating on low melting temperature substrate as well as applications of diamond-based devices.