Investigation of Boron Nitride Prepared by Low Pressure Chemical Vapor Deposition at 650~1200 °C

• Published in: Key engineering materials 2013, Vol.537, p.58-62
• Main Authors: Su, Meng, Zhang, Li Tong, Cheng, Lai Fei, Ye, Fang, Liu, Yong Sheng, Yin, Xiao Wei
• Format: Article
• Language: English
• Subjects: Active control; Boron nitride; Carbon; Chemical vapor deposition; Coatings; Crystallization; Deposition; Low pressure
• ISSN: 1013-9826; 1662-9795; 1662-9795
• DOI: 10.4028/www.scientific.net/KEM.537.58

Boron nitride (BN) coatings were deposited on carbon substrates by low pressure chemical vapor deposition (LPCVD) in a large temperature range of 650~1200 °C, employing BCl3-NH3-H2 reaction system. The effects of depositing temperature on the yield, control step of deposition progress (deposition mechanism), microstructure, and crystallization degree of BN coating were investigated. Results show that BN deposition rate first increases and then decreases as the rising temperature and the maximum deposition rate occurs at 900~1000 °C. By the determination of the Arrenius relationship, there are three temperature regions with different active energies and controlled by different deposition mechanisms, i.e. chemical reaction, mass transport and depletion of reactants. Through the surface morphology observation by scanning electron microscopy (SEM), chemical composition analyses by energy dispersion spectroscopy (EDS) and crystallization degree and grain size comparison by Raman spectroscopy, it can be drawn that interphase-used BN is suitable to be deposited at 1000 °C.