High purity boron nitride thin films prepared by the PDCs route

Hexagonal boron nitride (h-BN) thin films (< 10 μm) were successfully obtained on various substrates (graphite-standard and HOPG, quartz and SiC) using the preceramic polymer route. Thin films were formed using precursor solutions of poly(2,4,6-trimethylamino)borazine (polyMAB) as a source of BN. Various preparation conditions were used (i.e. solvent, precursor nature and concentration, substrate and deposition method) and their impact on final BN film quality measured. Surface morphology was observed by Scanning Electronic Microscopy (SEM) and Atomic Force Microscopy (AFM). Presence of BN material was confirmed by infrared and Raman spectroscopies and the structure observed by High Resolution Transmission Electronic Microscopy (HRTEM). The chemical composition of samples analyzed by X-ray Photoelectron Spectroscopy (XPS) gives a B/N ratio close to 1. Boron nitride films were also prepared using borazine (B3N3H6) as precursor. Initial results are presented and compared with those obtained from polyMAB solutions.