DEPOSITION OF CUBIC BORON-NITRIDE LAYERS - CHARACTERIZATION OF SUBSTRATE-LAYER INTERFACE

Cubic boron nitride (c-BN) layers were deposited on (111)-oriented sil icon and high-speed steel substrates in a hollow cathode are evaporati on device. The films have a maximum cubic phase content of about 95%. Film growth processes were studied ex situ in dependence on duration o f deposition by Fourier transform infrared (FTIR) transmission spectro scopy. Structure of the films was investigated by high resolution tran smission electron microscopy (HRTEM) and transmission electron diffrac tion (TED). c-BN content, ratio of the in-plane vibration (1380 cm(-1) ) to the out-of-plane vibration (780 cm(-1)) of hexagonal BN, the half -width of the phonon structures and the stress in the films are determ ined from infrared spectra. On silicon the growth sequence amorphous B N (a-BN)-hexagonal BN (h-BN)-c-BN was observed by the measuring techni ques used. An in-situ FTIR reflectance spectrometer was set up in orde r to monitor growth processes on line. In-situ reflectance measurement s on silicon and high-speed steel substrates reveal differences in the growth processes. In contrast to silicon it has been observed that on high-speed steel h-BN and c-BN grow simultaneously.