Influence of process parameters on the growth of TiN in different sized plasma-assisted chemical vapor deposition reactors

TiN layers were deposited by pulsed d.c. plasma in an Ar-H-2-N-2-TiCl4 mixt ure on substrates positioned on the cathode in different-sized plasma-assis ted chemical vapor deposition reactors. We investigated the influence of di fferent N-2-H-2 gas flow and of the pause time on the layer properties in r elation to the reactor volume. Scanning electron microscopy measurements sh ow that the growth rate increases with increasing N-2/H-2 gas flow ratio, w hereas an influence from the total gas flow cannot be found. The TiN layers are nearly stoichiometric, except for low N-2 gas flows. Grazing incidence X-ray diffractometry measurements reveal a transition from X-ray amorphous to crystalline TiN with higher N-2/H-2 gas how ratios. However, a preferre d orientation was not observed. The decrease of the pause time at pulses with the same current height and o n-time lead to a strong decrease of the effective growth rate. We assume th at a sufficient pause length is necessary for a stable growth of TiN layers . (C) 1999 Published by Elsevier Science S.A. All rights reserved.