In this paper we describe the growth of silicon nitride from nitrogen and silane for the first time by capacitively coupled remote PECVD. We report on the effect of process parameters on the composition and properties of the deposited films and we show that by adjustment of these parameters it is possible to produce high-quality material which could be of interest for electronic applications. Of particular note is that the growth rate is about one order of magnitude higher than any previously reported for nitride growth with remote PECVD using molecular nitrogen as the nitrogen source. We also discuss the mechanism of growth and propose that electron excitation of nitrogen and silane occurs in the gas phase, producing SiHx species which are adsorbed on the growing surface. The nitrogen is then incorporated into the layer by heterogeneous reaction. -

The previously reported varying CVD deposition rates obtained when using the new precursor [Ba(TDFND)J have been investigated using a range of techniques for analysing hydrated and anhydrous forms of the precursor before and after use for deposition. It is shown that, apart from water loss from the hydrate, there are no significant molecular structural changes to the precursor in use. X-Ray powder diffractograms do show, though, that there is the possibility of crystalline growth, and the implications of this are discussed. A simple model of spherical crystallites coalescing is considered, and it is shown that the range of behaviour observed in practice with solid precursors can be satisfactorily explained by the model. When full cognisance is taken of the effects of precursor purity and degree of crystallinity it is found to be possible to grow reproducibly high-quality BaF, and superconducting YBCO. The precursor [Ba(TDFND)J is thus a potentially useful new material for MOCVD of YBCO and other barium-containing films.

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A new highly volatile Ba-containing precursor which is thermally stable at I atm (101325 Pa) pressure is described. This precursor, which is a bis(P-diketonate) that has only C3F, as substituent groups and which is coordinated with the polyether tetraglyme, is shown to have reproducible carry-over rates and to give repeatable deposition rates for the chemical vapour deposition (CVD) of highly oriented crystalline BaF,. It has also been shown to be suitable for use in the preparation of superconducting YBCO films. Measurements of thermodynamic and kinetic parameters have been made and are compared with those obtained with other Ba-containing precursors. It is concluded that the new Ba-containing precursor is potentially a very promising material for the preparation of superconducting YBCO films.

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