INITIAL GROWTH-PHASE OF DIAMOND THIN-FILMS OBSERVED BY THERMAL EMISSION-SPECTROMETRY

Pyrometric interferometry has been performed in the formation of diamo nd crystals and films synthesised on pretreated single silicon substra tes by a microwave plasma assisted chemical vapour deposition (MPCVD) technique. The growth mode of this material induces particular variati ons of the emissivity ratio epsilon/epsilon(0) that we an able to simu late theoretically, taking into account the nucleation mode (Volmer-We ber), the nucleation density N and the growth rate nu of the diamond c rystallites. The comparison between the experimental and the theoretic al curves of the epsilon/epsilon(0) variations allows us to understand better the first stage of the CVD diamond formation in terms of kinet ic and nucleation density. Finally, the real-time monitoring of these parameters is a very attractive objective for the precise control of t he deposition process, for which the first stages are crucial for the subsequent diamond film quality. (C) 1997 Elsevier Science S.A.