A new insight into LPCVD of refractory metals (W and Mo) deposited by silicon reduction of their fluorides.

We present a comparative study of Low Pressure Chemical Vapor Deposition (LPCVD) of the refractory metals W and Mo on silicon substrates by the silicon reduction of their fluorides WF sub 6 and MoF sub 6. Our results contribute a new insight into the LPCVD process. The processes of W and Mo deposition follow a very similar course, as indicated by the similarity of the deposits; both films are porous, and their interfaces with silicon have identical texture. Moreover, from experiments with excess SiF sub 4, even the intermediate reactions contributing to the deposition process seem to follow similar steps.