Metal silicates or phosphates are deposited on a heated substrate by the
reaction of vapors of alkoxysilanols or alkylphosphates along with
reactive metal amides, alkyls or alkoxides. For example, vapors of
tris(tert-butoxy)silanol react with vapors of
tetrakis(ethylmethylamido)hafnium to deposit hafnium silicate on surfaces
heated to 300.degree. C. The product film has a very uniform
stoichiometry throughout the reactor. Similarly, vapors of
diisopropylphosphate react with vapors of lithium
bis(ethyldimethylsilyl)amide to deposit lithium phosphate films on
substrates heated to 250.degree. C. Supplying the vapors in alternating
pulses produces these same compositions with a very uniform distribution
of thickness and excellent step coverage.