Abstract: A method of providing a reagent into a chemical process said provision being in the vapor phase and at a controlled mass flow rate wherein the method comprises:(a) providing a gas stream which contains a gaseous phase complexing agent for the reagent said complexing agent being provided at a controlled partial vapor pressure in said gas stream;(b) providing a primary source of the reagent in a reservoir which is connected to the gas stream via a diffusion path;(c) causing the gaseous phase complexing agent to diffuse into the reservoir at a mass flow rate controlled by its partial pressure in the gas stream;(d) causing the gaseous phase complexing agent in the reservoir to react with the primary source to generate a gaseous phase complex of the reagent and the gaseous phase complexing agent, said generation being, in the steady state, at a rate equivalent to the rate of inflow of said complexing agent;(e) causing the gaseous phase complex to diffuse out of the reservoir into the gas stream at a rate, in the s

Abstract: In the deposition of metal on solid substrates by a Metal Organic Chemical Deposition process, an improvement comprises the provision of vapors of a precursor of the metal by passing an inert carrier gas through a mixture of the metal precursor and a liquid having a vapor pressure at ambient temperature lower than that of the metal precursor and in which the metal precursor is at least partially soluble.

Abstract: A method for forming a layer of a Group II or III fluoride on a semiconductor substrate (e.g. as epitaxial insulating layer) comprising vaporizing a precursor (I), where M is Be, Ca, Sr, Ba or lanthanide, b and d are 0 or 1. A, B, C and D are independently (IIA) or (IIB), X being O, S, NR, PR where R is H, alkyl, perfluoroalkyl; Y is perfluoroalkyl, fluoroalkenyl, fluoroalkylamine or fluoroalkenylamine; Z is H, F, alkyl, perfluoroalkyl or perfluoroalkenyl; and then decomposing the precursor vapor to form M fluoride. A preferred precursor for calcium fluoride is calcium 1,1,1,5,5,5-hexafluor-2,4-pentanedione complex where b and d are 0.