Method for delivering an involatile reagent in vapor form to a CVD reactor

Claim 1

A process for delivering an involatile solid source reagent material having a vapor pressure of less than about 0.1 torr at 25° C. and 1 atmosphere conditions, and which is thermally unstable at its vaporization temperature, as a source regent material vapor into a CVD reactor, said process comprising: providing a supply vessel containing a reagent source liquid formed by dissolving the involatile solid source reagent material in a non-azotropic organic solvent, wherein the reagent source liquid is contained in the supply vessel in a non-heated state, at or below room temperature; arranging a flash vaporization structure comprising a foraminous element having a surface-to-volume ratio of at least 4, in liquid flow communication with the supply vessel containing the reagent source liquid; heating the foraminous element to a flash vaporization temperature for the involatile solid source reagent material; and flowing the reagent source liquid from the supply vessel to the heated foraminous element, with the reagent source liquid in a non-atomized state directly issuing a liquid stream of the reagent source liquid onto the heated foraminous element, and flash vaporizing the involatile solid source material from the reagent source liquid to form the source reagent material vapor.

Claim 24

A method of forming a composite article comprising a silicon or gallium arsenide substrate comprising: forming on the silicon or gallium arsenide substrate a graded epitaxial layer comprising at least two metal fluorides selected from the group consisting of barium fluoride, calcium fluoride, and strontium fluoride by CVD using metal involatile solid source reagent compounds therefor, wherein the metal involatile solid source reagent compounds are supplied in a source reagent compounds vapor, by a process comprising: dissolving each of the involatile solid source reagent compounds, which are thermally unstable at their vaporization temperatures, in a non-azeotropic organic solvent to form a reagent source liquid, wherein the reagent source liquid is maintained in a non-heated state, at or below room temperature; providing a foraminous element having a surface-to-volume ratio of at least 4; heating the foraminous element to a flash vaporization temperature for the involatile solid source reagent compounds; and flowing reagent source liquid in a non-atomized state as a liquid stream onto the heated foraminous element, and flash vaporizing the involatile solid source reagent compounds from the reagent source liquid to form the source reagent compounds vapor; and forming on the graded metal fluoride epitaxial layer an overlayer of a material selected from the group consisting of silicon, gallium arsenide, and copper oxide HTSC materials, with the proviso that the overlayer material is different from the material of the substrate.

Claim 25

A method of forming a composite article comprising a silicon or gallium arsenide substrate comprising: forming on the silicon or gallium arsenide substrate a graded epitaxial layer comprising at least two metal fluorides selected from the group consisting of barium fluoride, calcium fluoride, and strontium fluoride by CVD using metal involatile solid source reagent compounds therefor, wherein the metal involatile solid source reagent compounds are supplied in a source reagent compounds vapor, by a process comprising: dissolving each of the involatile solid source reagent compounds, which are thermally unstable at their vaporization temperatures, in a non-azeotropic organic solvent to form a reagent source liquid, wherein the reagent source liquid is maintained in a non-heated state, at or below room temperature; providing a foraminous element having a surface-to-volume ratio of at least 4; heating the foraminous element to a flash vaporization temperature for the involatile solid source reagent compounds; and flowing reagent source liquid in a non-atomized state as a liquid stream onto the heated foraminous element, and flash vaporizing the involatile solid source reagent compounds from the reagent source liquid to form the source reagent compounds vapor; and forming on the graded metal fluoride epitaxial layer an overlayer of a material selected from the group consisting of silicon, gallium arsenide, and copper oxide HTSC materials, with the proviso that the overlayer material is different from the material of the substrate.