Semi-continuous vapor deposition process for the manufacture of coated particles

A reactor configured for performing a single two-reagent atomic layer or molecular layer vapor phase deposition cycle on a powder, comprising:

• a powder reservoir;
• a first reactive precursor reservoir positioned below said powder reservoir;
• a second reactive precursor reservoir positioned below said first reactive precursor reservoir;
• a reactive precursor dosing system;
• a first constricted flow path flanged valve assembly operatively interposed between said powder reservoir and said first reactive precursor reservoir comprising a first valve, at least one valved inlet port in fluid communication with said first reactive precursor reservoir and said reactive precursor dosing system, at least one valved outlet port in fluid communication with said powder reservoir, said first reactive precursor reservoir or both, wherein said valved outlet port is in fluid communication with a vacuum pump for removing fluids from said powder reservoir and/or said first reactive precursor reservoir and/or producing a vacuum therein, wherein said first valve operable between an open and a closed position such that said powder reservoir is isolated from said first reactive precursor reservoir when said first valve is in the closed position but when said first valve is in the open position said first flanged valve assembly is computer controlled and is configured to allow simultaneous transfer of a powder contained within said powder reservoir into said first reactive precursor reservoir and a first reactive precursor contained within said first reactive precursor reservoir into said powder reservoir while allowing instant contact between the powder and the first reactive precursor to produce a first coated powder;
• a second constricted flow path flanged valve assembly operatively interposed between said first reactive precursor reservoir and said second reactive precursor reservoir comprising a second valve, at least one valved inlet port in fluid communication with said second reactive precursor reservoir and said reactive precursor dosing system, at least one valved outlet port in fluid communication with said first reactive precursor reservoir, said second reactive precursor reservoir or both, wherein said valved outlet port is in fluid communication with a vacuum pump for removing fluids from said first reactive precursor reservoir and/or said second reactive precursor reservoir and/or producing a vacuum therein, wherein said second valve operable between an open and a closed position such that said first reactive precursor reservoir is isolated from said second reactive precursor reservoir when said second valve is in the closed position but when the said second valve is in the open position, said second flanged valve assembly is computer controlled and is configured to allow simultaneous transfer of a powder contained within said first reactive precursor reservoir into said second reactive precursor reservoir and a second reactive precursor contained within said second reactive precursor reservoir into said first reactive precursor reservoir while allowing instant contact between the powder and a second reactive precursor to produce a second coated powder,
• wherein the powder reservoir comprises a conical section having gradually diminished cross-sections toward said first constricted flow path flanged valve assembly, wherein the first reactive precursor reservoir comprises a conical section having gradually diminished cross-sections toward said second constricted flow path flanged valve assembly, and wherein the reactor is configured to perform said atomic layer or molecular layer deposition cycle to deposit a coating of about 5 Angstroms or less on said powder having a particle size of 100 microns or less.