Reactor for coating particles in stationary chamber with rotating paddles and gas injection
A reactor for coating particles includes a stationary vacuum chamber that has a lower portion that forms a half-cylinder and an upper portion and that holds a bed of particles to be coated, a vacuum port in the upper portion of the chamber, a paddle assembly, and a gas injection assembly that includes a vaporizer to convert a first liquid to a first reactant or precursor gas, a manifold to receive the first reactant or precursor gas from the vaporizer, and a plurality of channels leading from the manifold to a plurality of apertures located in the lower portion of the chamber.
1 . A reactor for coating particles, comprising:
a stationary vacuum chamber to hold a bed of particles to be coated, the chamber having a lower portion that forms a half-cylinder and an upper portion;
a vacuum port in the upper portion of the chamber;
a paddle assembly including a rotatable drive shaft extending along an axial axis of the half-cylinder and a plurality of paddles extending radially from the drive shaft such that rotation of the drive shaft by a motor orbits the plurality of paddles about the drive shaft inside the vacuum chamber; and
a gas injection assembly including
a first plurality of apertures arranged in a first row and extending through a wall of the lower portion of the stationary vacuum chamber and to an inner surface of the half-cylinder to inject a first reactant or precursor gas into the lower portion of the vacuum chamber,
a second plurality of apertures arranged in a second row parallel to and vertically offset from the first row and extending through the wall of the lower portion of the stationary vacuum chamber and to the inner surface of the half-cylinder to inject a second reactant or precursor gas into the lower portion of the vacuum chamber.
2 . The reactor of claim 1 , wherein the first row and the second row extend along the axial axis.
3 . The reactor of claim 2 , wherein first plurality of apertures and the second plurality of apertures are configured such that the first reactant or precursor gas and the second reactant or precursor gas are injected into the vacuum chamber substantially tangent to a curvature of the inner surface of the half-cylinder formed by the lower portion.
4 . The reactor of claim 1 , wherein the first plurality of apertures and second plurality of apertures are positioned in a lower half of the lower portion of the vacuum chamber.
5 . The reactor of claim 4 , wherein the first plurality of apertures and second plurality of apertures are positioned in a lower quarter of the lower portion of the vacuum chamber.
6 . The reactor of claim 1 , comprising
a vaporizer configured to convert a first liquid received from a fluid source into the first reactant or precursor gas,
a manifold including a gas distribution chamber and a first inlet aperture coupling the vaporizer to the gas distribution chamber, wherein the gas distribution chamber has a width along a longitudinal first axis of the drive shaft and a height along a second axis perpendicular to the longitudinal first axis and the first inlet aperture is narrower than the gas distribution chamber along the first axis and the second axis, and
a plurality of channels leading from the manifold to the first plurality of apertures.
7 . The reactor of claim 6 , wherein the manifold and plurality of channels are formed in a unitary body.
8 . The reactor of claim 7 , wherein the body is a side wall of the vacuum chamber.
9 . The reactor of claim 6 , comprising a passage to deliver an inert gas to the gas injection assembly.
10 . The reactor of claim 9 , wherein the manifold further includes a second inlet aperture coupling the passage to the gas distribution chamber.
11 . The reactor of claim 10 , wherein the second inlet aperture is narrower than the gas distribution chamber along the first axis and the second axis.
12 . The reactor of claim 6 , wherein the vaporizer includes a cavity, a heater to heat walls of the cavity, and a nozzle to aerosolize the first liquid as the first liquid passes into cavity.
13 . The reactor of claim 6 , wherein each channel of the plurality of channels further has a restriction between the manifold and a respective aperture of the plurality of apertures.
14 . The reactor of claim 6 , wherein the vaporizer is immediately adjacent the manifold.
15 . The reactor of claim 1 , further comprising a controller configured to keep a flow rate of the reactant or precursor gas flow sufficiently slow that powder stays in the bed of particles.