Rotary reactor for uniform particle coating with thin films

A reactor for coating particles, comprising:

• one or more motors;
• a rotary vacuum chamber configured to hold a plurality of particles to be coated, a cylindrical portion of the rotary vacuum chamber having an inner diameter, and wherein the rotary vacuum chamber is coupled to the one or more motors to rotate the rotary vacuum chamber in a first direction about an axial axis of the cylindrical portion of the rotary vacuum chamber;
• a vacuum port to exhaust gas from the rotary vacuum chamber;
• a paddle assembly including a rotatable drive shaft extending through the rotary vacuum chamber along the axial axis of the rotary vacuum chamber and a plurality of paddles each extending radially from the drive shaft,
• wherein the rotatable drive shaft is coupled to the one or more motors such that rotation of the drive shaft by the one or more motors orbits the plurality of paddles about the drive shaft in a second direction, wherein the plurality of paddles are equally angularly spaced about the axial axis,
• wherein the paddle assembly includes gas outlets, and
• wherein the paddle assembly includes chemical supply passages to deliver a process gas via the gas outlets into the plurality of particles;
• and
• a controller configured to cause the one or more motors to rotate the rotary vacuum chamber in the first direction about the axial axis of the cylindrical portion of the rotary vacuum chamber at a rotation speed such that a portion of the plurality of particles provide a particle bed that remains in a lower portion of the rotary vacuum chamber,
• wherein the gas outlets are positioned on the plurality of paddles at a distance from an inner surface of the rotary vacuum chamber such that, in operation as the plurality of paddles orbit, at least one gas outlet is located within the particle bed formed by the plurality of particles to percolate the process gas through the plurality of particles held within the rotary vacuum chamber.