Apparatus and method for depositing large area coatings on non-planar surfaces

A common reactant gas injector for injecting at least one reactant gas by differential flow into a plurality of plasmas generated by an array of a plurality of plasma sources such that a first flow rate of said reactant gas into a first plasma generated by a first plasma source in said array is different from a second flow rate of said reactant gas into a second plasma generated by a second plasma source in said array, said reactant gas injector comprising:

• a) at least one reactant gas inlet comprising a tubular-walled structure having an interior space through which said at least one reactant gas is supplied from a reactant gas source;
• b) a first plurality of orifices proximate to said first plasma, each of said first plurality of orifices extending through said tubular-walled structure from said interior space to an outer surface of said reactant gas inlet, wherein said first plurality of orifices is oriented such that said at least one reactant gas passes from said interior space through said first plurality of orifices and is directed into said first plasma at said first flow rate;
• and
• c) a second plurality of orifices proximate to said second plasma, each of said second plurality of orifices extending through said tubular-walled structure from said interior space to an outer surface of said at least one reactant gas inlet, wherein said second plurality of orifices is oriented such that said at least one reactant gas passes from said interior space through said second plurality of orifices and is directed into said second plasma at said second flow raze, said second flow rate being different from said first flow rate, such that said plurality of plasmas impinges upon a first region of a surface of a non-planar substrate and a second region of said surface of said non-planar substrate to form a coating of substantially uniform thickness, wherein said first region is located at a first working distance from said plurality of plasma sources and said second region is located at a second working distance from said plurality of plasma sources, said first working distance being greater than said second working distance.

An apparatus for depositing a uniform coating on surface of a non-planar substrate, said apparatus comprising:

• a) at least one array of a plurality of plasma sources for generating a plurality of plasmas, wherein at least one of said plurality of plasma sources is an expanding thermal plasma source, wherein each of said plurality of plasma sources includes a cathode, an anode, and an inlet for a non-reactive plasma source gas disposed in a plasma chamber which is maintained at a first predetermined pressure;
• b) a deposition chamber for containing said non-planar substrate, wherein said deposition chamber is in fluid communication with said plasma chamber, and wherein said deposition chamber is maintained at a second predetermined pressure said second predetermined pressure being less than said first predetermined pressure;
• and
• c) at least one common reactant gas injector disposed in said deposition chamber for injecting at least one reactant gas by differential flow into said plurality of plasmas such that a first flow rate of said at least one reactant gas into a first plasma generated by a first plasma source in said at least one array is different from a second flow rate of said at least one reactant gas into a second plasma generated by a second plasma source in said at least one array, said at least one reactor injector comprising:
• (i) at least one reactant gas inlet comprising a tubular-walled structure having an interior space through which said at least one reactant gas is supplied from a reactant gas source;
• (ii) a first plurality of orifices proximate to said first plasma, each of said first plurality of orifices extending through said tubular-walled structure from said interior space to an outer surface of said reactant gas inlet, wherein said first plurality of orifices is oriented such that said at least one reactant gas passes from said interior space through said first plurality of orifices and is directed into said first plasma at a first flow rate;
• and (iii) a second plurality of orifices proximate to said second plasma, each of said second plurality of orifices extending through said tubular-walled structure from said interior space to an outer surface of said at least one reactant gas inlet, wherein said second plurality of orifices is oriented such that said at least one reactant gas passes from said interior space through said second plurality of orifices and is directed into said second plasma at a second flow rate such that said plurality of plasmas impinges upon a first region of said surface of said non-planar substrate and a second region of said surface of said non-planar substrate to form a coating of substantially uniform thickness, wherein said first region is located at a first working distance from said plurality of plasma sources and said second region is located at a second working distance from said plurality of plasma sources, said first working distance being greater than said second working distance.