Matrix-controlled printhead grid control for an electrochemical additive manufacturing system
Process for manufacturing a printhead for a 3D manufacturing system that uses metal electrodeposition to construct parts. The printhead may be constructed by depositing layers on top of a backplane that contains control and power circuits. Deposited layers may include insulating layers and an anode layer that contain deposition anodes that are in contact with the electrolyte to drive electrodeposition. Insulating layers may for example be constructed of silicon nitride or silicon dioxide; the anode layer may contain an insoluble conductive material such as platinum group metals and their associated oxides, highly doped semiconducting materials, and carbon based conductors. The anode layer may be deposited using chemical vapor deposition or physical vapor deposition. Alternatively in one or more embodiments the printhead may be constructed by manufacturing a separate anode plane component, and then bonding the anode plane to the backplane.
1. A matrix-controlled printhead for an electrochemical additive manufacturing system, comprising:
a deposition grid partitioned into grid regions along an x-axis direction and along a y-axis direction, said deposition grid comprising:
a grid x resolution defined as a number of grid regions along the x-axis direction;
a grid y resolution defined as a number of grid regions along the y-axis direction;
a grid x pitch defined as a length of a grid region of said grid regions along the x-axis direction;
a grid y pitch defined as a length of a grid region of said grid regions along the y-axis direction;
a grid pitch defined as a minimum of said grid x pitch and said grid y pitch; and
a grid region area defined as a geometric area of said grid region;
a grid control circuit comprising:
an array of row traces;
an array of column traces;
a row driver circuit coupled electrically to said row traces; and
a column driver circuit coupled electrically to said column traces;
a power distribution circuit; and
an array of deposition elements aligned with said deposition grid, each deposition element of said array of deposition elements corresponding to a unique grid region of said grid regions, wherein said each deposition element comprises:
a deposition anode comprising:
a conductive material;
an exposed surface comprising said conductive material wherein said exposed surface is configured to contact an electrolyte; and
a conductive path through said deposition anode to said exposed surface;
a deposition control circuit coupled electrically to:
said deposition anode;
an associated row trace of said row traces;
an associated column trace of said column traces;
said power distribution circuit; and
one or more insulating layers between said deposition control circuit and said electrolyte,
wherein:
said deposition control circuit controls an amount of current flowing through said conductive path of said deposition anode; and
when said exposed surface is placed in contact with said electrolyte, and when said current flows through said conductive path, said current causes an electrochemical deposition reaction on a cathode.
2. The system of claim 1 , wherein said deposition control circuit of each deposition element of said array of deposition elements, said power distribution circuit of each deposition element of said array of deposition elements, and said deposition anode of each deposition element of said array of deposition elements are configured to supply between 0 and 100 milliamps of said current per square centimeter of said grid region area through said conductive path of said each deposition element of said array of deposition elements when said deposition control circuit of said each deposition element of said array of deposition elements sets said amount of current flowing through said conductive path of said each deposition element of said array of deposition elements to said maximum current level.
3. The system of claim 1 , wherein said deposition control circuit of each deposition element of said array of deposition elements comprises:
a first switching element controlled by said associated row trace; and
a second switching element controlled by said associated column trace when said first switching element is active,
wherein said second switching element controls said amount of current flowing through said conductive path of said deposition anode of each deposition element of said array of deposition elements.
4. The system of claim 3 , wherein said first switching element and said second switching element are transistors.
5. The system of claim 4 , further comprising a non-glass substrate, wherein said first switching element and said second switching element are deposited onto the non-glass substrate.
6. The system of claim 5 , wherein said transistors comprise silicon.
7. The system of claim 5 , wherein said transistors comprise indium gallium zinc oxide.
8. The system of claim 1 , wherein a length of said conductive path of said deposition anode of each deposition element of said array of deposition elements is at least 10% of said grid pitch.
9. The system of claim 1 , wherein said deposition anode of each deposition element of said array of deposition elements further comprises one or more layers of said conductive material above said deposition control circuit of said each deposition element of said array of deposition elements.
10. The system of claim 1 , wherein said conductive material of said deposition anode of each deposition element of said array of deposition elements comprises one or more of platinum group metals and their associated oxides, highly doped semiconducting materials, and carbon nanotubes.
11. The system of claim 1 , wherein said power distribution circuit comprises a lattice of conductive power traces aligned with said deposition grid, wherein said conductive power traces are electrically coupled to one another at points where said lattice of conductive power traces cross.
12. The system of claim 1 , wherein said power distribution circuit comprises power supply connections on two or more sides of said deposition grid.
13. The system of claim 1 , wherein said power distribution circuit comprises a substantially solid plane of conductive material.
14. The system of claim 1 , wherein said deposition anode of each deposition element of said array of deposition elements further comprises one or more sections extending horizontally along a horizontal axis parallel to said deposition grid and covered by said one or more insulating layers of said each deposition element of said array of deposition elements.
15. The system of claim 1 , wherein an area of said exposed surface of said deposition anode of each deposition element of said array of deposition elements is at least 15% of said grid region area.
16. The system of claim 1 , wherein said matrix-controlled printhead is configured to couple with a processor coupled to said row driver circuit and to said column driver circuit, and wherein said processor is configured to:
access layer slice information describing desired deposition of material onto said cathode; and
based on said layer slice information, set signals on said array of row traces and on said array of column traces to control said amount of current flowing through said conductive path of said each deposition element.
17. The system of claim 16 , wherein:
said processor is further coupled with at least one sensor; and
said processor is further configured to analyze data from said at least one sensor to determine when said desired deposition of material onto said cathode by said each deposition element is complete for a layer slice of said layer slice information.
18. The system of claim 11 , wherein a width of each conductive power trace of said lattice of conductive power traces is at least 10% of said grid pitch.
19. A matrix-controlled printhead for an electrochemical additive manufacturing system, comprising:
a deposition grid partitioned into grid regions along an x-axis direction and along a y-axis direction, said deposition grid comprising:
a grid x resolution defined as a number of grid regions along the x-axis direction;
a grid y resolution defined as a number of grid regions along the y-axis direction;
a grid x pitch defined as a length of a grid region of said grid regions along the x-axis direction;
a grid y pitch defined as a length of said grid region along the y-axis direction;
a grid pitch defined as a minimum of said grid x pitch and said grid y pitch; and
a grid region area defined as a geometric area of said grid region;
a grid control circuit comprising:
an array of row traces;
an array of column traces;
a row driver circuit coupled electrically to said row traces; and
a column driver circuit coupled electrically to said column traces;
a power distribution circuit;
an array of deposition elements aligned with said deposition grid, each deposition element of said array of deposition elements corresponding to a unique grid region of said grid regions, wherein said each deposition element comprises:
a deposition anode comprising
an conductive material;
an exposed surface comprising said conductive material wherein said exposed surface is configured to contact an electrolyte comprising an electrodeposition electrolyte; and
a conductive path through said deposition anode to said exposed surface;
a deposition control circuit coupled electrically to:
said deposition anode;
an associated row trace of said row traces;
an associated column trace of said column traces; and
said power distribution circuit;
one or more insulating layers between said deposition control circuit and said electrolyte;
wherein:
said deposition control circuit is configured to control an amount of conductivity and current between said power distribution circuit and said conductive path of said deposition anode;
when said exposed surface is placed in contact with said electrolyte, and when said current flows through said conductive path, said current causes an electrochemical deposition reaction on a cathode;
a length of said conductive path of said deposition anode of each deposition element of said array of deposition elements is at least 10% of said grid pitch;
said grid x resolution is at least 100 and said grid y resolution is at least 100;
said deposition anode of each deposition element of said array of deposition elements comprises one or more layers of said conductive material above said deposition control circuit of each deposition element of said array of deposition elements;
said conductive material of said deposition anode of each deposition element of said array of deposition elements comprises one or more of platinum group metals and their associated oxides, highly doped semiconducting materials, and carbon nanotubes;
power distribution circuit comprises a lattice of conductive power traces aligned with said deposition grid, wherein said conductive power traces are electrically coupled to one another at one or more points where said lattice of conductive power traces cross;
a width of each conductive power traces of said lattice of conductive power traces is at least 10% of said grid pitch; and
an area of said exposed surface of said deposition anode of each deposition element of said array of deposition elements is at least 15% of said grid region area.