Methods of and apparatus for electrochemically fabricating structures via interlaced layers or via selective etching and filling of voids

• US 20040007470A1
• Filed: 05/07/2003
• Published: 01/15/2004
• Est. Priority Date: 05/07/2002
• Status: Active Grant

• Current Assignee: Microfabrica Incorporated (Technoprobe S.P.A.)
• Original Assignee: Memgen Corporation (Technoprobe S.P.A.)
• Inventors: Smalley, Dennis R.
• Granted Patent: US 7,252,861 B2
• Time in Patent Office: Days
• US Class Current: 205/118
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 50/00 Data acquisition or data processing for additive manufacturing
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B81B 2201/042 Micromirrors, not used as optical switches
• CPC Class Codes: B81C 1/00126 Static structures not provided for in groups B81C1/00031 - B81C1/00119
• CPC Class Codes: B81C 1/0038 Processes for creating layers of materials not provided for in groups B81C1/00357 - B81C1/00373
• CPC Class Codes: C23C 18/1605 by masking
• CPC Class Codes: C23C 18/1651 Two or more layers only obtained by electroless plating
• CPC Class Codes: C25D 1/003 3D structures, e.g. superposed patterned layers
• CPC Class Codes: C25D 5/02 Electroplating of selected surface areas
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: G06F 30/392 Floor-planning or layout, e.g. partitioning or placement
• CPC Class Codes: H01L 21/2885 using an external electrical current, i.e. electro-deposition
• CPC Class Codes: H01L 21/76885 By forming conductive members before deposition of protective insulating material, e.g. pillars, studs
• CPC Class Codes: H01P 1/202 Coaxial filters cascaded coaxial cavities H01P1/205
• CPC Class Codes: H01P 11/00 Apparatus or processes specially adapted for manufacturing waveguides or resonators, lines, or other devices of the waveguide type
• CPC Class Codes: H01P 11/005 Manufacturing coaxial lines
• CPC Class Codes: H01P 3/06 Coaxial lines
• CPC Class Codes: H01P 5/183 at least one of the guides being a coaxial line
• CPC Class Codes: H05K 3/4647 : by applying an insulating layer around previously made via studs

Abstract

Multi-layer structures are electrochemically fabricated by depositing a first material, selectively etching the first material (e.g. via a mask), depositing a second material to fill in the voids created by the etching, and then planarizing the depositions so as to bound the layer being created and thereafter adding additional layers to previously formed layers. The first and second depositions may be of the blanket or selective type. The repetition of the formation process for forming successive layers may be repeated with or without variations (e.g. variations in: patterns; numbers or existence of or parameters associated with depositions, etchings, and or planarization operations; the order of operations, or the materials deposited). Other embodiments form multi-layer structures using operations that interlace material deposited in association with some layers with material deposited in association with other layers.

Claims

1. A fabrication process for forming a multi-layer three-dimensional structure, comprising:

(a) forming and adhering a layer of material to a previously formed layer and/or to a substrate; and

(b) repeating the forming and adhering operation of (a) a plurality of times to build up a three-dimensional structure from a plurality of adhered layers;

wherein the formation of at least a plurality of layers, comprise;

(1) depositing a first material onto a substrate or previously formed layer;

(2) selectively etching the first material to a desired depth to create voids;

(3) depositing a second material at least into the voids created by the selective etching operation (2),

wherein at least one of the depositing operations is an electrodeposition operation.

2. The process of claim 1 wherein the depositing of the first material for a given layer comprises an electroplating of the first material via blanket deposition.

3. The process of claim 2 wherein the depositing of the second material for a given layer comprises an electroplating of the second material via blanket deposition.

4. The process of claim 3 wherein the selective etching of the first material for a given layer comprises an electrochemical etching operation and utilization of a contact mask.

5. The process of claim 3 wherein the selective etching of the first material for a given layer comprises chemical etching and utilization of a contact mask.

6. The process of claim 1 additionally comprising a planarization of the deposited first material during the formation of a given layer prior to the selective etching of the first material for the given layer.

7. The process of claim 1 additionally comprising a planarization of the deposited second material during the formation of a given layer.

8. The process of claim 1 additionally comprising, after the deposition of the second material during the formation of a given layer:

(4) selectively etching either the first material and/or the second material to a desired depth to create voids within the given layer; and

(5) depositing a third material into the voids created by the selective etching operation of element (4).

9. The process of claim 1 wherein the depositing of the first material comprises a selective electroplating of the first material in a desired pattern

10. The process of claim 8 wherein the selective electroplating of the first material for a given layer utilizes a contact mask of a desired configuration.

11. The process of claim 1 wherein the depositing of the second material for a given layer comprises a selective electroplating of the second material in a desired pattern.

12. The process of claim 11 wherein the selective electroplating of the second material for a given layer utilizes a contact mask of a desired configuration.

13. The process of claim 1 wherein the desired depth, when forming a given layer, is substantially equal to or greater than the difference in height between successive layer levels.

14. The process of claim 1 wherein selective etching is performed using one or more of:

(1) a contact mask, (2) a proximity mask, (3) an adhered mask, and/or (4) selected ablation via controlled relative scanning of a laser beam the first material.

15. A fabrication process for forming a multi-layer three-dimensional structure, comprising:

(a) forming and adhering a layer of material to a previously formed layer and/or to a substrate; and

(b) repeating the forming and adhering operation of (a) a plurality of times to build up a three-dimensional structure from a plurality of adhered layers;

wherein the formation of at least a given layer and a subsequent layer adjacent to the given layer comprises;

(1) in association with a layer level for the given layer, depositing a first material onto a substrate or previously formed layer;

(2) planarizing the surface of the deposited first material to a layer level that bounds the given layer;

(3) selectively etching the first material to a desired depth to create voids in the given layer;

(4) depositing a second material to reach a layer level at least as great as a level that bounds the subsequent layer;

(5) planarizing the surface of the deposited second material to the layer level that bounds the subsequent layer; and

(6) selectively etching the second material to a desired depth to create voids in the subsequent layer.

16. The process of claim 15 wherein at least one of the depositing of the first material or the depositing of the second material for at least one layer comprises an electrodeposition operation.

17. The process of claim 16 wherein formation of a plurality of additional pairs of layers comprise repeating operations (1)-(6) during the formation of each pair of layers.

18. The process of claim 17 wherein the pairs of layers include a first and a second layer, the second and a third layer, the third and a fourth layer.

19. The process of claim 15 wherein the second material is deposited into the voids created by the selective etching operation (3) to form a portion of the given layer as well as a portion of the subsequent layer.

20. The process of claim 15 additionally comprising:

(7) depositing the first material into voids created by the etching operation (6) to form a portion of the subsequent layer.

21. The process of claim 20 wherein an immediately succeeding layer is located on the subsequent layer and is intended to comprise the first material and wherein the depositing of the first material of operation (7) is of a sufficient extent to occupy the immediately succeeding layer and to reach at least a level that bounds the immediate succeeding layer and after the deposition of operation (7) planarizing the resulting deposition to the level that bounds the immediately succeeding layer.

22. The process of claim 20 wherein after the depositing of the first material of operation (7), planarizing the deposition of operation (7) at the level that bounds the subsequent layer.

23. A fabrication process for forming a multi-layer three-dimensional structure, comprising:

(a) forming and adhering a given layer of material to a previously formed layer and/or to a substrate;

(b) repeating the forming and adhering operation of (a) a plurality of times to build up a three-dimensional structure from a plurality of adhered layers;

wherein the formation of at least a plurality of layers, comprises beginning a deposition operation to form a portion of a subsequent layer prior to completing formation of a previous layer.

24. The process of claim 23 wherein the formation of the given layer comprises electrodeposition of a material.

25. The process of claim 23 wherein the formation of the previous layer, comprises:

(c) depositing one or more structural materials;

(d) depositing one or more sacrificial materials;

(e) planarizing at least one deposited material such that the resulting position of the deposited material bounds a level of the previous layer; and

(e) etching into at least one of the structural materials at one or more positions and to one or more depths to form at least one or more voids in the previous layer such that the one or more voids do not expose sacrificial material.

26. The process of claim 25 wherein the formation of the previous layer comprises electrodeposition of a material.

27. The process of claim 25 wherein the formation of the previous layer and subsequent layer comprises:

(g) depositing at least one of the structural materials to form part of the subsequent layer while simultaneous depositing material into the one or more voids formed in the previous layer.

28. The process of claim 23 wherein the formation of the previous layer, comprises:

(c) depositing one or more structural materials;

(d) depositing one or more sacrificial materials;

(e) planarizing at least one deposited material such that the resulting position of the deposited material bounds a level of the previous layer; and

(f) etching into at least one of the structural materials at one or more positions and to one or more depths to form one or more voids such that at least one or more of the one or more voids expose sacrificial material.

29. The process of claim 28 wherein the formation of the previous layer comprises electrodeposition of a material.

30. The process of claim 25 wherein the formation of the previous layer and subsequent layer comprises:

(g) depositing at least one of the structural materials to form part of the subsequent layer while simultaneous depositing material into the one or more voids formed in the previous layer.

31. The process of claim 23 wherein formation of at least a plurality of layers, comprises beginning a deposition operation to form a portion of a successive layer prior to completing formation of an earlier layer that is separated from the successive layer by at least one intermediate layer.

32. The process of claim 31 wherein an etching operation associated with either the successive layer or the intermediate layer removes material from the intermediate layer and from the previous layer to form at least one void, wherein the at least one void is filled in with at least one structural material during a deposition operation performed in association with the successive layer.

33. A fabrication process for forming a multi-layer three-dimensional structure, comprising:

(a) forming and adhering a material for a given layer to a previously formed layer and/or to a substrate; and

(b) repeating the forming and adhering operation of (a) a plurality of times to build up a three-dimensional structure from a plurality of adhered layers;

wherein for a plurality of layers, a deposition of material in association with a given layer results in deposition of material into voids in a previous layer that was only partially completed.

34. The process of claim 33 wherein the formation of the given layer comprises electrodeposition of a material.

35. The process of claim 33 wherein the previous layer did not receive deposition of an appropriate material at each location until formation of the given layer is initiated.

36. The process of claim 35 wherein a material different from the appropriate material is made to temporarily fill in a void location in the previous layer, the temporary fill material is thereafter removed to create a void, and the appropriate material is made to fill the void during a process associated with the formation of the given layer.

37. The process of claim 33 wherein during deposition associated with the previous layer, the previous layer did receive deposition of appropriate material at each location but wherein an etching operation was performed that removed a portion of the material from the previous layer after it was nominally completed so as to allow material deposited in association with the given layer to fill at least one void created by the removal of material such that the formation of the previous layer was not complete until beginning formation of the given layer.

38. The process of claim 37 wherein the at least one void formed in the previous layer was not merely an accidental result or the result of a lack of control of deposition or etching but instead was a result of an intention to penetrate the bounding level of the previous layer whereby interlacing of material between previous and given layers results.

39. A fabrication process for forming a multi-layer three-dimensional structure, comprising:

(a) forming and adhering a layer of material to a previously formed layer and/or to a substrate; and

(b) repeating the forming and adhering operation of (a) a plurality of times to build up a three-dimensional structure from a plurality of adhered layers;

wherein for a plurality of layers, interlacing of material deposited in association with adjacent layers occurs whereby an inter-connection of material between at least some pairs of layers is enhanced.

40. The process of claim 39 wherein the formation of a plurality of layers comprises electrodeposition of a material.

41. The process of claim 39 wherein the inter-connection of material occurs from a given layer through an intermediate layer to a previous layer.

42. The process of claim 41 wherein the inter-connection of material occurs in a staggered manner through a plurality of layers such that interconnection of layers occurs via a plurality of interlacing elements that each connect at least three layers and such that an inter-connected network extending a greater distance than the height of any single interlacing element occurs.

43. The process of claim 42 wherein the staggered manner result in a given layer comprising at least two of:

(c) at least one interlacing element that extends from the given layer to a previous layer that is separated from the given layer by at least one intermediate layer,

(d) an interlacing element that originates on a subsequent layer, extends through the given layer and ends on a previous layer; and

/or

(e) an interlacing element that originates on a subsequent layer that is separated from the given layer by at least one intermediate layer and that ends on the given layer.

44. The process of claim 39 wherein some interlacing elements have different height.

45. The process of claim 44 wherein the height of at least some interlacing elements is at least in part dictated by the location of the interlacing elements relative to outward facing-surfaces of the structure, or of outward facing surfaces associated with a single structural material or a particular group of structural materials, or the interference between the interlacing elements and other interlacing elements.

46. The process of claim 39 wherein at least some voids are formed with undercuts.

47. The process of claim 46 wherein the voids having undercuts are formed using a conformable contact mask.

48. The process of claim 39 wherein selective patterning for forming voids or for selectively depositing a selected material utilizes one or more of:

(1) a contact mask, (2) a proximity mask, and/or (3) an adhered mask.