Method for photo-forming small shaped metal containing articles from porous precursors

• US 5,512,162 A
• Filed: 08/13/1992
• Issued: 04/30/1996
• Est. Priority Date: 08/13/1992
• Status: Expired due to Fees

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Tsao, Che-Chih, Sachs, Emanuel
• Primary Examiner(s): Niebling, John
• Assistant Examiner(s): Leader, William T.
• Application Number:
  US07/929,604
• Time in Patent Office: 1,356 Days
• Field of Search: 205/91, 205/114, 205/183, 205/184, 205/187, 205/144, 205/150, 205/161, 205/170, 205/918, 205/123, 205/136, 427/212, 427/222, 427/214, 427/215, 427/216, 427/217, 427/243, 427/581, 427/595, 427/596, 427/597, 427/404, 427/304-306, 430/322, 430/325, 430/394, 430/396, 156/272.2, 156/272.8, 156/273.3, 156/273.9, 156/275.1, 118/620
• US Class Current: 205/91
• CPC Class Codes: B22F 12/44 characterised by the configuration of the radiation means
• CPC Class Codes: B22F 12/67 Blades
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 70/00 Materials specially adapted for additive manufacturing
• CPC Class Codes: C23C 18/06 Coating on selected surface areas, e.g. using masks
• CPC Class Codes: C23C 18/143 Radiation by light, e.g. photolysis or pyrolysis
• CPC Class Codes: C23C 18/161 from plating step, e.g. inkjet
• CPC Class Codes: C23C 18/1612 through irradiation means
• CPC Class Codes: C23C 18/1619 Apparatus for electroless plating
• CPC Class Codes: C23C 18/1651 Two or more layers only obtained by electroless plating
• CPC Class Codes: C25D 1/00 Electroforming
• CPC Class Codes: C25D 1/003 3D structures, e.g. superposed patterned layers
• CPC Class Codes: G03C 5/58 Processes for obtaining metallic images by vapour deposition or physical development images obtained by photomechanical means, e.g. by etching G03F
• CPC Class Codes: H05K 3/185 by making a catalytic pattern by photo-imaging
• CPC Class Codes: Y02P 10/25 Process efficiency

Abstract

The invention is a method for making a metal containing article, comprising the steps of: providing a layer of a porous ground in a selected area; exposing selected regions of the layer of porous ground to light, thereby metallizing the selected regions; repeating the foregoing steps a selected number of times to produce a selected number of layers; and selectively modifying the metallized regions of the layers. The initial metallization can be by electroless or semiconductor photo deposition plating. The subsequent modification of the metallized regions can be by electroless plating, electroplating or sintering. It is also possible, in some instances, to forego the second phase modification, the initial phase having provided the desired parameters. In a third preferred embodiment, the invention is a method using an initial metallization phase effected by exposure of a metal salt, such as a metal halide, to light, thereby inducing activation of the halide. A subsequent metallization step is conducted, as well as subsequent modification according to any of the methods mentioned above. A continuous embodiment of the invention is also disclosed, where a continuously deposited bed of powder particles is exposed to light and metallized. Subsequently, the metallized regions are further modified as above. An apparatus for the practice of the continuous methods is also proposed. ?

Claims

1. A method for making a metal-containing article, comprising the steps of:

a. providing a layer of a porous ground on a selected area of a base substantially immersed within a fluid that contains a metal source;

b. exposing selected regions of said layer of porous ground to light, thereby metallizing said selected regions;

c. repeating steps (a) and (b) a selected number of times to produce a selected number of layers; and

d. joining said metallized regions of at least two of said layers.

2. The method of claim 1, said porous ground comprising a powder of metal coated with an electrically non-conducting material.

3. The method of claim 1, further comprising the step of detaching from said metallized regions selected regions of said ground that have not been metallized.

4. The method of claim 1, further comprising the step of further transforming selected regions of said ground that have not been metallized.

5. The method of claim 4, said step of further transforming comprising the step of impregnating said unmetallized ground with a structural composition.

6. The method of claim 1, said metallizing step comprising the step of electroless plating said selected regions.

7. The method of claim 6, said step of joining said metallized regions comprising electroless plating.

8. The method of claim 6, said step of joining said metallized regions comprising electroplating.

9. The method of claim 6, said step of joining said metallized regions comprising sintering.

10. The method of claim 1, said metallizing step comprising the step of light induced semiconductor plating said selected regions.

11. The method of claim 10, said step of joining said metallized regions comprising electroless plating.

12. The method of claim 10, said step of joining said metallized regions comprising electroplating.

13. The method of claim 10, said step of joining said metallized regions comprising sintering.

14. A method for making a metal-containing article comprising the steps of:

a. providing a layer of a porous ground on a selected area of a base;

b. contacting said porous ground with an electroless plating solution;

c. exposing selected regions of said layer of porous ground to light, thereby metallizing said selected regions;

d. repeating steps (a) and (b) and (c) a selected number of times, each successive layer provided adjacent a layer that has already been formed, to produce a selected number of metallized layers, said metallization adding metal within said metallized regions of each individual layer and between said metallized regions of adjacent layers.

15. The method of claim 14, said electroless plating solution comprising a metal selected from the group consisting of:

copper, nickel, cobalt and palladium.

16. A method for making a metal-containing article, comprising the steps of:

a. providing a layer of a porous, metal salt-containing ground on a selected area of a base;

b. exposing selected regions of said layer of porous ground to light, thereby activating said selected regions;

c. repeating steps (a) and (b) a selected number of times to produce a selected number of layers;

d. metallizing said activated regions; and

e. joining said metallized regions of at least two of said layers.

17. The method of claim 16, said step of joining said metallized regions comprising the step of electroless plating additional metal within said metallized regions of individual layers and between said metallized regions of adjacent layers.

18. The method of claim 16, said step of joining said metallized regions comprising the step of electroplating additional metal within said metallized regions of individual layers and between said metallized regions of adjacent layers.

19. The method of claim 16, said step of joining said metallized regions comprising the step of sintering metal within said metallized regions of individual layers and between said metallized regions of adjacent layers.

20. The method of claim 16, said ground comprising a ceramic coated with a metal halide.

21. The method of claim 16, said ground comprising a polymeric sheet coated with a metal halide.

22. A method for making a metal-containing article, comprising the steps of:

a. providing porous ground on a selected area of a base substantially immersed within a fluid that contains a metal source;

b. while the providing of step (a) is continuing, exposing selected regions of said porous ground to light, thereby metallizing said selected regions to a selected degree and to a preselected depth; and

c. joining said metallized regions of porous ground that are adjacent to each other.

23. The method of claim 22, said metallizing comprising the step of electroless plating.

24. The method of claim 22, said metallizing comprising the step of semiconductor plating.

25. The method of claim 22, said step of joining said metallized regions comprising the step of electroless plating additional metal within said metallized selected volume of porous ground.

26. The method of claim 22, said step of joining said metallized regions comprising the step of electroplating additional metal within said metallized porous ground.

27. The method of claim 22, said step of joining said metallized regions comprising the step of sintering within said metallized of porous ground.

28. A method for making a metal-containing article, comprising the steps of:

a. providing porous ground on a selected area of a base;

b. contacting said porous ground with an electroless plating solution;

c. while the providing of step (a) is continuing, exposing selected regions of said porous ground to light, thereby metallizing said selected regions to a preselected degree and to a preselected depth.

29. A method for making a metal-containing article, comprising the steps of:

a. providing porous metal salt ground on a selected area of a base;

b. while the providing of step (a) is continuing, exposing selected regions of said porous ground to light, thereby activating said selected regions to a preselected degree and to a preselected depth;

c. metallizing the selectively activated regions and

d. joining said metallized regions of porous ground that are adjacent to each other.

30. The method of claim 29, said step of joining said metallized regions comprising the step of electroless plating additional metal within said metallized porous ground.

31. The method of claim 29, said step of joining said metallized regions comprising the step of electro plating additional metal within said metallized porous ground.

32. The method of claim 29, said step of joining said metallized regions comprising the step of sintering within said metallized porous ground.