Method for providing hermetic electrical feedthrough

1. A method of fabricating a hermetic electrical feedthrough, the method comprising:

providing a ceramic sheet, and having an upper surface and a lower surface, wherein said sheet includes silicon dioxide;

forming at least one via hole in said sheet extending from said upper surface to said lower surface;

inserting a conductive thickfilm paste, including platinum, into said via hole;

laminating said sheet with said conductive thick film paste in said via hole between an upper ceramic sheet, and a lower ceramic sheet, to form a laminated substrate wherein said via hole is encased in ceramic;

selecting an oxygen controlled environment, between 10 −38 and 10 −3 atmospheres of oxygen partial pressure, by introduction of other gasses selected from the group consisting of C0 2 /CO, C0 2 /NH 3 , C0 2 /H 2 , H 2 0/H 2 , H 2 0/NH 3 , H 2 0/CO, Nitrogen, or Argon, under vacuum to balance platinum oxidation and silicon dioxide decomposition of said laminated substrate;

firing said laminated substrate in said oxygen controlled environment to a temperature to sinter said laminated substrate to form a single sintered structure and cause said conductive thick film paste in said via hole to form a metallized via, including platinum in contact with ceramic, and cause said laminated substrate to form a fired laminated substrate and a hermetic seal around said metallized via; and

removing said upper sheet material and said lower sheet material by lapping or grinding, to expose an upper and a lower surface of said metallized via.

2. The method according to claim 1 , wherein said oxygen controlled environment is a vacuum.

3. The method according to claim 1 , wherein said sheet is formed of material comprised of at least 90% aluminum oxide.

4. The method according to claim 1 , wherein said fired laminated substrate after said firing and material removal steps is less than or equal to 40 mils thick.

5. The method according to claim 1 , wherein said fired laminated substrate after said firing and material removal steps is less than 15 mils thick.

6. The method according to claim 1 , wherein forming at least one via hole in said sheet comprises punching said via hole using a punch tool, etching said via hole using a solvent etching, using laser ablation or drilling said via hole.

7. The method according to claim 1 , wherein inserting a conductive material into said via hole comprises:

disposing said sheet with said via hole between a stencil layer and a vacuum base, wherein said stencil layer includes at least one through hole that is aligned above said via hole;

rolling said conductive material across said stencil layer; and

pulling said conductive material into said via hole through said hole in said stencil layer with a vacuum created by said vacuum base.

8. The method according to claim 1 , further comprising laminating said sheet with paste filled via holes between said upper sheet and said lower sheet to form said laminated substrate;

placing said sheet with paste filled via holes together with said upper ceramic sheet and said lower ceramic sheet in a heatpress; and

applying heat and pressure by said heatpress until said laminated substrate is formed.

9. The method according to claim 1 , wherein said ceramic material comprises aluminum oxide, zirconium oxide or a mixture thereof.

10. The method according to claim 1 , wherein said fired laminated substrate has a thickness of less than 20 mils after removing said upper ceramic sheet and said lower ceramic sheet material.

11. The method according to claim 1 , wherein said fired laminated substrate has a thickness of 15-20 mils after removing said upper ceramic sheet and said lower ceramic sheet material.

12. A method of fabricating a hermetic electrical feedthrough, the method comprising:

providing a ceramic sheet and having an upper surface and a lower surface, wherein said sheet includes silicon dioxide;

forming at least one via hole in said sheet extending from said upper surface to said lower surface;

inserting a conductive thickfilm paste including platinum into said via hole forming a substrate;

selecting an oxygen controlled environment between 10 −38 and 10 −3 atmospheres of oxygen, the partial pressure of oxygen controlled by introduction of other gasses, selected from the group consisting of CO 2 /CO, CO 2 /NH 3 , CO 2 /H 2 , H 2 O/H 2 , H 2 O/NH 3 , H 2 O/CO, Nitrogen, or Argon, under vacuum to balance platinum oxidation and silicon dioxide decomposition of said substrate; and

firing said substrate to a temperature to sinter said sheet and cause said conductive thick film paste in said via hole to form a metallized via, including ceramic and platinum, and cause said sheet to form a hermetic seal around said metallized via.

13. The method according to claim 12 , wherein said oxygen controlled environment is a vacuum.

14. The method according to claim 12 , wherein said sheet is formed of material comprised of at least 90% aluminum oxide.

15. The method according to claim 12 , wherein said sheet after said firing is less than 15 mils thick.

16. The method according to claim 12 , wherein inserting a conductive material into said via hole comprises:

disposing said sheet with the via hole between a stencil layer and a vacuum base, wherein said stencil layer includes at least one through hole that is aligned above said via hole;

rolling said conductive material across said stencil layer; and

pulling said conductive material into said via hole through said hole in said stencil layer with a vacuum created by said vacuum base.