Methods of forming vias in multilayer substrates

1. A method of forming an electrical connection, the method comprising the steps of:

forming a via in a first circuit layer of a substrate;

placing a first electrically conductive substance in said via so that the first electrically conductive substance is carried by the first circuit layer, the first electrically conductive substance being electrically connected with an element of the first circuit layer;

placing a second electrically conductive substance on a second circuit layer of the substrate so that the second electrical substance is electrically connected with an element of the second circuit layer, the second electrically conductive substance being positioned proximate said first electrically conductive substance; and

applying heat such that a physical relation between said first and second electrically conductive substances is altered, the first and second circuit layers being electrically connected to each other after the heat application, wherein said first electrically conductive substance comprises a pin fixed within said via and said second electrically conductive substance comprises a preformed washer having a hole, wherein said hole receives said pin and said washer melts to electrically connect the first and second circuit layers during said heating step.

2. The method of claim 1 , wherein said heating step melts said second electrically conductive substance such that a surface tension of said melted substance allows said second electrically conductive substance to bead up and contact said first electrically conductive substance.

3. The method of claim 1 , wherein said heating step comprises using a laser to generate heat.

4. A method of forming an electrical connection, the method comprising the steps of:

forming a via in a first circuit layer of a substrate;

placing a first electrically conductive substance in said via so that the first electrically conductive substance is carried by the first circuit layer, the first electrically conductive substance being electrically connected with an element of the first circuit layer;

placing a second electrically conductive substance on a second circuit layer of the substrate so that the second electrical substance is electrically connected with an element of the second circuit layer, the second electrically conductive substance being positioned proximate said first electrically conductive substance;

applying heat such that a physical relation between said first and second electrically conductive substances is altered, the first and second circuit layers being electrically connected to each other after the heat application; and

a step for applying an amorphous thin film to one of a first contact side of the first layer and a second contact side of the interposer structure and applying a voltage to said layers to anodically bond said layers together at a temperature below 300 degrees Celsius, wherein said anodic bonding heats said area.

5. The method of claim 4 , wherein said amorphous thin film comprises one of silicon and silicon suboxide.

6. The method of claim 4 , wherein said voltage is approximately 700 volts.

7. The method of claim 1 , wherein said first and second electrically conductive substances are in contact with each other prior to said heating step.

8. The method of claim 1 , wherein said heating step comprises using an electrically heated block proximate to the area to be heated.

9. In a substrate comprising at least a first and a second layer, each of the first and second layers having a periphery and having at least one electrical trace on a surface of the layers, the first and second layers capable of being connected at a plurality of points around the periphery such that the surfaces are not in physical contact with each other, a method of forming an electrical connection between the first layer and the second layer, the method comprising the steps of:

forming a hole in the first layer;

placing a first electrically conductive substance in said hole;

placing a second electrically conductive substance on the second layer adjacent said hole;

heating an area around said hole and said second electrically conductive substance until said first and second electrically conductive substances at least partially melt to form the electrical connection; and

applying a voltage to said layers to anodically bond said layers together at the plurality of points, said voltage generating sufficient heat to accomplish said heating step.

10. The method of claim 9 , wherein said heating step melts said second electrically conductive substance such that a surface tension of said melted substance allows said substance to bead up and contact said first electrically conductive substance.

11. The method of claim 9 , wherein said heating step comprises using a laser to heat said area.

12. The method of claim 9 , wherein said heating step comprises using an electrically heated block proximate to the area to be heated.

13. The method of claim 9 , wherein said heating step comprises using Joule heating of a fusible link itself to heat said area.

14. The method of claim 9 , wherein said voltage is approximately 700 volts.

15. The method of claim 9 , wherein said first and second electrically conductive substances are in contact with each other prior to said heating step.

16. The method of claim 15 , wherein said first electrically conductive substance comprises a pin fixed within said hole.

17. The method of claim 16 , wherein said second electrically conductive substance comprises a preformed washer having a second hole, wherein said hole receives said pin and said washer melts to form the electrical connection during said heating step.

18. The method of claim 1 , wherein the first and second electrically conductive substances are not in contact with each other prior to the application of heat.

19. A method of forming an electrical connection, the method comprising the steps of:

forming a via in a first circuit layer of a substrate;

placing a first electrically conductive substance in said via so that the first electrically conductive substance is carried by the first circuit layer, the first electrically conductive substance being electrically connected with an element of the first circuit layer;

placing a second electrically conductive substance on a second circuit layer of the substrate so that the second electrical substance is electrically connected with an element of the second circuit layer, the second electrically conductive substance being positioned proximate said first electrically conductive substance; and

applying heat such that a physical relation between said first and second electrically conductive substances is altered, the first and second circuit layers being electrically connected to each other after the heat application, wherein:

a silicon bond line of one of the circuit layers is displaced from the other circuit layer prior to the application of heat; and

the silicon bond line is in contact with both the first and second circuit layers after the application of heat.

20. The method of claim 1 , wherein the electrical connection between the first and second circuit layers is located within an opening defined by an interposer layer that is positioned between the first and second circuit layers.

21. The method of claim 20 , further comprising:

applying an amorphous thin film to one of a first contact side of the first circuit layer and a second contact side of the interposer structure; and

applying a voltage to said first circuit layer and said interposer structure to anodically bond said first circuit layer and said interposer structure together.

22. The method of claim 1 , wherein a desired flow characteristic of the second electrically conductive substance is achieved by one of:

texturing a surface of the second electrically conductive substance; or

selecting a material composition of the second electrically conductive substance that corresponds with the desired flow characteristic.

23. The method of claim 1 , wherein said first electrically conductive substance comprises:

filler material disposed within said via; and

a pin fixed to said filler material, said pin and said filler material being carried by said first circuit layer.

24. The method of claim 1 , further comprising modifying a surface of the second electrically conductive substance by performing one of the following:

alloying a portion of the second electrically conductive substance;

metaliding a portion of the second electrically conductive substance; or

depositing a substance on the second electrically conductive substance.