Electrical assembly substrates for downhole use

1. An apparatus for performing well logging in a borehole intersecting an earth formation, the apparatus comprising:

a carrier conveyable in the borehole;

a tool disposed on the carrier comprising:

a substrate including a first attachment interface electrically connected to a second attachment interface by a substrate connection element, wherein the first attachment interface comprises a first attachment interface material and the second attachment interface comprises a second attachment interface material different than the first attachment interface material;

at least two circuit elements selected from circuit elements comprising: i) a terminal of a Gold (Au) terminal material electrically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by a AuSn solder join; ii) a terminal of a Silver (Ag) terminal material electrically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by a high melting point (HMP) Sn/Ag based solder join; iii) a terminal of a Tin (Sn) terminal material electrically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by a HMP Sn/Ag based solder join; iv) a terminal of a Silver (Ag) terminal material electrically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by a sintered Ag join.

2. The apparatus of claim 1 wherein at least one of the first attachment interface and the second attachment interface comprises an electrically conductive contact surface.

3. The apparatus of claim 1 wherein, for at least one circuit element of the at least two circuit elements, the circuit element terminal corresponding to the at least one circuit element is monometallic with the attachment interface corresponding to the at least one circuit element.

4. The apparatus of claim 3 wherein, for at least one circuit element of the at least two circuit elements, the join corresponding to the at least one circuit element is an electrically conductive join that is monometallic with the attachment interface corresponding to the at least one circuit element and the circuit element terminal corresponding to the at least one circuit element.

5. The apparatus of claim 1 wherein the substrate connection element comprises an additional conductor material different than the first attachment interface material and the second attachment interface material.

6. The apparatus of claim 5 wherein the additional conductor material is at least one of: i) multi-metallic; and ii) composite.

7. The apparatus of claim 1 wherein the substrate comprises a sequential physical vapor deposition material having deposition layers comprising at least one adhesion layer, at least one barrier layer, and at least one conductor layer.

8. The apparatus of claim 1 wherein the substrate comprises a first Tungsten-Titanium layer, a second Tungsten-Titanium layer, a Palladium layer, and a Gold layer between the Palladium layer and at least one of: i) the first Tungsten-Titanium layer, and ii) a second Tungsten-Titanium layer.

9. The apparatus of claim 1 wherein the substrate comprises a first Tungsten-Titanium layer, a second Tungsten-Titanium layer, a Titanium layer, and an Aluminum layer between the Titanium layer and at least one of: i) the first Tungsten-Titanium layer, and ii) a second Tungsten-Titanium layer.

10. The apparatus of claim 1 wherein the substrate comprises deposited layers including a first Titanium layer followed by a first Tungsten-Titanium barrier layer followed by a Palladium layer followed by a Gold layer followed by a second Tungsten-Titanium barrier layer followed by a second Titanium layer followed by an Aluminum layer followed by a third Tungsten-Titanium barrier layer followed by a third Titanium layer followed by a Nickel layer followed by a Silver layer.

11. An apparatus for performing well logging in a borehole intersecting an earth formation, the apparatus comprising:

a carrier conveyable in the borehole;

a tool disposed on the carrier comprising:

a substrate including a first attachment interface electrically connected to a second attachment interface by a substrate connection element, wherein the first attachment interface comprises a first attachment interface material and the second attachment interface comprises a second attachment interface material different than the first attachment interface material;

at least two circuit elements selected from circuit elements comprising: i) a Gold (Au) terminal material electrically monometallically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by Au wire; ii) an Aluminum (Al) terminal material electrically monometallically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by Al wire; iii) a Silver (Ag) terminal material electrically monometallically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by Ag wire.

12. The apparatus of claim 11 wherein at least one of the first attachment interface and the second attachment interface comprises an electrically conductive contact surface.

13. The apparatus of claim 11 wherein the substrate connection element comprises an additional conductor material different than the first attachment interface material and the second attachment interface material.

14. The apparatus of claim 13 wherein the additional conductor material is at least one of: i) multi-metallic; and ii) composite.

15. The apparatus of claim 11 wherein the substrate comprises a sequential physical vapor deposition material having deposition layers comprising at least one adhesion layer, at least one barrier layer, and at least one conductor layer.

16. The apparatus of claim 11 wherein the substrate comprises a first Tungsten-Titanium layer, a second Tungsten-Titanium layer, a Palladium layer, and a Gold layer between the Palladium layer and at least one of: i) the first Tungsten-Titanium layer, and ii) a second Tungsten-Titanium layer.

17. The apparatus of claim 11 wherein the substrate comprises a first Tungsten-Titanium layer, a second Tungsten-Titanium layer, a Titanium layer, and an Aluminum layer between the Titanium layer and at least one of: i) the first Tungsten-Titanium layer, and ii) a second Tungsten-Titanium layer.

18. A method of performing well logging in a borehole intersecting an earth formation, the method comprising:

conveying a carrier in the borehole, the carrier having disposed thereon a tool comprising:

a substrate including a first attachment interface electrically connected to a second attachment interface by a substrate connection element, wherein the first attachment interface comprises a first attachment interface material and the second attachment interface comprises a second attachment interface material different than the first attachment interface material;

at least two circuit elements selected from circuit elements comprising: i) a terminal of a Gold (Au) terminal material electrically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by a AuSn solder join; ii) a terminal of a Silver (Ag) terminal material electrically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by a high melting point (HMP) Sn/Ag based solder join; iii) a terminal of a Tin (Sn) terminal material electrically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by a HMP Sn/Ag based solder join; iv) a terminal of a Silver (Ag) terminal material electrically attached to at least one of the first attachment interface material of the substrate and the second attachment interface material of the substrate by a sintered Ag join; and

performing well logging, including sending signals over the at least two circuit elements.