Wafer scale test interface unit and contactors
Devices and methods for multilayer packages, antenna array feeds, test interface units, connectors, contactors, and large format substrates. The device comprising a 3D coaxial distribution network structure including a plurality of coaxial transmission lines separated by a first pitch at the input and a second, wider pitch at the output thereof.
1. A wafer level test interface device, comprising a device interface layer having a plurality of coaxial transmission lines extending therethrough from a first surface of the layer to an opposing second surface of the layer, the transmission lines having respective ends spaced relative to one another at the first surface separated by a first distance and having respective ends spaced relative to one another at the second surface separated by a second distance which is larger than the first distance, wherein the coaxial transmission lines comprise a center conductor suspended in air and surrounded by conductive shielding.
2. The wafer level test interface device of claim 1 , comprising a contactor probe assembly having a plurality of conductive probes extending therethrough from a first surface of the probe assembly to an opposing second surface of the probe assembly, each of the conductive probes disposed in electrical communication with a respective transmission line of the device interface layer.
3. The wafer level test interface device of claim 2 , wherein the conductive probes have end portions that extend outward from the first surface of the probe assembly, and wherein the end portions are resiliently movable relative to the first surface of the probe assembly.
4. The wafer level test interface device of claim 3 , wherein the conductive probes comprise one or more of a spring, MEMS, a cantilever, a flexure, a single-sided pogo pin, or a double-sided pogo pin.
5. The wafer level test interface device of claim 3 , comprising a shield wall disposed between a selected pair of the end portions to minimize crosstalk between the selected pair.
6. The wafer level test interface device of claim 1 , wherein the coaxial transmission lines include first end portions that extend outward from the first surface of the layer, and wherein the end portions are resiliently movable relative to the first surface of the layer.
7. The wafer level test interface device of claim 6 , wherein the coaxial transmission lines include a spring configured to allow the end portions to resiliently move relative to the first surface of the layer.
8. The wafer level test interface device of claim 7 , wherein the spring comprises a “C”-shape.
9. The wafer level test interface device of claim 7 , wherein the spring comprises alternating “C”-shaped sections where each “C”-shaped section comprises a flexure.
10. The wafer level test interface device of claim 1 , wherein the coaxial transmission lines each comprise a center conductor having a spring that allows the center conductor to resiliently move within the device interface layer.
11. The wafer level test interface device of claim 1 , comprising at least one of a passive electrical component and/or active electrical component disposed within the device interface layer between a center conductor and an outer conductor of the coaxial transmission lines.
12. The wafer level test interface device of claim 1 , comprising a N×M switch disposed in electrical connection with selected ones of the coaxial transmission lines.
13. A method of forming a wafer level test interface device by a sequential build process, comprising:
sequentially depositing a plurality of layers, wherein the layers comprise one or more layers of a conductive material and one or more layers of a sacrificial material, the plurality of layers collectively providing a device interface structure having a plurality of coaxial transmission lines extending therethrough from a first surface of the layer to an opposing second surface of the layer, the transmission lines comprising a center conductor suspended in an airspace and surrounded by conductive shielding and the transmission lines having respective ends spaced relative to one another at the first surface separated by a first distance and having respective ends spaced relative to one another at the second surface separated by a second distance which is larger than the first distance; and
removing the sacrificial material to provide the airspace between the center conductor and conductive shielding.
14. The wafer level test interface device of claim 1 , wherein the coaxial transmission lines include, between first and second ends, an intermediate transmission line portion having a longitudinal axis associated therewith, and wherein a longitudinal axis of the first end is not parallel to the longitudinal axis of the intermediate transmission line portion.
15. The wafer level test interface device of claim 14 , wherein longitudinal axis of the first end is perpendicular to the longitudinal axis of the intermediate transmission line portion.
16. The method of claim 13 , wherein the coaxial transmission lines each comprise a center conductor having a spring that allows the center conductor to resiliently move within the device interface structure.
17. The method of claim 13 , wherein the coaxial transmission lines include first end portions that extend outward from the first surface of the layer, and wherein the end portions are resiliently movable relative to the first surface of the layer.
18. The method of claim 17 , wherein the coaxial transmission lines include a spring configured to allow the end portions to resiliently move relative to the first surface of the layer.
19. The method of claim 18 , wherein the spring comprises a “C”-shape.
20. The method of claim 18 , wherein the spring comprises alternating “C”-shaped sections where each “C”-shaped section comprises a flexure.
21. The method of claim 13 , comprising providing at least one of a passive electrical component and/or active electrical component within the device interface structure between a selected pair of the plurality of coaxial transmission lines.