Fabrication process for co-fabricating multilayer probe array and a space transformer
Embodiments of the invention provide fabrication processes for the co-fabrication of microprobe arrays along with one or more space transformers wherein the fabrication processes include the forming and adhering of a plurality of layers to previously formed layers and wherein at least a portion of the plurality of layers are formed from at least one structural material and at least one sacrificial material that is at least in part released from the plurality of layers after formation and wherein the space transformer includes a plurality of interconnect elements that connect one side to the array of probes that has a first spacing to another side that has a second spacing where the second spacing is greater than the first spacing. In some embodiments, the fabrication process includes a plurality of electrodeposition operations.
1. A fabrication process for co-fabricating a multi-layer probe array and a space transformer, comprising:
(a) forming and adhering a first layer of material to a substrate, wherein the first layer comprises a desired pattern of at least one material;
(b) repeating the forming and adhering operation of the steps of (a) a plurality of times to build up the array of probes and the space transformer from a plurality of adhered layers, and wherein at least a portion of the plurality of layers comprises at least one structural material and at least one sacrificial material; and
(c) after formation of the plurality of layers, subjecting the plurality of adhered layers to a release process that removes at least a portion of the at least one sacrificial material from the plurality of adhered layers,
wherein the space transformer comprise a plurality of interconnect elements that connect on one side to the array of probes that have a first spacing and connect to pads on another side that have a second spacing that is greater than the first spacing.
2. The process of claim 1 wherein the forming and adhering operation of the steps of (a) comprises an electrochemical deposition process.
3. The method of claim 1 wherein the at least one structural material comprises an electrodeposited metal and the at least one sacrificial material comprises an electrodeposited metal.
4. The method of claim 3 wherein during formation of each of the plurality of layers at least one planarization operation is used to planarize at least the one sacrificial material and the at least one structural material.