Package interconnects
View Patent ↗A method for forming a device is disclosed. A support substrate having first and second major surfaces is provided. An interconnect is formed through the first and second major surfaces in the support substrate. The interconnect has first and second portions. The first portion extends from one of the first or second major surfaces and the second portion extends from the other of the first and second major surfaces. The interconnect includes a partial via plug having a conductive material in a first portion of the interconnect. The via plug has a bottom at about an interface of the first and second portions. The second portion of the interconnect is heavily doped with dopants of a first polarity type.
1. A method for forming a device comprising:
providing a support substrate having first and second major surfaces;
forming an interconnect through the first and second major surfaces in the support substrate, the interconnect having first and second portions, the first portion extends from one of the first or second major surfaces and the second portion extends from other of the first and second major surfaces, wherein forming the interconnect includes
forming a partial via plug comprising a conductive material in the first portion of the interconnect, the via plug having a bottom at about an interface of the first and second portions, and
providing the second portion of the interconnect with a heavily doped second portion with dopants of a first polarity type; and
forming an isolation trench surrounding the interconnect to isolate the interconnect from portions of the support substrate.
2. The method of claim 1 wherein the conductive material comprises polysilicon.
3. The method of claim 2 wherein the polysilicon is doped with dopants of the first polarity type.
4. The method of claim 1 wherein the first polarity type is n type.
5. The method of claim 1 comprises filling the isolation trench with a dielectric material, wherein the dielectric material fills the isolation trench and over the first major surface of the support substrate.
6. The method of claim 5 comprises removing excess dielectric material over the support substrate to form a planar first surface dielectric layer over the first major surface of the support substrate.
7. The method of claim 1 wherein the partial via plug is formed by deep reactive ion etch.
8. The method of claim 1 wherein forming a partial via plug comprising
patterning the support substrate to form a partial via;
depositing a conductive material on the support substrate and filling the partial via; and
removing excessive conductive material over the support substrate leaving a via pad coupled to the partial via plug.
9. The method of claim 8 comprises forming a dielectric layer over the first surface dielectric layer.
10. The method of claim 9 comprises forming a contact opening in the dielectric layer to expose the via pad.
11. The method of claim 10 comprises forming a conductive trace on the dielectric layer and coupled to the via pad.
12. The method of claim 1 comprises attaching a semiconductor device over the support substrate.
13. A method for forming a semiconductor package comprising:
providing a support substrate having first and second major surfaces;
forming an interconnect through the first and second major surfaces in the support substrate, the interconnect having first and second portions, the first portion extends from one of the first or second major surfaces and the second portion extends from other of the first and second major surfaces, wherein forming the interconnect includes
forming a partial via plug comprising a conductive material in the first portion of the interconnect, the via plug having a bottom at about an interface of the first and second portions, wherein the conductive material comprises polysilicon which is doped with dopants of a first polarity type, and
providing the second portion of the interconnect with a heavily doped second portion with dopants of the first polarity type; and
providing a semiconductor device over the support substrate.
14. A device comprising:
a support substrate having first and second major surfaces;
an interconnect through the first and second major surfaces in the support substrate, the interconnect having first and second portions, the first portion extends from one of the first or second major surfaces and the second portion extends from other of the first and second major surfaces, wherein the interconnect includes
a partial via plug comprising a conductive material in the first portion of the interconnect, the via plug having a bottom at about an interface of the first and second portions, and
the second portion of the interconnect is heavily doped with dopants of a first polarity type; and
an isolation trench surrounding the interconnect to isolate the interconnect from portions of the support substrate.
15. The device of claim 14 wherein the conductive material comprises polysilicon.
16. The device of claim 15 wherein the polysilicon is doped with dopants of the first polarity type.
17. The device of claim 14 wherein the first polarity type is n type.
18. The device of claim 14 wherein the isolation trench includes a dielectric material.
19. The device of claim 14 wherein the partial via plug comprises a surface end extending from the first major surface of the substrate.
20. The method of claim 1 wherein the partial via plug comprises a surface end extending from the first major surface of the substrate.