SMALL VIAS IN A POLYMER LAYER DISPOSED ON A SUBSTRATE

1 . A method of processing a substrate having a conductive layer, comprising:

(a) depositing a polymer layer atop a substrate to cover an exposed conductive layer on the substrate;

(b) curing the polymer layer;

(c) forming a patterned masking layer directly atop the cured polymer layer;

(d) etching an exposed portion of the cured polymer layer through the patterned masking layer to form a via through the cured polymer layer to a top surface of the conductive layer; and

(e) removing the patterned masking layer.

2 . The method of claim 1 , wherein the polymer layer is thicker than the patterned masking layer.

3 . The method of claim 1 , wherein the polymer layer has a thickness of about 3 microns to about 7 microns.

4 . The method of claim 1 , wherein the patterned masking layer has a thickness of about 3 to about 10 microns.

5 . The method of claim 1 , wherein the patterned masking layer has a resolution that is less than the resolution of the polymer layer.

6 . The method of claim 1 , wherein the polymer layer includes one or more polyimide (PI) compounds.

7 . The method of claim 1 , wherein the patterned masking layer is a photoresist.

8 . The method of claim 1 , wherein the exposed portion of the polymer layer is etched with a plasma-based dry etching process.

9 . The method of claim 1 , wherein the via has a width of about 1 micron to about 5 microns.

10 . The method of claim 1 , wherein the via has a sidewall profile angle of about 80 degrees and about 90 degrees.

11 . A method of processing a substrate having a conductive layer, comprising:

(a) depositing a polymer layer atop a substrate;

(b) curing the polymer layer;

(c) depositing a hard mask layer atop the cured polymer layer;

(d) forming a patterned masking layer atop the hard mask layer;

(e) etching exposed portions of the hard mask layer through the patterned masking layer to a top surface of the cured polymer layer;

(f) etching exposed portions of the cured polymer layer through the patterned masking layer and the hard mask layer to a top surface of the conductive layer to form a via through the cured polymer layer; and

(g) removing the patterned masking layer.

12 . The method of claim 11 , wherein the hard mask layer is an inorganic material.

13 - 20 . (canceled)

21 . A method of processing a substrate having a conductive layer, comprising:

(a) depositing a polymer layer atop a substrate to cover an exposed conductive layer on the substrate, wherein the polymer layer has a thickness of about 3 microns to about 7 microns;

(b) curing the polymer layer to form a cured polymer layer having a top surface;

(c) forming a patterned masking layer atop and in contact with the top surface of the cured polymer layer;

(d) etching an exposed portion of the cured polymer layer through the patterned masking layer to form a via through the cured polymer layer to a top surface of the conductive layer; and

(e) removing the patterned masking layer.

22 . The method of claim 21 , wherein the polymer layer includes one or more polyimide compounds.

23 . The method of claim 21 , wherein the via has a width of about 1 micron to about 5 microns.

24 . The method of claim 21 , wherein the via has a sidewall profile angle of about 80 degrees and about 90 degrees.

25 . The method of claim 21 , wherein the patterned masking layer is a photoresist.

26 . The method of claim 21 , wherein the exposed portion of the cured polymer layer is etched with a plasma-based dry etching process.