Interposer via interconnect shapes with improved performance characteristics and methods of forming the same
An interposer may include a first metal trace located on a first dielectric layer, a second dielectric layer located on the first dielectric layer, a line-shaped via located in the second dielectric layer and connected to the first metal trace, and a second metal trace located on the second dielectric layer and connected to the line-shaped via.
1 . An interposer, comprising:
a plurality of dielectric layers including a first dielectric layer and a second dielectric layer stacked on the first dielectric layer;
a first redistribution interconnect structure comprising a first metal trace located on the first dielectric layer;
a second redistribution interconnect structure comprising a metal layer comprising:
a lower metal layer portion comprising a line-shaped via located in the second dielectric layer and connected to the first metal trace, wherein the line-shaped via has a horizontal cross-sectional shape that is one of an L-shape, a U-shape, or an H-shape; and
an upper metal layer portion comprising a second metal trace located on the second dielectric layer and connected to the line-shaped via, wherein a bottommost surface of the second metal trace directly contacts an uppermost surface of the second dielectric layer.
2 . The interposer of claim 1 , wherein a width of the line-shaped via is less than a width of the first metal trace and comprises a via width in a range of 10 μm to 1000 μm, and a length of the line-shaped via comprises a via length in a range of 10 μm to 1000 μm.
3 . The interposer of claim 2 , wherein the second dielectric layer is stacked on the first dielectric layer in a third direction, the first metal trace and the second metal trace extend longitudinally in a first direction perpendicular to the third direction, and the line-shaped via contacts the first metal trace and the second metal trace over an entirety of the via length of the line-shaped via and over an entirety of the via width of the line-shaped via.
4 . The interposer of claim 3 , wherein the length comprises a line length in the first direction of at least 10 μm and the width comprises a line width in a second direction perpendicular to the first direction and the third direction of not greater than 20 μm.
5 . The interposer of claim 4 , wherein the line length is greater than or equal to 3 times the line width.
6 . The interposer of claim 1 , wherein the line-shaped via has a horizontal cross-sectional shape that comprises an L-shape.
7 . The interposer of claim 1 , wherein the line-shaped via comprises:
a plurality of metal bars that are perpendicularly arranged in the same plane to have one of an L-shape, a U-shape, or an H-shape, wherein a ratio of a length to a width of at least one metal bar of the plurality of metal bars is in a range from 3:1 to 20:1.
8 . The interposer of claim 1 , wherein the first metal trace, the second metal trace and the line-shaped via constitute a redistribution layer (RDL) structure.
9 . An interposer module, comprising:
an interposer comprising:
a first redistribution interconnect structure comprising a first metal trace located on a first dielectric layer;
a second dielectric layer located on the first dielectric layer;
a second redistribution interconnect structure comprising a metal layer comprising:
a lower metal layer portion comprising a line-shaped via comprising a metal bar located in the second dielectric layer and connected to the first metal trace, wherein the line-shaped via has a horizontal cross-sectional shape that is one of an L-shape, a U-shape, or an H-shape; and
an upper metal layer portion comprising a second metal trace located on the second dielectric layer and connected to the metal bar of the line-shaped via wherein a bottommost surface of the second metal trace directly contacts an uppermost surface of the second dielectric layer; and
a plurality of semiconductor dies mounted on the interposer and electrically coupled by the interposer.
10 . The interposer module of claim 9 , wherein the metal bar comprises:
a straight metal bar, wherein a ratio of a length to a width of the straight metal bar is in a range from 3:1 to 20:1.
11 . The interposer module of claim 9 , wherein the metal bar comprises a plurality of metal bars including a first metal bar and a second metal bar, wherein the second bar is perpendicularly connected to an end of the first metal bar, and wherein a ratio of a length to a width of at least one metal bar of the plurality of metal bars is in a range from 3:1 to 20:1.
12 . The interposer module of claim 9 , wherein the metal bar comprises a plurality of metal bars including a first metal bar, a second metal bar and a third metal bar, wherein the third metal bar is parallel to the first metal bar, and the second metal bar is perpendicularly connected to at least one of:
an end of the first metal bar and to a corresponding end of the third metal bar; or
a center of the first metal bar and to a center of the third metal bar; and
wherein a ratio of a length to a width of at least one metal bar of the plurality of metal bars is in a range from 3:1 to 20:1.
13 . The interposer module of claim 9 , wherein the metal bar comprises a plurality of metal bars including a first metal bar, a second metal bar, a third metal bar and a fourth metal bar, wherein:
the third metal bar is parallel to the first metal bar,
the second metal bar is perpendicularly connected to a first end of the first metal bar and to a corresponding first end of the third metal bar,
the fourth metal bar is perpendicularly connected to a second end of the first metal bar and to a corresponding second end of the third metal bar, and
a ratio of a length to a width of at least one metal bar of the plurality of metal bars is in a range from 3:1 to 20:1.
14 . An interposer, comprising:
a polymer layer;
a first redistribution interconnect structure comprising a first metal trace in the polymer layer;
a second redistribution interconnect structure comprising a metal layer comprising:
an upper metal layer portion comprising a second metal trace on the polymer layer over the first metal trace, wherein a bottommost surface of the second metal trace directly contacts an uppermost surface of the polymer layer; and
a lower metal layer portion comprising a metal via in the polymer layer, wherein the metal via connects the first metal trace to the second metal trace, and the metal via has a horizontal cross-sectional shape that is one of an L-shape, a U-shape, or an H-shape.
15 . The interposer of claim 14 , wherein a combined thickness of the first metal trace and the metal via is substantially equal to a thickness of the polymer layer.
16 . The interposer of claim 14 , wherein the metal via has a width less than a width of the first metal trace and is in a range of 10 μm to 1000 μm and a length in a range of 10 μm to 1000 μm.
17 . The interposer of claim 14 , wherein an entirety of a bottom surface of the metal via contacts an upper surface of the first metal trace and an entirety of an upper surface of the metal via contacts the bottom surface of the second metal trace.
18 . The interposer of claim 14 , wherein the metal via comprises a line-shaped portion, and a length of the line-shaped portion is greater than or equal to 3 times a width of the line-shaped portion.
19 . The interposer of claim 14 , wherein the metal via comprises a plurality of straight metal bars.
20 . The interposer of claim 14 , further comprising:
a lower polymer layer having an uppermost surface in contact with a bottom surface of the first metal trace, wherein the first redistribution interconnect structure further comprises a lower metal via in the lower polymer layer and a width of the lower metal via is less than the width of the metal via.