# Patent

## Title
Structure design for minimizing on-chip interconnect inductance

## Abstract

A semiconductor device comprising a signal line and ground line is disclosed. The signal line comprises an opening and at least a portion of the ground line is in the opening in the signal line.

## Background
FIELD OF THE INVENTION
The invention relates to semiconductor devices, and more particularly to comprising semiconductor device structures minimizing or eliminating on-chip interconnect inductance.
BACKGROUND OF THE INVENTION
FIG. 1 illustrates a conventional cable 10 capable of carrying an electronic signal. The cable 10 comprises a core 12 which may be a solid metal such as copper. A concentric insulator layer 14, typically comprising a non-electrically conductive material such as a plastic, overlies the core 12. A concentric ground layer 16 over the insulator 14 serves as a ground path and an electromagnetic interference shield.
FIG. 2 illustrates a portion of a conventional semiconductor device comprising a first flat signal line 18, a second flat signal line 20 and a first flat ground line 22 positioned between the first signal line 18 and the second signal line 20. A second flat ground line 24 is provided on the outside edge of the first flat signal line 18. A third flat ground line 26 is provided on the outside edge of the second flat signal line 20. An insulator (not shown) may be positioned between the signal lines 18 and 20, and the ground lines 22, 24, 26.
FIG. 3 illustrates a portion of a conventional semiconductor device comprising a flat signal line 28 and an underlying flat ground layer 30. An insulator (not shown) may be interposed between the flat signal line 28 and the flat ground layer 30.
FIG. 4 illustrates a portion of a conventional semiconductor device comprising a flat signal line 32 and a first flat ground line 34 on one side of the flat signal line 32 and a second flat ground line 36 on the other side. A first flat ground layer 38 underlies the flat signal line 32, first flat ground line 34 and second flat ground line 36. An insulator (not shown) may be positioned between the signal line 32, the ground lines 34, and 36 and flat ground layer 38.
FIG. 5 illustrates a portion of a conventional semiconductor device comprising a first flat ground layer 38 underlying a first flat signal line 32, a first flat ground line 34 adjacent one side of the flat signal line 32 and a second flat ground line 36 adjacent the opposite side of the flat signal line 32. A second flat ground layer 40 overlies the flat signal line 32, first flat ground line 34 and second flat ground line 36.
SUMMARY OF THE INVENTION
Semiconductor structures capable of minimizing or eliminating on-chip interconnect inductance are provided. One embodiment of the invention comprises a semiconductor device comprising a signal line and a first ground line. The signal line comprises an opening wherein at least a portion of the first ground line is in the opening.
In another embodiment of the invention the signal line and the first ground line are on the same plane.
In another embodiment of the invention the opening extends completely through the signal line.
In another embodiment of the invention the signal line has a first outer side face and a second outer side face spaced apart by a distance equal to or less than 12 μm.
Another embodiment of the invention further comprises a dielectric material separating the signal line from the ground line.
In another embodiment of the invention the dielectric material is air.
In another embodiment of the invention the dielectric material is silicon dioxide.
In another embodiment of the invention the dielectric material has a dielectric constant ranging from 1 to 3.6.
Another embodiment of the invention further comprises a second opening with a portion of a second ground line in the opening.
Another embodiment of the invention further comprises a first plug connected to the first ground line and the first plug electrically connected to a first bond pad.
Another embodiment of the invention further comprises a second plug connected to the first ground line and the second plug electrically connected to a second bond pad.
Another embodiment of the invention further comprises a first redistribution trace electrically connected to the first bond pad and the first plug.
Another embodiment of the invention further comprises a second redistribution trace electrically connected to the second bond pad and to the second plug.
In another embodiment of invention the portion of the first ground line comprises a top face, bottom face, first side face, opposite second side face, first end face and second end face.
In another embodiment of invention the signal line surrounds at least four of the top face, bottom face, first side face, opposite second side face, first end face and second end face of the portion of the first ground line.
In another embodiment of invention the signal line surrounds each of the top face, bottom face, first side face, opposite second side face, first end face and second end face of the portion of the first ground line.
In another embodiment of invention the portion of the second ground line comprises a top face, bottom face, first side face, opposite second side face, first end face and second end face.
In another embodiment of invention the signal line surrounds at least four of the top face, bottom face, first side face, opposite second side face, first end face and second end face of the portion of the second ground line.
In another embodiment of invention the signal line surrounds all of the top face, bottom face, first side face, opposite second side face, first end face, and second end face of the portion of the second ground line.
In another embodiment of invention the signal line surrounds each of the top face, bottom face, first side face, opposite second side face, first end face and second end face of the portion of the second ground line.
Another embodiment of the invention further comprises a dielectric separating the signal line from the portion of the first ground line and the portion of the second ground line.
Another embodiment of the invention further comprises a first plug connected to the portion of the first ground line and wherein the signal line surrounds the first plug.
Another embodiment of the invention further comprises a dielectric separating the first plug from the signal line.
Another embodiment of the invention further comprises a first bond pad electrically connected to the first plug.
Another embodiment of the invention further comprises a first redistribution trace electrically connecting the first bond pad to the first plug.
Another embodiment of the invention further comprises a second plug electrically connecting the portion of a first ground line and wherein the signal line surrounds the second plug.
Another embodiment of the invention further comprises a dielectric separating the second plug from the signal line.
Another embodiment of the invention further comprises a second bond pad electrically connected to the second plug.
Another embodiment of the invention further comprises a second redistribution trace electrically connecting the second bond pad to the second plug.
Another embodiment of the invention comprises a semiconductor device comprising a signal line and at least a first and a second ground line, the signal line having at least a first opening and a second opening. At least a portion of the first ground line is in the first opening and a portion of the second ground line is in the second opening.
Other embodiments of the invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.



BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
FIG. 1 illustrates a conventional cable.
FIG. 2 illustrates a portion of a conventional semiconductor device.
FIG. 3 illustrates a portion of a conventional semiconductor device.
FIG. 4 illustrates a portion of a conventional semiconductor device.
FIG. 5 illustrates a portion of a conventional semiconductor device.
FIG. 6A illustrates a top view of one embodiment of a semiconductor device.
FIG. 6B is a sectional view taken along line 6B-6B′ of FIG. 6A.
FIG. 7A illustrates a top view of an alternative embodiment of a semiconductor device.
FIG. 7B is a sectional view taken along line 7B-7B′ of FIG. 6A.
FIG. 8A illustrates a plan view of a further alternative embodiment of a semiconductor device.
FIG. 8B is a sectional view taken along line 8B-8B′ of FIG. 8A.
FIG. 9A illustrates a plan view of a yet alternative embodiment of a semiconductor device.
FIG. 9B is a sectional view taken along line 9B-9B′ of FIG. 9A.
FIG. 10 shows a top view of another embodiment of a semiconductor device.
FIG. 11 illustrates a top view of yet another embodiment of a semiconductor device.
FIG. 12 shows a top view of further another embodiment of a semiconductor device.
FIG. 13 illustrates a top view of yet further another embodiment of a semiconductor device.



DETAILED DESCRIPTION OF THE INVENTION
The following description of various embodiment(s) of the invention is exemplary in nature and is in no way intended to limit the invention, its application, or uses.
FIG. 6A illustrates a top view of a portion of a semiconductor device 200. FIG. 6B is a sectional view taken along line 6B-6B′ of FIG. 6A. Referring to FIG. 6A and FIG. 6B, the semiconductor device 200 comprises a portion of a ground line 50 positioned in an opening 55 formed in a signal line 54. The signal line 54 may be utilized to carry an electronic signal, such as a video, graphic, audio, data signal or the like. The portion of the ground line 50 comprises a first end face 58 and an opposite second end face 60, as shown in FIG. 6A. The portion of the ground line 50 also comprises a first side 62, a second opposite side 64, a top face 66 and a bottom face 68, as seen in FIG. 6B. The signal line 54 comprises a top face 104, comprising a substantially flat portion, and a bottom face 106, as shown in FIG. 6B. The signal line 54 comprises a first outer side 100 and an opposite second outer side 102. The signal line 54 and the portion of the ground line 50 may be formed on a first intermetal dielectric 70, as shown in FIG. 6B. The signal line 54 and the portion of the ground line 50 may be separated by an opening 55 formed in the signal line which is filled with a dielectric such as air 52.
FIG. 7A illustrates a top view of an alternative embodiment of a semiconductor device. FIG. 7B is a sectional view taken along line 7B-7B′ of FIG. 7A. Note that the same or similar elements use the same reference numbers as that of the previously described embodiment and may not be all described herein. Referring now to FIGS. 7A and 7B, the semiconductor device 200 comprises a portion of a ground line 50 positioned in an opening 55 formed in a signal line 54. The signal line 54 may be utilized to carry an electronic signal, such as a video, graphic, audio, data signal or the like. The signal line 54 comprises a top face 104, comprising a substantially flat portion, and a bottom face 106, as shown in FIG. 7B. The signal line 54 comprises a first outer side 100 and an opposite second outer side 102. The signal line 54 and the portion of the ground line 50 may be formed on a first intermetal dielectric 70, as shown in FIG. 7B. The opening is filled with dielectric materials, such that the signal line 54 and the portion of the ground line 50 is separated by a solid dielectric 56, such as silicon dioxide.
FIG. 8A illustrates a plan view of a further alternative embodiment of a semiconductor device. FIG. 8B is a sectional view taken along line 8B-8B′ of FIG. 8A. Note that the same or similar elements use the same reference numbers as that of the previously described embodiment and may not be all described herein. Referring now to FIGS. 8A and 8B, the semiconductor device 200 comprises a portion of a ground line 50 positioned in an opening 55 formed in a signal line 54. The signal line 54 may be utilized to carry an electronic signal, such as a video, graphic, audio, data signal or the like. The signal line 54 comprises a top face 104, comprising a substantially flat portion, and a bottom face 106, as shown in FIG. 8A. The signal line 54 and the portion of the ground line 50 may be formed on a first intermetal dielectric 70, as shown in FIG. 8B. Dielectric materials, such as silicon dioxide, are blanketly formed in the opening 55, and on the ground line 50 and the signal line 54, such that the signal line 54 and the portion of the ground line 50 are separated by an insulator 56. A first ground plug or via 74 (i.e., a metal filled opening in a dielectric layer, as shown in FIG. 8B, extends from the portion of the ground line 50 to a first bond pad 76 through the insulator 56. A second ground plug or via 77 (FIG. 8B) extends from the portion of the ground line 50 to a second bond pad 78.
FIG. 9A illustrates a plan view of a yet alternative embodiment of a semiconductor device. FIG. 9B is a sectional view taken along line 9B-9B′ of FIG. 9A. Note that the same or similar elements use the same reference numbers as that of the previously described embodiment and may not be all described herein. Referring now to FIGS. 9A and 9B, a first signal line 54 is disposed on a first intermetal dielectric layer 108 (FIG. 9B) with an opening 55 filled with a dielectric layer 56. A ground line 50 is over the first signal line 54 with the dielectric layer 56 interposed therebetween. In addition, a second signal line 54a is over the ground line 50 with another dielectric layer 56a interposed therebetween. Note that the dielectric layers 56 and 56a separate the second signal lines 54 and 54a and the ground line 50. A first redistribution trace 80 (FIG. 9B) is connected to the first ground via 74 and to a third ground via 84 extending from the first redistribution trace 80 through a second intermetal dielectric layer 72, as shown in FIG. 9B. The third ground via 84 is electrically connected to the first bond pad 76. Similarly, a second redistribution trace 82 is connected to the second ground via 77 and to a fourth ground via 86, extending through the second intermetal dielectric layer 72, as shown in FIG. 9B. The fourth ground via 86 is electrically connected to the second bond pad 78. The first ground via 74 and the second ground via 77 are electrically connected to the ground line 50. The dielectric layers 56, 70, 72, 108 may be a low dielectric material having a dielectric constant ranging from 1 to 3.6.
FIG. 10 illustrates a top view of a portion of a semiconductor device 200 comprising a plurality of openings 55 formed in a signal line 54 and a portion of a ground line 50 received in each of the openings 55. An insulator 56 separates the portion of the ground line 50 and the signal line 54.
FIG. 11 is a top view of a portion of a semiconductor device 200 comprising a plurality of portions of a ground line 50 each received in an opening 55 formed in a signal line 54. Again, an insulator 56, such as silicon dioxide, separates the portion of the ground line 50 from the signal line 54.
FIG. 12 illustrates a top view of a portion of a semiconductor device 200 comprising openings 55 formed in a signal line 54 and a portion of a ground line 50 received in each of the openings 55 of another embodiment of the invention. In this embodiment, the openings are neighboring opposite sidewalls of the signal line 54. An insulator 56 separates the portion of the ground line 50 and the signal line 54.
FIG. 13 is a top view of a portion of a semiconductor device 200 comprising a plurality of portions of a ground line 50 each received in an opening 55 formed in a signal line 54 of further another embodiment of the invention. Again, the openings 55 are neighboring two opposite sidewalls of the signal line 54, and an insulator 56, such as silicon dioxide, separates the portion of the ground line 50 from the signal line 54.
The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. such variations are not to be regarded as a departure from the spirit and scope of the invention.

## Claims

1. A semiconductor device comprising;
a first signal line and a ground line, wherein only the ground line is embedded in an opening of the first signal line and there is no other ground line neighboring the first signal line.

2. The semiconductor device as claimed in claim 1, wherein the first signal line and the ground line are in the same plane.

3. The semiconductor device as claimed in claim 1, further comprising a dielectric material separating the first signal line from the ground line.

4. The semiconductor device as claimed in claim 1, further comprising a plug connected to the ground line and the plug electrically connected to a first bond pad.

5. The semiconductor device as claimed in claim 4, further comprising a redistribution trace electrically connected to the first bond pad and the plug.

6. The semiconductor device as claimed in claim 1, wherein the opening is neighboring a side of the first signal line.

7. The semiconductor device as claimed in claim 1, further comprising a second signal line in the opening, separated from the ground line.

8. The semiconductor device as claimed in claim 7, wherein the ground line is separated from the second signal line by dielectric material.

9. A semiconductor device, comprising;
an interconnect dielectric layer;
a first signal line disposed on the interconnect dielectric layer; and
only a ground line embedded in an opening of the first signal line and on the interconnect dielectric layer, wherein the first signal line and the ground line are isolated, and there is no other ground line neighboring the first signal line.

10. The semiconductor device as claimed in claim 9, further comprising a plug connected to the ground line and the plug electrically connected to a first bond pad.

11. The semiconductor device as claimed in claim 9, wherein the opening is neighboring a side of the first signal line.

12. The semiconductor device as claimed in claim 9, further comprising a dielectric material separating the first signal line from the ground line.