Replacement via and buried or backside power rail

1 . An integrated circuit comprising:

a first sub-fin;

a second sub-fin laterally spaced from the first sub-fin by a distance of 100 nm or less along a first direction;

a first transistor device over the first sub-fin and having a first contact;

a second transistor device over the second sub-fin and having a second contact;

a continuous and monolithic body of conductive material extending vertically between the first and second transistor devices and the first and second sub-fins, the continuous and monolithic body of conductive material having (i) a first upper portion between the first and second transistor devices, (ii) a second upper portion spaced from the first upper portion along a second direction different from the first direction, and (iii) a lower portion at least between the first and second sub-fins and coupled to the first upper portion and the second upper portion, the lower portion being at least 1.2 times wider than the first and second upper portions along the first direction;

a continuous conformal layer that extends along a sidewall of the lower portion of the body, a sidewall of the first upper portion of the body, and a sidewall of the second upper portion of the body; and

a conductive interconnect feature connecting the first upper portion of the body to at least one of the first and second contacts.

2 . The integrated circuit of claim 1 , wherein the continuous conformal layer does not separate the second upper portion and the lower portion.

3 . The integrated circuit of claim 1 , wherein a first end of the second upper portion of the body is coupled to a power supply, and a second end of the second upper portion of the body is conjoined to the lower portion of the body, and wherein the second upper portion of the body is configured to supply power from the power supply to the lower portion of the body.

4 . The integrated circuit of claim 3 , wherein the lower portion is configured to supply the power from the second upper portion to the at least one of the first and second contacts, through the first upper portion and the conductive interconnect feature.

5 . The integrated circuit of claim 1 , wherein each of the first sub-fin, the lower portion of the body of conductive material, and the second sub-fin are at least partially in a layer of dielectric material, and the continuous conformal layer is between the dielectric material and at least the lower portion of the continuous body.

6 . The integrated circuit of claim 1 , wherein the body of conductive material comprises a buried or backside power rail, and the continuous conformal layer is a barrier layer.

7 . The integrated circuit of claim 1 , wherein the first or second transistor includes a source region or drain region, and the first or second contact is on the source region or drain region.

8 . The integrated circuit structure of claim 1 , wherein the continuous conformal layer comprises one or more of cobalt, nickel, ruthenium, molybdenum, manganese, titanium, tungsten, tantalum, nitrogen, silicon.

9 . The integrated circuit structure of claim 1 , wherein the body of conductive material comprises one or more of copper, ruthenium, molybdenum, tin, indium, antimony, or bismuth.

10 . An integrated circuit structure comprising:

a substrate, and one or more dielectric layers above the substrate;

one or more transistors on the substrate and spaced from one another along a first direction;

a first recess at least in part within the substrate, and a second recess and a third recess at least in part within the one or more dielectric layers, the second and third recesses spaced from one another along a second direction different from the first direction;

a continuous monolithic body of conductive material within the first recess, the second recess, and the third recess; and

a conductive interconnect feature to couple the second recess with a terminal of a transistor of the one or more transistors.

11 . The integrated circuit structure of claim 10 , further comprising:

a continuous and conformal layer on walls of the first recess, the second recess, and the third recess.

12 . The integrated circuit structure of claim 10 , wherein:

the second recess is conjoined with the first recess at one end and is coupled to the terminal of the transistor at another end; and

the third recess is conjoined with the first recess at one end and is coupled to a power supply terminal at another end.

13 . The integrated circuit structure of claim 10 , wherein the transistor of the one or more transistors is a first transistor, and wherein the integrated circuit structure further comprises:

a first region within the substrate, the first region underneath a channel region of the first transistor; and

a second region within the substrate, the second region underneath a channel region of a second transistor of the one or more transistors,

wherein the first recess is laterally between the first region and the second region.

14 . The integrated circuit structure of claim 13 , wherein the first region and the second region are a first sub-fin region of the first transistor and a second sub-fin region of the second transistor, respectively.

15 . The integrated circuit structure of claim 10 , wherein the terminal of the transistor is one of a source terminal or a drain terminal.

16 . The integrated circuit structure of claim 10 , further comprising:

a continuous and conformal layer on walls of the first recess, the second recess, and the third recess, wherein the continuous and conformal layer comprises one or more of cobalt, nickel, ruthenium, molybdenum, manganese, titanium, tungsten, tantalum, nitrogen, silicon.

17 . The integrated circuit structure of claim 10 , wherein the continuous monolithic body of conductive material comprises one or more of copper, ruthenium, molybdenum, tin, indium, antimony, or bismuth.

18 . An integrated circuit comprising:

a first semiconductor device having a first sub-fin and one or more first semiconductor bodies over the first sub-fin and extending from a first source or drain region to a second source or drain region in a first direction;

a second semiconductor device having a second sub-fin and one or more second semiconductor bodies over the second sub-fin and extending from a third source or drain region to a fourth source or drain region in the first direction, the third source or drain region laterally spaced from the first source or drain region along a second direction substantially orthogonal to the first direction, and the fourth source or drain region laterally spaced from the second source or drain region along the second direction;

a continuous and monolithic body of conductive material extending vertically between the first and second semiconductor devices along the second direction, the body of conductive material having a first upper portion extending vertically between the first and third source or drain regions, a second upper portion extending vertically between the second and fourth source or drain regions and spaced from the first portion along the first direction, and a lower portion between the first and second sub-fins and coupled to the first upper portion and the second upper portion, the lower portion being wider than the first upper portion and wider than the second upper portion;

a conductive interconnect feature contacting the first upper portion of the body; and

a contact extending between the conductive interconnect feature and a top surface of the first source or drain region or the third source or drain region.

19 . The integrated circuit of claim 18 , further comprising a continuous conformal layer that extends along a sidewall of the lower portion of the body, a sidewall of the first upper portion of the body, and a sidewall of the second upper portion of the body.

20 . The integrated circuit of claim 19 , wherein the body of conductive material comprises a buried or backside power rail, and the continuous conformal layer is a barrier layer.