Semiconductor device having interconnection lines with different linewidths and metal patterns

Patent metadata

Field	Value
Publication number	US-11270944-B2
Application number	US-202016940933-A
Country	US
Kind code	B2
Filing date	Jul 28, 2020
Priority date	Dec 16, 2019
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

A semiconductor device includes transistors on a substrate, a first interlayered insulating layer on the transistors, first and second lower interconnection lines in an upper portion of the first interlayered insulating layer, and first and second vias on the first and second lower interconnection lines, respectively. Each of the first and second lower interconnection lines includes a first metal pattern. The first lower interconnection line further includes a second metal pattern, on the first metal pattern with a metallic material different from the first metal pattern. The second metal pattern is absent in the second lower interconnection line. The second via includes first and second portions, which are in contact with respective top surfaces of the first interlayered insulating layer and the second lower interconnection line, and the lowest level of a bottom surface of the second portion is lower than that of a bottom surface of the first via.

First claim

What is claimed is:

1. A semiconductor device, comprising
transistors on a substrate;
a first interlayered insulating layer on the transistors;
a first lower interconnection line and a second lower interconnection line in an upper portion of the first interlayered insulating layer; and
a first via and a second via on the first and second lower interconnection lines, respectively,
wherein a linewidth of the first lower interconnection line is larger than a linewidth of the second lower interconnection line,
each of the first and second lower interconnection lines comprises a first metal pattern,
the first lower interconnection line further comprises a second metal pattern, on the first metal pattern and contains a metallic material different from the first metal pattern,
the second metal pattern is absent in the second lower interconnection line,
the second via comprises a first portion in contact with a top surface of the first interlayered insulating layer and a second portion in contact with a top surface of the second lower interconnection line, and
a lowest level of a bottom surface of the second portion is lower than a lowest level of a bottom surface of the first via.

2. The semiconductor device of claim 1 , wherein a highest level of the top surface of the second lower interconnection line is lower than a highest level of a top surface of the first lower interconnection line.

3. The semiconductor device of claim 1 , wherein the first metal pattern comprises a metallic material whose electron mean free path (eMFP) is smaller than 12 nm, and
the second metal pattern comprises a metallic material whose eMFP is larger than 12 nm.

4. The semiconductor device of claim 3 , wherein the first metal pattern comprises ruthenium (Ru), cobalt (Co), tungsten (W), or molybdenum (Mo), and
the second metal pattern comprises copper (Cu).

5. The semiconductor device of claim 1 , wherein the second metal pattern has a largest volume in the first lower interconnection line, and
the first metal pattern has a largest volume in the second lower interconnection line.

6. The semiconductor device of claim 1 , wherein a thickness of an upper portion of the first metal pattern of the first lower interconnection line in a horizontal direction is a first thickness,
a thickness of the first metal pattern of the second lower interconnection line in the horizontal direction is a second thickness, and
the second thickness is larger than two times the first thickness.

7. The semiconductor device of claim 1 , wherein the first metal pattern of the first lower interconnection line comprises a lower portion and a pair of upper portions vertically extended from the lower portion, and
the second metal pattern of the first lower interconnection line is in a space enclosed by the lower portion and the pair of upper portions.

8. The semiconductor device of claim 1 , wherein each of the first and second lower interconnection lines further comprises a barrier metal pattern between the first interlayered insulating layer and the first metal pattern, and
an upper portion of the barrier metal pattern is recessed to define a recess region between the first interlayered insulating layer and the first metal pattern.

9. The semiconductor device of claim 1 , wherein the first lower interconnection line further comprises a metal capping pattern covering a top surface of the first metal pattern and a top surface of the second metal pattern, and
the metal capping pattern comprises ruthenium (Ru), cobalt (Co), or graphene.

10. The semiconductor device of claim 1 , further comprising:
a second interlayered insulating layer on the first interlayered insulating layer; and
upper interconnection lines in the second interlayered insulating layer,
wherein each of the upper interconnection lines comprises a line portion, which extends in a horizontal direction, and a via portion, under the line portion,
the upper interconnection lines comprise a first upper interconnection line and a second upper interconnection line,
the via portion of the first upper interconnection line constitutes the first via, and
the via portion of the second upper interconnection line constitutes the second via.

11. The semiconductor device of claim 1 , wherein the transistors comprise gate electrodes arranged with a first pitch,
the second lower interconnection lines are arranged with a second pitch, and
the second pitch is smaller than the first pitch.

12. The semiconductor device of claim 1 , wherein the first lower interconnection line comprises a via portion as a lower portion thereof, and
the second metal pattern is absent in the via portion.

13. A semiconductor device, comprising
transistors on a substrate;
a first interlayered insulating layer on the transistors; and
a first lower interconnection line and a second lower interconnection line in an upper portion of the first interlayered insulating layer,
wherein a linewidth of the first lower interconnection line is larger than a linewidth of the second lower interconnection line,
each of the first and second lower interconnection lines comprises a first metal pattern, the first metal pattern of each of the first and second lower interconnection lines having the same height,
the first lower interconnection line further comprises a second metal pattern on the first metal pattern, the second metal pattern containing a metallic material different from the first metal pattern, the first metal pattern of the first lower interconnection line having a U-shape,
the second metal pattern has a largest volume in the first lower interconnection line,
the first metal pattern has a largest volume in the second lower interconnection line,
a highest level of a top surface of the second lower interconnection line is lower than a highest level of a top surface of the first lower interconnection line, and a top surface of the second metal pattern of the first lower interconnection line is higher than a top surface of the first metal pattern of the first lower interconnection line.

14. The semiconductor device of claim 13 , wherein the second metal pattern is absent in the second lower interconnection line.

15. The semiconductor device of claim 13 , further comprising a third lower interconnection line in an upper portion of the first interlayered insulating layer,
wherein a linewidth of the third lower interconnection line is larger than the linewidth of the first lower interconnection line,
the third lower interconnection line comprises the first metal pattern and the second metal pattern, and
a volume ratio of the second metal pattern in the third lower interconnection line is greater than a volume ratio of the second metal pattern in the first lower interconnection line.

16. The semiconductor device of claim 13 , wherein the first metal pattern comprises a metallic material whose electron mean free path (eMFP) is smaller than 12 nm, and
the second metal pattern comprises a metallic material whose eMFP is larger than 12 nm.

17. The semiconductor device of claim 13 , wherein a thickness of an upper portion of the first metal pattern of the first lower interconnection line in a horizontal direction is a first thickness,
a thickness of the first metal pattern of the second lower interconnection line in the horizontal direction is a second thickness, and
the second thickness is larger than two times the first thickness.

18. The semiconductor device of claim 13 , further comprising:
a second interlayered insulating layer on the first i

Assignees

• Samsung Electronics Co Ltd

Inventors

• Hong Wonhyuk
• Lee Jongjin
• Kim Rakhwan
• Jung Eun-Ji

Classifications

• H10W20/069

  by forming self-aligned vias or self-aligned contact plugs · CPC title

• H10W20/435

  Cross-sectional shapes or dispositions of interconnections · CPC title

• H10W20/056

  by filling conductive material into holes, grooves or trenches · CPC title

• H10W20/054

  by selectively removing parts thereof (H10W20/034 takes precedence) · CPC title

• H10W20/42

  Vias, e.g. via plugs · CPC title