The present disclosure relates to a semiconductor integrated circuit device including a standard cell with a transistor having a fin structure.
A standard cell design has been known as a method of forming a semiconductor integrated circuit on a semiconductor substrate. The standard cell design refers to a method of designing a large-scale integrated circuit (LSI) chip by providing in advance, as standard cells, unit logic elements having particular logical functions (for example, an inverter, a latch, a flip-flop, and a full adder), laying out those standard cells on a semiconductor substrate, and connecting those standard cells together through a routing process.
Recently, it has been proposed to utilize transistors with a fin structure (hereinafter referred to as “fin transistors”) in the field of semiconductor devices.
Japanese Unexamined Patent Application Publication No. 2008-219002 teaches, as an improvement for the process step of making such a fin structure, performing selective etching by forming the fin in the same direction as the crystal-growing direction of a silicon substrate.
In such a fin structure, the fin is not necessarily formed uniformly along its entire length. That is to say, the width of the fin is not necessarily the same in the length direction, but varies to some extent. In particular, the fin width tends to taper toward the terminal portion thereof. Thus, if a transistor is formed near the terminal portion of the fin, chances of achieving the desired performance are slim.
If a wire or contact is connected to the terminal portion of the fin, the degree of electrical contact between the fin and the wire or contact may decrease due to such a deformation of the terminal portion of the fin, or mask misalignment of the wire or contact, resulting in a variation in resistance characteristic. This variation may cause a decrease in the yield of semiconductor chips.
In view of the foregoing background, it is therefore an object of the present disclosure to reduce, in a semiconductor integrated circuit device including a standard cell with a fin transistor, the influence caused by such tapering of the terminal portion of the fin and eventually reduce a variation in performance between the devices.
An aspect of the present disclosure provides a semiconductor integrated circuit device including a standard cell having a fin extending in a first direction. The standard cell includes: an active transistor including the fin and a gate line extending in a second direction perpendicular to the first direction and provided on the fin; and a dummy transistor including the fin and a dummy gate line provided on the fin in parallel with the gate line. The active transistor shares its source or drain with the dummy transistor.
According to this aspect of the present disclosure, by providing the dummy transistor, the source or drain of the active transistor may be arranged distant from the terminal portion of the fin. That is to say, the node of the active transistor is not positioned at the terminal portion of the fin that is highly likely to have a narrower fin width. This allows for eliminating the influence caused by tapering of the terminal portion of the fin on the active transistor, thus reducing the variation in performance between the active transistors.
The present disclosure allows for reducing, in a semiconductor integrated circuit device including a standard cell with a fin transistor, the influence caused by tapering of the terminal portion of the fin. This thus allows for reducing a variation in performance between the semiconductor integrated circuit devices.
Embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. In the following description of embodiments, it is assumed that a semiconductor integrated circuit device includes a plurality of standard cells, at least some of which includes a fin transistor.
Also, in this specification, a transistor which contributes to a logical function of the standard cells will be hereinafter referred to as an “active transistor,” and a transistor other than such an active transistor, i.e., a transistor which does not contribute to any logical function of the standard cells will be hereinafter referred to as a “dummy transistor.”
As illustrated in
A ground line 8a supplying a ground potential is disposed at the lower end of the standard cell 1 so as to extend in the lateral direction on the paper. A power supply line 8b supplying a power supply potential is disposed at the upper end of the standard cell 1 so as to extend in the lateral direction on the paper. Dummy gate lines 9a and 9b are respectively disposed at the left and right ends of the standard cell 1 so as to extend in the vertical direction on the paper.
In addition, dummy transistors D1 and D2 are further formed on the fin 11. That is to say, the fin 11 and a dummy gate line 14 provided on the fin 11 in parallel with the gate line 12 constitute the dummy transistor D1. The n-channel transistor N1 shares its source, to which the ground potential is supplied as an exemplary power supply potential, with the dummy transistor D1. Also, the fin 11 and a dummy gate line 15 provided on the fin 11 in parallel with the gate line 13 constitute the dummy transistor D2. The n-channel transistor N2 shares its source, to which the ground potential is supplied, with the dummy transistor D2. The sources, drains, and gates of the dummy transistors D1 and D2 are all connected to the ground line 8a functioning as an exemplary power supply line.
The n-channel transistor N1 shares its source with the dummy transistor D1, and shares its drain with the n-channel transistor N2 functioning as a third transistor. The n-channel transistor N2 shares its source with the dummy transistor D2, and shares its drain with the n-channel transistor N1 functioning as a third transistor. That is to say, in the layout design of
According to the layout design of
It is not necessary to provide the dummy transistors D1 and D2 if the logical function of the NOR circuit of
However, in the layout design of
In this embodiment, each n-channel transistor functioning as an active transistor shares its source with its associated dummy transistor. However, the present disclosure is not limited thereto. For example, each active transistor may share its drain with its associated dummy transistor. Alternatively, each p-channel transistor functioning as an active transistor may share one of its source or drain with its associated dummy transistor. In that case, the other of the active transistor's source or drain shared with the dummy transistor may, or need not, be shared with another dummy transistor.
As illustrated in
Also, gate lines 17, 12, 13, and 18 extending in the vertical direction on the paper and provided on the fin 16 respectively constitute, together with the fin 16, p-channel transistors P1, P2, P3, and P4 functioning as active transistors. Also, the gate lines 17, 12, 13, and 18 extending over the fin 22 respectively constitute, together with the fin 22, p-channel transistors P1a, P2a, P3a, and P4a.
A ground line 8a supplying a ground potential is disposed at the lower end of the standard cell 2 so as to extend in the lateral direction on the paper. A power supply line 8b supplying a power supply potential is disposed at the upper end of the standard cell 2 so as to extend in the lateral direction on the paper. Dummy gate lines 9a and 9b are respectively disposed at the left and right ends of the standard cell 2 so as to extend in the vertical direction on the paper.
In addition, dummy transistors D1 and D2 are further formed on the fin 11, and dummy transistors D1a and D2a are further formed on the fin 21. That is to say, the fin 11 and a dummy gate line 14 provided on the fin 11 in parallel with the gate line 12 constitute the dummy transistor D1. Also, the fin 11 and a dummy gate line 15 provided on the fin 11 in parallel with the gate line 13 constitute the dummy transistor D2. The n-channel transistor N1 shares its source, to which the ground potential is supplied, with the dummy transistor D1. The n-channel transistor N2 shares its source, to which the ground potential is supplied, with the dummy transistor D2. Furthermore, the fin 21 and a dummy gate line 14 provided on the fin 21 constitute the dummy transistor D1a. Also, the fin 21 and a dummy gate line 15 extending over the fin 21 constitute the dummy transistor D2a. The n-channel transistor N1a shares its source, to which the ground potential is supplied, with the dummy transistor D1a. The n-channel transistor N2a shares its source, to which the ground potential is supplied, with the dummy transistor D2a. The source, drain, and gate of each of the dummy transistors D1, D2, D1a, and D2a are all connected to the ground line 8a.
The n-channel transistor N1 shares its source with the dummy transistor D1, and shares its drain with the n-channel transistor N2. The n-channel transistor N2 shares its source with the dummy transistor D2, and shares its drain with the n-channel transistor N1. The n-channel transistor N1a shares its source with the dummy transistor D1a, and shares its drain with the n-channel transistor N2a. The n-channel transistor N2a shares its source with the dummy transistor D2a, and shares its drain with the n-channel transistor N1a. That is to say, in the layout design of
According to the layout design of
However, in the layout design of
In the layout design of
That is to say, in a region DN1, a fin 31 and a dummy gate line 33 constitute a dummy transistor sharing its source with the n-channel transistor N1, and a fin 32 and the dummy gate line 33 constitute a dummy transistor with which the n-channel transistor N1a shares its source. In a region DN2, the fin 31 and a dummy gate line 34 constitute a dummy transistor with which the n-channel transistor N1 shares its drain, and the fin 32 and the dummy gate line 34 constitute a dummy transistor with which the n-channel transistor N1a shares its drain. The fin 31 and a dummy gate line 35 constitute a dummy transistor with which the n-channel transistor N2 shares its drain, and the fin 32 and the dummy gate line 35 constitute a dummy transistor with which the n-channel transistor N2a shares its drain. In a region DN3, the fin 31 and a dummy gate line 36 constitute a dummy transistor with which the n-channel transistor N2 shares its source, and the fin 32 and the dummy gate line 36 constitute a dummy transistor with which the n-channel transistor N2a shares its source.
In a region DP1, a fin 37 and a dummy gate line 39 constitute a dummy transistor with which the p-channel transistor P1a shares its drain, and a fin 38 and the dummy gate line 39 constitute a dummy transistor with which the p-channel transistor P1 shares its drain. In a region DP2, the fin 37 and a dummy gate line 40 constitute a dummy transistor with which the p-channel transistor P4a shares its drain, and the fin 38 and the dummy gate line 40 constitute a dummy transistor with which the p-channel transistor P4 shares its drain.
The layout design of
(Other Exemplary Layout Designs)
In the foregoing description of embodiments, a NOR circuit has been described as an exemplary circuit according to the present disclosure, but this is only an exemplary embodiment of the present disclosure. For example, the present disclosure is also applicable in the same or similar manner to semiconductor integrated circuit devices performing other logical functions such as inverters, NAND gates, and flip-flops.
In the foregoing description of embodiments, if the dummy transistor is, e.g., an n-channel transistor, a ground potential is supplied to its gate to fix the gate potential. However, the present disclosure is not limited to this configuration. Alternatively, another configuration not contributing to any logical function may be adopted. For example, in the case of an n-channel transistor, a power supply potential may be supplied to its gate, and a ground potential may be supplied to its source and drain.
The present disclosure allows for reducing, in a semiconductor integrated circuit device including a standard cell having a fin transistor, the influence caused by tapering of the terminal portion of the fin. Thus, this is useful for reducing a variation in performance between the semiconductor integrated circuit devices.
Number | Date | Country | Kind |
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2013-173739 | Aug 2013 | JP | national |
This is a Continuation of U.S. patent application Ser. No. 17/744,141, filed on May 13, 2022, now U.S. Pat. No. 11,764,217, which is a Continuation of U.S. patent application Ser. No. 17/039,051, filed on Sep. 30, 2020, now U.S. Pat. No. 11,362,088, which is a Continuation of U.S. patent application Ser. No. 16/211,919, filed on Dec. 6, 2018, now U.S. Pat. No. 10,833,075, which is a Continuation of U.S. patent application Ser. No. 15/863,107, filed on Jan. 5, 2018, now U.S. Pat. No. 10,181,469, which is a Continuation of U.S. patent application Ser. No. 15/049,680, filed on Feb. 22, 2016, now U.S. Pat. No. 9,899,381, which is a Continuation of International Patent Application No. PCT/JP2014/002237, filed on Apr. 21, 2014, which claims priority to Japanese Patent Application No. 2013-173739, filed on Aug. 23, 2013. The entire disclosures of these applications are hereby incorporated by reference.
Number | Name | Date | Kind |
---|---|---|---|
6909135 | Nii et al. | Jun 2005 | B2 |
7456481 | Inaba | Nov 2008 | B2 |
7812373 | Bauer et al. | Oct 2010 | B2 |
8004042 | Yang et al. | Aug 2011 | B2 |
8395220 | Chang | Mar 2013 | B2 |
8519462 | Wang | Aug 2013 | B2 |
8561003 | Kawa et al. | Oct 2013 | B2 |
8739104 | Penzes | May 2014 | B1 |
8786028 | Hong et al. | Jul 2014 | B2 |
8848423 | Chung | Sep 2014 | B2 |
8907429 | Yoshida | Dec 2014 | B2 |
9093304 | Koldiaev | Jul 2015 | B2 |
9111801 | Zhang | Aug 2015 | B2 |
9196540 | Chen | Nov 2015 | B2 |
9899381 | Shimbo | Feb 2018 | B2 |
10181469 | Shimbo | Jan 2019 | B2 |
10833075 | Shimbo | Nov 2020 | B2 |
11764217 | Shimbo | Sep 2023 | B2 |
20050136582 | Aller et al. | Jun 2005 | A1 |
20070004147 | Toubou et al. | Jan 2007 | A1 |
20070210405 | Tsutsumi | Sep 2007 | A1 |
20080203468 | Cheng et al. | Aug 2008 | A1 |
20080315258 | Masuda et al. | Dec 2008 | A1 |
20090014811 | Becker et al. | Jan 2009 | A1 |
20090041406 | Schulz | Feb 2009 | A1 |
20090230483 | Mizumura et al. | Sep 2009 | A1 |
20100006896 | Uemura | Jan 2010 | A1 |
20100127333 | Hou et al. | May 2010 | A1 |
20100187699 | Nishimura et al. | Jul 2010 | A1 |
20100287518 | Becker | Nov 2010 | A1 |
20110018064 | Doornbos | Jan 2011 | A1 |
20110073953 | Nishimura et al. | Mar 2011 | A1 |
20110186932 | Mizumura et al. | Aug 2011 | A1 |
20120273899 | Wann et al. | Nov 2012 | A1 |
20130027083 | Ando et al. | Jan 2013 | A1 |
20130126978 | Becker et al. | May 2013 | A1 |
20130148409 | Chung | Jun 2013 | A1 |
20130334610 | Moroz et al. | Dec 2013 | A1 |
20140061801 | Doornbos et al. | Mar 2014 | A1 |
20140097493 | Baek et al. | Apr 2014 | A1 |
20140117454 | Liu et al. | May 2014 | A1 |
20140131813 | Liaw | May 2014 | A1 |
20140145263 | Cheng et al. | May 2014 | A1 |
20140167172 | Chen et al. | Jun 2014 | A1 |
20140252476 | Chang et al. | Sep 2014 | A1 |
20140258961 | Ke et al. | Sep 2014 | A1 |
20140264610 | Yang et al. | Sep 2014 | A1 |
20140327081 | Hsieh et al. | Nov 2014 | A1 |
20150008524 | Hung et al. | Jan 2015 | A1 |
20150035568 | Peng et al. | Feb 2015 | A1 |
20150041924 | Moroz | Feb 2015 | A1 |
20150054078 | Xie | Feb 2015 | A1 |
Number | Date | Country |
---|---|---|
09-289251 | Nov 1997 | JP |
2005-197685 | Jul 2005 | JP |
2007-012855 | Jan 2007 | JP |
2008-219002 | Sep 2008 | JP |
2009-218499 | Sep 2009 | JP |
2010-016258 | Jan 2010 | JP |
2010-021469 | Jan 2010 | JP |
2010-123947 | Jun 2010 | JP |
2014-220501 | Nov 2014 | JP |
2013106799 | Jul 2013 | WO |
Entry |
---|
International Search report dated May 27, 2014, issued in corresponding International Application No. PCT/JP2014/002237. (w/ partial English translation). |
Non-Final Office Action issued in U.S. Appl. No. 15/049,680, dated Apr. 4, 2017. |
Notice of Allowance issued in U.S. Appl. No. 15/049,680, dated Oct. 13, 2017. |
Japanese Notification of Reasons for Refusal, issued in Japanese Patent Application No. 2018-010604, mailed Nov. 13, 2018; with English translation. |
Non-Final Office Action issued in U.S. Appl. No. 15/863,107, dated Apr. 19, 2018. |
Notice of Allowance issued in U.S. Appl. No. 15/863,107, dated Sep. 6, 2018. |
Non-Final Office Action issued in U.S. Appl. No. 16/211,919, dated Apr. 1, 2020. |
Notice of Allowance issued in U.S. Appl. No. 16/211,919, dated Jul. 17, 2020. |
Non-Final Office Action issued in U.S. Appl. No. 17/039,051, dated Oct. 14, 2021. |
Notice of Allowance issued in U.S. Appl. No. 17/039,051, dated Feb. 22, 2022. |
Non-Final Office Action issued in U.S. Appl. No. 17/744,141, dated Mar. 2, 2023. |
Notice of Allowance issued in U.S. Appl. No. 17/744,141, dated May 25, 2023. |
Number | Date | Country | |
---|---|---|---|
20230387116 A1 | Nov 2023 | US |
Number | Date | Country | |
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Parent | 17744141 | May 2022 | US |
Child | 18450146 | US | |
Parent | 17039051 | Sep 2020 | US |
Child | 17744141 | US | |
Parent | 16211919 | Dec 2018 | US |
Child | 17039051 | US | |
Parent | 15863107 | Jan 2018 | US |
Child | 16211919 | US | |
Parent | 15049680 | Feb 2016 | US |
Child | 15863107 | US | |
Parent | PCT/JP2014/002237 | Apr 2014 | WO |
Child | 15049680 | US |