Semiconductor integrated circuit device
The layout of termination cells with fork-sheet transistors in semiconductor integrated circuits addresses manufacturing variations and improves reliability by exposing specific nanosheet surfaces and using dummy gate wirings, enhancing yield and area efficiency.
Patent Information
- Application Number
- JP2021552400
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2019-10-18
- Filing Date
- 2020-10-13
- Publication Date
- 2025-01-08
- Estimated Expiration
- 2040-10-13
AI Technical Summary
The increasing integration and reduced operating voltage of transistors in semiconductor integrated circuits lead to excessive off-state current and significant power consumption, necessitating a shift from planar to three-dimensional transistor structures, particularly nanosheet FETs with fork-shaped gate electrodes, but the layout and structure of termination cells using these transistors have not been adequately addressed.
A layout is provided for a semiconductor integrated circuit device incorporating termination cells with fork-sheet transistors, where standard cells with and without logic functions are arranged to suppress manufacturing variations by exposing specific nanosheet surfaces and using dummy gate wirings to stabilize the layout pattern.
This layout suppresses manufacturing variations, improves yield, and enhances reliability by regularizing the layout pattern of cells, particularly in termination cells, thereby optimizing the performance and area efficiency of semiconductor integrated circuits.
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Abstract
Description
[Technical field]
[0001] The present disclosure relates to a semiconductor integrated circuit device including a standard cell (hereinafter, also simply referred to as a cell, as appropriate) that includes a nanosheet field effect transistor (FET).
[0002] The standard cell method is known as a method for forming semiconductor integrated circuits on a semiconductor substrate. The standard cell method is a method for designing an LSI chip by preparing basic units with specific logical functions (e.g. inverters, latches, flip-flops, full adders, etc.) as standard cells in advance, arranging multiple standard cells on a semiconductor substrate, and connecting these standard cells with wiring.
[0003] Furthermore, transistors, which are the basic building blocks of LSIs, have achieved increased integration, lower operating voltages, and faster operating speeds through the reduction of gate length (scaling). In recent years, however, excessive scaling has caused problems with off-current and the resulting dramatic increase in power consumption. To solve this problem, there has been active research into three-dimensional transistors, in which the transistor structure has been changed from the conventional planar type to a three-dimensional type. Nanosheet FETs (nanowire FETs) are one type of three-dimensional transistor that has attracted attention.
[0004] Among nanosheet FETs, a fork sheet transistor with a fork-shaped gate electrode has been proposed. Non-Patent Document 1 discloses a layout of an SRAM memory cell using a fork sheet transistor, which realizes a reduction in the area of a semiconductor integrated circuit device (semiconductor memory device). [Prior art documents] [Non-patent literature]
[0005] [Non-Patent Document 1] P. Weckx et al., “Stacked nanosheet fork architecture for SRAM design and device co-optimization toward 3nm”, 2017 IEEE International Electron Devices Meeting (IEDM), December 2017, IEDM17-505~508 Summary of the Invention [Problem to be solved by the invention]
[0006] In this specification, a nanosheet FET having a fork-shaped gate electrode is referred to as a fork-sheet transistor following the conventional technology.
[0007] Here, the standard cells include cells having no logical function, in addition to cells having a logical function such as a NAND gate or a NOR gate (hereinafter, appropriately referred to as logic cells). An example of a cell having no logical function is a "termination cell". A "termination cell" is a cell that does not contribute to the logical function of a circuit block and is used to terminate the circuit block. By arranging the termination cell, it is possible to suppress the variation in the finished shape of the layout pattern of the cells located inside the termination cell, thereby suppressing the manufacturing variation of the semiconductor integrated circuit device, improving the yield, and improving the reliability.
[0008] So far, no specific studies have been made on the structure of a termination cell using a fork sheet transistor or the layout of a semiconductor integrated circuit device including a termination cell using a fork sheet transistor.
[0009] The present disclosure provides a layout for a semiconductor integrated circuit device that includes termination cells using fork sheet transistors. [Means for solving the problem]
[0010] In a first aspect of the present disclosure, a semiconductor device includes a plurality of cell rows each including a plurality of standard cells arranged in a first direction, and a first cell row, which is one of the plurality of cell rows, includes a first standard cell having a logic function and a second standard cell arranged at least on one of both ends of the first cell row and having no logic function. The first standard cell includes a first region, which is a region for forming a transistor of a first conductivity type, a second region, which is a region for forming a transistor of a second conductivity type different from the first conductivity type and adjacent to the first region in a second direction perpendicular to the first direction, a first nanosheet extending in the first direction and formed in the first region, a second nanosheet extending in the first direction and formed in the second region, a first gate wiring extending in the second direction and surrounding the periphery of the first nanosheet in the second direction and in a third direction perpendicular to the first and second directions, and a second gate wiring extending in the second direction and surrounding the periphery of the second nanosheet in the second and third directions. The second standard cell includes a third nanosheet extending in the first direction and formed at the same position as the first nanosheet in the second direction, a fourth nanosheet extending in the first direction and formed at the same position as the second nanosheet in the second direction, a first dummy gate wiring extending in the second direction and surrounding the periphery of the third nanosheet in the second and third directions, and a second dummy gate wiring extending in the second direction and surrounding the periphery of the fourth nanosheet in the second and third directions. The first nanosheet has a first side surface, which is one side in the second direction, exposed from the first gate wiring. The second nanosheet has a second side surface, which is one side in the second direction, exposed from the second gate wiring. The third nanosheet has a first side surface in the second direction exposed from the first dummy gate wiring. The fourth nanosheet has a second side surface in the second direction exposed from the second dummy gate wiring.
[0011] According to this embodiment, the second standard cell having no logic function is arranged at least on one of both ends of the first cell row in which the first standard cell having the logic function is arranged. The first standard cell includes a first and a second nanosheet, and a first and a second gate wiring that respectively surrounds the periphery in the second direction of the first and the second nanosheet. The second standard cell includes a third and a fourth nanosheet, and a third and a fourth gate wiring that respectively surrounds the periphery in the second direction of the third and the fourth nanosheet. The first and the third nanosheets have a first side surface, which is one side in the second direction, exposed from the first gate wiring and the first dummy gate wiring, respectively. The second and the fourth nanosheets have a second side surface, which is one side in the second direction, exposed from the second gate wiring and the second dummy gate wiring, respectively. That is, the first and the third nanosheets have a surface on the same side in the second direction exposed, and the second and the fourth nanosheets have a surface on the same side in the second direction exposed. This makes it possible to suppress manufacturing variations in semiconductor integrated circuit devices, improve yields, and increase reliability.
[0012] In a second aspect of the present disclosure, a semiconductor device includes a plurality of cell rows each having a plurality of standard cells arranged in a first direction and arranged in a second direction perpendicular to the first direction, the plurality of cell rows including a first cell row including a first standard cell having a logical function, and a second cell row arranged at either end of the second direction in the plurality of cell rows, the second cell row including a second standard cell not having a logical function. The first standard cell includes a first region, which is a region for forming a transistor of a first conductivity type, a second region, which is a region for forming a transistor of a second conductivity type different from the first conductivity type and adjacent to the first region in the second direction, a first nanosheet extending in the first direction and formed in the first region, a second nanosheet extending in the first direction and formed in the second region and formed at the same position as the first nanosheet in the first direction, a first gate wiring extending in the second direction and surrounding the periphery of the first nanosheet in the second and third directions, and a second gate wiring extending in the second direction and surrounding the periphery of the second nanosheet in the second and third directions. The second standard cell includes a third nanosheet extending in the first direction and formed at the same position as the first nanosheet in the first direction and formed adjacent to the first nanosheet in the second direction, and a first dummy gate wiring extending in the second direction and surrounding the periphery of the third nanosheet in the second and third directions. The first nanosheet has a first side surface, which is one side in the second direction, exposed from the first gate wiring. The second nanosheet has a second side surface, which is one side in the second direction, exposed from the second gate wiring. The first and third nanosheets have opposing sides exposed from the first gate wiring and the first dummy gate wiring, respectively, or the first and third nanosheets have opposing sides not exposed from the first gate wiring and the first dummy gate wiring, respectively.
[0013] According to this embodiment, the second standard cell having no logic function is arranged in one of the cell rows at both ends in the second direction in a plurality of cell rows including a cell row including a first standard cell having a logic function. The first standard cell includes a first nanosheet, a second nanosheet formed at the same position as the first nanosheet in the first direction, and first and second gate wirings surrounding the peripheries of the first and second nanosheets, respectively. The second standard cell includes a third nanosheet formed at the same position as the first nanosheet in the first direction, and a first dummy gate wiring surrounding the periphery of the third nanosheet. The first nanosheet has a first side surface, which is one side in the second direction, exposed from the first gate wiring. The second nanosheet has a second side surface, which is one side in the second direction, exposed from the second gate wiring. The first and third nanosheets have mutually opposing surfaces exposed from the first gate wiring and the first dummy gate wiring, respectively, or the first and third nanosheets have mutually opposing surfaces not exposed from the first gate wiring and the first dummy gate wiring, respectively. That is, when the surface of the third nanosheet facing the first nanosheet is not surrounded by the first gate wiring, the surface of the third nanosheet facing the first nanosheet is not surrounded by the first dummy gate wiring, whereas when the surface of the first nanosheet facing the first nanosheet is surrounded by the first gate wiring, the surface of the third nanosheet facing the first nanosheet is surrounded by the first dummy gate wiring. This makes it possible to suppress manufacturing variations in semiconductor integrated circuit devices, improve yields, and improve reliability. Effect of the Invention
[0014] According to the present disclosure, it is possible to suppress manufacturing variations, improve yields, and improve reliability of semiconductor integrated circuit devices including termination cells using fork sheet transistors. [Brief description of the drawings]
[0015] [Figure 1] FIG. 1 is a plan view showing an example of a layout structure of a circuit block using standard cells. [Diagram 2] FIG. 2 is a plan view showing a layout structure of a logic cell. [Diagram 3] FIG. 2 is a cross-sectional view showing a layout structure of a logic cell. [Figure 4] FIG. 1 is a plan view showing a specific example of a layout structure of a logic cell. [Diagram 5] FIG. 1 is a cross-sectional view showing a specific example of a layout structure of a logic cell. [Figure 6] A schematic diagram of a circuit configured into a logic cell. [Figure 7] 1 is a plan view showing a layout structure of a semiconductor integrated circuit device according to a first embodiment. [Figure 8] FIG. 2 is a cross-sectional view showing a layout structure of a termination cell according to the first embodiment. [Figure 9] FIG. 13 is a diagram showing a layout structure of a logic cell according to a modification of the first embodiment. [Figure 10] FIG. 13 is a diagram showing a layout structure of a termination cell according to a modification of the first embodiment. [Figure 11] FIG. 11 is a plan view showing a layout structure of a semiconductor integrated circuit device according to a second embodiment. [Figure 12] FIG. 11 is a cross-sectional view showing a layout structure of a termination cell according to a second embodiment. [Figure 13] 13A to 13C are plan views showing variations of the layout structure of a termination cell according to the second embodiment. [Figure 14] 13A to 13C are plan views showing variations of the layout structure of a termination cell according to the second embodiment. [Figure 15] A diagram showing the basic structure of a fork seat FET. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] Hereinafter, the embodiments will be described with reference to the drawings. In the following embodiments, a semiconductor integrated circuit device includes a plurality of standard cells (in this specification, simply referred to as cells as appropriate), and at least some of the plurality of standard cells include fork sheet transistors with a fork-shaped gate electrode among nanosheet FETs (nanowire FETs). A nanosheet FET is a FET using a thin sheet (nanosheet) through which a current flows. The nanosheet is formed of, for example, silicon. In the semiconductor integrated circuit device, some of the nanosheet FETs are fork sheet FETs with a fork-shaped gate electrode.
[0017] In addition, in the present disclosure, the semiconductor layer portions formed on both ends of the nanosheet and constituting the terminals serving as the source or drain of the nanosheet FET are referred to as "pads." In addition, in the following description, in plan views such as Fig. 1, the horizontal direction of the drawing is the X direction (corresponding to the first direction), the vertical direction of the drawing is the Y direction (corresponding to the second direction), and the direction perpendicular to the substrate surface is the Z direction (corresponding to the third direction).
[0018] (Fork seat structure) 15 shows the basic structure of a fork-sheet FET, where (a) is a plan view and (b) is a cross-sectional view taken along line Y-Y' in (a). In the basic structure of FIG. 15, two transistors TR1 and TR2 are arranged side by side with a gap S therebetween in the Y direction. A gate wiring 531 serving as the gate of transistor TR1 and a gate wiring 532 serving as the gate of transistor TR2 both extend in the Y direction and are arranged at the same position in the X direction.
[0019] A channel portion 521 that becomes the channel region of the transistor TR1 and a channel portion 526 that becomes the channel region of the transistor TR2 are composed of nanosheets. In FIG. 15, the channel portions 521 and 526 are each composed of a nanosheet having a three-sheet structure that overlaps in a plan view. Pads 522a and 522b that become the source region or drain region of the transistor TR1 are formed on both sides of the channel portion 521 in the X direction. Pads 527a and 527b that become the source region or drain region of the transistor TR2 are formed on both sides of the channel portion 526 in the X direction. The pads 522a and 522b are formed by epitaxial growth from the nanosheet that constitutes the channel portion 521. The pads 527a and 527b are formed by epitaxial growth from the nanosheet that constitutes the channel portion 526.
[0020] The gate wiring 531 surrounds the outer periphery in the Y direction and Z direction of the channel section 521 made of the nanosheet via a gate insulating film (not shown). However, the surface of the nanosheet constituting the channel section 521 on the side of the transistor TR2 in the Y direction is not covered by the gate wiring 531 and is exposed from the gate wiring 531. That is, in the cross-sectional view of FIG. 15(b), the gate wiring 531 does not cover the right side of the nanosheet constituting the channel section 521 in the drawing, but covers the upper side, left side, and lower side in the drawing. The gate wiring 531 overlaps the nanosheet constituting the channel section 521 on the opposite side of the transistor TR2 in the Y direction by a length OL.
[0021] The gate wiring 532 surrounds the outer periphery in the Y direction and Z direction of the channel part 526 made of the nanosheet via a gate insulating film (not shown). However, the surface of the nanosheet constituting the channel part 526 on the side of the transistor TR1 in the Y direction is not covered by the gate wiring 532 and is exposed from the gate wiring 532. That is, in the cross-sectional view of FIG. 15(b), the gate wiring 532 does not cover the left side of the nanosheet constituting the channel part 526 in the drawing, but covers the upper side, right side, and lower side in the drawing. The gate wiring 532 overlaps the nanosheet constituting the channel part 526 on the opposite side of the transistor TR1 in the Y direction by a length OL.
[0022] If the width (size in the Y direction) of each nanosheet is W and its height (size in the Z direction) is H, then the effective gate width Weff is Weff=2×W+H Since the channel portions 521 and 526 of the transistors TR1 and TR2 are formed of three nanosheets, the effective gate widths of the transistors TR1 and TR2 are 3×(2×W+H) It becomes.
[0023] 15, the gate wiring 531 does not overlap the nanosheet constituting the channel portion 521 on the side of the transistor TR2 in the Y direction. Also, the gate wiring 532 does not overlap the nanosheet constituting the channel portion 526 on the side of the transistor TR1 in the Y direction. This allows the transistors TR1 and TR2 to be closer to each other, thereby realizing a smaller area.
[0024] The number of nanosheets constituting the channel part of the transistor is not limited to three. That is, the nanosheet may be composed of one sheet structure, or may be composed of multiple sheets overlapping in a plan view. In addition, in FIG. 15(b), the cross-sectional shape of the nanosheet is illustrated as a rectangle, but is not limited thereto, and the cross-sectional shape of the nanosheet may be, for example, a square, a circle, an ellipse, or the like.
[0025] Furthermore, a semiconductor integrated circuit device may contain a mixture of fork-sheet FETs and nanosheet FETs in which the gate wiring surrounds the entire periphery of the nanosheet.
[0026] In this specification, "VDD" and "VSS" refer to the power supply voltage or the power supply itself. In addition, in this specification, expressions such as "same wiring width" that mean the width is the same, include the range of manufacturing variations.
[0027] In addition, in the plan views and cross-sectional views of the following embodiments, the description of each insulating film may be omitted. In addition, in the plan views and cross-sectional views of the following embodiments, the nanosheet and the pads on both sides thereof may be depicted in a simplified linear shape. In addition, in this specification, expressions such as "same size" that mean that the size is the same, include the range of manufacturing variations.
[0028] In addition, in this specification, the source and drain of a transistor are appropriately referred to as a "node" of the transistor. In other words, one node of a transistor refers to the source or drain of the transistor, and both nodes of a transistor refer to the source and drain of the transistor.
[0029] In addition, in the following embodiments and their modified examples, the same components and the like are denoted by the same reference numerals and descriptions thereof may be omitted.
[0030] (Circuit block configuration) Fig. 1 is a plan view showing the layout structure of a circuit block using standard cells. In Fig. 1, only the power supply wiring arranged in the standard cells is shown, and the rest is omitted. In addition, the solid lines shown surrounding the cells in the plan views of Fig. 1 and the like indicate the cell frames (the outer edges of inverter cells C2 and the like).
[0031] In the layout of Figure 1, multiple cells lined up in the X direction make up a cell column CR. Multiple cell columns CR (six columns in Figure 1) are arranged in the Y direction. Power supply wiring is formed on both ends of each cell in the Y direction, and each cell receives power supply potentials VDD and VSS from the outside via this power supply wiring. In addition, the entire cell is arranged inverted in the Y direction for each cell column so that the power supply wiring that supplies the power supply potentials VDD and VSS is inverted in the Y direction for each cell column.
[0032] The multiple cells in FIG. 1 include cells having a logic function (eg, inverter cell C2, etc.) and terminal cells not having a logic function (eg, terminal cell C11, etc.).
[0033] In this disclosure, a cell having a logic function such as a NAND gate or a NOR gate within the cell, such as the inverter cell C2, is referred to as a "logic cell" as appropriate.
[0034] In addition, in this disclosure, a "terminal cell" refers to a cell that does not contribute to the logical function of a circuit block and is arranged at the end of the circuit block. Here, the "end of the circuit block" refers to both ends of the cell row constituting the circuit block (here, both ends in the X direction), as well as the top and bottom rows of the circuit block (here, both ends of the cell row in the Y direction). In other words, the "terminal cell" is arranged at both ends of the cell row in the X direction or both ends of the cell row in the Y direction, which are the ends of the circuit block. By arranging the terminal cell, it is possible to suppress the variation in the finished shape of the layout pattern of the cells located inside the terminal cell, and it is possible to suppress the manufacturing variation of the semiconductor integrated circuit device, improve the yield, and improve the reliability.
[0035] In addition, in the present disclosure, a dummy gate wiring is arranged in the termination cell. Here, the term "dummy gate wiring" refers to a gate wiring that does not form a transistor and a gate wiring that forms a transistor that does not contribute to the logical function of the circuit.
[0036] In the present disclosure, an exposed portion may be formed on the outer periphery of a nanosheet arranged in a standard cell. Here, the "exposed portion" refers to a portion of the nanosheet that is not surrounded by the gate wiring (including the dummy gate wiring) on the outer periphery in the Y and Z directions and is exposed from the gate wiring (a portion not covered by the gate wiring).
[0037] In the layout of Fig. 1, a logic unit LC is configured in the center of the circuit block (specifically, inside the thick solid line in Fig. 1). The logic unit LC includes logic cells having logic functions, and realizes the circuit functions of the circuit block. A termination cell unit is formed along the outer edge of the circuit block so as to surround this logic unit LC.
[0038] In Fig. 1, an inverter cell C2 is arranged in the logic section LC, and terminating cells C11, C11a-C11c, C21, C21a-C21c are arranged in the terminating cell section. The terminating cells C11a, C11b, and C11c are arranged by inverting the terminating cell C11 in the Y direction, the X direction, the X direction, and the Y direction, respectively. The terminating cell C21a is arranged by inverting the terminating cell C21 in the Y direction.
[0039] In the topmost cell row CRT of the circuit block, a terminal cell C11a is arranged at the left end of the drawing, a terminal cell C11c is arranged at the right end of the drawing, and a plurality of terminal cells C21 are arranged side by side in the X direction between the terminal cells C11a and C11c. In the bottommost cell row CRB of the circuit block, a terminal cell C11 is arranged at the left end of the drawing, a terminal cell C11b is arranged at the right end of the drawing, and a plurality of terminal cells C21a are arranged side by side in the X direction between the terminal cells C11 and C11b.
[0040] Between the cell strings CRT and CRB, a cell string CRC is arranged. In the cell string CRC, cell strings CRC in which terminal cells C11 and C11b are arranged at the left and right ends of the drawing, respectively, and cell strings CRC in which terminal cells C11a and C11c are arranged at the left and right ends of the drawing, respectively, are arranged alternately in the Y direction.
[0041] Therefore, in Figure 1, termination cells having a similar configuration to termination cell C11 are arranged along the left and right edges of the logic unit LC, and termination cells having a similar configuration to termination cell C21 are arranged along the top and bottom edges of the logic unit LC.
[0042] (Logic cell layout structure) Fig. 2 is a plan view showing the layout structure of the logic cell, and Fig. 3 is a cross-sectional view showing the layout structure of the logic cell. Specifically, Fig. 3 shows a cross-sectional view taken along line Y1-Y1' in Fig. 2.
[0043] As shown in FIG. 2, in the standard cell C1, an N-well region 1 extending in the X direction from the center to the upper side of the drawing, and a P-substrate region 2 extending in the X direction from the center to the lower side of the drawing are formed.
[0044] In addition, power supply wiring 11, 12 extending in the X direction are formed on both ends in the Y direction. Both power supply wiring 11, 12 are buried power supply wiring (BPR: Buried Power Rail) formed in a buried wiring layer. The power supply wiring 11 is formed in the N-well region 1 and supplies a power supply voltage VDD. The power supply wiring 12 is formed in the P-substrate region 2 and supplies a power supply voltage VSS.
[0045] In the standard cell C1, nanosheets 21a to 24a and 21b to 24b extending in the X and Y directions are formed. Nanosheets 21a and 21b are formed side by side in the X direction. Nanosheets 22a and 22b are formed side by side in the X direction. Nanosheets 23a and 23b are formed side by side in the X direction. Nanosheets 24a and 24b are formed side by side in the X direction.
[0046] The nanosheets 21a and 22a overlap with the gate wiring 41 in a planar view. The nanosheets 21b and 22b overlap with the gate wiring 42 in a planar view. The nanosheets 23a and 24a overlap with the gate wiring 43 in a planar view. The nanosheets 23b and 24b overlap with the gate wiring 44 in a planar view.
[0047] The nanosheets 21a, 21b, 22a, and 22b form the channel portions of the transistors P1 to P4, respectively. The nanosheets 23a, 23b, 24a, and 24b form the channel portions of the transistors N1 to N4, respectively.
[0048] Pads 31a to 31c, 32a to 32c doped with P-type semiconductor are respectively formed on the left side of nanosheet 21a in the figure, between nanosheets 21a and 21b, on the right side of nanosheet 21b in the figure, on the left side of nanosheet 22a in the figure, between nanosheets 22a and 22b, and on the right side of nanosheet 22b in the figure.
[0049] Pads 33a to 33c, 34a to 34c doped with N-type semiconductor are respectively formed on the left side of nanosheet 23a in the figure, between nanosheets 23a and 23b, on the right side of nanosheet 23b in the figure, on the left side of nanosheet 24a in the figure, between nanosheets 24a and 24b, and on the right side of nanosheet 24b in the figure.
[0050] Pads 31a and 31b form the node of transistor P1. Pads 31b and 31c form the node of transistor P2. Pads 32a and 32b form the node of transistor P3. Pads 32b and 32c form the node of transistor P4. Pads 33a and 33b form the node of transistor N1. Pads 33b and 33c form the node of transistor N2. Pads 34a and 34b form the node of transistor N3. Pads 34b and 34c form the node of transistor N4.
[0051] In the standard cell C1, gate wirings 41 to 44 and dummy gate wirings 45 to 48 extending in the Y and Z directions are formed. Specifically, the dummy gate wiring 45, the gate wirings 41, 42 and the dummy gate wiring 46 are formed to be aligned at an equal pitch in the X direction. The dummy gate wiring 47, the gate wirings 43, 44 and the dummy gate wiring 48 are formed to be aligned at an equal pitch in the X direction. The dummy gate wirings 45, 47 are formed at the left end of the standard cell C1 in the drawing. The dummy gate wirings 46, 48 are formed at the right end of the standard cell C1 in the drawing.
[0052] Gate wiring 41 serves as the gates of transistors P1 and P3, gate wiring 42 serves as the gates of transistors P2 and P4, gate wiring 43 serves as the gates of transistors N1 and N3, and gate wiring 44 serves as the gates of transistors N2 and N4.
[0053] That is, the transistor P1 is composed of the nanosheet 21a, the pads 31a and 31b, and the gate wiring 41. The transistor P2 is composed of the nanosheet 21b, the pads 31b and 31c, and the gate wiring 42. The transistor P3 is composed of the nanosheet 22a, the pads 32a and 32b, and the gate wiring 41. The transistor P4 is composed of the nanosheet 22b, the pads 32b and 32c, and the gate wiring 42. The transistor N1 is composed of the nanosheet 23a, the pads 33a and 33b, and the gate wiring 43. The transistor N2 is composed of the nanosheet 23b, the pads 33b and 33c, and the gate wiring 44. The transistor N3 is composed of the nanosheet 24a, the pads 34a and 34b, and the gate wiring 43. The transistor N4 is composed of the nanosheet 24b, the pads 34b and 34c, and the gate wiring 44.
[0054] As shown in Fig. 3, the nanosheets 21b to 24b each consist of three sheet-like semiconductors (nanosheets). The nanosheets 21b to 24b are arranged so that the nanosheets constituting each of them overlap in a plan view, and are formed to be spaced apart in the Z direction. Although not shown in the figure, the nanosheets 21a to 24a also consist of three sheet-like semiconductor layers, similar to the nanosheets 21b to 24b. That is, the transistors P1 to P4 and N1 to N4 each include three nanosheets.
[0055] 3, exposed portions (portions not surrounded by gate wiring) are formed on the outer periphery of each of nanosheets 21b to 24b in the Y and Z directions. Specifically, the side surface of nanosheet 21b on the left side of the drawing is not covered by gate wiring 42, and the side surface of nanosheet 22b on the right side of the drawing is not covered by gate wiring 42. The side surface of nanosheet 23b on the left side of the drawing is not covered by gate wiring 44, and the side surface of nanosheet 24b on the right side of the drawing is not covered by gate wiring 44.
[0056] That is, nanosheets 21b and 23b have exposed portions formed on the left side of the drawing (upper side in FIG. 2). Nanosheets 22b and 24b have exposed portions formed on the right side of the drawing (lower side in FIG. 2). Similarly, in FIG. 2, nanosheets 21a and 23a have exposed portions formed on the upper side of the drawing. Nanosheets 22a and 24a have exposed portions formed on the lower side of the drawing.
[0057] Therefore, the surfaces of the nanosheets 21a, 21b, 23a, and 23b on the same side (the upper surfaces in FIG. 2) are exposed from the gate wiring. The surfaces of the nanosheets 22a, 22b, 24a, and 24b on the same side (the lower surfaces in FIG. 2) are exposed from the gate wiring.
[0058] In addition, the upper ends of nanosheets 21a and 21b in the drawing are aligned in the Y direction. The lower ends of nanosheets 22a and 22b in the drawing are aligned in the Y direction. The upper ends of nanosheets 23a and 23b in the drawing are aligned in the Y direction. The lower ends of nanosheets 24a and 24b in the drawing are aligned in the Y direction.
[0059] The upper and lower ends of the gate wirings 41 and 42 and the dummy gate wirings 45 and 46 are aligned in the Y direction. The upper and lower ends of the gate wirings 43 and 44 and the dummy gate wirings 47 and 48 are aligned in the Y direction.
[0060] (Example of a logic cell) Fig. 4 is a plan view showing a specific example of the layout structure of a logic cell, Fig. 5 is a cross-sectional view showing a specific example of the layout structure of a logic cell, and Fig. 6 is a circuit diagram configured in the logic cell. Specifically, Fig. 4(a) shows the layout structure of an inverter cell C2, and Fig. 4(b) shows the layout structure of a NAND cell C3. Fig. 5(a) shows a cross-sectional view of Y2-Y2' in Fig. 4(a), and Fig. 5(b) shows a cross-sectional view of Y3-Y3' in Fig. 4(a). Fig. 6(a) is a circuit diagram configured in the inverter cell C2 shown in Fig. 4(a), and Fig. 6(b) is a circuit diagram configured in the NAND cell C3 shown in Fig. 4(b).
[0061] First, the layout structure of the inverter cell C2 will be described.
[0062] As shown in Fig. 6(a), the inverter cell C2 has transistors P11 and N11, and an inverter circuit with an input A1 and an output Y1 is configured. The transistors P11 and N11 are each composed of two transistors, but are not shown in Fig. 6(a). The transistors P1 and P3 correspond to the transistor P11, and the transistors N1 and N3 correspond to the transistor N11. The wirings 71 and 72 correspond to the input A1 and the output Y1, respectively.
[0063] As shown in FIG. 4(a) and FIGS. 5(a) and 5(b), the inverter cell C2 has a smaller cell width (cell size in the X direction) than the standard cell C1, and does not include the transistors P2, P4, N2, and N4.
[0064] Specifically, the inverter cell C2 does not include the nanosheets 21b to 24b, the pads 31c to 34c, and the gate wirings 42 and 44. In addition, the gate wirings 41 and 43 are connected via a gate connection portion 49.
[0065] Local wirings 51 to 53 extending in the Y direction are formed on the upper layer of the pads 31a to 34a and 31b to 34b. The local wiring 51 is connected to the pads 31a and 32a. The local wiring 52 is connected to the pads 31b to 34b. The local wiring 53 is connected to the pads 33a and 34a.
[0066] The local wiring 51 is connected to the power supply wiring 11 via a contact 61. The local wiring 53 is connected to the power supply wiring 12 via a contact 62.
[0067] Wires 71 and 72 extending in the X direction are formed in a first metal wiring layer above the local wires 51 to 53. The wire 71 is connected to the gate connection portion 49 via a contact 81. The wire 72 is connected to the local wire 52 via a contact 82.
[0068] Next, the layout structure of the NAND cell C3 will be described.
[0069] As shown in FIG. 6(b), the NAND cell C3 has transistors P21, P22, N21, and N22, and is configured as a two-input NAND circuit with inputs A2 and B2 and output Y2. The transistors P21, P22, N21, and N22 are each configured with two transistors, but are not shown in FIG. 6(a). The transistors P1 and P3 correspond to the transistor P21, the transistors P2 and P4 correspond to the transistor P22, the transistors N1 and N3 correspond to the transistor N21, and the transistors N2 and N4 correspond to the transistor N22. The wirings 73 to 75 correspond to the output Y2 and the inputs B2 and A2, respectively.
[0070] As shown in FIG. 4B, in the NAND cell C3, the gate wirings 41 and 43 are connected via a gate connection portion 49, and the gate wirings 42 and 44 are connected via a gate connection portion 50.
[0071] Local wirings 54 to 58 extending in the Y direction are formed on the upper layer of the pads 31a to 34a, 31b to 34b, and 31c to 34c. The local wiring 54 is connected to the pads 31a and 32a. The local wiring 55 is connected to the pads 31b and 32b. The local wiring 56 is connected to the pads 31c to 34c. The local wiring 57 is connected to the pads 33a and 34a. The local wiring 58 is connected to the pads 33b and 34b.
[0072] The local wiring 55 is connected to the power supply wiring 11 via a contact 63. The local wiring 57 is connected to the power supply wiring 12 via a contact 64.
[0073] Wires 73-75 extending in the X-direction are formed in a first metal wiring layer above the local wires 54-58. Wire 73 is connected to local wire 54 via a contact 83, and is connected to local wire 56 via a contact 84. Wire 74 is connected to gate connection portion 49 via a contact 85. Wire 75 is connected to gate connection portion 50 via a contact 86.
[0074] (First embodiment) Fig. 7 is a plan view showing the layout structure of the semiconductor integrated circuit device according to the first embodiment, and Fig. 8 is a cross-sectional view showing the layout structure of the semiconductor integrated circuit device according to the first embodiment. Specifically, Fig. 7 is an enlarged view of a W1 portion in Fig. 1. Fig. 8(a) shows a cross-sectional view along Y4-Y4' in Fig. 7, and Fig. 8(b) shows a cross-sectional view along Y5-Y5' in Fig. 7.
[0075] As shown in FIGS. 1 and 7, the terminal cell C11 is disposed at the left end of the cell row CR in the drawing, adjacent to the left side of the inverter cell C2 in the drawing.
[0076] Specifically, in the terminal cell C11, an N-well region 101 extending in the X direction from the center to the upper side of the drawing is formed, and a P-substrate region 102 extending in the X direction from the center to the lower side of the drawing is formed.
[0077] In addition, power supply wiring 111, 112 extending in the X direction are formed on both ends in the Y direction. Both power supply wiring 111, 112 are buried power supply wiring (BPR) formed in a buried wiring layer. The power supply wiring 111 is formed in the N-well region 101, and supplies a power supply voltage VDD. The power supply wiring 112 is formed in the P-substrate region 102, and supplies a power supply voltage VSS.
[0078] In the terminal cell C11, nanosheets 121a to 124a extending in the X and Y directions are formed.
[0079] The nanosheets 121a and 122a overlap, in a plan view, with the dummy gate wiring 143. The nanosheets 123a and 124a overlap, in a plan view, with the dummy gate wiring 146. The nanosheets 121a to 124a form the channels of the dummy transistors DP11, DP12, DN11, and DN12, respectively.
[0080] Dummy pads 131a, 131b, 132a, and 132b doped with a P-type semiconductor are formed on the left side of nanosheet 121a in the figure, the right side of nanosheet 121a in the figure, the left side of nanosheet 122a in the figure, and the right side of nanosheet 122a in the figure, respectively.
[0081] Dummy pads 133a, 133b, 134a, and 134b doped with N-type semiconductor are formed on the left side of nanosheet 123a in the figure, the right side of nanosheet 123a in the figure, the left side of nanosheet 124a in the figure, and the right side of nanosheet 124a in the figure, respectively.
[0082] The dummy pads 131a and 131b form a node of the dummy transistor DP11. The dummy pads 132a and 132b form a node of the dummy transistor DP12. The dummy pads 133a and 133b form a node of the dummy transistor DN11. The dummy pads 134a and 134b form a node of the dummy transistor DN12.
[0083] In the terminal cell C11, dummy gate wirings 141 to 146 extending in the Y and Z directions are formed. The dummy gate wirings 141 and 144 are formed at the left end of the terminal cell C11 in the drawing. In addition, the dummy gate wirings 45 and 47 are formed at the cell boundary between the terminal cell C11 and the inverter cell C2. The dummy gate wiring 143 serves as the gates of the dummy transistors DP11 and DP12, and the dummy gate wiring 146 serves as the gates of the dummy transistors DN11 and DN12.
[0084] Local wirings 151 to 154 extending in the Y direction are formed on the upper layer of the dummy pads 131a to 134a and 131b to 134b. The local wiring 151 is connected to the dummy pads 131a and 132a. The local wiring 152 is connected to the dummy pads 131b and 132b. The local wiring 153 is connected to the dummy pads 133a and 134a. The local wiring 154 is connected to the dummy pads 133b and 134b.
[0085] 8(a), exposed portions (portions not surrounded by dummy gate wiring) are formed on the outer peripheries of nanosheets 121a to 124a in the Y and Z directions. Specifically, the side surface of nanosheet 121a on the left side of the drawing is not covered by dummy gate wiring 143, and the side surface of nanosheet 122a on the right side of the drawing is not covered by dummy gate wiring 143. The side surface of nanosheet 123a on the left side of the drawing is not covered by dummy gate wiring 146, and the side surface of nanosheet 124a on the right side of the drawing is not covered by dummy gate wiring 146.
[0086] That is, nanosheets 121a and 123a each have an exposed portion formed on the left side of the drawing (upper side in FIG. 7), and nanosheets 122a and 124a each have an exposed portion formed on the right side of the drawing (lower side in FIG. 7).
[0087] Therefore, the surface of nanosheet 121a on the same side as nanosheet 21a of inverter cell C2 (the upper surface in FIG. 7) is exposed from dummy gate wiring 143. The surface of nanosheet 122a on the same side as nanosheet 22a of inverter cell C2 (the lower surface in FIG. 7) is exposed from dummy gate wiring 143. The surface of nanosheet 123a on the same side as nanosheet 23a of inverter cell C2 (the upper surface in FIG. 7) is exposed from dummy gate wiring 146. The surface of nanosheet 124a on the same side as nanosheet 24a of inverter cell C2 (the lower surface in FIG. 7) is exposed from dummy gate wiring 146.
[0088] In addition, in FIG. 7, the nanosheets 121a to 124a are formed in the same layer as the nanosheets 21a to 24a.
[0089] Furthermore, nanosheet 121a is formed at the same position in the Y direction as nanosheet 21a. Nanosheet 122a is formed at the same position in the Y direction as nanosheet 22a. Nanosheet 123a is formed at the same position in the Y direction as nanosheet 23a. Nanosheet 124a is formed at the same position in the Y direction as nanosheet 24a.
[0090] In addition, the upper end of nanosheet 121a in the drawing is aligned with the upper end of nanosheet 21a in the Y direction. The lower end of nanosheet 122a in the drawing is aligned with the lower end of nanosheet 22a in the Y direction. The upper end of nanosheet 123a in the drawing is aligned with the upper end of nanosheet 23a in the Y direction. The lower end of nanosheet 124a in the drawing is aligned with the lower end of nanosheet 24a in the Y direction.
[0091] The dummy pads 131a to 134a and 131b to 134b are formed in the same layer as the pads 31a to 34a and 31b to 34b.
[0092] Moreover, the dummy pads 131a and 131b are formed at the same position in the Y direction as the pads 31a and 31b. The dummy pads 132a and 132b are formed at the same position in the Y direction as the pads 32a and 32b. The dummy pads 133a and 133b are formed at the same position in the Y direction as the pads 33a and 33b. The dummy pads 134a and 134b are formed at the same position in the Y direction as the pads 34a and 34b.
[0093] The dummy pads 131a, 131b and the pads 31a, 31b are arranged at equal pitches in the X direction. The dummy pads 132a, 132b and the pads 32a, 32b are arranged at equal pitches in the X direction. The dummy pads 133a, 133b and the pads 33a, 33b are arranged at equal pitches in the X direction. The dummy pads 134a, 134b and the pads 34a, 34b are arranged at equal pitches in the X direction.
[0094] The dummy gate wirings 141 to 146 are formed in the same layer as the gate wirings 41 and 43 and the dummy gate wirings 45 to .
[0095] The dummy gate wirings 141 to 143 are formed at the same position in the Y direction as the gate wiring 41 and the dummy gate wirings 45 and 46. The dummy gate wirings 144 to 146 are formed at the same position in the Y direction as the gate wiring 43 and the dummy gate wirings 47 and 48.
[0096] The dummy gate wirings 141 to 143, 45, the gate wiring 41, and the dummy gate wiring 46 are arranged at equal pitches in the X direction. The dummy gate wirings 144 to 146, 47, the gate wiring 43, and the dummy gate wiring 48 are arranged at equal pitches in the X direction.
[0097] The upper and lower ends of the dummy gate wirings 141 to 143 are aligned in the Y direction with the upper and lower ends of the gate wiring 41 and the dummy gate wirings 45 and 46. The upper and lower ends of the dummy gate wirings 144 to 146 are aligned in the Y direction with the upper and lower ends of the gate wiring 43 and the dummy gate wirings 47 and 48.
[0098] The local wirings 151-154 are formed in the same layer as the local wirings 51-53.
[0099] The local wirings 151, 152, 51 and 52 are arranged at equal pitches in the X direction. The local wirings 153, 154, 53 and 52 are arranged at equal pitches in the X direction.
[0100] With the above configuration, the semiconductor integrated circuit device includes a plurality of cell rows CR each including a plurality of standard cells arranged in the X direction. The cell row CR includes an inverter cell C2 having a logic function and a terminal cell C11 arranged at the left end of the cell row CR in the drawing. The terminal cell C11 is arranged adjacent to the left side of the inverter cell C2 at the left end of the cell row CR in the drawing. The inverter cell C2 includes an N-well region 1 which is a region for forming a P-type transistor, a P-substrate region 2 which is a region for forming an N-type transistor, a nanosheet 22a extending in the X direction and formed in the N-well region 1, a nanosheet 23a extending in the X direction and formed in the P-substrate region 2, a gate wiring 41 extending in the Y direction and surrounding the outer periphery of the nanosheet 22a in the Y direction and the Z direction, and a gate wiring 43 extending in the Y direction and surrounding the outer periphery of the nanosheet 23a in the Y direction and the Z direction. The terminal cell C11 includes a nanosheet 122a extending in the X direction and formed at the same position as the nanosheet 22a in the Y direction, a nanosheet 123a extending in the X direction and formed at the same position as the nanosheet 23a in the Y direction, a dummy gate wiring 143 extending in the Y direction and surrounding the outer periphery of the nanosheet 122a in the Y direction and the Z direction, and a dummy gate wiring 146 extending in the Y direction and surrounding the outer periphery of the nanosheet 123a in the Y direction and the Z direction. The nanosheet 22a has a lower surface exposed from the gate wiring 41, and the nanosheet 23a has an upper surface exposed from the gate wiring 43. The nanosheet 122a has a lower surface exposed from the dummy gate wiring 143, and the nanosheet 123a has an upper surface exposed from the dummy gate wiring 146.
[0101] That is, nanosheets 22a and 122a arranged at the same position in the Y direction have the same surfaces in the Y direction exposed from gate wiring 41 and dummy gate wiring 143. Nanosheets 23a and 123a arranged at the same position in the Y direction have the same surfaces in the Y direction exposed from gate wiring 43 and dummy gate wiring 146. This makes it possible to suppress manufacturing variations in semiconductor integrated circuit devices, improve yields, and improve reliability.
[0102] Furthermore, the surfaces of the nanosheets 22a and 23a that face each other are exposed from the gate wirings 41 and 43, respectively. The surfaces of the nanosheets 122a and 123a that face each other are exposed from the dummy gate wirings 143 and 146, respectively. This eliminates the need for overlapping of the gate wirings, including the dummy gate wirings, between the nanosheets 22a and 23a and between the nanosheets 122a and 123a, thereby making it possible to reduce the area of the semiconductor integrated circuit device.
[0103] Moreover, the inverter cell C2 extends in the X direction and includes nanosheets 21a and 24a formed in the N-well region 1 and the P-substrate region 2, respectively. The terminal cell C11 extends in the X direction and includes nanosheets 121a and 124a formed at the same positions as the nanosheets 21a and 24a in the Y direction, respectively. The gate wirings 41 and 43 and the dummy gate wirings 143 and 146 surround the outer peripheries of the nanosheets 21a, 24a, 121a, and 124a in the Y direction and the Z direction, respectively. The upper surface of the nanosheet 21a is exposed from the gate wiring 41. The lower surface of the nanosheet 24a is exposed from the gate wiring 43. The upper surface of the nanosheet 121a is exposed from the dummy gate wiring 143. The lower surface of the nanosheet 124a is exposed from the dummy gate wiring 146.
[0104] That is, nanosheets 21a and 121a arranged at the same position in the Y direction have the same surfaces in the Y direction exposed from gate wiring 41 and dummy gate wiring 143. Nanosheets 24a and 124a arranged at the same position in the Y direction have the same surfaces in the Y direction exposed from gate wiring 43 and dummy gate wiring 146. This makes it possible to suppress manufacturing variations in semiconductor integrated circuit devices, improve yields, and improve reliability.
[0105] In addition, the upper end of nanosheet 121a in the drawing is aligned with the upper end of nanosheet 21a in the Y direction. The lower end of nanosheet 122a in the drawing is aligned with the lower end of nanosheet 22a in the Y direction. The upper end of nanosheet 123a in the drawing is aligned with the upper end of nanosheet 23a in the Y direction. The lower end of nanosheet 124a in the drawing is aligned with the lower end of nanosheet 24a in the Y direction. This makes it possible to suppress manufacturing variations in semiconductor integrated circuit devices, improve yields, and improve reliability.
[0106] Moreover, the nanosheets 121a to 124a are formed in the same layer as the nanosheets 21a to 24a. The dummy pads 131a to 134a, 131b to 134b are formed in the same layer as the pads 31a to 34a, 31b to 34b. The dummy gate wirings 141 to 146 are formed in the same layer as the gate wirings 41, 43 and the dummy gate wirings 45 to 48. The local wirings 151 to 154 are formed in the same layer as the local wirings 51 to 53. That is, by forming a nanosheet, a dummy pad, a dummy gate wiring, and a local wiring in the terminal cell, the pads including the dummy pads, the gate wiring including the dummy gate wiring, and the local wiring are regularly arranged. This makes it possible to suppress the variation in the finished shape of the layout pattern of the cells arranged inside the terminal cell, and to suppress the manufacturing variation of the semiconductor integrated circuit device, improve the yield, and improve the reliability.
[0107] Moreover, the dummy transistors DP11, DP12, DN11, and DN12 are arranged adjacent to the dummy gate wirings 45 and 47 arranged at the boundary between the inverter cell C2 and the termination cell C11. That is, by providing the termination cell with dummy transistors adjacent to the dummy gate wiring arranged at the boundary between the termination cell and the logic cell, the distance from the cell arranged at the end of the logic section to the nearest transistor can be made constant, thereby improving the performance predictability of the logic section.
[0108] The cell width of the terminal cell C11 may be wider or narrower than the size shown in FIG.
[0109] Furthermore, the termination cell C11 is provided with four dummy transistors, ie, dummy transistors DP11, DP12, DN11, and DN12, but the number of dummy transistors provided in the termination cell C11 is not limited to four.
[0110] Furthermore, in the terminal cell C11, eight dummy gate wirings, ie, the dummy gate wirings 45, 47, and 141 to 146, are formed, but the number of dummy gate wirings provided in the terminal cell C11 is not limited to eight.
[0111] Furthermore, the terminal cell C11 is provided with four local wirings, ie, the local wirings 151 to 154, but the number of local wirings provided in the terminal cell C11 is not limited to four.
[0112] Furthermore, in a logic cell (inverter cell C2 in FIG. 7), three or more nanosheet FETs may be provided for one gate wiring (including a dummy gate wiring). In this case, the nanosheet of the terminal cell is formed at the same position in the Y direction as the nanosheet of the logic cell. Then, when the lower surface of the nanosheet of the logic cell is exposed from the gate wiring, the lower surface of the nanosheet of the terminal cell is exposed from the dummy gate wiring, and when the upper surface of the nanosheet of the logic cell is exposed from the gate wiring, the upper surface of the nanosheet of the terminal cell is exposed from the dummy gate wiring.
[0113] (Modification) Fig. 9 is a diagram showing a layout structure of a logic cell according to a modification of the first embodiment, and Fig. 10 is a diagram showing a layout structure of a termination cell according to a modification of the first embodiment. Specifically, Fig. 9(a) is a plan view showing the layout structure of a standard cell C4, and Fig. 9(b) is a cross-sectional view taken along line Y6-Y6' in Fig. 9(a). Fig. 10(a) is a plan view showing the layout structure of a termination cell C12, and Fig. 10(b) is a cross-sectional view taken along line Y7a-Y7a' in Fig. 10(a), and Fig. 10(c) is a cross-sectional view taken along line Y7b-Y7b' in Fig. 10(a).
[0114] In FIG. 1, when the standard cell C4 is placed in place of the inverter cell C2, the termination cell C12 is placed in place of the termination cell C11.
[0115] In the standard cell C1 (inverter cell C2) and the terminal cell C11, two nanosheet FETs are provided for one gate wiring, but in the standard cell C4 and the terminal cell C12, one nanosheet FET is provided for one gate wiring.
[0116] (About standard cell C4) 9(a), nanosheets 22c, 22d, 23c, and 23d extending in the X and Y directions are formed in the standard cell C4. The nanosheets 22c, 22d, 23c, and 23d overlap the gate wirings 41 to 44 in a plan view. The nanosheets 22c, 22d, 23c, and 23d form the channels of the transistors P5, P6, N5, and N6, respectively.
[0117] Pads 32d to 32f doped with a P-type semiconductor are formed on the left side of the nanosheet 22c in the figure, between the nanosheets 22c and 22d, and on the right side of the nanosheet 22d in the figure, respectively.
[0118] Pads 33d to 33f doped with an N-type semiconductor are formed on the left side of the nanosheet 23c in the figure, between the nanosheets 23c and 23d, and on the right side of the nanosheet 23d in the figure, respectively.
[0119] The pads 32d and 32e form a node of the transistor P5. The pads 32e and 32f form a node of the transistor P6. The pads 33d and 33e form a node of the transistor N5. The pads 33e and 33f form a node of the transistor N6.
[0120] Gate wiring 41 serves as the gate of transistor P5, gate wiring 42 serves as the gate of transistor P6, gate wiring 43 serves as the gate of transistor N5, and gate wiring 44 serves as the gate of transistor N6.
[0121] As shown in Figures 9(a) and (b), exposed portions are formed on the outer peripheries of nanosheets 22c, 22d, 23c, and 23d in the Y and Z directions, respectively. Specifically, in Figure 9(a), exposed portions are formed on the lower side of nanosheets 22c and 22d in the drawing. Exposed portions are formed on the upper side of nanosheets 23c and 23d in the drawing. That is, in standard cell C4, the surfaces of nanosheets 22c and 22d on the same side (the upper surface in Figure 9(a)) are exposed from the gate wiring. The surfaces of nanosheets 23c and 23d on the same side (the lower surface in Figure 9(a)) are exposed from the gate wiring.
[0122] 9(a), the upper surfaces of nanosheets 22c and 22d are covered by gate wirings 41 and 42, respectively, and the lower surfaces of nanosheets 23c and 23d are covered by gate wirings 43 and 44, respectively. That is, the upper surfaces of nanosheets 22c and 22d are not exposed from the gate wiring, and the lower surfaces of nanosheets 23c and 23d are not exposed from the gate wiring.
[0123] Based on the layout structure of the standard cell C4, a standard cell that realizes a logic function is formed by forming vias and wiring (local wiring, metal wiring) for connecting transistors. In the following description, the standard cell C4 in which a logic function is realized by forming vias and wiring may be referred to as a standard cell C4 having a logic function.
[0124] (Regarding the terminal cell C12) 10(a), nanosheets 122c and 123c extending in the X and Y directions are formed in the terminal cell C12. The nanosheets 122c and 123c overlap with the dummy gate wirings 143 and 146, respectively, in a plan view. The nanosheets 122c and 123c form the channels of the dummy transistors DP13 and DN13, respectively.
[0125] Dummy pads 132c, 132d doped with a P-type semiconductor are formed on the left and right sides of the nanosheet 122c in the figure, respectively.
[0126] Dummy pads 133c and 133d doped with an N-type semiconductor are formed on the left and right sides of the nanosheet 123c in the figure, respectively.
[0127] The dummy pads 132c and 132d form a node of the dummy transistor DP13. The dummy pads 133c and 133d form a node of the dummy transistor DN13.
[0128] The dummy gate wiring 143 serves as the gate of the dummy transistor DP13, and the dummy gate wiring 146 serves as the gate of the dummy transistor DN13.
[0129] Furthermore, local wirings 155 to 158 extending in the Y direction are formed on the upper layer of the dummy pads 132c, 132d, 133c, and 133d. The local wirings 155 to 158 are connected to the dummy pads 132c, 132d, 133c, and 133d, respectively.
[0130] As shown in FIGS. 10(a) to 10(c), exposed portions are formed on the outer peripheries of the nanosheets 122c and 123c in the Y and Z directions, respectively. Specifically, in FIG. 10(a), the exposed portion is formed on the lower side of the nanosheet 122c in the drawing. The exposed portion is formed on the upper side of the nanosheet 123c in the drawing. That is, in the terminal cell C12, the surface of the nanosheet 122c on the same side as the nanosheets 22c and 22d of the standard cell C4 having a logic function (the lower surface in FIG. 10(a)) is exposed from the dummy gate wiring 143. The surface of the nanosheet 123c on the same side as the nanosheets 23c and 23d of the standard cell C4 having a logic function (the upper surface in FIG. 10(a)) is exposed from the dummy gate wiring 146.
[0131] In FIG. 1, when a standard cell C4 having a logic function is arranged in place of the inverter cell C2, a terminal cell C12 is arranged in place of the terminal cell C11, and thereby the same effect as that of the terminal cell C11 can be obtained.
[0132] In addition, in FIG. 10(a), the nanosheet 122c has an upper side covered with a dummy gate wiring 143. The nanosheet 123c has a lower side covered with a dummy gate wiring 146. That is, the side of the nanosheet 122c on the same side as the nanosheets 22c and 22d (the upper side in FIG. 9(a) and FIG. 10(a)) is not exposed from the dummy gate wiring 143. The side of the nanosheet 123c on the same side as the nanosheets 23c and 23d (the lower side in FIG. 9(a) and FIG. 10(a)) is not exposed from the dummy gate wiring 146. This makes it possible to suppress manufacturing variations in semiconductor integrated circuit devices, improve yields, and improve reliability.
[0133] In the standard cell C4 in FIG. 9(a), the upper surfaces of the nanosheets 22c and 22d are not exposed from the gate wirings 41 and 42, respectively, and the lower surfaces are exposed from the gate wirings 41 and 42, respectively, but this is not limited thereto. The upper surfaces of the nanosheets 22c and 22d may be exposed from the gate wirings 41 and 42, respectively, and the lower surfaces may not be exposed from the gate wirings 41 and 42, respectively. In this case, in the terminal cell C12 in FIG. 10(a), the upper surface of the nanosheet 122c is exposed from the dummy gate wiring 143, and the lower surface is not exposed from the dummy gate wiring 143.
[0134] Further, the upper surfaces of the nanosheets 23c and 23d are exposed from the gate wirings 43 and 44, respectively, and the lower surfaces of the nanosheets 23c and 23d are not exposed from the gate wirings 43 and 44, respectively, but are not limited to this. The upper surfaces of the nanosheets 23c and 23d may not be exposed from the gate wirings 43 and 44, respectively, and the lower surfaces of the nanosheets 23c and 23d may be exposed from the gate wirings 43 and 44, respectively. In this case, in the terminal cell C12 in FIG. 10(a), the upper surface of the nanosheet 123c is not exposed from the dummy gate wiring 146, and the lower surface of the nanosheet 123c is exposed from the dummy gate wiring 146.
[0135] Second embodiment Fig. 11 is a plan view showing the layout structure of the semiconductor integrated circuit device according to the second embodiment, and Fig. 11 is a cross-sectional view showing the layout structure of the semiconductor integrated circuit device according to the second embodiment. Specifically, Fig. 11 is an enlarged view of a portion W2 in Fig. 1. Fig. 12(a) shows a cross-sectional view along Y8-Y8' in Fig. 11, and Fig. 12(b) shows a cross-sectional view along Y9-Y9' in Fig. 11.
[0136] 1 and 11, the terminal cell C21 is arranged in the topmost cell row CRT. The terminal cell C21 is arranged adjacent to the upper side of the inverter cell C2 in the drawing.
[0137] 11, in the terminal cell C21, a P-substrate region 201 extending in the X direction is formed from the center of the cell to the upper side of the drawing. An N-well region 202 extending in the X direction is formed from the center of the cell to the lower side of the drawing.
[0138] In addition, power supply wiring 211, 212 extending in the X direction are formed on both ends in the Y direction. Both power supply wiring 211, 212 are buried power supply wiring (BPR) formed in a buried wiring layer. The power supply wiring 211 is formed in the P substrate region 201 and supplies a power supply voltage VSS. The power supply wiring 212 is formed in the N well region 202 and supplies a power supply voltage VDD.
[0139] In the terminal cell C21, nanosheets 221a to 224a and 221b to 224b extending in the X and Y directions are formed.
[0140] The nanosheets 221a and 222a overlap with the dummy gate wiring 242 in a planar view. The nanosheets 221b and 222b overlap with the dummy gate wiring 243 in a planar view. The nanosheets 223a and 224a overlap with the dummy gate wiring 246 in a planar view. The nanosheets 223b and 224b overlap with the dummy gate wiring 247 in a planar view. The nanosheets 221a, 221b, 222a, and 222b respectively constitute the channel portions of the dummy transistors DN21, DN22, DN23, and DN24. The nanosheets 223a, 223b, 224a, and 224b respectively constitute the channel portions of the dummy transistors DP21, DP22, DP23, and DP24.
[0141] Dummy pads 231a to 231c and 232a to 232c doped with an N-type semiconductor are formed on the left side of the nanosheet 221a in the drawing, between the nanosheets 221a and 221b, on the right side of the nanosheet 221b in the drawing, on the left side of the nanosheet 222a in the drawing, between the nanosheets 222a and 222b, and on the right side of the nanosheet 222b in the drawing. The dummy pads 231a and 231b form the node of the dummy transistor DN21. The dummy pads 231b and 231c form the node of the dummy transistor DN22. The dummy pads 232a and 232b form the node of the dummy transistor DN23. The dummy pads 232b and 232c form the node of the dummy transistor DN24.
[0142] Dummy pads 233a to 233c, 234a to 234c doped with a P-type semiconductor are formed on the left side of the nanosheet 223a in the drawing, between the nanosheets 223a and 223b, on the right side of the nanosheet 223b in the drawing, on the left side of the nanosheet 224a in the drawing, between the nanosheets 224a and 224b, and on the right side of the nanosheet 224b in the drawing. The dummy pads 233a and 233b form the nodes of the dummy transistor DP21. The dummy pads 233b and 233c form the nodes of the dummy transistor DP22. The dummy pads 234a and 234b form the nodes of the dummy transistor DP23. The dummy pads 234b and 234c form the nodes of the dummy transistor DP24.
[0143] In the terminal cell C21, dummy gate wirings 241 to 248 extending in the Y direction and the Z direction are formed. The dummy gate wirings 241 and 245 are formed at the cell boundary between the terminal cell C21 and a cell arranged adjacent to the terminal cell C21 on the left side of the drawing. The dummy gate wirings 244 and 248 are formed at the cell boundary between the terminal cell C21 and a cell arranged adjacent to the terminal cell C21 on the right side of the drawing. The dummy gate wiring 242 serves as the gates of the dummy transistors DN21 and DN23, and the dummy gate wiring 243 serves as the gates of the dummy transistors DN22 and DN24. The dummy gate wiring 246 serves as the gates of the dummy transistors DP21 and DP23, and the dummy gate wiring 247 serves as the gates of the dummy transistors DP22 and DP24.
[0144] Local wirings 251 to 256 extending in the Y direction are formed on the upper layer of the dummy pads 231a to 234a, 231b to 234b, and 231c to 234c. The local wiring 251 is connected to the dummy pads 231a and 232a. The local wiring 252 is connected to the dummy pads 231b and 232b. The local wiring 253 is connected to the dummy pads 231c and 232c. The local wiring 254 is connected to the dummy pads 233a and 234a. The local wiring 255 is connected to the dummy pads 233b and 234b. The local wiring 256 is connected to the dummy pads 233c and 234c.
[0145] 12(a), exposed portions (portions not surrounded by dummy gate wiring) are formed on the outer peripheries of nanosheets 221b to 224b in the Y and Z directions. Specifically, the side surface of nanosheet 221b on the left side of the drawing is not covered by dummy gate wiring 243, and the side surface of nanosheet 222b on the right side of the drawing is not covered by dummy gate wiring 243. The side surface of nanosheet 223b on the left side of the drawing is not covered by dummy gate wiring 247, and the side surface of nanosheet 224b on the right side of the drawing is not covered by dummy gate wiring 247.
[0146] That is, nanosheets 221b and 223b each have an exposed portion formed on the left side of the drawing (upper side in FIG. 11). Nanosheets 222b and 224b each have an exposed portion formed on the right side of the drawing (lower side in FIG. 11). Similarly, in FIG. 11, nanosheets 221a and 223a each have an exposed portion formed on the upper side of the drawing. Nanosheets 222a and 224a each have an exposed portion formed on the lower side of the drawing.
[0147] Therefore, the surfaces of the nanosheets 224a and 224b facing the nanosheet 21a of the inverter cell C2 (the surfaces on the lower side in FIG. 11) are exposed from the dummy gate wirings 246 and 247, respectively.
[0148] In FIG. 11, the nanosheets 221a to 224a and 221b to 224b are formed in the same layer as the nanosheets 21a to 24a.
[0149] The nanosheets 221a to 224a are formed at the same positions in the X direction as the nanosheets 21a to 24a.
[0150] The dummy pads 231a to 234a, 231b to 234b, and 231c to 234c are formed in the same layer as the pads 31a to 34a, and 31b to 34b.
[0151] The dummy pads 231a to 231c are formed at the same position in the Y direction and are arranged at a uniform pitch in the X direction. The dummy pads 232a to 232c are formed at the same position in the Y direction and are arranged at a uniform pitch in the X direction. The dummy pads 233a to 233c are formed at the same position in the Y direction and are arranged at a uniform pitch in the X direction. The dummy pads 234a to 234c are formed at the same position in the Y direction and are arranged at a uniform pitch in the X direction.
[0152] The dummy pads 231a to 234a are formed at the same positions in the X direction as the pads 31a to 34a. The dummy pads 231b to 234b are formed at the same positions in the X direction as the pads 31b to 34b.
[0153] The dummy gate wirings 241 to 248 are formed in the same layer as the gate wirings 41 and 43 and the dummy gate wirings 45 to .
[0154] The dummy gate wirings 241 to 244 are formed at the same position in the Y direction and are arranged at an equal pitch in the X direction. The dummy gate wirings 245 to 248 are formed at the same position in the Y direction and are arranged at an equal pitch in the X direction.
[0155] The upper and lower ends of the dummy gate wirings 241 to 244 in the drawing are aligned in the Y direction. The upper and lower ends of the dummy gate wirings 245 to 248 in the drawing are aligned in the Y direction.
[0156] The dummy gate wirings 241 and 245 are formed at the same position in the X direction as the dummy gate wirings 45 and 47. The dummy gate wirings 242 and 246 are formed at the same position in the X direction as the gate wirings 41 and 43. The dummy gate wirings 243 and 247 are formed at the same position in the X direction as the dummy gate wirings 46 and 48.
[0157] The local wirings 251-256 are formed in the same layer as the local wirings 51-53.
[0158] The local wirings 251 to 253 are formed at the same position in the Y direction and are arranged at an equal pitch in the X direction. The local wirings 254 to 256 are formed at the same position in the Y direction and are arranged at an equal pitch in the X direction.
[0159] The local wirings 251 and 254 are formed at the same position in the X direction as the local wirings 51 and 53. The local wirings 252 and 255 are formed at the same position in the X direction as the local wiring 52.
[0160] With the above configuration, the semiconductor integrated circuit device includes a plurality of cell rows CR each including a plurality of standard cells arranged in the X direction. The cell row CRC includes an inverter cell C2 having a logic function, and the topmost cell row CRT includes a terminal cell C21 having no logic function. The terminal cell C21 is arranged adjacent to the upper side of the inverter cell C2 in the drawing. The inverter cell C2 includes an N-well region 202 which is a region for forming a P-type transistor, a P-substrate region 201 which is a region for forming an N-type transistor, a nanosheet 21a extending in the X direction and formed in the N-well region 202, a nanosheet 24a extending in the X direction and formed in the P-substrate region 201 and formed at the same position as the nanosheet 21a in the X direction, a gate wiring 41 extending in the Y direction and surrounding the outer periphery of the nanosheet 21a in the Y direction and the Z direction, and a gate wiring 43 extending in the Y direction and surrounding the outer periphery of the nanosheet 24a in the Y direction and the Z direction. The terminal cell C21 extends in the X direction and includes a nanosheet 224a formed at the same position in the Y direction as the nanosheet 21a and adjacent to the nanosheet 21a in the Y direction, and a dummy gate wiring 246 extending in the Y direction and surrounding the outer periphery of the nanosheet 224a in the Y and Z directions. The upper surface of the nanosheet 21a in the drawing is exposed from the gate wiring 41. The lower surface of the nanosheet 24a in the drawing is exposed from the gate wiring 43. The lower surface of the nanosheet 224a in the drawing is exposed from the dummy gate wiring 246.
[0161] That is, the nanosheets 21a and 244a arranged adjacent to each other in the Y direction have opposing surfaces exposed from the gate wiring 41 and the dummy gate wiring 246. This makes it possible to suppress manufacturing variations in semiconductor integrated circuit devices, improve yields, and improve reliability.
[0162] Moreover, the nanosheets 21a and 224a are formed adjacent to each other in the Y direction. This eliminates the need for overlapping of gate wirings, including dummy gate wirings, between the nanosheets 21a and 224a, thereby making it possible to reduce the area of the semiconductor integrated circuit device.
[0163] Furthermore, the surfaces of the nanosheets 222a and 223a facing each other are exposed from the dummy gate wirings 242 and 246, respectively. This eliminates the need for overlapping of the gate wiring (dummy gate wiring) between the nanosheets 222a and 223a, making it possible to reduce the area of the semiconductor integrated circuit device.
[0164] Moreover, the nanosheets 221a to 224a, 221b to 224b are formed in the same layer as the nanosheets 21a to 24a. The dummy pads 231a to 234a, 231b to 234b, 231c to 234c are formed in the same layer as the pads 31a to 34a, 31b to 34b. The dummy gate wirings 241 to 248 are formed in the same layer as the gate wirings 41, 43 and the dummy gate wirings 45 to 48. The local wirings 251 to 256 are formed in the same layer as the local wirings 51 to 53. That is, by forming the nanosheets, dummy pads, dummy gate wirings, and local wirings in the terminal cells, the pads including the dummy pads, the gate wirings including the dummy gate wirings, and the local wirings are regularly arranged. This makes it possible to suppress the variation in the finished shape of the layout pattern of the cells arranged inside the terminal cells, and to suppress the manufacturing variation of the semiconductor integrated circuit device, improve the yield, and improve the reliability.
[0165] Moreover, the nanosheets 221a to 224a are formed at the same positions in the X direction as the nanosheets 21a to 24a. The dummy pads 231a to 234a are formed at the same positions in the X direction as the pads 31a to 34a, and the dummy pads 231b to 234b are formed at the same positions in the X direction as the pads 31b to 34b. The dummy gate wirings 241 and 245 are formed at the same positions in the X direction as the dummy gate wirings 45 and 47, the dummy gate wirings 242 and 246 are formed at the same positions in the X direction as the gate wirings 41 and 43, and the dummy gate wirings 243 and 247 are formed at the same positions in the X direction as the dummy gate wirings 46 and 48. The local wirings 251 and 254 are formed at the same positions in the X direction as the local wirings 51 and 53, and the local wirings 252 and 255 are formed at the same positions in the X direction as the local wiring 52. That is, in the terminal cell C21, a nanosheet, a dummy pad, a dummy gate wiring, and a local wiring are formed across the entire cell width. This makes it possible to suppress the variation in the finished shape of the layout pattern of the cells arranged inside the terminal cell, thereby suppressing the manufacturing variation of the semiconductor integrated circuit device, improving the yield, and improving the reliability.
[0166] The cell width of the terminal cell C21 may be wider or narrower than the size shown in FIG.
[0167] Furthermore, the termination cell C21 is provided with eight dummy transistors, ie, dummy transistors DP21 to DP24 and DN21 to DN24, but the number of dummy transistors provided in the termination cell C21 is not limited to eight.
[0168] Furthermore, in the terminal cell C21, eight dummy gate wirings, ie, the dummy gate wirings 241 to 248, are formed, but the number of dummy gate wirings provided in the terminal cell C21 is not limited to eight.
[0169] Furthermore, the terminal cell C21 is provided with six local wirings, ie, the local wirings 251 to 256, but the number of local wirings provided in the terminal cell C21 is not limited to six.
[0170] In addition, in FIG. 1, a terminal cell C21 may be placed in place of the standard cells C11a and C11c in the top row of cell column CRT, and a terminal cell C21a, which is the terminal cell C21 inverted in the Y direction, may be placed in place of the standard cells C11 and C11b in the bottom row of cell column CRB.
[0171] (Variation 1 of Termination Cell C21) 13A and 13B are plan views showing variations of the layout structure of the termination cell according to the second embodiment. Specifically, Fig. 13A is a plan view showing the layout structure of the termination cell C22, and Fig. 13B is a plan view showing the layout structure of the termination cell C23.
[0172] 13(a), compared with the termination cell C21, the cell size in the Y direction of the termination cell C22 is half, and the dummy transistors DN21-DN24, DP21, and DP22 are not formed. Specifically, the termination cell C22 does not have the P substrate region 201, the power supply wiring 211, the nanosheets 221a-221b, 222a-222b, and 223a-223b, the dummy pads 231a-231c, 232a-232c, and 233a-233c, the dummy gate wirings 241-244, and the local wirings 251-253.
[0173] 1, by disposing the termination cell C22 instead of the termination cell C21, it is possible to obtain the same effect as the termination cell C21. In addition, since the cell size of the termination cell C22 in the Y direction is smaller than that of the termination cell C21, it is possible to reduce the area of the semiconductor integrated circuit.
[0174] 13(b), the termination cell C23 is obtained by inverting the termination cell C22 in the Y direction and omitting the dummy transistor DP23. Specifically, the nanosheet 224a, the dummy pad 234a, and the local wiring 254 are not formed in the termination cell C23.
[0175] In Fig. 1, by placing the terminal cell C23 in place of the terminal cell C11 at the left end of the bottom row of cell column CRB, the same effect as the terminal cell C21 (terminal cell C11) can be obtained. In addition, since the cell size of the terminal cell C23 in the Y direction is smaller than that of the terminal cell C21, the area of the semiconductor integrated circuit can be reduced.
[0176] In addition, in FIG. 1, a terminal cell C22 may be placed in place of the standard cells C11a and C11c in the top row of cell column CRT, and a terminal cell C22 inverted in the Y direction may be placed in place of the standard cells C11 and C11b in the bottom row of cell column CRB.
[0177] (Variation 2 of Termination Cell C21) 14A to 14C are plan views showing variations of the layout structure of the termination cell according to the second embodiment. Specifically, Fig. 14A shows a plan view of the termination cell C24, Fig. 14B shows a plan view of the termination cell C25, and Fig. 14C shows a plan view of the termination cell C26.
[0178] In FIG. 1, when a standard cell C4 having a logic function is placed in place of the inverter cell C2, the terminating cells C24 to C26 are placed in place of the terminating cell C21.
[0179] In the terminal cell C21, two nanosheet FETs are provided for one dummy gate wiring, but in the terminal cells C24 to C26, one nanosheet is provided for one dummy gate wiring.
[0180] 14(a), nanosheets 222c, 222d, 223c, and 223d extending in the X and Y directions are formed in the terminal cell C24. The nanosheets 222c, 222d, 223c, and 223d overlap with the dummy gate wirings 242, 243, 246, and 247, respectively, in a plan view. The nanosheets 222c, 222d, 223c, and 223d form the channels of the dummy transistors DN25, DN26, DP25, and DP26, respectively.
[0181] Dummy pads 232d to 232f doped with an N-type semiconductor are formed on the left side of the nanosheet 222c in the figure, between the nanosheets 222c and 222d, and on the right side of the nanosheet 222d in the figure, respectively.
[0182] Dummy pads 233d to 233f doped with a P-type semiconductor are formed on the left side of the nanosheet 223c in the figure, between the nanosheets 223c and 223d, and on the right side of the nanosheet 223d in the figure, respectively.
[0183] The dummy pads 232d and 232e form a node of the dummy transistor DN25. The dummy pads 232e and 232f form a node of the dummy transistor DN26. The dummy pads 233d and 233e form a node of the dummy transistor DP25. The dummy pads 233e and 233f form a node of the dummy transistor DP26.
[0184] The dummy gate wiring 242 serves as the gate of the dummy transistor DN25, and the dummy gate wiring 243 serves as the gate of the dummy transistor DN26. The dummy gate wiring 246 serves as the gate of the dummy transistor DP25, and the dummy gate wiring 247 serves as the gate of the dummy transistor DP26.
[0185] The local wirings 251 to 256 are connected to the dummy pads 232d to 232f and 233d to 233f, respectively.
[0186] 14(a), exposed portions are formed on the outer peripheries of the nanosheets 222c, 222d, 223c, and 223d in the Y and Z directions, respectively. Specifically, the exposed portions are formed on the lower side of the nanosheets 222c and 222d in the figure. The exposed portions are formed on the upper side of the nanosheets 223c and 223d in the figure.
[0187] That is, in the terminal cell C24, the surfaces of the nanosheets 222c and 223c that face each other are exposed from the dummy gate wirings 242 and 246, respectively. The surfaces of the nanosheets 222d and 223d that face each other are exposed from the dummy gate wirings 243 and 247, respectively.
[0188] In FIG. 1, when a standard cell C4 having a logic function is arranged in place of the inverter cell C2, a terminal cell C24 is arranged in place of the terminal cell C21, and the same effect as that of the terminal cell C21 can be obtained.
[0189] 14(a), the nanosheets 223c and 223d have their lower side surfaces covered by the dummy gate wirings 246 and 247, respectively. That is, the opposing sides of the nanosheets 222c and 222d of the standard cell C4 and the nanosheets 22c and 22d of the terminal cell C24 are not exposed from the gate wiring including the dummy gate wiring. This makes it possible to suppress manufacturing variations in the semiconductor integrated circuit device, improve yields, and improve reliability.
[0190] 14(b), the cell size in the Y direction of the terminal cell C25 is half that of the terminal cell C24, and the dummy transistors DN25 and DN26 are not formed in the terminal cell C25. Specifically, the P substrate region 201, the power supply wiring 211, the nanosheets 222c and 222d, the dummy pads 232d-232f, the dummy gate wirings 241-244, and the local wirings 251-253 are not formed in the terminal cell C25.
[0191] 1, when a standard cell C4 having a logic function is placed in place of the inverter cell C2, the same effect as that of the termination cell C24 can be obtained by placing a termination cell C25 in place of the termination cell C21. In addition, since the cell size of the termination cell C25 in the Y direction is smaller than that of the termination cell C21, the area of the semiconductor integrated circuit can be reduced.
[0192] 14(c), compared with terminal cell C25, terminal cell C26 has a cell size in the Y direction that is half, and no exposed portion is formed on the outer periphery of nanosheets 223c, 223d in the Y direction and the Z direction. That is, the outer periphery of nanosheets 223c, 223d in the Y direction and the Z direction is surrounded by dummy gate wirings 245-248, respectively.
[0193] 1, when a standard cell C4 having a logic function is placed instead of the inverter cell C2, the same effect as that of the termination cell C24 can be obtained by placing a termination cell C26 instead of the termination cell C21. In addition, since the cell size of the termination cell C26 in the X direction is smaller than that of the termination cell C21, the area of the semiconductor integrated circuit can be reduced.
[0194] 1, the terminal cell C21a may be replaced by any one of the terminal cells C24-26 that is inverted in the Y direction. The terminal cells C11a and C11c of the topmost cell row CRT may be replaced by any one of the terminal cells C24-C26, and the terminal cells C11 and C11b of the bottommost cell row CRB may be replaced by any one of the terminal cells C24-C26 that is inverted in the Y direction.
[0195] Furthermore, in each of the above-described embodiments, each termination cell is arranged adjacent to the inverter cell C2, but this is not limiting, and each termination cell may be arranged adjacent to another standard cell.
[0196] Moreover, in each of the above-described embodiments, the number of nanosheets included in one nanosheet FET is not limited to three, and may be two or less or four or more.
[0197] In addition, in each of the above-described embodiments, the cross-sectional shape of the nanosheet is rectangular, but this is not limited thereto, and may be, for example, a square, a circle, an ellipse, or the like.
[0198] 1, the circuit block is rectangular, but is not limited to this. Also, the number of cell rows CR arranged in the circuit block is not limited to six. [Industrial Applicability]
[0199] The present disclosure can be applied to a semiconductor integrated circuit device having a standard cell using a fork sheet transistor, thereby making it possible to suppress manufacturing variations in the semiconductor integrated circuit device, improve yields, and improve reliability. [Explanation of symbols]
[0200] C1, C4 standard cells C2 inverter cell C3 NAND Cell C11, C12, C21~C26 Terminal cells 1,101,202 N-well region 2,102,201 P substrate area 11,21,111,112,211,211 Power wiring 21a-24a, 21b-24b, 22c, 22d, 23c, 23d, 121a-124a, 122c, 123c, 221a-224a, 221b-224b, 222c, 222d, 223c, 223d Nanosheets 31a~34a,31b~34b,31c~34c,32d~32f,33d~33f Pads 131a~134a, 131b~134b, 132c, 132d, 133c, 133d, 231a~234a, 231b~234b, 231c~234c, 232d~232f, 233d~233f Dummy pads 41~44 Gate wiring 45~48, 141~146, 241~248 Dummy gate wiring 51~58, 151~158, 251~256 Local wiring P1~P6, N1~N6 transistors DP11~DP13,DP21~DP26,DN11~DN13,DN21~DN26 Dummy transistors
Claims
1. a plurality of cell rows each including a plurality of standard cells arranged side by side in a first direction; a first cell row which is one of the plurality of cell rows includes a first standard cell having a logic function and a second standard cell which is arranged on at least one of both ends of the first cell row and does not have a logic function; The first standard cell is a first region in which a transistor of a first conductivity type is formed; a second region, which is a region for forming a transistor of a second conductivity type different from the first conductivity type, adjacent to the first region in a second direction perpendicular to the first direction; A first nanosheet extending in the first direction and formed in the first region; A second nanosheet extending in the first direction and formed in the second region; a first gate wiring extending in the second direction and surrounding an outer periphery of the first nanosheet in the second direction and in a third direction perpendicular to the first and second directions; a second gate wiring extending in the second direction and surrounding an outer periphery of the second nanosheet in the second and third directions; Equipped with The second standard cell is A third nanosheet extending in the first direction and formed at the same position as the first nanosheet in the second direction; A fourth nanosheet extending in the first direction and formed at the same position as the second nanosheet in the second direction; a first dummy gate wiring extending in the second direction and surrounding an outer periphery of the third nanosheet in the second and third directions; a second dummy gate wiring extending in the second direction and surrounding an outer periphery of the fourth nanosheet in the second and third directions; Equipped with the first nanosheet has a first side surface, which is one side in the second direction, exposed from the first gate wiring; the second nanosheet has a second side surface, which is one side in the second direction, exposed from the second gate wiring; the third nanosheet has a surface on the first side in the second direction exposed from the first dummy gate wiring, The fourth nanosheet has a surface on the second side in the second direction exposed from the second dummy gate wiring. A semiconductor integrated circuit device comprising:
2. 2. The semiconductor integrated circuit device according to claim 1, the first side is a side of the first nanosheet that faces the second region, The second side is the side of the second nanosheet facing the first region. A semiconductor integrated circuit device comprising:
3. 2. The semiconductor integrated circuit device according to claim 1, the first side is a side of the first nanosheet opposite the second region, The second side is the side of the second nanosheet opposite the first region. A semiconductor integrated circuit device comprising:
4. 2. The semiconductor integrated circuit device according to claim 1, The first standard cell is A fifth nanosheet extending in the first direction and formed in the first region; a sixth nanosheet extending in the first direction and formed in the second region; Further equipped with The second standard cell is A seventh nanosheet extending in the first direction and formed at the same position as the fifth nanosheet in the second direction; an eighth nanosheet extending in the first direction and formed at the same position as the sixth nanosheet in the second direction; Further equipped with the first gate wiring surrounds the periphery of the fifth nanosheet in the second and third directions; the second gate wiring surrounds the periphery of the sixth nanosheet in the second and third directions; the first dummy gate wiring surrounds the outer periphery of the seventh nanosheet in the second and third directions; the second dummy gate wiring surrounds the outer periphery of the eighth nanosheet in the second and third directions, the fifth nanosheet has a surface opposite to the first side in the second direction exposed from the first gate wiring, the sixth nanosheet has a surface opposite to the second side in the second direction exposed from the second gate wiring, the seventh nanosheet has a surface opposite to the first side in the second direction exposed from the first dummy gate wiring, The eighth nanosheet has a surface opposite to the second side in the second direction that is exposed from the second dummy gate wiring. A semiconductor integrated circuit device comprising:
5. 5. The semiconductor integrated circuit device according to claim 4, third and fourth dummy gate wirings extending in the second direction are formed on a cell boundary between the first and second standard cells; the first gate wiring and the first and third dummy gate wirings are arranged at an equal pitch in the first direction; The second gate wiring and the second and fourth dummy gate wirings are arranged at equal pitches in the first direction. A semiconductor integrated circuit device comprising:
6. Each of the standard cells includes a plurality of standard cells arranged side by side in a first direction, and a plurality of cell rows arranged side by side in a second direction perpendicular to the first direction; the plurality of cell rows include a first cell row including a first standard cell having a logic function, and a second cell row arranged on either one of both ends in the second direction in the plurality of cell rows, the second cell row including a second standard cell having no logic function; The first standard cell is a first region in which a transistor of a first conductivity type is formed; a second region adjacent to the first region in the second direction, the second region being a region for forming a transistor of a second conductivity type different from the first conductivity type; A first nanosheet extending in the first direction and formed in the first region; A second nanosheet extending in the first direction, formed in the second region, and formed at the same position as the first nanosheet in the first direction; a first gate wiring extending in the second direction and surrounding an outer periphery of the first nanosheet in the second direction and in a third direction perpendicular to the first and second directions; a second gate wiring extending in the second direction and surrounding an outer periphery of the second nanosheet in the second and third directions; Equipped with The second standard cell is A third nanosheet extending in the first direction, formed at the same position as the first nanosheet in the first direction, and formed adjacent to the first nanosheet in the second direction; a first dummy gate wiring extending in the second direction and surrounding an outer periphery of the third nanosheet in the second and third directions; Equipped with the first nanosheet has a first side surface, which is one side in the second direction, exposed from the first gate wiring; the second nanosheet has a second side surface, which is one side in the second direction, exposed from the second gate wiring; The first and third nanosheets have mutually opposing surfaces that are exposed from the first gate wiring and the first dummy gate wiring, respectively, or the first and third nanosheets have mutually opposing surfaces that are not exposed from the first gate wiring and the first dummy gate wiring, respectively. A semiconductor integrated circuit device comprising:
7. 7. The semiconductor integrated circuit device according to claim 6, The first side is a side of the first nanosheet that faces the third nanosheet, The third nanosheet has a surface facing the first nanosheet exposed from the first dummy gate wiring. A semiconductor integrated circuit device comprising:
8. 7. The semiconductor integrated circuit device according to claim 6, the first side is a side of the first nanosheet opposite the third nanosheet, The third nanosheet has a surface opposite to the first nanosheet, the surface being exposed from the first dummy gate wiring. A semiconductor integrated circuit device comprising:
9. 7. The semiconductor integrated circuit device according to claim 6, The second standard cell is A fourth nanosheet extending in the first direction and formed at the same position as the first nanosheet in the first direction; a second dummy gate wiring extending in the second direction and surrounding an outer periphery of the fourth nanosheet in the second and third directions; Further equipped with the third nanosheet has a surface opposite to the first side in the second direction exposed from the first dummy gate wiring, The fourth nanosheet has a surface opposite to the second side in the second direction that is exposed from the second dummy gate wiring. A semiconductor integrated circuit device comprising:
10. 10. The semiconductor integrated circuit device according to claim 9, The first standard cell is A fifth nanosheet extending in the first direction, formed in the first region, and formed at the same position as the first nanosheet in the first direction; a sixth nanosheet extending in the first direction, formed in the second region, and formed at the same position as the first nanosheet in the first direction; Further equipped with The second standard cell is A seventh nanosheet extending in the first direction and formed at the same position as the first nanosheet in the first direction; an eighth nanosheet extending in the first direction and formed at the same position as the first nanosheet in the first direction; Further equipped with the first gate wiring surrounds the periphery of the fifth nanosheet in the second and third directions; the second gate wiring surrounds the periphery of the sixth nanosheet in the second and third directions; the first dummy gate wiring surrounds the outer periphery of the seventh nanosheet in the second and third directions; the second dummy gate wiring surrounds the outer periphery of the eighth nanosheet in the second and third directions, the fifth nanosheet has a surface opposite to the first side in the second direction exposed from the first gate wiring, the sixth nanosheet has a surface opposite to the second side in the second direction exposed from the second gate wiring, the seventh nanosheet has a surface on the first side in the second direction exposed from the first dummy gate wiring, The eighth nanosheet has a surface on the second side in the second direction exposed from the second dummy gate wiring. A semiconductor integrated circuit device comprising:
11. 7. The semiconductor integrated circuit device according to claim 6, a first dummy gate wiring and a second dummy gate wiring, the first dummy gate wiring and the second dummy gate wiring being formed at the same position in the first direction;
Citation Information
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