Semiconductor device
View Patent ↗A semiconductor device includes a semiconductor substrate including a main surface; a plurality of first interconnections formed in a capacitance forming region defined on the main surface and extending in a predetermined direction; a plurality of second interconnections each adjacent to the first interconnection located at an edge of the capacitance forming region, extending in the predetermined direction, and having a fixed potential; and an insulating layer formed on the main surface and filling in between each of the first interconnections and between the first interconnection and the second interconnection adjacent to each other. The first interconnections and the second interconnections are located at substantially equal intervals in a plane parallel to the main surface, and located to align in a direction substantially perpendicular to the predetermined direction.
1. A semiconductor device, comprising:
a semiconductor substrate including a main surface;
a plurality of first interconnections formed in a predetermined region on said main surface and extending in a predetermined direction, one end of each of said plurality of first interconnection connecting to a second interconnection;
a plurality of third interconnections formed in said predetermined region and extending in said predetermined direction, one end of each of said plurality of third interconnection connecting to a fourth interconnection; and
a plurality of fifth interconnections each adjacent to one of said plurality of first interconnections and said plurality of third interconnections located at an edge of said predetermined region, extending in said predetermined direction, and having a fixed potential,
wherein said plurality of first interconnections and said plurality of third interconnections are located at substantially equal intervals in a first plane parallel to said main surface,
said second interconnection, said fourth interconnection and said fifth interconnections are located in said first plane,
one side of each of said plurality of first interconnections faces each of said plurality of third interconnections, and an another side of each of said plurality of first interconnections faces each of said plurality of third interconnections,
an insulating layer is formed on said main surface and fills in between each of said plurality of first interconnections, between each of said plurality of third interconnections, and between one of said plurality of first interconnections and said plurality of third interconnections and said fifth interconnection adjacent to each other,
said plurality of first interconnections, said plurality of third interconnections, and said plurality of fifth interconnections are located to align in a direction substantially perpendicular to said predetermined direction, and
a capacitance is formed by said plurality of first interconnections, said second interconnection, said plurality of third interconnections, said fourth interconnection and said insulating layer formed between each of said plurality of first interconnections and each of said plurality of third interconnections.
2. The semiconductor device according to claim 1 , wherein
said plurality of first interconnections and said plurality of third interconnections in said first plane are formed between said plurality of fifth interconnections.
3. The semiconductor device according to claim 1 , wherein
said plurality of first interconnections, said plurality of third interconnections and said plurality of fifth interconnections are formed in a plurality of said first planes spaced apart from each other.
4. The semiconductor device according to claim 3 , wherein
said plurality of first interconnections include a first interconnection located such that a distance from said main surface to said first interconnection adjacent to said main surface is greater than a distance between said plurality of first planes.
5. The semiconductor device according to claim 1 , further comprising a floating interconnection located in at least one of a position between said first interconnection and said main surface and a position between one of said plurality of first interconnections and said plurality of third interconnections and said fifth interconnection adjacent to each other, extending in said predetermined direction, and having a floating potential.
6. The semiconductor device according to claim 1 , further comprising a plurality of sixth interconnections spaced apart from each other in a second plane parallel to said main surface and extending in said predetermined direction,
wherein said predetermined region is located between said second plane and said main surface.
7. The semiconductor device according to claim 6 , further comprising a floating interconnection located between said first interconnection and said sixth interconnection, extending in said predetermined direction, and having a floating potential.
8. The semiconductor device according to claim 6 , wherein
said plurality of first interconnections and said plurality of third interconnections are formed in a plurality of said first planes spaced apart from each other, and
said plurality of first interconnections include a first interconnection located such that a distance from said second plane to said first interconnection adjacent to said second plane is greater than a distance between said plurality of first planes.
9. The semiconductor device according to claim 1 , wherein
said semiconductor substrate includes a first well layer of a first conductivity type extending in said main surface, said fifth interconnection electrically connected to said first well layer,
said first well layer being fixed at one of a ground potential and a power supply potential.
10. The semiconductor device according to claim 9 , wherein
said semiconductor substrate further includes a second well layer of a second conductivity type extending parallel to said first well layer at a position immediately below said predetermined region and apart from said main surface,
said second well layer being fixed at a potential different from the one of the ground potential and the power supply potential at which said first well layer is fixed.
11. The semiconductor device according to claim 1 , wherein the one of said plurality of first interconnections located at the edge of said predetermined region has impedance lower than that of another one of said plurality of first interconnections.
12. The semiconductor device according to claim 1 , wherein said semiconductor substrate includes a specific region defined in said main surface, and an area ratio of said specific region to a region of said main surface immediately above which said plurality of first interconnections, said second interconnection, said plurality of third interconnections, said fourth interconnection and said plurality of fifth interconnections are formed is not less than a predetermined value.
13. The semiconductor device according to claim 12 , wherein said specific region is located immediately below one of said plurality of first interconnections having relatively low impedance, and away from immediately below another one of said plurality of first interconnections having relatively high impedance.