Semiconductor device including a transistor and a ferroelectric capacitor
According to an aspect of the present invention, there is provided a semiconductor device including: a transistor including: a source, a drain and a gate; first and second plugs on the source and the drain; a third plug on the gate to have a top face higher than that of the first plug; an interlayer insulating film covering the transistor and the first to the third plugs; a ferroelectric capacitor on the interlayer insulating film, one electrode thereof being connected to the first plug; a barrier film covering surfaces of the ferroelectric capacitor and the interlayer insulating film to prevent a substance affecting the ferroelectric capacitor from entering therethrough; and fourth and fifth plugs disposed on the second and the third plugs and connected thereto through connection holes formed in the barrier film.
1. A semiconductor device comprising:
a transistor including:
a first main electrode,
a second main electrode, and
a control electrode;
a first plug that is disposed on the first main electrode;
a second plug that is disposed on the second main electrode;
a third plug that is disposed on the control electrode and has a top face set higher than a top face of the first plug;
an interlayer insulating film that is disposed to cover the transistor, the first plug, the second plug and the third plug;
a ferroelectric capacitor including:
a first electrode that is disposed on the interlayer insulating film and is electrically connected to the first plug,
a second electrode that is separated from the first electrode, and a ferroelectric film that is disposed between the first electrode and the second electrode;
a barrier film that covers a surface of the ferroelectric capacitor and a surface of the interlayer insulating film and prevents a substance affecting a crystalline composition or a polarization characteristic of a ferroelectric from entering therethrough;
a fourth plug that is disposed on the second plug and is electrically connected to the second plug through a first connection hole disposed in the barrier film;
a fifth plug that is disposed on the third plug and is electrically connected to the third plug through a second connection hole disposed in the barrier film;
a sixth plug that is disposed between the first plug and the first electrode; and
a seventh plug that is disposed between the second plug and the fourth plug below the barrier film so that a top face of the seventh plug is lower than a bottom surface of the barrier film,
wherein the top surface of the seventh plug is lower than a top surface of the sixth plug, and
wherein a bottom surface of the seventh plug is in the same level with a bottom face of the sixth plug.
2. The semiconductor device according to claim 1 further comprising:
a semiconductor substrate,
wherein the transistor and the ferroelectric capacitor are disposed on a surface of the semiconductor substrate.
3. The semiconductor device according to claim 2 ,
wherein a height of the third plug from the surface of the semiconductor substrate to the top face thereof is higher than a height of the first plug from the surface of the semiconductor substrate to the top face thereof.
4. The semiconductor device according to claim 1 ,
wherein a length from a bottom face to the top face of the third plug is smaller than a length from a bottom face to the top face of the first plug and is larger than a thickness of the barrier film.
5. The semiconductor device according to claim 1 ,
wherein the interlayer insulating film includes:
a first insulating film that covers the transistor,
a second insulating film that is disposed on the first insulating film,
a third insulating film that is disposed on the second insulating film,
a fourth insulating film that is disposed on the third insulating film, and
a fifth insulating film that is disposed on the fourth insulating film.
6. The semiconductor device according to claim 1 ,
wherein each of the first to the fifth plugs includes:
a barrier metal that forms a bottom face and a side face thereof, and
a burying conductor that is disposed on the barrier metal.
7. A semiconductor device comprising:
a transistor including:
a first main electrode,
a second main electrode, and
a control electrode;
a first plug that is disposed on the first main electrode;
a second plug that is disposed on the second main electrode;
a third plug that is disposed on the control electrode and has a top face set higher than a top face of the first plug;
an interlayer insulating film that is disposed to cover the transistor, the first plug, the second plug and the third plug;
a ferroelectric capacitor including:
a first electrode that is disposed on the interlayer insulating film and is electrically connected to the first plug,
a second electrode that is separated from the first electrode, and
a ferroelectric film that is disposed between the first electrode and the second electrode;
a barrier film that covers a surface of the ferroelectric capacitor and a surface of the interlayer insulating film and prevents a substance affecting a crystalline composition or a polarization characteristic of a ferroelectric from entering therethrough;
a fourth plug that is disposed on the second plug and is electrically connected to the second plug through a first connection hole disposed in the barrier film;
fifth plug that is disposed on the third plug and is electrically connected to the third plug through a second connection hole disposed in the barrier film;
wherein the interlayer insulating film includes,
a first insulating film that covers the transistor,
a second insulating film that is disposed on the first insulating film,
a third insulating film that is disposed on the second insulating film,
a fourth insulating film that is disposed on the third insulating film, and
a fifth insulating film that is disposed on the fourth insulating film;
wherein the fourth and the fifth insulating films is removed except a region under the ferroelectric capacitor.
8. A semiconductor device comprising:
a transistor including:
a first main electrode,
a second main electrode, and
a control electrode;
a first plug that is disposed on the first main electrode;
a second plug that is disposed on the second main electrode;
a third plug that is disposed on the control electrode and has a top face set higher than a top face of the first plug;
an interlayer insulating film that is disposed to cover the transistor, the first plug, the second plug and the third plug;
a ferroelectric capacitor including:
a first electrode that is disposed on the interlayer insulating film and is electrically connected to the first plug,
a second electrode that is separated from the first electrode, and a ferroelectric film that is disposed between the first electrode and the second electrode;
a barrier film that covers a surface of the ferroelectric capacitor and a surface of the interlayer insulating film and prevents a substance affecting a crystalline composition or a polarization characteristic of a ferroelectric from entering therethrough;
a fourth plug that is disposed on the second plug and is electrically connected to the second plug through a first connection hole disposed in the barrier film;
a fifth plug that is disposed on the third plug and is electrically connected to the third plug through a second connection hole disposed in the barrier film;
wherein the interlayer insulating film includes,
a first insulating film that covers the transistor,
a second insulating film that is disposed on the first insulating film,
a third insulating film that is disposed on the second insulating film,
a fourth insulating film that is disposed on the third insulating film, and
a fifth insulating film that is disposed on the fourth insulating film;
wherein the top face of the first plug is in the same level with a top face of the third insulating film, and
wherein the top face of the third plug is in the same level with a top face of the fourth insulating film.