Semiconductor device having capacitor capable of reducing additional processes and its manufacture method
View Patent ↗A first capacitor recess and a wiring trench are formed through an interlayer insulating film. A lower electrode fills the first capacitor recess, and a first wiring fills the wiring trench. An etching stopper film and a via layer insulating film are disposed over the interlayer insulating film. A first via hole extends through the via layer insulating film and etching stopper film and reaches the first wiring, and a first plug fills the first via hole. A second capacitor recess is formed through the via layer insulating film, the second capacitor recess at least partially overlapping the lower electrode, as viewed in plan. The upper electrode covers the bottom and side surfaces of the second capacitor recess. A capacitor is constituted of the upper electrode, etching stopper film and lower electrode. A second wring connected to the first plug is formed over the via layer insulating film.
1. A semiconductor device comprising:
a semiconductor substrate;
a first interlayer insulating film formed over the semiconductor substrate;
a first capacitor recess and a wiring trench formed in the first interlayer insulating film;
a lower electrode formed in the first capacitor recess;
a first wiring formed in the wiring trench;
a first etching stopper film disposed over the first interlayer insulating film;
a via layer insulating film disposed over the first etching stopper film and that includes insulating material having an etching resistance different from an etching resistance of the first etching stopper film;
a first via hole formed in the via layer insulating film and the first etching stopper film and that reaches an upper surface of the first wiring;
a first plug, that include conductive material, formed in the first via hole;
a second capacitor recess formed in the via layer insulating film and that reaches the first etching stopper film, the second capacitor recess at least partially overlapping the lower electrode as viewed in plan; and
an upper electrode disposed covering a bottom surface and a side surface of the second capacitor recess and a partial upper surface of the via layer insulating film continuous with the second capacitor recess, the upper electrode and the lower electrode constituting a capacitor comprising the first etching stopper film as a capacitor dielectric film, wherein
an outer peripheral line of the second capacitor recess is disposed outside an outer peripheral line of the lower electrode, as viewed in plan.
2. The semiconductor device according to claim 1 , further comprising a third wiring disposed below the first interlayer insulating film, wherein the lower electrode is connected to the third wiring via a conductive member formed in a second via hole extending downward from a bottom of the lower electrode.
3. The semiconductor device according to claim 1 , further comprising
a second etching stopper film formed on the first etching stopper film; and
a third etching stopper film formed on the second etching film and under the via layer insulating film,
wherein the second etching stopper film has an etching resistance different from etching resistances of the first etching stopper film and third etching stopper film, and
the third etching stopper film has an etching resistance different from an etching resistance of the via layer insulating film.
4. The semiconductor device according to claim 1 , wherein the upper electrode reaches an upper surface of the first plug, and is electrically connected to the first wiring via the first plug.
5. The semiconductor device according to claim 1 , wherein the first etching stopper film includes a recess located along the outer peripheral line of the second capacitor recess.