Semiconductor device and method for manufacturing the same
View Patent ↗According to the present invention, there is provided a method for manufacturing a semiconductor device, including the steps of forming an insulating film on a silicon substrate, forming a first conductive film on the insulating film, forming an aluminum crystal layer on the first conductive film, forming a ferroelectric film containing Pb(Zr x Ti 1-x )O 3 (where 0≦x≦1) on the aluminum crystal layer, forming a second conductive film on the ferroelectric film, and patterning the first conductive film, the ferroelectric film, and the second conductive film to form a capacitor including a lower electrode, a capacitor dielectric film, and an upper electrode which are laminated sequentially.
1. A method for manufacturing a semiconductor device, comprising:
forming an insulating film over a semiconductor substrate;
forming a first conductive film over the insulating film;
forming an aluminum crystal layer on the first conductive film;
forming a ferroelectric film containing Pb(Zr x Ti 1-x )O 3 (where 0≦x≦1) on the aluminum crystal layer;
forming a second conductive film on the ferroelectric film; and
patterning the first conductive film, the ferroelectric film, and the second conductive film to form a capacitor including a lower electrode, a capacitor dielectric film, an upper electrode which are sequentially stacked, wherein
the aluminum crystal layer is formed in a dotted pattern.
2. The method for manufacturing a semiconductor device according to claim 1 , wherein the orientation of the aluminum crystal layer is in a (111) direction.
3. The method for manufacturing a semiconductor device according to claim 1 , wherein the aluminum crystal layer is formed with a thickness of 5 nm or less.
4. The method for manufacturing a semiconductor device according to claim 1 , wherein the ferroelectric film is formed by an MOCVD (metal organic CVD) method.
5. The method for manufacturing a semiconductor device according to claim 1 , wherein an iridium film is formed as the first conductive film.
6. The method for manufacturing a semiconductor device according to claim 1 , wherein a film in which at least one of strontium, calcium, lanthanum, and niobium is contained in the Pb(Zr x Ti 1-x )O 3 is formed as the ferroelectric film.
7. The method for manufacturing a semiconductor device according to claim 1 , wherein a stacked film of a first ferroelectric film made of Pb(Zr x Ti 1-x )O 3 and a second ferroelectric film in which at least one of strontium, calcium, lanthanum, and niobium is contained in Pb(Zr x Ti 1-x )O 3 is formed as the ferroelectric film.
8. The method of manufacturing a semiconductor device according to claim 1 , wherein the first conductive film is formed by a DC sputtering method.
9. A method for manufacturing a semiconductor device, comprising:
forming an insulating film over a semiconductor substrate;
forming a first conductive film over the insulating film;
patterning the first conductive film to form a lower electrode;
forming an aluminum crystal layer on a side surface and an upper surface of the lower electrode;
forming a ferroelectric film containing Pb(Zr x Ti 1-x )O 3 (where 0≦x≦1) on the aluminum crystal layer and the insulating film;
forming a second conductive film on the ferroelectric film;
patterning the ferroelectric film to leave the ferroelectric film as a capacitor dielectric film on the side surface and the upper surface of the lower electrode; and
patterning the second conductive film to leave the second conductive film, as an upper electrode, over and beside a side of the lower electrode, and forming a capacitor with the upper electrode, the capacitor dielectric film, and the lower electrode.
10. The method for manufacturing a semiconductor device according to claim 9 , wherein an orientation of the aluminum crystal layer is in a (111) direction.
11. A semiconductor device comprising:
a semiconductor substrate;
an insulating film formed over the semiconductor substrate; and
a capacitor, which is formed on the insulating film, and which is formed by sequentially stacking a lower electrode, a capacitor dielectric film containing Pb(Zr x Ti 1-x )O 3 (where 0≦x≦1) and aluminum, and an upper electrode.
12. The semiconductor device according to claim 11 , wherein the lower electrode is made of iridium.