METHOD FOR MANUFACTURING A SEMICONDUCTOR MEMORY DEVICE
A method for forming a semiconductor device includes the following processes. An insulating film is formed over a semiconductor substrate. A hole is formed in the insulating film. A film including ZrAlO is formed over the insulating film and in the hole. Forming the film including ZrAlO may include, but is not limited to, the following processes. A first precursor including zirconium and a second precursor including aluminum are supplied into a reaction chamber at a supply amount ratio of the first precursor to the second precursor in the range from 2.5 to 3.5. The first precursor and the second precursor are exhausted from the reaction chamber. An oxidant is supplied into the reaction chamber to oxidize zirconium and aluminum. The oxidant is exhausted from the reaction chamber.
1 . A method for forming a semiconductor device, the method comprising:
forming an insulating film over a semiconductor substrate;
forming a hole in the insulating film; and
forming a film including ZrAlO over the insulating film and in the hole,
wherein forming the film including ZrAlO comprises:
supplying a first precursor including zirconium and a second precursor including aluminum into a reaction chamber at a supply amount ratio of the first precursor to the second precursor in the range from 2.5 to 3.5;
exhausting the first precursor and the second precursor from the reaction chamber;
supplying an oxidant into the reaction chamber to oxidize zirconium and aluminum; and
exhausting the oxidant from the reaction chamber.
2 . The method according to claim 1 , wherein the first precursor and the second precursor are supplied to the reaction chamber at substantially the same timing.
3 . The method according to claim 1 , wherein a first period of time of supplying the first precursor at least partially overlaps a second period of time of supplying the second precursor.
4 . The method according to claim 3 , wherein the second period of time is started during the first period of time.
5 . The method according to claim 3 , wherein supplying the first precursor and supplying the second precursor are finished at substantially the same timing.
6 . The method according to claim 1 , wherein forming the film including ZrAlO further comprises repeating a first cycle, and
the first cycle includes:
supplying the first precursor and the second precursor;
exhausting the first precursor and the second precursor;
supplying the oxidant; and
exhausting the oxidant.
7 . The method according to claim 6 , wherein forming the film including ZrAlO further comprises: a second cycle between the first cycles, and
the second cycle includes:
supplying the first precursor into the reaction chamber;
exhausting the first precursor from the reaction chamber;
supplying the oxidant into the reaction chamber to oxidize zirconium; and
exhausting the oxidant from the reaction chamber.
8 . The method according to claim 7 , wherein the number of performing the first cycle is less than the number of performing the second cycle.
9 . The method according to claim 1 , wherein the first precursor is tetrakis(ethylmethylamino)zirconium and the second precursor is trimethylaluminum.
10 . A method for forming a semiconductor device, the method comprising:
forming an insulating film over a semiconductor substrate;
forming a hole in the insulating film;
forming a conductive film over the insulating film and in the hole; and
forming a film including ZrAlO over the conductive film by atomic layer deposition,
wherein forming the film including ZrAlO comprises:
supplying a first precursor including zirconium and a second precursor including aluminum into a reaction chamber to form a mono-molecular layer so that a first molecular ratio of the first precursor in the mono-molecular layer at a bottom of the hole is substantially the same as a second molecular ratio of the first precursor in the mono-molecular layer over a top surface of the insulating film;
exhausting the first precursor and the second precursor from the reaction chamber;
supplying an oxidant to the reaction chamber to oxidize zirconium and aluminum; and
exhausting the oxidant from the reaction chamber.
11 . The method according to claim 10 , wherein the first precursor and the second precursor are supplied to the reaction chamber at substantially the same timing.
12 . The method according to claim 10 , wherein a first period of time of supplying the first precursor at least partially overlaps a second period of time of supplying the second precursor.
13 . The method according to claim 12 , wherein the second period of time is started during the first period of time.
14 . The method according to claim 12 , wherein supplying the first precursor and supplying the second precursor are finished at substantially the same timing.
15 . The method according to claim 10 , wherein forming the film including ZrAlO further comprises repeating a first cycle, and
the first cycle includes:
supplying the first precursor and the second precursor;
exhausting the first precursor and the second precursor;
supplying the oxidant; and
exhausting the oxidant.
16 . The method according to claim 15 , wherein forming the film including ZrAlO further comprises: a second cycle between the first cycles, and
the second cycle includes:
supplying the first precursor into the reaction chamber;
exhausting the first precursor from the reaction chamber;
supplying the oxidant to the reaction chamber to oxidize zirconium; and
exhausting the oxidant from the reaction chamber.
17 . The method according to claim 16 , wherein the number of performing the first cycle is less than the number of performing the second cycle.
18 . The method according to claim 10 , wherein the first precursor is tetrakis(ethylmethylamino)zirconium and the second precursor is trimethylaluminum.
19 . A method for forming a semiconductor device, the method comprising:
forming an insulating film over a semiconductor substrate;
forming a hole in the insulating film;
forming a first electrode in the hole;
forming a capacitive insulating film including ZrAlO over the conductive film and the insulating film; and
forming a second electrode over the capacitive insulating film,
wherein forming the capacitive insulating film comprises:
supplying a first precursor including zirconium and a second precursor including aluminum into a reaction chamber at a supply amount ratio of the first precursor to the second precursor in the range from 2.5 to 3.5;
exhausting the first precursor and the second precursor from the reaction chamber;
supplying an oxidant into the reaction chamber to oxidize zirconium and aluminum; and
exhausting the oxidant from the reaction chamber.
20 . The method according to claim 19 , wherein forming the hole comprises:
forming the hole in the insulating film so that an aspect ratio of the hole is from 20 to 30.