Semiconductor device and semiconductor memory device, and method for manufacturing semiconductor device
A semiconductor device includes a substrate and an insulating film formed on the substrate, and an electrode layer comprising molybdenum, formed in contact with the insulating film. The electrode layer has a chlorine concentration gradient such that a first concentration of chlorine in a first portion of the electrode layer closer to the insulating layer is higher than a second concentration of chlorine in a second portion of the electrode layer less closer to the insulating layer.
1 . A semiconductor device comprising:
a substrate; and
an insulating film formed on the substrate, and an electrode layer comprising molybdenum, formed in contact with the insulating film,
wherein the electrode layer includes an initial layer, a first bulk layer, and a second bulk layer arranged in such an order from the insulating film, wherein the initial layer surrounds at least two surfaces of the first bulk layer, and the first bulk layer surrounds at least two surfaces of the second bulk layer, and wherein the electrode layer has a stabilized molybdenum concentration within a distance from an interface between the insulating film and the electrode layer, with a chlorine concentration decreasing with a distance from the second bulk layer.
2 . The semiconductor device according to claim 1 , wherein the electrode layer has an average chlorine concentration not less than 1×10 +18 (atoms/cm 3 ) within the distance, which is equal to about 10 nm.
3 . The semiconductor device according to claim 1 , wherein the initial layer is located closet closest to the insulating film;
the first bulk layer is located next closest to the insulating film; and
the second bulk layer is located least closest to the insulating film;
wherein the first bulk layer has a thickness not more than 5 nm; and wherein the electrode layer has an average chlorine concentration not less than 1×10 +18 (atoms/cm 3 ) within 10 nm from an interface between the insulating film and the initial layer.
4 . The semiconductor device according to claim 1 , wherein the electrode layer has an average crystal grain size not less than 14.5 nm.
5 . A semiconductor memory device comprising:
a substrate;
a plurality of insulating layers formed on the substrate, and a plurality of electrode layers comprising molybdenum, each of the plurality of electrode layers interposed between adjacent ones of the insulating layers and including an initial layer, a first bulk layer, and a second bulk layer arranged in such an order from a corresponding one of the insulating layers, the initial layer surrounding at least two surfaces of the first bulk layer, and the first bulk layer surrounding at least two surfaces of the second bulk layer; and
a columnar portion including a semiconductor body, a block film, and a charge storage film, the columnar portion extending through the electrode layers and the insulating layers,
wherein the electrode layers each have a stabilized molybdenum concentration within a distance from an interface between the insulating film and the electrode layer, with a chlorine concentration decreasing with a distance from the second bulk layer.
6 . The semiconductor memory device according to claim 5 , wherein each of the electrode layers has an average chlorine concentration not less than 1×10 +18 (atoms/cm 3 ) within the distance, which is equal to about 10 nm.
7 . The semiconductor memory device according to claim 5 , wherein each of the electrode layers has an average crystal grain size not less than 14.5 nm.