Ferroelectric memory device
A ferroelectric memory device includes a channel layer, a gate insulation layer on the channel layer, and a gate electrode layer on the gate insulation layer. The gate insulation layer includes a ferroelectric inductive layer and a ferroelectric stack structure on the ferroelectric inductive layer, and the ferroelectric stack structure is stacked in an order or reverse order of a ferroelectric layer and a non-ferroelectric layer.
1 . A ferroelectric memory device, comprising:
a channel layer;
a gate insulation layer on the channel layer; and
a gate electrode layer on the gate insulation layer, the gate insulation layer including:
a ferroelectric inductive layer, and
a ferroelectric stack structure on the ferroelectric inductive layer, the ferroelectric stack structure including a stack of a ferroelectric layer and a non-ferroelectric layer:
wherein at least one of the ferroelectric inductive layer, the ferroelectric layer or the non-ferroelectric layer includes a two-dimensional material.
2 . The ferroelectric memory device as claimed in claim 1 , wherein the ferroelectric layer includes a two-dimensional transition metal dichalcogenide layer.
3 . The ferroelectric memory device as claimed in claim 2 , wherein the two-dimensional transition metal dichalcogenide layer includes an MX 2 layer having a 3R-type rhombohedral crystal structure, M including one or more of molybdenum (Mo), tungsten (W), and zirconium (Zr), and X including one or more of sulfur(S), selenium (Se), and tellurium (Te).
4 . The ferroelectric memory device as claimed in claim 3 , wherein the non-ferroelectric layer includes a nitride having a hexagonal crystal structure, as a two-dimensional material.
5 . The ferroelectric memory device as claimed in claim 2 , wherein the ferroelectric layer includes a nitride having a hexagonal crystal structure, as a two-dimensional material.
6 . The ferroelectric memory device as claimed in claim 1 , wherein the ferroelectric stack structure includes a plurality of ferroelectric stack structure units, each of the plurality of ferroelectric stack structure units including the stack of the ferroelectric layer and the non-ferroelectric layer.
7 . The ferroelectric memory device as claimed in claim 1 , wherein the ferroelectric layer includes hafnium oxide, zirconium oxide, hafnium zirconium oxide, or a combination thereof.
8 . The ferroelectric memory device as claimed in claim 7 , wherein the ferroelectric inductive layer includes a first ferroelectric inductive layer, an oxygen-reactive layer, and a second ferroelectric inductive layer, which are sequentially stacked.
9 . The ferroelectric memory device as claimed in claim 8 , wherein each of the first ferroelectric inductive layer and the second ferroelectric inductive layer includes hafnium oxide, zirconium oxide, hafnium zirconium oxide, or a combination thereof.
10 . The ferroelectric memory device as claimed in claim 8 , wherein the oxygen-reactive layer includes a silicon oxide, the silicon oxide being reactive with oxygen.
11 . The ferroelectric memory device as claimed in claim 8 , further comprising an interface layer between the channel layer and the first ferroelectric inductive layer.
12 . A ferroelectric memory device, comprising:
a channel layer;
a gate insulation layer on the channel layer; and
a gate electrode layer on the gate insulation layer, the gate insulation layer including:
a ferroelectric inductive layer, and
a ferroelectric stack structure on the ferroelectric inductive layer, the ferroelectric stack structure having a stack of a ferroelectric layer and a non-ferroelectric layer and including a two-dimensional transition metal dichalcogenide layer.
13 . The ferroelectric memory device as claimed in claim 12 , wherein the two-dimensional transition metal dichalcogenide layer includes an MX 2 layer having a 3R-type rhombohedral crystal structure, M including one or more of molybdenum (Mo), tungsten (W), and zirconium (Zr), and X including one or more of sulfur(S), selenium (Se), and tellurium (Te).
14 . The ferroelectric memory device as claimed in claim 13 , wherein the non-ferroelectric layer includes a nitride having a hexagonal crystal structure, as a two-dimensional material.
15 . The ferroelectric memory device as claimed in claim 12 , wherein the ferroelectric inductive layer includes a nitride having a hexagonal crystal structure.
16 . The ferroelectric memory device as claimed in claim 12 , wherein the ferroelectric stack structure includes a plurality of ferroelectric stack structure units, each of the plurality of ferroelectric stack structure units including the stack of the ferroelectric layer and the non-ferroelectric layer.
17 . A ferroelectric memory device, comprising:
a channel layer;
a gate insulation layer on the channel layer; and
a gate electrode layer on the gate insulation layer, the gate insulation layer including:
a ferroelectric inductive layer, and
a ferroelectric stack structure on the ferroelectric inductive layer, the ferroelectric stack structure including a stack of a non-ferroelectric layer and a ferroelectric layer,
wherein the ferroelectric inductive layer includes a first ferroelectric inductive layer, an oxygen-reactive layer, and a second ferroelectric inductive layer, which are sequentially stacked.
18 . The ferroelectric memory device as claimed in claim 17 , wherein the ferroelectric layer includes hafnium oxide, zirconium oxide, hafnium zirconium oxide, or a combination thereof.
19 . The ferroelectric memory device as claimed in claim 17 , wherein:
each of the first ferroelectric inductive layer and the second ferroelectric inductive layer includes hafnium oxide, zirconium oxide, hafnium zirconium oxide, or a combination thereof, and
the oxygen-reactive layer includes silicon oxide capable of reacting with oxygen.
20 . The ferroelectric memory device as claimed in claim 17 , wherein the ferroelectric stack structure includes a plurality of ferroelectric stack structure units, each of the plurality of ferroelectric stack structure units including the stack of the ferroelectric layer and the non-ferroelectric layer.