Layer stack for display applications
Embodiments of the present disclosure generally relate to a layer stack including a high K dielectric layer formed over a first dielectric layer and a metal electrode. The high K dielectric layer has a K value of 20 or higher and may be formed as a part of a capacitor, a gate insulating layer, or any suitable insulating layer in electronic devices, such as display devices. The layer stack includes a second dielectric layer disposed on the first dielectric layer and the metal layer, and the high K dielectric layer disposed on the second dielectric layer. The second dielectric layer provides a homogenous surface on which the high K dielectric layer is formed. The homogeneous surface enables the high K dielectric material to be deposited uniformly thereover, resulting in a uniform thickness profile.
1. A structure, comprising:
a first dielectric layer;
a first metal electrode disposed on the first dielectric layer;
a layer stack disposed on the first dielectric layer and the first metal electrode, the layer stack comprising:
a second dielectric layer disposed on and in contact with the first dielectric layer and the first metal electrode;
a high K dielectric layer disposed on and in contact with the second dielectric layer, the high K dielectric layer being distinct from the second dielectric layer, the high K dielectric layer comprising zirconium dioxide or hafnium dioxide, the high K dielectric layer being in contact with the second dielectric layer at a location over the first metal electrode; and
a silicon nitride layer disposed on and in contact with the high K dielectric layer;
a second metal electrode conformally disposed on and in contact with the silicon nitride layer; and
a third dielectric layer conformally disposed on the second electrode.
2. The structure of claim 1 , wherein the second dielectric layer comprises silicon dioxide, aluminum oxide, titanium dioxide, or yttrium (III) oxide.
3. The structure of claim 2 , wherein the second dielectric layer has a thickness ranging from about 2 Angstroms to about 100 Angstroms.
4. The structure of claim 1 , wherein the high K dielectric layer has a thickness ranging from about 250 Angstroms to about 900 Angstroms.
5. The structure of claim 1 , wherein the first dielectric layer comprises silicon nitride or silicon dioxide.
6. The structure of claim 5 , wherein the first metal electrode comprises an aluminum layer or a molybdenum layer.
7. The structure of claim 6 , wherein the aluminum layer is disposed between two titanium layers.
8. The structure of claim 1 , wherein the first dielectric layer comprises the same material as the second dielectric layer.
9. The structure of claim 1 , wherein the high K dielectric layer has a cubic or tetragonal phase crystalline structure.
10. A structure, comprising:
a first dielectric layer;
a first metal electrode disposed on the first dielectric layer;
a layer stack disposed on the first dielectric layer and the first metal electrode, the layer stack comprising:
a second dielectric layer disposed on and in contact with the first dielectric layer and the first metal electrode, the second dielectric layer comprising a different material than the first dielectric layer;
a high K dielectric layer disposed on and in contact with the second dielectric layer, the high K dielectric layer being distinct from the second dielectric layer, the high K dielectric layer comprising zirconium dioxide or hafnium dioxide, the high K dielectric layer being in contact with the second dielectric layer at a location over the first metal electrode; and
a silicon nitride layer disposed on and in contact with the high K dielectric layer;
a second metal electrode conformally disposed on and in contact with the silicon nitride layer; and
a third dielectric layer conformally disposed on the second electrode.
11. The structure of claim 10 , wherein the second dielectric layer comprises aluminum oxide, titanium dioxide, or yttrium (III) oxide.
12. The structure of claim 11 , wherein the second dielectric layer has a thickness ranging from about 2 Angstroms to about 100 Angstroms.
13. The structure of claim 10 , wherein the high K dielectric layer has a thickness ranging from about 250 Angstroms to about 900 Angstroms.
14. The structure of claim 10 , wherein the first dielectric layer comprises silicon nitride or silicon dioxide.
15. The structure of claim 14 , wherein the first metal electrode comprises an aluminum layer or a molybdenum layer.
16. The structure of claim 15 , wherein the aluminum layer is disposed between two titanium layers.
17. The structure of claim 10 , wherein the high K dielectric layer has a cubic or tetragonal phase crystalline structure.
18. A structure, comprising:
a first dielectric layer;
a first metal electrode disposed on the first dielectric layer;
a layer stack disposed on the first dielectric layer and the first metal electrode, the layer stack consisting essentially of a second dielectric layer, a high K dielectric layer, and a silicon nitride layer, wherein:
the second dielectric layer disposed on and in contact with the first dielectric layer and the first metal electrode; and
the high K dielectric layer disposed on and in contact with the second dielectric layer, the high K dielectric layer being distinct from the second dielectric layer, the high K dielectric layer comprising zirconium dioxide or hafnium dioxide, the high K dielectric layer being in contact with the second dielectric layer at a location over the first metal electrode; and
the silicon nitride layer disposed on the high K dielectric layer, the silicon nitride layer being in contact with the high K dielectric layer at a location over the first metal electrode;
a second metal electrode conformally disposed on and in contact with the layer stack; and
a third dielectric layer conformally disposed on and in contact with the second electrode.
19. The structure of claim 18 , wherein the second dielectric layer comprises silicon dioxide, aluminum oxide, titanium dioxide, or yttrium (III) oxide, and wherein the second dielectric layer has a thickness ranging from about 2 Angstroms to about 100 Angstroms.
20. The structure of claim 18 , wherein the first metal electrode comprises an aluminum layer disposed between two titanium layers.