Thin free-standing oxide membranes
This disclosure provides systems, methods, and apparatus related to thin free-standing oxide membranes. In one aspect, a method includes providing a substrate. The substrate defines a hole having a diameter of about 500 nanometers to 5000 nanometers. A layer of metal is deposited on the substrate. A supporting layer is deposited on the layer of metal. A first side of the supporting layer is the side that is disposed on the layer of metal. A metal oxide layer is deposited on the first side of the supporting layer and on the substrate. In some implementations, the method further includes removing the supporting layer.
1. A method comprising:
providing a layer of silicon nitride, the layer of silicon nitride having a hole therein, the hole having a diameter of about 500 nanometers to 5000 nanometers;
depositing a layer of metal on the layer of silicon nitride;
depositing a supporting layer on the layer of metal, a first side of the supporting layer being the side that is disposed on the layer of metal; and
depositing a metal oxide layer on the first side of the supporting layer and on the layer of silicon nitride.
2. The method of claim 1 , further comprising:
removing the supporting layer.
3. The method of claim 1 , wherein the metal layer is gold (Au).
4. The method of claim 1 , wherein the supporting layer is graphene or a polymer.
5. The method of claim 1 , wherein the supporting layer is a polymer from the group consisting of polyvinyl formal and polymethyl methacrylate (PMMA).
6. The method of claim 1 , wherein depositing the metal oxide layer is performed using atomic layer deposition (ALD).
7. The method of claim 1 , wherein the metal oxide layer is a metal oxide from the group consisting of titanium dioxide (TiO 2 ), aluminum oxide (Al 2 O 3 ), silicon dioxide (SiO 2 ), hafnium dioxide (HfO 2 ), and a cobalt oxide (CoO x ).
8. The method of claim 1 , wherein the metal oxide layer is amorphous.
9. The method of claim 1 , wherein the metal oxide layer is about 1 nanometer to 20 nanometers thick.
10. A method comprising:
providing a layer of silicon nitride, the layer of silicon nitride having a hole therein, the hole having a diameter of about 500 nanometers to 5000 nanometers;
depositing a layer of metal on the layer of silicon nitride;
depositing a supporting layer on the layer of metal, the supporting layer being a polymer, a first side of the supporting layer being the side that is disposed on the layer of metal; and
depositing a metal oxide layer on a second side of the supporting layer.
11. The method of claim 10 , further comprising:
removing the supporting layer that is exposed by the hole in the layer of silicon nitride.
12. The method of claim 10 , wherein the metal layer is gold (Au).
13. The method of claim 10 , wherein the polymer is a polymer from the group consisting of polyvinyl formal and polymethyl methacrylate (PMMA).
14. The method of claim 10 , wherein depositing the metal oxide layer is performed using atomic layer deposition (ALD).
15. The method of claim 10 , wherein the metal oxide layer is a metal oxide from the group consisting of titanium dioxide (TiO 2 ), aluminum oxide (Al 2 O 3 ), silicon dioxide (SiO 2 ), hafnium dioxide (HfO 2 ), and a cobalt oxide (CoO x ).
16. The method of claim 10 , wherein the metal oxide layer is amorphous.
17. The method of claim 10 , wherein the metal oxide layer is about 1 nanometer to 20 nanometers thick.