Thin metal films having an ultra-flat surface and methods of preparing the same
View Patent ↗The present disclosure relates generally to thin metal films having an ultra-flat surface and methods of their preparation. In particular, the ultra-flat thin metal films comprise FCC metals. Preferably, the thin metal films are attached to a substrate. Preferred substrates comprise chalcogenides and dichalcogenides. Beneficially, the thin metal films described herein can be prepared at ambient temperatures.
1 . A thin film composition comprising:
a substrate and a metal, wherein the metal has a first side and a second side, wherein the first side is attached to the substrate forming an interface, wherein the interface is opposed to the second side, and wherein the second side is a continuous flat surface; wherein the continuous flat surface has a surface roughness of less than 200 pm as measured by scanning tunneling microscopy;
wherein the substrate comprises MoS 2 , and
wherein the metal comprises gold and has a thickness of at least about 7.0 nm.
2 . The thin film composition of claim 1 , wherein the gold has a thickness between 7.0 nm and up to about 200 nm.
3 . The thin film composition of claim 1 , wherein the continuous flat surface has a surface roughness of less than about 100 pm as measured by scanning tunneling microscopy.
4 . The thin film composition of claim 1 , wherein the continuous flat surface is a reflective coating.
5 . A method of preparing the thin metal film composition of claim 1 comprising:
(a) depositing the gold on the MoS 2 substrate to form a thin metal film; wherein the depositing step is performed under vacuum conditions and at a temperature of at least about 0° C.; and
(b) annealing the thin metal film; wherein the annealing is performed for a time between about 1 minute and about 20 hours; and wherein the annealing is performed at a temperature up to about 1000° C.
6 . The method of claim 5 , wherein the depositing step is performed by vacuum evaporation, sputtering, laser ablation, chemical vapor deposition, molecular beam epitaxy, or electroplating.
7 . The method of claim 5 , wherein the gold has a thickness between 7.0 nm and up to about 200 nm; and wherein the continuous surface has a surface roughness of less than about 100 pm.