METHODS FOR TRANSFERRING GRAPHENE FILMS AND THE LIKE BETWEEN SUBSTRATES
Aspects of the invention are directed to a method of forming a thin film adhered to a target substrate. The method comprises the steps of: (i) forming the thin film on a deposition substrate; (ii) depositing a support layer on the thin film; (iii) removing the deposition substrate without substantially removing the thin film and the support layer; (iv) drying the thin film and the support layer while the thin film is only adhered to the support layer; (v) placing the dried thin film and the dried support layer on the target substrate such that the thin film adheres to the target substrate; and (vi) removing the support layer without substantially removing the thin film and the target substrate.
1 . A method of forming a thin film adhered to a target substrate, the method comprising the steps of:
(i) forming the thin film on a deposition substrate;
(ii) depositing a support layer on the thin film;
(iii) removing the deposition substrate without substantially removing the thin film and the support layer;
(iv) drying the thin film and the support layer while the thin film is only adhered to the support layer;
(v) placing the dried thin film and the dried support layer on the target substrate such that the thin film adheres to the target substrate; and
(vi) removing the support layer without substantially removing the thin film and the target substrate.
2 . The method of claim 1 , wherein the thin film comprises graphene.
3 . The method of claim 1 , wherein step (i) comprises chemical vapor deposition.
4 . The method of claim 3 , wherein the chemical vapor deposition utilizes at least methane and hydrogen.
5 . The method of claim 1 , wherein the deposition substrate comprises copper.
6 . The method of claim 1 , wherein step (ii) comprises depositing a liquid on the thin film, the liquid adapted to harden into the support layer at least in part by evaporation of a solvent.
7 . The method of claim 6 , wherein the solvent comprises at least one of an acetate, a ketone, and propane.
8 . The method of claim 6 , wherein the liquid comprises a plasticizer.
9 . The method of claim 1 , wherein the support layer is adapted to support the thin film after step (iii) and before step (vi) such that the support layer and the thin film can be supported at a corner or an edge without the thin film tearing or cracking
10 . The method of claim 1 , wherein step (ii) comprises at least one of spray coating, dip coating, and spin coating.
11 . The method of claim 1 , wherein the support layer comprises a material that is substantially removed by acetone.
12 . The method of claim 1 , wherein the support layer is not substantially etched by water.
13 . The method of claim 1 , wherein the support layer comprises a polymeric material.
14 . The method of claim 1 , wherein the support layer comprises nitrocellulose.
15 . The method of claim 1 , wherein the support layer comprises polyurethane.
16 . The method of claim 1 , wherein the support layer comprises polycrylic.
17 . The method of claim 1 , wherein step (iii) comprises wet chemical etching in a solution comprising at least one of iron chloride and iron nitrate.
18 . The method of claim 1 , wherein step (iv) is performed by evaporation.
19 . The method of claim 1 , further comprising the step of washing the thin film after step (iii) and before step (iv).
20 . The method of claim 19 , wherein the washing step comprises floating the thin film and the support layer on a liquid bath with the thin film facing downward.
21 . The method of claim 19 , wherein the washing step comprises exposing the thin film to a liquid spray.
22 . The method of claim 1 , wherein the target substrate comprises at least one of aluminum, copper, nickel, silicon dioxide, sapphire, quartz, polyethylene terephthalate, and stainless steel.
23 . The method of claim 1 , wherein step (v) comprises the steps of:
floating the dried thin film and the dried support layer on a liquid with the thin film facing downward;
immersing the target substrate in the liquid under the floating thin film;
raising the target substrate upward until the target substrate supports the thin film and the support layer; and
drying the thin film and the target substrate to cause the thin film to adhere to the target substrate.
24 . The method of claim 1 , wherein step (v) comprises the steps of:
wetting a surface of the target substrate without immersing the target substrate in a liquid;
disposing the dried thin film and the dried support layer on the wetted surface such that the thin film contacts the wetted surface; and
drying the wetted surface to cause the thin film to adhere to the target substrate.
25 . The method of claim 1 , wherein step (vi) is performed using a solution comprising acetone.