Sapphire thin film coated flexible substrate

Patent metadata

Field	Value
Publication number	US-2018347028-A1
Application number	US-201816100186-A
Country	US
Kind code	A1
Filing date	Aug 9, 2018
Priority date	Dec 23, 2011
Publication date	Dec 6, 2018
Grant date	—

Abstract

A method to transfer a layer of harder thin film substrate onto a softer, flexible substrate. In particular, the present invention provides a method to deposit a layer of sapphire thin film on to a softer and flexible substrate e.g. PET, polymers, plastics, paper and fabrics. This combination provides the hardness of sapphire thin film to softer flexible substrates.

First claim

1 . A method for coating sapphire on to substrate comprising,
at least one e-beam evaporation or sputtering process, wherein sapphire is deposited on to at least one substrate to form a sapphire coated substrate, wherein the substrate during deposition is without external cooling or heating; and at least one annealing process, wherein said sapphire coated substrate is annealed under an annealing temperature ranging from 300° C. to less than a melting point of sapphire (Al 2 O 3 ) for a time.

2 . The method according to claim 1 , wherein said at least one substrate comprises at least one material with a Mohs value less than that of said sapphire.

3 . The method according to claim 1 , wherein said at least one substrate is selected from quartz, fused silica, silicon, glass, toughen glass, PET, polymers, and/or plastics.

4 . The method according to claim 1 , wherein said sapphire is deposited as at least one thin film on said at least one substrate.

5 . The method according to claim 4 , wherein a thickness of said at least one substrate is of one or more orders of magnitude greater than a thickness of said at least one sapphire thin film.

6 . The method according to claim 4 , wherein a thickness of said at least one sapphire thin film is about 1/1000 of a thickness of said at least one substrate.

7 . The method according to claim 4 , wherein said at least one sapphire thin film has the thickness between 150 nm and 600 nm.

8 . The method according to claim 1 , wherein said time is no less than 30 minutes.

9 . The method according to claim 1 , wherein said time is no more than 2 hours.

10 . The method according to claim 1 , wherein said annealing temperature ranges between 850° C. and 1300° C.

11 . The method according to claim 1 , wherein said annealing temperature ranges between 500° C. and 2040° C.

12 . The method according to claim 1 , wherein said annealing temperature ranges between 1150° C. and 1300° C.

13 . The method according to claim 1 , wherein said at least one substrate is first coated with at least one catalyst film comprising a metal selected from a group consisting of titanium (Ti), chromium (Cr), nickel (Ni), silicon (Si), silver (Ag), gold (Au), germanium (Ge) and metal with a higher melting point than the said at least one substrate, before said sapphire is deposited.

14 . The method according to claim 13 , wherein said at least one catalyst film is not continuous.

15 . The method according to claim 13 , wherein said at least one catalyst film has a thickness ranging between 1 nm and 15 nm.

16 . The method according to claim 13 , wherein said at least one catalyst film comprising a nano-dot with a diameter ranging between 5 nm and 20 nm.

17 . A method for protecting a surface of a substrate by coating said surface with sapphire comprising using the method according to claim 1 .

18 . The method according to claim 17 , wherein said surface allows light to pass through.

19 . A screen for use in display interfaces being fabricated by the method according to claim 1 .

20 . The screen according to claim 19 , wherein said screen is scratch resistant, shatter resistant, light in weight and/or allows light to pass through.

Assignees

• Univ Hong Kong Baptist Univ

Inventors

• Cheah Kok Wai
• Li King Fai
• Tam Hoi Lam
• Li Guixin
• Lam Wing Yui
• Chan Yu Wai

Classifications

• C23C14/5806

  Thermal treatment · CPC title

• C03C2217/214

  Al2O3 · CPC title

• C23C14/0005

  Separation of the coating from the substrate · CPC title

• C03C2217/78

  Coatings specially designed to be durable, e.g. scratch-resistant · CPC title

• C23C14/025

  Metallic sublayers · CPC title