Sapphire thin film coated substrate
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. quartz, fused silica, silicon, glass, toughened glass, PET, polymers, plastics, paper and fabrics. This combination provides the hardness of sapphire thin film to softer flexible substrates.
1. A method for coating sapphire on to a substrate comprising,
an e-beam evaporation or sputtering deposition process at room temperature or 25° C., wherein sapphire is deposited directly on to a substrate selected from quartz, fused silica, silicon, glass, or toughened glass to form a sapphire coated substrate, wherein the substrate during deposition is without external cooling or heating; and
an annealing process, wherein said sapphire coated substrate is annealed under an annealing temperature ranging between approximately room temperature or 25° C. and 2040° C. for an effective duration of time.
2. The method according to claim 1 , wherein said 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 sapphire is deposited as a sapphire thin film on to said substrate.
4. The method according to claim 1 , wherein said sapphire is deposited as a doped sapphire thin film on to said substrate.
5. The method according to claim 4 , wherein the doped sapphire thin film is doped with doping element comprising one or more of chromium, chromium oxide, magnesium, magnesium oxide, beryllium, beryllium oxide, lithium, lithium oxide, sodium, sodium oxide, potassium, potassium oxide, calcium, calcium oxide, molybdenum, molybdenum oxide, tungsten, and tungsten oxide.
6. The method according to claim 5 , wherein the ratio of sapphire:doping element is in the range of 1:x, wherein x ranges from 1 to 3.
7. The method according to claim 1 , wherein a thickness of said substrate is of one or more orders of magnitude greater than a thickness of said sapphire thin film.
8. The method according to claim 7 , wherein the thickness of said sapphire thin film is about 1/1000 of the thickness of said substrate.
9. The method according to claim 7 , wherein the thickness of said sapphire thin film is between 10 nm and 1000 nm.
10. The method according to claim 7 , wherein the thickness of said sapphire thin film is between 10 nm and 100 nm.
11. The method according to claim 1 , wherein said effective duration of time is no less than 30 minutes and no more than 10 hours.
12. A method for protecting a surface of a substrate by coating said surface with sapphire using the method according to claim 1 .
13. A screen fabricated by using the method according to claim 1 for use in displays.