Method for producing a microsystem having a thin film made of lead zirconate titanate

1. A method for producing a micro system, the method comprising:

providing a substrate made of aluminum oxide;

producing a thin film on the substrate by depositing lead zirconate titanate onto the substrate at a predefined temperature;

cooling down the substrate together with the thin film; and

increasing a value of a pyroelectric coefficient of the thin film by:

depositing the lead zirconate titanate onto the substrate with a thermal deposition method at a temperature of the substrate greater than 500° C. and maintaining a zirconium content of the lead zirconate titanate in the thin film between 40% and 50% such that the lead zirconate titanate in the thin film is self polarized and is present predominantly in a rhombohedral phase; and,

maintaining a rhombohedral form of the lead zirconate titanate as the substrate is cooled down together with the thin film.

2. The method as claimed in claim 1 , wherein the lead zirconate titanate has a pyroelectric coefficient of greater than 1.3*10 4 C/Km2.

3. The method as claimed in claim 1 , wherein the deposition method is a sputtering process or a laser ablation process.

4. The method as claimed in claim 1 , wherein the deposition method comprises a co disposition process with three individual targets for the lead, the zirconium and the titanium respectively.

5. The method as claimed in claim 1 , wherein a zirconium content of the lead zirconate titanate in the thin film is in a morphotropic phase boundary range.

6. The method as claimed in claim 1 , wherein the lead zirconate titanate is deposited in an oxygen-containing atmosphere.

7. The method as claimed in claim 1 , wherein the substrate has a top side comprising a layer of platinum, onto which the lead zirconate titanate is deposited.

8. The method as claimed in claim 1 , wherein the substrate material is sapphire.

9. The method as claimed in claim 1 , wherein the substrate has a top side that is polished, and the thin film is deposited on the polished top side.

10. An infrared light sensor chip with a micro system, comprising:

an aluminum oxide substrate; and

a lead zirconate titanate thin firm deposited on the substrate;

said lead zirconate titanate being self-polarized and being present predominantly in a rhombohedral phase; and,

said lead zirconate titanate having a zirconium content between 40% and 50% which increases a value of a pyroelectric coefficient of the thin film.

11. The infrared light sensor chip as claimed in claim 10 , wherein the lead zirconate titanate has a pyroelectric coefficient of greater than 1.3*10 4 C/Km2.

12. The infrared light sensor chip as claimed in claim 10 , wherein the substrate comprises a sapphire material.

13. A method for producing a micro system, the method comprising:

providing a substrate made of aluminum oxide;

producing a thin film on the substrate by:

depositing the lead zirconate titanate onto the substrate with a thermal deposition method;

maintaining a temperature of the substrate at a value greater than 500° C. as the lead zirconate titanate is deposited onto the substrate such that the lead zirconate titanate in the thin film is self polarized and is present predominantly in a rhombohedral phase; and,

cooling down the substrate together with the thin film.

14. The method as claimed in claim 13 , wherein the lead zirconate titanate has a pyroelectric coefficient of greater than 1.3*10 4 C/Km2.

15. The method as claimed in claim 13 , wherein a zirconium content of the lead zirconate titanate is between 40% and 50%.

16. The method as claimed in claim 13 , wherein the substrate comprises a sapphire material.