Method for producing functional device and apparatus for producing functional device

1. A method of producing a functional device, the method comprising:

imprinting a functional solid material precursor layer obtained from a functional solid material precursor solution as a starting material, the functional solid material precursor layer obtained from the functional solid material precursor solution by baking the functional solid material precursor solution at a preliminary baking temperature in a range from 80° C. to 250° C., wherein a first temperature of a heat source for supplying heat to the functional solid material precursor layer is higher than a second temperature of the functional solid material precursor layer in at least part of a time period while a mold for forming an imprinted structure is pressed against the functional solid material precursor layer;

increasing the first temperature during at least a portion of the time period while the mold is pressed against the functional solid material precursor layer;

forming, after the imprinting step, a functional solid material layer from the functional solid material precursor layer by heat treating the functional solid material precursor layer at a third temperature higher than the first temperature in an atmosphere containing oxygen; and

causing a difference in temperature between the mold and a base upon which a substrate including the functional solid material precursor layer is mounted.

2. The method of producing a functional device according to claim 1 , wherein

the heat source includes a heater for heating the mold.

3. The method of producing a functional device according to claim 1 , wherein

the part of the time period corresponds to at least 20 when the mold is pressed for the time period corresponding to 100.

4. The method of producing a functional device according to claim 1 , wherein

the first temperature is higher than the preliminary baking temperature and is in a range from 90° C. to 300° C.

5. The method of producing a functional device according to claim 1 , wherein

the preliminary baking temperature in a preliminary baking step of forming the functional solid material precursor layer is lower than a boiling point of a solvent of the functional solid material precursor solution, and

the first temperature is higher than the boiling point of the solvent.

6. The method of producing a functional device according to claim 1 , wherein

the imprinting step is executed by applying a pressure in a range from 1 MPa to 20 MPa.

7. The method of producing a functional device according to claim 1 , wherein

the imprinting step includes at least one of a mold separation process from a surface of the functional solid material precursor layer and a mold separation process from an imprinting surface of the mold, and then imprinting the functional solid material precursor layer.

8. The method of producing a functional device according to claim 1 , further comprising:

between the imprinting step and the functional solid material layer formation step, a step of entirely etching the functional solid material precursor layer under a condition where the functional solid material precursor layer is removed in a thinnest region in the imprinted functional solid material precursor layer.

9. The method of producing a functional device according to claim 1 , wherein

the functional device is a thin film transistor, and

the functional solid material layer serves as at least one selected from the group consisting of a gate electrode layer, a gate insulating layer, a source layer, a drain layer, and a channel layer in the thin film transistor.

10. The method of producing a functional device according to claim 1 , wherein

the functional device is a memory transistor, and

the functional solid material layer serves as at least one selected from the group consisting of a gate electrode layer, a ferroelectric layer, a source layer, a drain layer, and a channel layer in the memory transistor.

11. The method of producing a functional device according to claim 1 , wherein

the functional device is a capacitor, and

the functional solid material layer serves as a dielectric layer and/or an electrode layer.

12. The method of producing a functional device according to claim 1 , wherein

the functional device is an actuator including a piezoelectric layer, and

the functional solid material layer serves as the piezoelectric layer.

13. The method of producing a functional device according to claim 1 , wherein

the functional device is an optical device including a base material provided thereon with a plurality of latticed layers, and

the functional solid material layer serves as the latticed layer.

14. The method of producing a functional device according to claim 1 , wherein

the heat source includes a heater for heating the base.

15. The method of producing a functional device according to claim 14 , wherein

the mold is higher in temperature than the base by at least 10° C.

16. The method of producing a functional device according to claim 1 , wherein

the functional solid material precursor solution includes at least one selected from the group consisting of:

a solution containing metal alkoxide;

a solution containing a metal organic acid salt;

a solution containing a metal inorganic acid salt;

a solution containing metal halide;

a solution including an inorganic compound containing metal, nitrogen, and hydrogen; and

a solution containing metal hydride.

17. The method of producing a functional device according to claim 16 , wherein

the functional solid material precursor solution includes at least one selected from the group consisting of the solution containing metal alkoxide, the solution containing a metal organic acid salt, and the solution containing a metal inorganic acid salt, and

in the imprinting step, the functional solid material precursor layer is transformed into the functional solid material layer at a volume shrinkage factor in a range from 20% to 80%.

18. The method of producing a functional device according to claim 16 , wherein

the functional solid material precursor solution includes at least one selected from the group consisting of:

the solution containing metal halide;

the solution including an inorganic compound containing metal, nitrogen, and hydrogen; and

the solution containing metal hydride; and

in the functional solid material layer formation step, the functional solid material precursor layer is transformed into the functional solid material layer at a volume shrinkage factor in a range from 1% to 30%.