SEMICONDUCTOR THIN FILM STRUCTURE AND METHOD OF FORMING THE SAME

• US 20140070372A1
• Filed: 05/15/2012
• Published: 03/13/2014
• Est. Priority Date: 05/20/2011
• Status: Active Grant

• Current Assignee: Hexasolution Co., Ltd.
• Original Assignee: Seoul National University R&DB Foundation (Seoul National University)
• Inventors: Yoon, Euijoon, Ha, Shin-Woo
• Granted Patent: US 9,793,359 B2
• Time in Patent Office: Days
• US Class Current: 257/615
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/02658 Pretreatments cleaning in general H01L21/02041
• CPC Class Codes: H01L 21/02664 Aftertreatments planarisation in general H01L21/304
• CPC Class Codes: H01L 29/0657 characterised by the shape of the body
• CPC Class Codes: H01L 29/2003 Nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate

Abstract

A method of forming a semiconductor thin film structure and a semiconductor thin film structure formed using the same is provided. A sacrificial layer is formed on a substrate and then patterned through various methods, an inorganic thin film is formed on the sacrificial layer and then the sacrificial layer is selectively removed to form a cavity defined by the substrate and the inorganic thin film on the substrate.

Claims

1. A semiconductor thin film structure comprising:

a substrate; and

an inorganic thin film formed on the substrate to define a plurality of cavities between the substrate and the inorganic thin film such that the plurality of cavities separated from each other have a controlled shape, size and 2-dimensional arrangement.

2. The semiconductor thin film structure of claim 1, further comprising a nitride semiconductor thin film formed on the substrate.

3. The semiconductor thin film structure of claim 2, wherein the nitride semiconductor thin film has a structure of at least two-layered films.

4. The semiconductor thin film structure of claim 3, further comprising another inorganic thin film formed between the at least two-layered films to define a plurality of other cavities between the at least two-layered films such that the plurality of other cavities separated from each other have a controlled shape, size and 2-dimensional arrangement.

5. The semiconductor thin film structure of claim 2, wherein a coefficient of thermal expansion of the substrate is greater than that of the nitride semiconductor thin film, and the plurality of cavities are compressed toward a surface direction by the nitride semiconductor thin film.

6. The semiconductor thin film structure of claim 2, wherein a coefficient of thermal expansion of the substrate is less than that of the nitride semiconductor thin film, and the plurality of cavities are tensed toward a surface direction due to the nitride semiconductor thin film.

7. The semiconductor thin film structure of claim 1, wherein the plurality of cavities are uniformly defined as the same pattern over the substrate.

8. The semiconductor thin film structure of claim 1, wherein the plurality of cavities are defined as different patterns locally on the substrate.

30. The semiconductor thin film structure of claim 2, wherein the plurality of cavities are uniformly defined as the same pattern over the substrate.

31. The semiconductor thin film structure of claim 2, wherein the plurality of cavities are defined as different patterns locally on the substrate.

9. A method of forming a semiconductor thin film structure, comprising:

forming sacrificial layer patterns on a substrate;

forming an inorganic thin film on the sacrificial layer patterns; and

removing the sacrificial layer patterns from the substrate having the inorganic thin film formed thereon to form a plurality of cavities which are defined by the substrate and the inorganic thin film and are separated from each other.

10. The method of claim 9, further comprising forming a nitride semiconductor thin film on the substrate.

11. The method of claim 10, wherein forming the nitride semiconductor thin film is performed using portions of the substrate in which the plurality of cavities are absent as a seed through an epitaxial lateral overgrowth (ELO) method.

12. The method of claim 11, wherein the inorganic thin film has a different material from the substrate, and

further comprising patterning the inorganic thin film to expose the portions of the substrate in which the plurality of cavities are absent.

13. The method of claim 10, wherein a coefficient of thermal expansion of the substrate is greater than that of the nitride semiconductor thin film, and the plurality of cavities are compressed toward a surface direction by the nitride semiconductor thin film to reduce warpage of the substrate while the nitride semiconductor thin film is cooled after forming the nitride semiconductor thin film.

14. The method of claim 10, wherein a coefficient of thermal expansion of the substrate is less than that of the nitride semiconductor thin film, and the plurality of cavities are tensed toward a surface direction the nitride semiconductor thin film to reduce warpage of the substrate while the nitride semiconductor thin film is cooled after forming the nitride semiconductor thin film.

15. The method of claim 10, wherein at least one of a shape, size and 2-dimensional arrangement of the plurality of cavities is adjusted to adjust at least one of stress applied to the nitride semiconductor thin film, a light extraction amount from the nitride semiconductor thin film and an emission pattern.

16. The method of claim 9, wherein forming the sacrificial layer patterns comprises coating a photoresist layer on the substrate and performing a photolithography method on the photoresist layer.

17. The method of claim 9, wherein forming the sacrificial layer patterns comprises coating a resin for nanoimprint on the substrate and performing a nanoimprint method on the resin.

18. The method of claim 9, wherein forming the sacrificial layer patterns comprises forming the sacrificial layer patterns by attaching organic nanoparticles on the substrate.

19. The method of claim 9, wherein a thickness of each of the sacrificial layer patterns is in a range of about 0.01 μ

m to 10 μ

m, and a width of each of the sacrificial layer patterns is in a range of 0.01 μ

m to 10 μ

m.

20. The method of claim 9, wherein forming the inorganic thin film is performed in a temperature range in which the sacrificial layer patterns are not transformed.

21. The method of claim 9, wherein the inorganic thin film includes at least one of silica (SiO2), alumina (Al2O3), titania (TiO2), zirconia (ZrO2), yttria (Y2O3)-zirconia (ZrO2), copper oxide (CuO, Cu2O) and tantalum oxide (Ta2O5).

22. The method of claim 10, wherein at least one of composition, strength and thickness of the inorganic thin film is adjusted to adjust stress applied to the nitride semiconductor thin film.

23. The method of claim 9, wherein a shape, size and 2-dimensional arrangement of the sacrificial layer patterns are predetermined to define the plurality of cavities to have a controlled shape, size and 2-dimensional arrangement.

24. The method of claim 9, wherein a shape of the sacrificial layer patterns is adjusted to adjust a shape of the plurality of cavities.

25. The method of claim 9, further comprising reflowing the sacrificial layer patterns in order to transform a shape of the sacrificial layer patterns.

26. The method of claim 9, wherein the sacrificial layer patterns are uniformly formed in the same pattern all over the substrate.

27. The method of claim 9, wherein the sacrificial layer patterns are formed in different patterns locally on the substrate.

28. The method of claim 9, wherein removing the sacrificial layer patterns is performed using at least one of heating, a chemical reaction with gas including oxygen and a chemical reaction with a solvent.

29. A semiconductor device including a semiconductor thin film structure, comprising:

a substrate;

an inorganic thin film formed on the substrate to define a plurality of cavities between the substrate and the inorganic thin film such that the plurality of cavities separated from each other have a controlled shape, size and 2-dimensional arrangement; and

a nitride semiconductor thin film formed on the substrate.