Interlayer of sub-structure having elevations and further sub-structure with filler particles in recesses between the elevations

1. A structure, comprising:

a first sub-structure; and

a second sub-structure coupled with the first sub-structure and being a composite comprising filler particles in a matrix,

wherein a surface of the first sub-structure has a surface profile with first elevations and first recesses configured to enable at least part of the filler particles to at least partially enter the first recesses to thereby form an interlayer comprising the first elevations of the first sub-structure and filler particles in the matrix of the second sub-structure,

wherein the surface of the first sub-structure has second elevations and second recesses formed on the first elevations and the first recesses,

wherein the second recesses are dimensioned to enable at least part of the matrix to at least partially enter the second recesses and are dimensioned to disable the filler particles to enter the second recesses.

2. The structure of claim 1 , wherein the first elevations and the first recesses have a depth in a range from 0.1 μm to 50 μm.

3. The structure of claim 1 , wherein at least part of the filler particles have a diameter in a range from 10 nm to 10 μm.

4. The structure of claim 1 , wherein a ratio between a depth of the first elevations and a distance between top peaks of adjacent first elevations is in a range from 0.2 to 5.

5. The structure of claim 1 , wherein the second elevations and the second recesses have a depth in a range from 1 nm to 100 nm.

6. The structure of claim 1 , wherein the first sub-structure comprises a base body on which the first elevations are formed.

7. The structure of claim 6 , wherein:

the base body and the first elevations are made of the same material; and/or

the base body and the first elevations are in direct physical contact with each other.

8. The structure of claim 6 , further comprising:

an intermediate layer between the base body and the first elevations.

9. The structure of claim 8 , wherein at least one undercut is formed between the base body and the first elevations, wherein the at least one undercut is formed to promote mechanical interlocking and thereby adhesion within the interlayer and/or the at least one undercut corresponds to a pore geometry with a side angle smaller than 90°.

10. The structure of claim 8 , wherein the filler particles have a value of the coefficient of thermal expansion which is selected so that the presence of the filler particles in the interlayer reduces a mismatch between the coefficients of thermal expansion between the first sub-structure and the second sub-structure.

11. The structure of claim 1 , wherein the second elevations and the second recesses are configured as a porous adhesion promoter.

12. The structure of claim 1 , wherein at least one of the first elevations and the second elevations are arranged in a random fashion over a continuous surface area.

13. A package, comprising:

at least one functional package body;

an encapsulant encapsulating at least part of the at least one functional package body; and

the structure of claim 1 , the structure being formed as an interface between the encapsulant and at least part of the at least one functional package body,

wherein the first sub-structure forms part of the at least one functional package body and the second sub-structure forms at least part of the encapsulant.

14. The package of claim 13 , wherein the at least one functional package body comprises at least one of a carrier configured to carry an electronic component, an electronic component, and an electrically conductive contact element configured to electrically couple an electronic component with a carrier.

15. The package of claim 13 , wherein:

the structure is formed as an interface between the encapsulant and a metallic surface of the at least one functional package body; and/or

the package is a power module.