Device and method for bonding of two substrates

1. A device for bonding a first substrate surface of a first substrate to a second substrate surface of a second substrate, said device comprising:

a first substrate holder for accommodating the first substrate;

a second substrate holder for accommodating the second substrate;

wherein at least the first substrate holder has a first recess with a fixing device for fixing the first substrate in the first recess, and an elevation at least partly surrounding the first recess, said elevation having an expansion surface for expansion of the first substrate surface,

wherein the first recess and/or the elevation is/are adapted to a shape of the first substrate, such that the first substrate surface together with the expansion surface forms a substantially continuous surface and/or merges into the elevation,

wherein a first distance between a periphery of the first substrate and an interior wall of the elevation is less than 1 mm, and

wherein a second distance between the first substrate surface and the expansion surface is less than 1 mm.

2. The device according to claim 1 , wherein said expansion surface provides seamless expansion of the first substrate surface.

3. The device according to claim 1 , wherein the first recess and/or the elevation are adaptable manually and/or semi-automatically and/or automatically such that the first substrate surface forms the substantially continuous surface with the expansion surface and/or merges into the elevation.

4. The device according to claim 1 , wherein the first substrate holder has an outer component and an inner component movable in the outer component, wherein the outer component and/or inner component is translationally and/or rotatably movable, wherein the inner and outer components are fixable to each other.

5. The device according to claim 4 , wherein the device has at least one hole for evacuating and/or rinsing the first recess in the inner component.

6. The device according to claim 4 , wherein the device has a plurality of holes for evacuating and/or rinsing the first recess, said plurality of holes arranged in a symmetrically distributed manner in the inner component.

7. The device according to claim 1 , wherein the second distance between the first substrate surface and the expansion surface is adjustable.

8. The device according to claim 1 , wherein the expansion surface of the elevation has an inwardly and/or outwardly curved surface.

9. The device according to claim 1 , wherein the expansion surface of the elevation has an inwardly and/or outwardly bevelled surface at an angle (a).

10. A system comprised of a device according to claim 1 and the first substrate, wherein the first substrate surface merges into the elevation.

11. A method for bonding a first substrate surface of a first substrate to a second substrate surface of a second substrate by means of the device according to claim 1 , wherein a gas arranged between the first and second substrate surfaces during the bonding process is displaced from a centre of the first and second substrates to an edge of the first and second substrates,

wherein at least the first substrate surface merges into the elevation such that expansion of the gas only takes place outside the first and second substrates.