Method for bonding and debonding substrates

Abstract

The invention relates to a method for the temporary bonding of a product substrate with a carrier substrate and for the debonding of a product substrate from a carrier substrate, corresponding devices and a substrate stack.

Claims

1. A method of temporarily bonding a product substrate with a carrier substrate, comprising at least the following steps: producing a metallized temporary bonding layer on the product substrate and/or on the carrier substrate, thermally bonding the product substrate with the carrier substrate at the metallized temporary bonding layer, wherein structures are formed in the carrier substrate, wherein the carrier substrate comprises elevations and cavities, wherein the elevations are stably connected to the product substrate via metallic contacts, and wherein the cavities are arranged between the elevations.

2. The method according to claim 1, wherein the metallized temporary bonding layer is produced on a protective layer on the product substrate.

3. The method according to claim 1, wherein the temporary bonding layer is produced at elevations of the carrier substrate.

4. The method according to claim 1, wherein a protective layer is applied on the product substrate before the production of the metallized temporary bonding layer on the product substrate and/or on the carrier substrate.

5. A substrate stack produced using the method according to claim 1, comprising: the product substrate; and the carrier substrate, wherein the product substrate and the carrier substrate are connected by the metallized temporary bonding layer.

6. A device for temporarily bonding a product substrate with a carrier substrate, the device comprising: producing means for producing a metallized temporary bonding layer on the product substrate and/or on the carrier substrate; and bonding means for thermally bonding the product substrate with the carrier substrate at the metallized temporary bonding layer, wherein structures are formed in the carrier substrate, wherein the carrier substrate comprises elevations and cavities, wherein the elevations are stably connected to the product substrate via metallic contacts, and wherein the cavities are arranged between the elevations.

7. A method for debonding a product substrate from a carrier substrate when the product substrate and the carrier substrate are temporarily bonded according to the method of claim 1 as a substrate stack by the metallized temporary bonding layer, the method for debonding comprising at least the following steps: mounting and fixing the substrate stack on a substrate holder, focusing debonding radiation through the carrier substrate onto the metallized temporary bonding layer, thereby melting, evaporating and/or sublimating the metallized temporary bonding layer, and detaching of the product substrate from the carrier substrate.

8. The method according to claim 7, wherein a thermal conductivity of the carrier substrate lies between 0.1 W/(m*K) and 5000 W/(m*K).

9. The method according claim 7, wherein the substrate stack is heated and/or cooled by heating and/or cooling.

10. The method according to claim 7, wherein the debonding radiation is focused in a pulsed manner on the metallized temporary bonding layer.

11. The method according to claim 7, wherein an energy input of the debonding radiation into the metallized temporary bonding layer is measured, and a radiant power of the debonding radiation is controlled.

12. The method according to claim 7, wherein the melted and evaporated and/or sublimated metallized temporary bonding layer condenses and solidifies and/or re-sublimates in cavities of the carrier substrate before the detaching of the product substrate from the carrier substrate.

13. A device for debonding a product substrate from a carrier substrate, comprising: a device according to claim 1 for temporarily bonding the product substrate with the carrier substrate as a substrate stack by the metallized temporary bonding layer, the device for the temporary bonding; a substrate holder for mounting and fixing the substrate stack, a radiation source for focusing debonding radiation through the carrier substrate onto the metallized temporary bonding layer, thereby melting, evaporating and/or sublimating the metallized temporary bonding layer, and detachment means for detaching the product substrate from the carrier substrate.

14. The method according to claim 7, wherein the debonding radiation comprises a laser beam.

15. The device according to claim 13, wherein the debonding radiation comprises a laser beam.

16. The method according to claim 8, wherein the thermal conductivity of the carrier substrate lies between 1 W/(m*K) and 2500 W/(m*K).

17. The method according to claim 8, wherein the thermal conductivity of the carrier substrates lies between 0.5 W/(m*K) and 1000 W/(m*K).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages, features and details of the invention emerge from the following description of preferred examples of embodiment and with the aid of the drawings. In the latter:

(2) FIG. 1 shows a diagrammatic sketch of a substrate stack according to the invention in a first embodiment,

(3) FIG. 2 shows a diagrammatic sketch of a substrate stack according to the invention in a second embodiment during debonding, and

(4) FIG. 3a-3c show diagrammatic sketches of carrier substrates in different embodiments.

DETAILED DESCRIPTION OF THE INVENTION

(5) In the figures, identical components or components with the same function are denoted by the same reference numbers. All the sketches can be seen enlarged for purposes of representation, so that the figures do not have to show the proportions of the actual embodiments.

(6) FIG. 1 shows a diagrammatic sketch of a substrate stack 6 according to the invention. Substrate stack 6 comprises a structured carrier substrate 1, an, in particular metallic, temporary bonding layer 2, a protective layer 3 and a product substrate 4.

(7) In this embodiment, temporary bonding layer 2 is applied as a metallisation over the whole area on represented protective layer 3, which can be an atomic thin or molecular thin barrier layer.

(8) FIG. 2 represents a diagrammatic sketch of another substrate stack 6 according to the invention during debonding. In this embodiment of substrate stack 6, metallisation 2 has been applied only on elevations 1e of carrier substrate 1, so that metallisation 2 represents only targeted partial areas of the temporary bonding layer. In other words, temporary bonding layer 2 has been applied in the form of islands. Protective layer 3 separates product substrate 4 from metallic temporary bonding layer 2.

(9) A debonding beam 5 strikes at a point on temporary bonding layer 2 applied on elevation 1e through carrier substrate 1.

(10) The movement of temporary bonding layer 2 into surrounding cavities 1k of carrier substrate 1 is not represented. The convergence of debonding beam 5 symbolises both the targeted deflection of bonding beam 5 as well as the focusing.

(11) FIG. 3a represents a further embodiment according to the invention of the in particular transparent carrier substrate 1. Carrier substrate 1 comprises a multiplicity of elevations 1e, which can both support the product substrate (not represented) and also form the contact point for the temporary bonding layer (not represented).

(12) Elevations 1e can be distributed, in particular uniformly, on the carrier substrate linearly or in a grid-shaped array, in order to be able to enable uniform force absorption of the processing forces. Cavities 1k of carrier substrate 1 are located between elevations 1e.

(13) Deposits of the residues of the temporary bonding layer after the re-sublimation or the condensation and solidification are not represented.

(14) FIG. 3b represents another embodiment according to the invention of the in particular transparent carrier substrate 1. Carrier substrate 1 comprises a multiplicity of elevations 1e, which can both support the product substrate (not represented) and also form the contact point for the temporary bonding layer (not represented). In this embodiment of carrier substrate 1, elevations 1e have convex surfaces, so that point-like contacting in particular with the product substrate (not represented) is enabled. Compared to the embodiment in FIG. 3a, the effective areas of the temporary bonding layer (not represented) become smaller on account of the capillary effect of convex elevations 1e. On the one hand, a material saving can thus be achieved with the temporary bonding layer. On the other hand, effective debanding can be achieved due to the reduction in size of the support areas.

(15) FIG. 3c represents a further embodiment according to the invention of the in particular transparent carrier substrate 1.sup.IV. Carrier substrate 1.sup.IV comprises a multiplicity of elevations 1.sup.IVe, which can both support the product substrate (not represented) and also form the contact point for the temporary bonding layer (not represented). In this embodiment 1.sup.IV of the carrier substrate, elevations 1.sup.IVe are punctiform. They are surrounded by cavities 1.sup.IVk. The uniform distribution of elevations 1.sup.IVe on carrier substrate 1.sup.IV is particularly advantageous in this embodiment, wherein the percentage bearing area compared to the other embodiments 3a and 3b can turn out to be smaller.

LIST OF REFERENCE NUMBERS

(16) 1, 1, 1, 1, 1.sup.IV carrier substrate 1e, 1e, 1.sup.IVe elevations 1k, 1k, 1.sup.IVk cavities 2, 2 temporary bonding layer 3, 3 protective layer 4, 4 product substrate 5 debonding radiation 6, 6 substrate stack