Method of bonding a semiconductor wafer to a support substrate

1 . A method of bonding a semiconductor wafer to a support substrate comprising the steps of:

providing a semiconductor wafer;

coating at least part of one face of the wafer with a water soluble coating layer;

providing a double sided adhesive tape, at least one side of the adhesive tape comprising a thermal release adhesive;

adhering the double sided adhesive tape to coating layer by means of said thermal release adhesive;

adhering the reverse side of the adhesive tape to the support substrate.

2 . A method as claimed in claim 1 , wherein the semiconductor wafer is a GaAs wafer.

3 . A method as claimed in claim 1 , wherein both sides of the tape are coated with a thermal release adhesive.

4 . A method as claimed in claim 1 , wherein one side of the tape is coated with a thermal release adhesive and the opposite side is coated with a non-thermal release adhesive.

5 . A method as claimed in claim 4 , wherein the adhesive tape is Revalpha.

6 . A method as claimed in claim 1 , wherein the coating layer is a water soluble PVA solution, preferably Emulsitone.

7 . A method as claimed in claim 1 , wherein the support substrate is sapphire.

8 . A method of de-bonding a semiconductor wafer and support structure as bonded by the method of claim 1 , comprising the steps of:

heating the wafer to separate the wafer coating layer from the adhesive tape;

rinsing the wafer to remove the water soluble coating layer.

9 . A method as claimed in claim 8 , wherein the wafer is mounted to a film frame after release from the substrate.

10 . A bonded structure comprising:

a semiconductor wafer;

a wafer soluble coating layer on one side of the wafer;

a double sided adhesive tape, at least one side of which comprises a thermal release adhesive, the adhesive tape being adhered to the coating layer by means of the thermal release adhesive; and

a substrate adhered to the opposite side of the adhesive layer.

11 . A bonded structure as claimed in claim 10 , wherein the wafer is GaAs.

12 . A bonded structure as claimed in claim 10 , wherein the coating layer is PVA, preferably Emulsitone.

13 . A bonded structure as claimed in claim 10 , wherein the adhesive tape is Revalpha.