A debonder apparatus for debonding a temporary bonded wafer pair comprising a first wafer bonded to a second wafer at a bonding interface, said debonder apparatus comprising: an upper chuck and a lower chuck having an upper surface oriented parallel and opposite to the lower surface of the upper chuck ; means for holding an unbonded surface of the first wafer of the temporary bonded wafer pair onto the lower surface of the upper chuck ; means for initiating a separation front at a point of the bonding interface of the temporary bonded wafer pair ; and means for holding the unbonded surface of the separated second wafer onto the upper surface of the lower chuck ; characterized in that the debonder apparatus comprises a clam-shell type reactor comprising first and second isolated chambers; that the upper chuck is contained within the first chamber and comprising a lower surface protruding into the second chamber and an edge configured to be held in fixed position via clamping means ; that the lower chuck is contained within the second chamber ; that the debonder apparatus comprises means for pressurizing the first chamber and wherein said first chamber pressurizing means applies pressure onto an upper surface of the upper chuck while the upper chuck edge is held in fixed position via the clamping means ; and thereby causes the lower surface of the upper chuck and the attached wafer pair to bow downward; and that the debonder apparatus comprises means for pressurizing the second chamber while the first chamber pressure is reduced thereby causing removal of the downward bowing of the upper chuck and the attached wafer pair and propagation of the separation front through the entire bond interface. an upper chuck and a lower chuck having an upper surface oriented parallel and opposite to the lower surface of the upper chuck ; means for holding an unbonded surface of the first wafer of the temporary bonded wafer pair onto the lower surface of the upper chuck ; means for initiating a separation front at a point of the bonding interface of the temporary bonded wafer pair ; and means for holding the unbonded surface of the separated second wafer onto the upper surface of the lower chuck ; characterized in that the debonder apparatus comprises a clam-shell type reactor comprising first and second isolated chambers; that the upper chuck is contained within the first chamber and comprising a lower surface protruding into the second chamber and an edge configured to be held in fixed position via clamping means ; that the lower chuck is contained within the second chamber ; that the debonder apparatus comprises means for pressurizing the first chamber and wherein said first chamber pressurizing means applies pressure onto an upper surface of the upper chuck while the upper chuck edge is held in fixed position via the clamping means ; and thereby causes the lower surface of the upper chuck and the attached wafer pair to bow downward; and that the debonder apparatus comprises means for pressurizing the second chamber while the first chamber pressure is reduced thereby causing removal of the downward bowing of the upper chuck and the attached wafer pair and propagation of the separation front through the entire bond interface. <EOS>