Systems and methods for molecular bonding of substrates

Abstract

A method for bonding a first substrate having a first surface to a second substrate having a second surface. This method includes the steps of holding the first substrate by at least two support points, positioning the first substrate and the second substrate so that the first surface and the second surface face each other, deforming the first substrate by applying between at least one pressure point and the two support points a strain toward the second substrate, bringing the deformed first surface and the second surface into contact, and progressively releasing the strain to facilitate bonding of the substrates while minimizing or avoiding the trapping of air bubbles between the substrates.

What is claimed is: 
     
         1 . A bonding system for bonding a first substrate to a second substrate, comprising:
 at least two support elements located and configured to support a first substrate thereon such that the first substrate is unsupported between the at least two support elements;   a support device configured to support a second substrate in alignment with the first substrate when the first substrate is supported by the at least two support elements; and   at least one strain application device located and configured to contact and strain a first substrate supported by the at least two support elements at a location between the at least two support elements and deform a first substrate such that the first substrate bends toward and contacts the second substrate;   wherein the at least one strain application device is configured to progressively release the strain applied to a first substrate such that a bonding wave propagates between the first substrate and a second substrate supported on the support device response to the release of the strain applied to the first substrate.   
     
     
         2 . The bonding system of  claim 1 , wherein each support element of the at least two support elements comprises a sucker or a suction cup. 
     
     
         3 . The bonding system of  claim 1 , further comprising at least one telescopic arm attached to at least one support element of the at least two support elements. 
     
     
         4 . The bonding system of  claim 1 , wherein the at least two support elements comprise at least two spacers disposed on the support device and extending a height over the support device greater than a thickness of the second substrate. 
     
     
         5 . The bonding system of  claim 4 , wherein the at least two spacers disposed on the support device extend a height of at least 975 μm over the support device. 
     
     
         6 . The bonding system of  claim 1 , wherein the at least one strain application device comprises at least one piston rod. 
     
     
         7 . The bonding system of  claim 1 , wherein the at least one strain application device is mounted on a mobile device configured to move the at least one strain application device relative to the first substrate. 
     
     
         8 . The bonding system of  claim 7 , wherein the mobile device comprises a robot. 
     
     
         9 . The bonding system of  claim 1 , wherein the support device is configured to support a plurality of second substrates in alignment with the first substrate when the first substrate is supported by the at least two support elements. 
     
     
         10 . The bonding system of  claim 1 , wherein the strain application device is configured to contact the first substrate only at a point. 
     
     
         11 . The bonding system of  claim 1 , wherein the strain application device is configured to contact the first substrate along a line of contact. 
     
     
         12 . The bonding system of  claim 1 , wherein the support device includes a vacuum device configured to hold the second substrate against the support device by a vacuum generated by the vacuum device. 
     
     
         13 . The bonding system of  claim 12 , wherein the bonding system is configured to release the vacuum generated by the vacuum device, and to subsequently progressively release the strain applied to a first substrate held by the at least two support elements. 
     
     
         14 . The bonding system of  claim 1 , wherein the bonding system is configured to selectively control a rate at which the strain applied to a first substrate is released and the rate of propagation of the resulting bonding wave between the first substrate and a second substrate. 
     
     
         15 . A method for bonding a first substrate having a first surface to a second substrate having a second surface, which comprises:
 holding the first substrate by at least two support points;   positioning the first substrate and the second substrate so that the first surface and the second surface face each other;   deforming the first substrate by applying between at least one pressure point and the at least two support points a strain toward the second substrate;   bringing the deformed first surface and the second surface into contact; and progressively releasing the strain to facilitate bonding of the substrates.   
     
     
         16 . The method of  claim 15 , wherein the applied strain deforms the first substrate such that a central portion of the first substrate portion initially contacts the second substrate surface before the strain is released to propagate a bonding wave which bonds the substrates together. 
     
     
         17 . The method of  claim 16 , wherein the strain is applied in a linear manner so that the central portion of the first substrate contacts the second substrate in a line of contact before the strain is released to propagate a bonding wave which bonds the substrates together. 
     
     
         18 . The method of  claim 15 , wherein the first substrate is held by suckers or suction cups placed at the at least two support points. 
     
     
         19 . The method of  claim 18 , wherein each sucker or suction cup is linked to a telescopic arm. 
     
     
         21 . The method of  claim 15 , wherein the second substrate is placed on a support comprising at least two spacers located respectively on each side of the second substrate, with the spacers being thicker than the thickness of the second substrate, the first substrate being held by resting on the spacers, with the at least two support points being points of contact between the spacers and the first substrate.