Forming front metal contact on solar cell with enhanced resistance to stress

Abstract

System and method of providing a photovoltaic (PV) cell having a cushion layer to alleviate stress impact between a front metal contact and a thin film PV layer. A cushion layer is disposed between an extraction electrode and a photovoltaic (PV) surface. The cushion layer is made of a nonconductive material and has a plurality of vias filled with a conductive material to provide electrical continuity between the bus bar and the PV layer. The cushion layer may be made of a flexible material preferably with rigidity that matches the substrate. Thus, the cushion layer can effectively protect the PV layer from physical damage due to tactile contact with the front metal contact.

What is claimed is: 
     
         1 . A method of manufacturing photovoltaic modules, said method comprising:
 attaching a front conductive layer to a cushion layer to generate a composite front layer, wherein said cushion layer is less rigid than the front conductive layer; and   attaching the composite front layer to a photovoltaic cell that is configured to convert light energy to electrical energy, wherein the cushion layer is disposed between the front conductive layer and the photovoltaic cell and configured to protect the photovoltaic cell from physical damage due to tactile contact with the front conductive layer.   
     
     
         2 . The method as described in  claim 1 , wherein the cushion layer comprises a flexible polymer material. 
     
     
         3 . The method as described in  claim 2 , wherein the flexible polymer material comprises polyethylene terephthalate (PET) combined with pressure sensitive adhesive (PSA). 
     
     
         4 . The method as described in  claim 1 , wherein the cushion layer comprises a layer of a nonconductive material, the method further comprising:
 drilling a plurality of vias through the non-conductive material of the cushion layer; and   dispensing a conductive material into the plurality of vias to form electrical contact between a front electrode of the photovoltaic cell and the front conductive layer.   
     
     
         5 . The method as described in  claim 1 , wherein the attaching of the front conductive layer to the cushion layer comprises laminating the front conductive layer with the cushion layer. 
     
     
         6 . The method as described in  claim 1 , further comprising attaching a back electrode and a substrate to a photovoltaic layer of the photovoltaic cell, wherein the back electrode is disposed between the substrate and the photovoltaic layer. 
     
     
         7 . The method as described in  claim 6 , wherein:
 the front conductive layer comprises Cu,   the substrate comprises a polymer material,   the cushion layer comprises a polymer material, and   the photovoltaic layer comprises thin film GaAs.   
     
     
         8 . The method as described in  claim 6 , wherein the photovoltaic layer is less than 10 μm in thickness and comprises a GaAs layer. 
     
     
         9 . The method as described in  claim 6 , wherein the front conductive layer is 50 μm in thickness and the photovoltaic layer is less than 10 μm in thickness. 
     
     
         10 . The method as described in  claim 1 , wherein the attaching of the front conductive layer to the cushion layer further comprises detaching a release liner bonded to the cushion layer. 
     
     
         11 . The method as described in  claim 1 , wherein the cushion layer comprises a layer of a nonconductive material, and further comprising:
 drilling a plurality of vias through the cushion layer;   dispensing a conductive material in said plurality of vias to form electrical contact between a front electrode of said photovoltaic cell and the front conductive layer.   
     
     
         12 . The method as described in  claim 1 , wherein the front metal layer is thicker than the photovoltaic layer. 
     
     
         13 . The method as described in  claim 1 , further comprising disposing an encapsulation layer on top of the front conductive layer.