Non-light-emitting variable transmission device and a method of forming the same

Abstract

A non-light-emitting variable transmission device can include an active stack; a transparent conductive layer overlying the active stack; an antireflective layer overlying the transparent conductive layer and defining a hole; and a bus bar comprising a conductive tape that extends into the hole and contacts the transparent conductive layer. Proper selection of materials and design of a bus bar can allow an electrical connection to be made to the transparent conductive layer without the need to cut an underlying transparent conductive layer. A method of forming the non-light-emitting variable transmission device can include patterning the antireflective layer to define the hole that extends to the transparent conductive layer. Improved control in patterning allows the antireflective layer to be relatively thin and not remove too much of the underlying transparent conductive layer.

1 . A non-light-emitting variable transmission device, comprising:
 an active stack comprising an electroactive material;   an intermediate layer defining a first hole;   a first conductive layer between the active stack and the intermediate layer;   a first bus bar comprising a first conductive tape that extends into the first hole and contacts the first conductive layer.   
     
     
         2 . The non-light-emitting variable transmission device of  claim 1 , wherein the first bus bar comprises a first backing substrate and a first adhesive layer. 
     
     
         3 . The non-light-emitting variable transmission device of  claim 2 , wherein the first bus bar extends into the first hole and contacts the first conductive layer. 
     
     
         4 . The non-light-emitting variable transmission device of  claim 3 , wherein both the first backing substrate and the first adhesive layer extend above the intermediate layer. 
     
     
         5 . The non-light-emitting variable transmission device of  claim 4 , wherein only the first adhesive layer extends into the first hole. 
     
     
         6 . The non-light-emitting variable transmission device of  claim 5 , wherein the first adhesive layer comprises conductive material. 
     
     
         7 . The non-light-emitting variable transmission device of  claim 6 , wherein the conductive material does not contain silver. 
     
     
         8 . The non-light-emitting variable transmission device of  claim 1 , further comprising a second bus bar extending into a second hole of the intermediate layer contacting a second conductive layer. 
     
     
         9 . The non-light-emitting variable transmission device of  claim 8 , wherein each of the first bus bar and the second bus bar extend above the intermediate layer. 
     
     
         10 . The non-light-emitting variable transmission device of  claim 1 , further comprising a substrate, wherein the active stack is between the intermediate layer and the substrate. 
     
     
         11 . The non-light-emitting variable transmission device of  claim 1 , further comprising a second conductive layer, wherein the active stack is between the first conductive layer and the second conductive layer. 
     
     
         12 . The non-light-emitting variable transmission device of  claim 9 , wherein the first bus bar does not contact any layer of the active stack or the second conductive layer. 
     
     
         13 . The non-light-emitting variable transmission device of  claim 8 , further comprising a third hole between the first hole and the second hole to electrically isolate the first bus bar. 
     
     
         14 . The non-light-emitting variable transmission device of  claim 2 , wherein the backing substrate of the first bus bar has a resistivity in a range of 1 μΩ-cm to 7 μΩ-cm. 
     
     
         15 . The non-light-emitting variable transmission device of  claim 11 , wherein the first bus bar does not contact the second conductive layer.