Method of clearing electrical contact pads in thin film sealed OLED devices

Abstract

A process of cleaning wire bond pads associated with OLED devices, including the steps of depositing on the wire bond pads one or more layers of ablatable material, and ablating the one or more layers with a laser, thereby exposing a clean wire bond pad.

What is claimed is: 
     
       1. A process of cleaning wire bond pads associated with OLED devices formed on a substrate using a shadow mask wherein the shadow mask has openings adapted to align with the active matrix display region and the wire bond pad region, the method comprising the steps of (a) depositing a conductive layer on a substrate; (b) placing the shadow mask over the conductive layer; (c) depositing an organic material layer on the conductive layer through the openings in the shadow mask to form an OLED pattern on the conductive layer in the active matrix display region and cover the wire bond pad region; (d) removing the shadow mask; forming a thin film encapsulation layer over substantially the entire surface of the wafer; and applying a laser beam to the wire bond pad region of the wafer so as to remove the organic material and all layers above same to expose the wire bond pads. 
     
     
       2. The process of claim 1, further comprising forming one or more additional thin film encapsulation layers over the organic material layer. 
     
     
       3. The process of claim 2, wherein the one or more additional thin film encapsulation layers comprise at least one layer composed of inorganic material. 
     
     
       4. The process of claim 2, wherein the one of more additional thin film encapsulation layers comprise at least one layer composed of organic material. 
     
     
       5. The process of claim 2, wherein the one or more additional thin film encapsulation layers comprise a first polymer layer, a second polymer layer, and a layer of inorganic material disposed between the first polymer layer and the second polymer layer. 
     
     
       6. A process of cleaning wire bond pads associated with OLED devices formed on a substrate using a shadow mask wherein the shadow mask has openings adapted to align with the active matrix display region and the wire bond pad region, the process comprising:
 depositing a conductive layer on a substrate;   placing the shadow mask over the conductive layer;   depositing an organic material layer on the conductive layer through the openings in the shadow mask to cover the active matrix display region and the wire bond pad region;   removing the shadow mask;   forming one or more encapsulation layers over substantially the entire surface of the wafer; and   applying a laser beam to the wire bond pad region of the wafer so as to remove the organic material and all layers above same to expose the wire bond pads.   
     
     
       7. The process of claim 6, wherein the one or more encapsulation layers comprises one or more thin film encapsulation layers. 
     
     
       8. The process of claim 7, wherein the one or more thin film encapsulation layers comprise at least one layer composed of inorganic material. 
     
     
       9. The process of claim 7, wherein the one of more thin film encapsulation layers comprise at least one layer composed of organic material. 
     
     
       10. The process of claim 6, wherein the one or more encapsulation layers comprise a first polymer layer, a second polymer layer, and a layer of inorganic material disposed between the first polymer layer and the second polymer layer. 
     
     
       11. A process for forming an OLED device, the process comprising:
 forming a conductive layer over a substrate, the conductive layer comprising a wire bond pad region and an active matrix display region;   positioning a shadow mask over the conductive layer, the shadow mask having first opening and a second opening, the first opening corresponding to the wire bond pad region and the second opening corresponding to the active display matrix region;   depositing an organic material through the first and second openings of the shadow mask to form an organic material layer over the wire bond pad region and the active matrix display region;   forming one or more layers over the organic material layer; and   applying a directed energy source to the wire bond pad region to remove the organic material layer and all layers above the organic material layer.   
     
     
       12. The process of claim 11, wherein the one or more encapsulation layers comprises one or more thin film encapsulation layers.