PATENT DOCUMENT

Publication Number: US-11099703-B1
Application Number: US-201916681796-A
Country: US
Kind Code: B1

Title: Touch sensor panels with silver nanowire-based touch electrodes

Abstract:
A touch sensor panel can include a silver nanowire touch electrodes formed in a silver nanowire layer on the substrate. In some examples, the touch sensor panel can include one or more anticorrosion layers to protect silver nanowire layer from ionization. In some examples, the silver nanowires include electrochemically stable outer shells that protect the silver nanowires from ionization. Additionally or alternatively, the touch sensor panel can including one or more anti-static layers to protect against electrostatic discharge (ESD). Additionally or alternatively, one or more anticorrosion layers and/or one or more antistatic layers can be formed with a passivation layer therebetween. The passivation layer, one or more anticorrosion layers and/or one or more antistatic layers can then be laminated to the silver nanowire layer to prevent corrosion and/or ESD events in the silver nanowire layer during the fabrication of the touch sensor panel.

Claims:
The invention claimed is: 
     
       1. A touch sensor panel comprising:
 a substrate; 
 a silver nanowire layer disposed on the substrate, wherein one or more touch electrodes of the touch sensor panel are formed from silver nanowires in the silver nanowire layer; and 
 a multi-layer protective film disposed on the silver nanowire layer, wherein the multi-layer protective film comprising an antistatic layer, a passivation layer, and an anticorrosion layer, wherein the anticorrosion layer is distinct from and directly contacts the passivation layer and the passivation layer directly contacts the antistatic layer, and wherein the multi-layer protective film is coupled to the silver nanowire layer such that the anticorrosion layer is closer to the silver nanowire layer than the passivation layer and the antistatic layer. 
 
     
     
       2. The touch sensor panel of  claim 1 , wherein the passivation layer is an organic passivation layer. 
     
     
       3. The touch sensor panel of  claim 1 , wherein the passivation layer includes photoinitiators. 
     
     
       4. The touch sensor panel of  claim 1 , wherein the multi-layer protective film is photo-patternable. 
     
     
       5. The touch sensor panel of  claim 1 , wherein the multi-layer protective film is formed by wet coating and drying an antistatic material on a carrier to form the antistatic layer, by wet coating and drying passivation material on the antistatic layer to form the passivation layer, and by wet coating and drying anticorrosion material on the passivation layer to form the anticorrosion layer. 
     
     
       6. The touch sensor panel of  claim 1 , wherein the silver nanowire layer comprises silver nanowires with electrochemically stable outer shells. 
     
     
       7. The touch sensor panel of  claim 1 , further comprising:
 one or more overcoat layers comprising anticorrosion compounds disposed on and in contact with the silver nanowire layer. 
 
     
     
       8. A method of forming a touch sensor panel comprising:
 forming a silver nanowire layer on a substrate; 
 forming one or more touch electrodes of the touch sensor panel from silver nanowires in the silver nanowire layer; 
 forming a multi-layer protective film, wherein the multi-layer protective film comprising an antistatic layer, a passivation layer, and an anticorrosion layer; and 
 laminating the multi-layer protective film and the silver nanowire layer such that the anticorrosion layer is closer to the silver nanowire layer than the passivation layer and the antistatic layer. 
 
     
     
       9. The method of  claim 8 , forming the multi-layer protective film comprises:
 wet coating and drying an antistatic material on a carrier to form the antistatic layer; 
 wet coating and drying passivation material on the antistatic layer to form the passivation layer; and 
 wet coating and drying anticorrosion material on the passivation layer to form the anticorrosion layer. 
 
     
     
       10. The method of  claim 8 , wherein laminating the multi-layer protective film and the silver nanowire layer comprises lamination at an elevated temperature between 75-100° C. 
     
     
       11. The method of  claim 8 , wherein laminating the multi-layer protective film and the silver nanowire layer comprises laminating the anticorrosion layer of the multi-layer protective film to the silver nanowire layer. 
     
     
       12. The method of  claim 8 , wherein the passivation layer is an organic passivation layer. 
     
     
       13. The method of  claim 8 , wherein the multi-layer protective film is photo-patternable, and the method further comprises:
 patterning the multi-layer protective film using a photolithography process. 
 
     
     
       14. The method of  claim 8 , wherein the antistatic layer is further from the silver nanowire layer than the passivation layer or the anticorrosion layer. 
     
     
       15. A touch sensor panel comprising:
 a substrate; 
 a silver nanowire layer disposed on the substrate, wherein one or more touch electrodes of the touch sensor panel are formed from silver nanowires in the silver nanowire layer; 
 one or more overcoat layers comprising anticorrosion compounds disposed on and in contact with the silver nanowire layer; and 
 a multi-layer protective film disposed on the silver nanowire layer, wherein the multi-layer protective film comprising an antistatic layer, a passivation layer, and an anticorrosion layer, wherein the anticorrosion layer is distinct from and directly contacts the passivation layer and the passivation layer directly contacts the antistatic layer, and wherein the multi-layer protective film is coupled to the silver nanowire layer such that the anticorrosion layer is closer to the silver nanowire layer than the passivation layer and the antistatic layer. 
 
     
     
       16. The touch sensor panel of  claim 15 , wherein the one or more overcoat layers include a first overcoat layer on a first side of the sliver nanowire layer and a second overcoat layer on a second side of the silver nanowire layer opposite the first side of the silver nanowire layer. 
     
     
       17. The touch sensor panel of  claim 15 , further comprising:
 an anticorrosion film disposed on at least one of the one or more overcoat layers and contacting a third side of the silver nanowire layer perpendicular to the first side and the second side of the silver nanowire layer and contacting the substrate. 
 
     
     
       18. The touch sensor panel of  claim 17 , further comprising:
 a second passivation layer disposed on the anticorrosion film, wherein the multi-layer protective film is disposed on the second passivation layer. 
 
     
     
       19. The touch sensor panel of  claim 6 , wherein the electrochemically stable outer shells comprise nickel, palladium or platinum. 
     
     
       20. The touch sensor panel of  claim 1 , wherein the antistatic layer comprises polystyrene sulfonate.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims benefit of U.S. Provisional Application No. 62/760,012, filed Nov. 12, 2018, the disclosure of which is incorporated herein by reference. 
    
    
     FIELD OF THE DISCLOSURE 
     This relates generally to touch sensor panels, and more particularly to touch sensor panel designs that include touch electrodes formed of silver nanowire materials. 
     BACKGROUND OF THE DISCLOSURE 
     Many types of input devices are presently available for performing operations in a computing system, such as buttons or keys, mice, trackballs, joysticks, touch sensor panels, touch screens and the like. Touch screens, in particular, are popular because of their ease and versatility of operation as well as their declining price. Touch screens can include a touch sensor panel, which can be a clear panel with a touch-sensitive surface, and a display device such as a liquid crystal display (LCD), light emitting diode (LED) display or organic light emitting diode (OLED) display that can be positioned partially or fully behind the panel so that the touch-sensitive surface can cover at least a portion of the viewable area of the display device. Touch screens can allow a user to perform various functions by touching the touch sensor panel using a finger, stylus or other object at a location often dictated by a user interface (UI) being displayed by the display device. In general, touch screens can recognize a touch and the position of the touch on the touch sensor panel, and the computing system can then interpret the touch in accordance with the display appearing at the time of the touch, and thereafter can perform one or more actions based on the touch. In the case of some touch sensing systems, a physical touch on the display is not needed to detect a touch. For example, in some capacitive-type touch sensing systems, fringing electrical fields used to detect touch can extend beyond the surface of the display, and objects approaching near the surface may be detected near the surface without actually touching the surface. 
     Capacitive touch sensor panels can be formed by a matrix of partially or fully transparent or non-transparent conductive plates (e.g., touch electrodes) made of materials such as Indium Tin Oxide (ITO). In some examples, the conductive plates can be formed from other materials including conductive polymers, metal mesh, graphene, nanowires (e.g., silver nanowires) or nanotubes (e.g., carbon nanotubes). It is due in part to their substantial transparency that some capacitive touch sensor panels can be overlaid on a display to form a touch screen, as described above. Some touch screens can be formed by at least partially integrating touch sensing circuitry into a display pixel stackup (i.e., the stacked material layers forming the display pixels). 
     SUMMARY OF THE DISCLOSURE 
     This disclosure relates touch sensor stackups including silver nanowire (or other suitable conductors). In some examples, one or more anticorrosion layers can be used to protect silver nanowire materials used to form touch electrodes on a touch sensor panel from ionization (to reduce migration of ionic compounds that may cause corrosion of the touch electrodes). In some examples, the touch sensor panel stackups include one or more overcoat layers (e.g., on one or both sides) of the silver nanowire layer. The one or more of the overcoat layers can include anticorrosion compounds that protect the silver nanowire layer from ionization. In some examples, the touch sensor panel stackup can include a passivation layer that includes anticorrosion compounds (e.g., embedded in the passivation layer or deposited as anticorrosion layer on the passivation layer) that protect the silver nanowire layer from ionization (e.g., including protecting the sidewalls of the silver nanowire layer that may be exposed during photo-lithography). In some examples, the silver nanowire layer includes silver nanowires that include electrochemically stable (e.g., electrocatalytic activity less than a threshold) outer shells that protect the silver nanowires from ionization (e.g., in the ionic solutions that may be present during manufacture). 
     Additionally or alternatively, the touch sensor stackup can including one or more anti-static layers to protect against electrostatic discharge (ESD) during manufacturing or during layer use. For example, silver nanowires can be susceptible to ESD due to its nanostructure, which may nanowires with diameters less than 50 nm that may be damaged due to concentrated Joule heating during an ESD event. The one or more anti-static layers can dissipate ESD charge before the ESD charge builds up at the silver nanowire layer. 
     Additionally or alternatively, one or more anticorrosion layers and/or one or more antistatic layers can be formed with a passivation layer therebetween in one or more processes. The passivation layer, one or more anticorrosion layers and/or one or more antistatic layers can then be laminated to the silver nanowire layer to prevent corrosion and/or ESD events in the silver nanowire layer during the fabrication of the stackup. In some examples, the passivation layer (and including the antistatic and/or anticorrosion layers) can have photosensitivity characteristics to allow for photo-patterning of the silver nanowire touch electrodes. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A-1B  illustrate touch sensor panels including touch electrodes according to examples of the disclosure. 
         FIGS. 2A-2D  illustrate an exemplary AgNW touch sensor panel structure that includes top and bottom overcoat layers that are adjacent to the AgNW layer from both sides for protecting the AgNW layer from corrosion according to examples of the disclosure. 
         FIGS. 3A-3D  illustrate an exemplary process for forming touch electrodes using the AgNW stackup of  FIGS. 2A-2D  according to examples of the disclosure. 
         FIG. 4  illustrates silver nanowires in the AgNW layer surrounded by an outer shell of electrochemically stable material to protect the silver nanowires from ionization according to examples of the disclosure. 
         FIGS. 5A-5D  illustrate touch sensor panel stack-ups including one or more silver nanowire layers and an anti-static layer according to examples of the disclosure. 
         FIGS. 6A-6C  illustrate exemplary touch sensor panel stack-ups that include silver nanowire layers, anti-static layers, and passivation layers according to examples of the disclosure. 
         FIG. 7  illustrates an exemplary touch sensor panel stack-up including an antistatic layer  704  and an anticorrosion layer according to examples of the disclosure. 
         FIG. 8  illustrates a process for forming a touch sensor panel according to examples of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description of examples, reference is made to the accompanying drawings which form a part hereof, and in which it is shown by way of illustration specific examples that can be practiced. It is to be understood that other examples can be used and structural changes can be made without departing from the scope of the disclosed examples. 
     This disclosure relates touch sensor stackups including silver nanowire (or other suitable conductors). In some examples, one or more anticorrosion layers can be used to protect silver nanowire materials used to form touch electrodes on a touch sensor panel from ionization (to reduce migration of ionic compounds that may cause corrosion of the touch electrodes). In some examples, the touch sensor panel stackups include one or more overcoat layers (e.g., on one or both sides) of the silver nanowire layer. The one or more of the overcoat layers can include anticorrosion compounds that protect the silver nanowire layer from ionization. In some examples, the touch sensor panel stackup can include a passivation layer that includes anticorrosion compounds (e.g., embedded in the passivation layer or deposited as anticorrosion layer on the passivation layer) that protect the silver nanowire layer from ionization (e.g., including protecting the sidewalls of the silver nanowire layer that may be exposed during photo-lithography). In some examples, the silver nanowire layer includes silver nanowires that include electrochemically stable (e.g., electrocatalytic activity less than a threshold) outer shells that protect the silver nanowires from ionization (e.g., in the ionic solutions that may be present during manufacture). 
     Additionally or alternatively, the touch sensor stackup can including one or more anti-static layers to protect against electrostatic discharge (ESD) during manufacturing or during layer use. For example, silver nanowires can be susceptible to ESD due to its nanostructure, which may nanowires with diameters less than 50 nm that may be damaged due to concentrated Joule heating during an ESD event. The one or more anti-static layers can dissipate ESD charge before the ESD charge builds up at the silver nanowire layer. 
     Additionally or alternatively, one or more anticorrosion layers and/or one or more antistatic layers can be formed with a passivation layer therebetween in one or more processes. The passivation layer, one or more anticorrosion layers and/or one or more antistatic layers can then be laminated to the silver nanowire layer to prevent corrosion and/or ESD events in the silver nanowire layer during the fabrication of the stackup. In some examples, the passivation layer (and including the antistatic and/or anticorrosion layers) can have photosensitivity characteristics to allow for photo-patterning of the silver nanowire touch electrodes. 
       FIGS. 1A-1B  illustrate touch sensor panels including touch electrodes according to examples of the disclosure.  FIG. 1A  illustrates touch sensor panel  100  with a plurality of row electrodes  104  and a plurality of column electrodes  106 . In some examples, touch sensor panel  100  can include one or more touch electrodes disposed as columns that form column electrodes  106  (e.g., single contiguous electrodes, or noncontiguous electrodes electrically coupled together using electrical bridges), and one or more touch electrodes disposed as rows that form row electrodes  104  (e.g., single contiguous electrodes, or noncontiguous electrodes electrically coupled together using electrical bridges). In some examples, column electrodes  106  can be sense lines, and row electrodes  104  can be drive lines, though in some examples, column electrodes  106  can be drive lines and row electrodes  104  can be sense lines. The electrodes  104  and  106  can be on the same or different material layers on touch sensor panel  100 , and the column electrodes  106  and the row electrodes  104  can intersect with each other while remaining electrically isolated from each other, as illustrated in  FIG. 1A . In some examples, touch sensor panel  100  can sense the self-capacitance of electrodes  104  and  106  to detect touch and/or proximity activity on touch sensor panel  100 , and in some examples, touch sensor panel  100  can sense the mutual capacitance between electrodes  104  and  106  to detect touch and/or proximity activity on touch sensor panel  100 . 
     Touch sensor panel  100  can also include bond pads that can facilitate electrical connections between row electrodes  104  and/or column electrodes  106  and other circuitry (e.g., touch sensing circuitry, driving circuitry, etc.). For example, touch sensor panel  100  can include bond pads  108  in the border region of touch sensor panel  100  that can be electrically connected to column electrodes  106  via routing traces. Touch sensor panel  100  can similarly include other bond pads in the border region of touch sensor panel  100  for electrically connecting to other column electrodes  106  and row electrodes  104  on touch sensor panel. It is understood that in some examples, bond pads  108  can be outside of the border region, such as on a tail that is bent behind the touch sensor panel to other circuitry (e.g., to a touch controller including driving and/or sensing circuitry). 
     Although  FIG. 1A  illustrates a touch sensor panel  100  in a row-column configuration, in some examples, a touch sensor panel can have a pixelated configuration.  FIG. 1B  illustrates touch sensor panel  102  with touch electrodes  110  arranged in a pixelated touch electrode configuration according to examples of the disclosure. Specifically, touch sensor panel  102  can include a plurality of individual touch electrodes  110 , each touch electrode identifying or representing a unique location on the touch sensor panel at which touch or proximity (i.e., a touch or proximity event) is to be sensed, and each touch electrode being electrically isolated from the other touch electrodes in the touch sensor panel. Touch electrodes  110  can be on the same or different material layers on touch screen  102 . In some examples, touch electrodes  110  can be substantially square-shaped (or rectangular-shaped) and distributed across touch sensor panel  100  in a matrix. For example, each rows of touch electrodes can include a plurality of touch electrodes, and each columns of touch electrodes can include a plurality of touch electrodes. 
     In some examples, touch sensor panels  100  or  102  can be based on self-capacitance. A self-capacitance based touch system can include a matrix of small, individual plates of conductive material or an array of conductive lines that can be referred to as touch electrodes (e.g., row electrodes  104  and column  106  electrodes as shown in  FIG. 1A , or touch electrodes  110  as shown in  FIG. 1B ). In some examples, each touch electrode can be individually coupled to sense circuitry via individual traces—thus, each touch electrode can be individually addressable by the touch sensing system. During operation, a touch electrode can be stimulated with an alternating current (AC) waveform, and the self-capacitance to ground of the touch electrode can be measured. As an object approaches the touch electrode, the self-capacitance to ground of the touch electrode can change (e.g., increase). This change in the self-capacitance of the touch electrode can be detected and measured by the touch sensing system to determine the positions of multiple objects when they touch, or come in proximity to, the touch sensor panel. In some examples, the electrodes of a self-capacitance based touch system can be formed from rows and columns of conductive material (e.g., as shown in  FIG. 1A ), and changes in the self-capacitance to ground of the row electrodes and column electrodes can be detected. In some examples, the electrodes of a self-capacitance based touch system can be formed of pixelated touch electrodes (e.g., as shown in  FIG. 1B ), and changes in the self-capacitance to ground of the touch electrodes can be detected. In some examples, a touch sensor panel can be multi-touch, single touch, projection scan, full-imaging multi-touch, capacitive touch, etc. 
     In some examples, touch sensor panels  100  and  102  can be based on mutual capacitance. A mutual capacitance based touch system can include drive and sense lines (e.g., row electrodes  104  and column electrodes  106 , respectively) that may cross over each other on different layers, or may be adjacent to each other on the same layer. The crossing or adjacent locations can be referred to as touch nodes. During operation, the drive line can be stimulated with an AC waveform and the mutual capacitance of the touch node can be measured. As an object approaches the touch node, the mutual capacitance of the touch node can change (e.g., decrease). This change in the mutual capacitance of the touch node can be detected and measured by the touch sensing system to determine the positions of multiple objects when they touch, or come in proximity to, the touch screen. In a similar manner a mutual capacitance based touch system can include touch electrodes (e.g., touch electrodes  110 ) that may be adjacent to each other on the same layer (e.g., as illustrated in  FIG. 1B ). The adjacent locations between a touch electrode in a drive configuration (e.g., coupled to drive circuitry) and a touch electrode in a sense configuration (e.g., coupled to sense circuitry) can be referred to as touch nodes. During operation, the touch electrode in a drive configuration can be stimulated with an AC waveform and the mutual capacitance of the touch node can be measured by a touch electrode in a sense configuration. As an object approaches the touch node, the mutual capacitance of the touch node can change (e.g., decrease). This change in the mutual capacitance of the touch node can be detected and measured by the touch sensing system to determine the positions of multiple objects when they touch, or come in proximity to, the touch screen. 
     In some examples, touch sensor panels  100  or  102  can be implemented with an opaque touch-sensing surface. In some examples, touch sensor panels  100  or  102  can overlay or be an integrated with a display to form a touch screen. In some integrated touch screens, touch sensing circuit elements of the touch sensing system can be integrated into the display pixel stackups of a display. The circuit elements in the touch screen can include, for example, elements that can exist in LCD or other displays (e.g., light emitting diode (LED) display or organic light emitting diode (OLED), etc.), such as one or more pixel transistors (e.g., thin film transistors (TFTs)), gate lines, data lines, pixel electrodes and common electrodes. In a given display pixel, a voltage between a pixel electrode and a common electrode can control a luminance of the display pixel. The voltage on the pixel electrode can be supplied by a data line through a pixel transistor, which can be controlled by a gate line. It is noted that circuit elements are not limited to whole circuit components, such as a whole capacitor, a whole transistor, etc., but can include portions of circuitry, such as only one of the two plates of a parallel plate capacitor. 
     In some examples, it can be desirable to use silver nanowires (AgNW) (or more generally silver nano materials) to form the touch electrodes of the touch sensor panel due to various electrical, mechanical, structural, optical, etc. characteristics of AgNW that can be beneficial for a particular application of a touch sensor panel. However, AgNW nanowire or other nanomaterials can be susceptible to Ag corrosion, ionization and/or migration, which can result in structural, optical, mechanical and/or electrical degradation of the touch electrodes over time. Some examples of the disclosure provide for various manners of protecting AgNW or other silver nanomaterials used in touch sensor panels from the above corrosion (e.g., providing Ag migration/corrosion resistance). Additionally or alternatively, AgNW or other nanomaterials may be susceptible to electrostatic discharge (ESD) compared with other touch electrode materials (e.g., ITO) due to the electric currents being densely confined in the nanowire diameter and that flow across nanowire junctions (as compared with the electric currents being uniformly spread out in a uniform ITO material layer). Such ESD events can damage the silver nanowire due to concentrated Joule heading from the densely confined electric currents. Some examples of the disclosure provide for various manners of protecting AgNW or other silver nanomaterials used in touch sensor panels from the above ESD event (e.g., providing ESD resistance). 
       FIGS. 2A-2D  illustrate an exemplary AgNW touch sensor panel structure that includes top and bottom overcoat layers that are adjacent to the AgNW layer from both sides for protecting the AgNW layer from corrosion according to examples of the disclosure. The structure can include a polyethylene terephthalate (PET) substrate  200  (or any other suitable substrate on which to form the AgNW touch electrodes), a bottom overcoat layer  202  on top of substrate  200 , a AgNW layer  204  on top of the bottom overcoat layer  202 , a top overcoat layer  206  on top of the AgNW layer  204 , a cushion layer  208  on top of the top overcoat layer  206 , and a top PET substrate  210  (or any other suitable substrate). In some examples, the above layers can be formed one on top of the other as shown in  FIGS. 2A-2D . 
     Bottom overcoat layer  202  can serve one or more functions. For example, bottom overcoat layer  202  can be configured to facilitate robust adhesion of AgNW layer  204  to the stackup. Bottom overcoat layer  202  can also be photo-sensitive such that it can be patterned during photolithography (e.g., as described with reference to  FIGS. 3A-3D ). Thus, in some examples, bottom overcoat layer  202  can include photoinitiators (e.g., i-line ultraviolet (UV) photoinitiators and/or g-line UV photoinitiators). In some examples, bottom overcoat layer  202  can include i-line UV photoinitiators for top side lithography (e.g., lithography with light from above the stackup), and/or g-line UV for bottom side lithography (e.g., lithography with light from below the stackup). Further, in some examples, bottom overcoat layer  202  can be configured to perform an anticorrosion function for AgNW layer  204 . Specifically, bottom overcoat layer  202  can be a polymer layer that chemically passivates the AgNW layer  204  surface to prevent Ag ionization. In some examples, bottom overcoat layer  202  can be hydrophobic or chemically inert to H 2 O, OH − , H + , and/or other ionic compounds. In some examples, bottom overcoat layer  202  can include one or more anticorrosion compounds that help prevent Ag ionization of the bottom surface of AgNW layer  204  (though in some examples, bottom overcoat layer  202  does not include such compounds). 
     AgNW layer  204  can be a layer of silver nanowires, such as for use as touch electrodes. Like bottom overcoat layer  202 , top overcoat layer  206  can also serve one or more functions. For example, top overcoat layer  206  can be configured to protect AgNW layer  204  from chemical processes that might occur during fabrication of the touch sensor panel (e.g., during photolithography, developing, etc.). Top overcoat layer  206  can also be photo-sensitive such that it can be patterned during photolithography (e.g., as described with reference to  FIGS. 3A-3D ). Thus, in some examples, top overcoat layer  206  can include photoinitiators (e.g., i-line UV photoinitiators and/or g-line UV photoinitiators). In some examples, top overcoat layer  206  can include i-line UV photoinitiators for top side lithography (e.g., lithography with light from above the stackup), and/or g-line UV for bottom side lithography (e.g., lithography with light from below the stackup). Further, in some examples, top overcoat layer  206  can be configured to perform an anticorrosion function for AgNW layer  204 . Specifically, top overcoat layer  206  can be a polymer layer that chemically passivates the AgNW layer  204  surface to prevent Ag ionization. In some examples, top overcoat layer  206  can be hydrophobic or chemically inert to H 2 O, OH − , H + , and/or other ionic compounds. In some examples, top overcoat layer  206  can include one or more anticorrosion compounds that help prevent Ag ionization of the bottom surface of AgNW layer  204  (though in some examples, top overcoat layer  206  does not include such compounds). In some examples, both bottom overcoat layer  202  and top overcoat layer  206  can include anticorrosion compounds, or only one of bottom overcoat layer  202  and top overcoat layer  206  can include such anticorrosion compounds, or neither of bottom overcoat layer  202  and top overcoat layer  206  can include such anticorrosion compounds. In some examples, the thicknesses of bottom overcoat layer  202  and top overcoat layer  206  can be less than 200 nm, less than 150 nm, or less than 100 nm. 
     Cushion layer  208  and top PET substrate  210  can be included in the stackup to provide for structural stability to the stackup during fabrication and/or to allow for process steps to occur in the fabrication of the touch sensor panel (e.g., acting as a carrier film for roll-to-roll lamination). In some examples, cushion layer  208  can be made of the same base material as bottom overcoat layer  202  and top overcoat layer  206 , except that it can lack anticorrosion compounds (e.g., because cushion layer  208  is not in contact with AgNW layer  204 , and thus need not include such compounds) and it can lack photoinitiators (e.g., because cushion layer  208  need not be patternable during lithography, and can be fully removed from the stackup during the lithography step). 
       FIGS. 3A-3D  illustrate an exemplary process for forming touch electrodes using the AgNW stackup of  FIGS. 2A-2D  according to examples of the disclosure. In  FIG. 3A , a stackup of bottom overcoat layer  302 , AgNW layer  304 , top overcoat layer  306 , cushion layer  308  and top substrate  310  can be rolled onto substrate  300 . In  FIG. 3B , a masking layer  312  can be formed on top of top substrate  310  to define the patterns of the touch electrodes, and light  314  (e.g., i-line UV) can be directed towards the stackup from above. Light  314  can photoactivate top overcoat layer  306  and bottom overcoat layer  302 , while the other layers do not react to light  314 . Subsequently, top substrate and mask  312  can be removed, and the remaining layers can be developed/removed/etched to result in patterns of top overcoat layer  306 , AgNW layer  304  and bottom overcoat layer  302  formed on top of substrate  300 , as shown in  FIG. 3C . These patterns can form touch electrodes for the touch sensor panel. 
     In some examples, the sidewalls of AgNW layer  304  in  FIG. 3C  can be exposed to possible ionization, because the anticorrosion compounds of top and bottom overcoat layers  306  and  302  may only be in contact with the top and bottom surfaces of AgNW layer  304 , and not in contact with the sidewalls of the patterned AgNW layer  304 . Thus, in some examples, a passivation layer that is formed on top of the structure of  FIG. 3C  can include anticorrosion compounds (like in top and bottom overcoat layers  306  and  302 ) to protect the sidewalls of the AgNW layer  304  from ionization, such as shown in  FIG. 3D . 
     For example, in  FIG. 3D , a film  316  of anticorrosion materials is formed over the patterned AgNW structures, and a passivation layer  318  is formed on top of that. The anticorrosion compounds in film  316  can be the same or different than the compounds included in top  306  and/or bottom  302  overcoat layers. As shown in  FIG. 3D , film  316  can be in contact with the sidewalls of AgNW layer  304 , thus protecting those sidewalls from ionization. In some examples, film  316  may not be a permanent physical layer (e.g., it may be absorbed by the AgNW layer and/or other layers, such as in the case of a wet spray anticorrosion film that can be sprayed over the AgNW structures before the deposition of the passivation layer  318 ), and thus may not present as a physical layer, but may be detectable with chemical analysis. In some examples, instead of being a separate layer, the anticorrosion compounds can be incorporated into passivation layer  318  (e.g., similar to top and bottom overcoat layer  306  and  302 ), thus eliminating the need to perform two separate steps for passivating the stackup of  FIG. 3C . In some examples, no anticorrosion compounds/films are used in passivating the stackup of  FIG. 3C  (e.g., a passivation layer  318  is formed over the patterned AgNW structures without anticorrosion compounds in the passivation layer and without depositing an anticorrosion layer over the AgNW structures) such that the anticorrosion functions of the stackup are, instead, performed by the top and bottom overcoat layers  306  and  302 . 
     In some examples, the above process of  FIGS. 3A-3D  can be repeated or performed in parallel with the same stackup (e.g., layers  302 ,  304 ,  306 ,  308 ,  310 ) positioned underneath substrate  300  to result in a structure of touch electrodes on both sides of substrate  300  (e.g., top and bottom of substrate  300 ). 
     Alternatively or in addition to any of the examples disclosed above, the AgNW layer can have characteristics for reducing ionization of the AgNW layer. For example, the AgNW layer can include anticorrosion compounds (e.g., anticorrosion compounds used in the top and bottom overcoat layers and/or the passivation layer). Additionally or alternatively, the silver nanowires in the AgNW layer can be surrounded by an outer shell of electrochemically stable material to protect the silver nanowires from ionization, such as shown in  FIG. 4 . For example, in  FIG. 4 , silver nanowires  404 , which can be disposed in a binding material  408  for binding the silver nanowires together in the AgNW layer, can have outer shell layers  406  that are electrochemically stable (e.g., to H 2 O, OH − , H + , and/or other ionic compounds), such as Pt, Pd, Ni, etc. In some examples, shell layers  406  can be formed on silver nanowires  404  by electrodeposition and/or by chemical catalysts. In this way, the AgNW layer of the touch sensor panel can be (further) protected from Ag ionization. 
     As described herein, in some examples, the risk of an ESD event damaging the silver nanowire layer can be mitigated by applying an anti-static layer or coating over the silver nanowire layer. In some examples, the antistatic layer can be disposed directly on the silver nanowire layer, or indirectly (e.g., with other intervening layers). The anti-static layer can be a resistive layer with high sheet resistance and can be implemented by coating, spraying, or printing resistive materials (e.g., polystyrene sulfonate (PEDOT)). The anti-static layer can, in some examples, also be transparent or substantially transparent to reduce optical impact to the stackup (e.g., for a touch screen implementation). 
       FIGS. 5A-5D  illustrate touch sensor panel stack-ups including one or more silver nanowire layers and an anti-static layer according to examples of the disclosure. In some examples, an anti-static layer can be transparent or translucent (e.g., for touch screen applications). In some examples, an anti-static layer can be opaque (e.g., for non-display touch-sensitive surfaces). In some examples, the anti-static layer can be formed between the top substrate (cover glass or other transparent, translucent or opaque substrate) and an adhesive layer (as shown in  FIG. 5A ), on top of the top substrate (as shown in  FIG. 5B ), or between the adhesive and silver nanowire layer (as shown in  FIG. 5C ). In some examples, the anti-static material can be integrated with an adhesive (e.g., such as an optically clear adhesive (OCA) as shown in  FIG. 5D ) or with another layer (e.g., a substrate or passivation layer). 
       FIG. 5A  illustrates an exemplary touch sensor panel stack-up  500  including one or more silver nanowire layers  508   a  and  508   b  and an anti-static layer  504  according to examples of the disclosure. In some examples, the touch sensor panel stack-up  500  includes a cover glass  502 , an anti-static layer  504 , a first adhesive layer  506   a , a first silver nanowire layer  508   a , a substrate  510 , a second silver nanowire layer  508   b , a second adhesive layer  506   b , and a display  512 . 
     In some examples, the substrate  510  can be a flexible or rigid material that provides support to one or more other layers in the stack-up  500  at one or more points in time during the manufacturing process and/or once the touch sensor panel is complete. In situations where the touch sensor panel is part of a touch screen (e.g., integrated with or overlaid on a display  512 ), the substrate  510  can include a transparent or substantially transparent material. In situations where the touch sensor panel is not part of a touch screen (e.g., the touch sensor panel is implemented with an opaque touch-sensitive surface, such as a trackpad), the substrate  510  can include an opaque material. In some examples, the substrate  510  is non-conductive and can electrically isolate one or more silver nanowire layers  508   a  and  508   b  from each other and/or from other electrical components in the stack-up. Although  FIG. 5A  illustrates substrate  510  as a single layer, in some examples, the substrate  510  is formed from multiple substrate layers joined together by an adhesive. 
     In some examples, the first silver nanowire layer  508   a  can be located on a first side (e.g., the top side) of substrate  510 . In some examples (e.g., in a double-sided touch sensor panel implementation), the touch sensor panel stackup  500  can also include a second silver nanowire layer  508   b  on the second side (e.g., the bottom side) of the substrate  510 , though in other examples, the second silver nanowire layer  508   b  is omitted (e.g., in a single-sided touch sensor panel implementation). The silver nanowire layers  508   a  and  508   b  can be the same as other silver nanowire layers described herein. For example, the silver nanowire layers  508   a  and  508   b  can include a plurality of touch electrodes formed from silver nanomaterials that can be used to sense objects proximate to and/or touching the touch sensor panel. 
     The touch sensor panel stackup  500  can further include a cover glass  502 . In some examples, the cover glass  502  can be formed from a material other than glass. In some examples where the touch sensor panel is incorporated into or overlaid with a display  512  (e.g., the touch sensor panel is part of a touch screen), the cover glass  502  can include a transparent material such as glass, plastic, or any other suitable material that protects the rest of the stack up from damage. In some examples where the touch sensor panel is not incorporated into or overlaid on a display  512  (e.g., the touch sensor panel is implemented as part of a trackpad or other opaque touch-sensitive surface), the cover glass  502  can include opaque materials such as glass, plastic, metal, and the like. 
     As described above, in some examples, the touch sensor panel stackup  500  can be included in a touch screen that has a display  512 . In some examples, one or more touch sensing components can be integrated with one or more display components (e.g., dual-purpose components such as electrodes, gate lines, etc.) or one or more touch sensing components can be overlaid on the one or more display components (e.g., overlaying a transparent touch sensor panel over a display). Display  512  can include display pixels configured to display one or more images on an electronic device, for example. In some examples, the touch sensor panel is not integrated with or overlaid on a display. For example, the touch sensor panel can be included in a trackpad or other non-display touch sensing input device. Thus, in some examples, display  512  is omitted from touch sensor panel stack-up  500 . 
     In some examples, the touch sensor panel stack-up  500  can include two or more layers joined together by adhesive layers  506   a  and  506   b . In some examples, such as in touch screen examples including a display  512 , the adhesive layers  506   a  and  506   b  can include an optically clear adhesive material that does not or substantially does not interfere with visibility of display  512 . In some examples, such as in non-touch screen examples that do not include a display  512 , the adhesive layers  506   a  and  506   b  can include opaque adhesives in addition or as an alternative to optically clear adhesive materials. In some examples, the second silver nanowire layer  508   b  and display  512  can be joined by adhesive layer  506   b . In some examples, the second adhesive layer  506   b  can optionally include an air gap in some examples, or can be omitted for an air gap over display  512 . For example, the silver nanowire layer  508   b  and the display  512  may not completely make contact and an air gap can be included therebetween. In some examples, the first silver nanowire layer  508   a  and the antistatic layer  504  can be joined together by adhesive layer  506   a . Thus, in some examples, the anti-static layer  504  can be located between an adhesive layer  506   a  and the cover glass  502 . 
       FIG. 5B  illustrates an exemplary touch sensor panel stack-up  514  including one or more silver nanowire layers  508   a  and  508   b  and an anti-static layer  504  according to examples of the disclosure. In some examples, the touch sensor panel stack-up  500  includes a cover glass  502 , an anti-static layer  504 , a first adhesive layer  506   a , a first silver nanowire layer  508   a , a substrate  510 , a second silver nanowire layer  508   b , a second adhesive layer  506   b , and a display  512 . The components of stack-up  514  can be the same as or similar to the components of stack-up  500  described above with reference to  FIG. 5A , but the arrangement of some of the components can be different in some examples. For example, the anti-static layer  504  can be located on top of the cover glass  502  in stack-up  500  (e.g., the cover glass  502  can be between the anti-static layer  504  and one or more other layers of the stackup, such as the adhesive layer  506   a ). 
       FIG. 5C  illustrates an exemplary touch sensor panel stack-up  516  including one or more silver nanowire layers  508   a  and  508   b  and an anti-static layer  504  according to examples of the disclosure. In some examples, the touch sensor panel stack-up  500  includes a cover glass  502 , an anti-static layer  504 , a first adhesive layer  506   a , a first silver nanowire layer  508   a , a substrate  510 , a second silver nanowire layer  508   b , a second adhesive layer  506   b , and a display  512 . The components of stack-up  516  can be the same as or similar to the components of stack-ups  500  and  514  described above with reference to  FIGS. 5A-5B , but the arrangement of some of the components can be different in some examples. For example, the anti-static layer  504  can be located between the adhesive layer  506   a  and the first silver nanowire layer  508   a  in stack-up  516 . 
       FIG. 5D  illustrates an exemplary touch sensor panel stack-up  516  including one or more silver nanowire layers  508   a  and  508   b  and an anti-static adhesive layer  520  according to examples of the disclosure. In some examples, the touch sensor panel stack-up  500  includes a cover glass  502 , an anti-static adhesive layer  520 , a first silver nanowire layer  508   a , a substrate  510 , a second silver nanowire layer  508   b , a second adhesive layer  506   b , and a display  512 . The components of stack-up  518  can be the same as or similar to the components of stack-ups  500 ,  514 , and  516  described above with reference to  FIGS. 5A-5C , except stack up  518  can include an anti-static adhesive layer  520  (e.g., an adhesive layer including anti-static compounds) between the first silver nanowire layer  508   a  and the cover glass  502  instead of including an anti-static layer  504  that is separate from the first adhesive layer  506   a.    
       FIGS. 6A-6C  illustrate exemplary touch sensor panel stack-ups that include silver nanowire layers, anti-static layers, and passivation layers according to some examples of the disclosure. In some examples, passivation layers can provide structural support for one or more stack-up layers and/or protection from moisture damage to the silver nanowire layers in the stackup. As will be described in more detail below, the passivation layers can be dedicated layers in the stack-up (e.g., as shown in  FIGS. 6A and 6C ) or incorporated with an anti-static layer (e.g., as shown in  FIG. 6B ), for example. 
       FIG. 6A  illustrates an exemplary touch sensor panel stack-up  600  that includes silver nanowire layers  508   a  and  508   b , an anti-static layer  504 , and passivation layers  602   a  and  602   b  according to some examples of the disclosure. The stack-up  600  can include cover glass  502 , adhesive layers  506   a  and  506   b , anti-static layer  504 , silver nanowire layers  508   a  and  508   b , substrate  510 , and display  512  described above with reference to  FIGS. 5A-5D , for example. In some examples, stack-up  600  can further include a first passivation layer  602   a  located on a first (e.g., top) side of the first silver nanowire layer  508   a . For example, the first passivation layer  602   a  can be located between the first silver nanowire layer  508   a  and the anti-static layer  504 . In some examples, stack-up  600  can further include a second passivation layer  602   b  on a second (e.g., bottom) side of the second silver nanowire layer  508   b . For example, the second passivation layer  602   b  can be located between the second silver nanowire layer  508   b  and the second adhesive layer  506   b.    
       FIG. 6B  illustrates an exemplary touch sensor panel stack-up  604  that includes silver nanowire layers  508   a  and  508   b , an anti-static passivation layer  606 , and passivation layer  602   b  according to some examples of the disclosure. The stack-up  600  can include cover glass  502 , adhesive layers  506   a  and  506   b , silver nanowire layers  508   a  and  508   b , substrate  510 , and display  512  described above with reference to  FIGS. 5A-6A  and second passivation layer  602   b  described with reference to  FIG. 6A , for example. In some examples, stack-up  600  can further include an anti-static passivation layer  606  that provides the structural support and/or protection from moisture of a passivation layer (e.g., passivation layer  602   a  or  602   b ) and has anti-static properties similar to anti-static layer  504 . The anti-static passivation layer  606  can be located between the first adhesive layer  506   a  and the first silver nanowire layer  508   a.    
       FIG. 6C  illustrates an exemplary touch sensor panel stack-up  604  that includes silver nanowire layers  508   a  and  508   b , an anti-static cover glass  610 , and passivation layers  602   a  and  602   bb  according to some examples of the disclosure. The stack-up  600  can include adhesive layers  506   a  and  506   b , silver nanowire layers  508   a  and  508   b , substrate  510 , and display  512  described above with reference to  FIGS. 5A-6B , first passivation layer  602   a  described with reference to  FIG. 6A , and second passivation layer  602   b  described with reference to  FIGS. 6A-6B , for example. In some examples, stack-up  600  can further include an anti-static cover glass  610 . The cover glass  610  can include one or more of the materials of cover glass  502  described above and anti-static materials. 
     In some examples, a touch sensor panel stack up can include both the anticorrosion and the antistatic features described herein. For example,  FIG. 7  illustrates a touch sensor panel stack-up  700  including an antistatic layer  704  and an anticorrosion layer  708  according to examples of the disclosure. Touch sensor panel stack-up  700  includes a silver nanowire touch sensor panel  716  including a silver nanowire layer  712  formed on substrate  714  (e.g., PET or other suitable material). Touch sensor panel stack-up  700  also including a multi-layered protective film  710  including an antistatic layer  704 , a passivation layer  706  and an anticorrosion layer  708 . As described herein, the layers of protective film  710  can be formed on a carrier  702 . 
     Antistatic layer  704  can correspond to an antistatic material (e.g., PEDOT or other suitable material with high sheet resistance), and can provide protection against ESD events during manufacture or later use by an end user. Passivation layer  706  can correspond to a passivating material that can provide physical protection and moisture resistance for the silver nanowire touch electrodes (e.g., in a similar manner to passivation layer  318 ). Anticorrosion layer  708  can include one or more anticorrosion compounds that can prevent or otherwise reduce Ag ionization (e.g., as described with respect to bottom overcoat layer  302 , top overcoat layer  306  or film  316 ). 
     In some examples, anticorrosion layer  708  may be incorporated proximate to the AgNW touch electrodes (e.g., as described with respect to  FIG. 3A ), passivation layer  706  (e.g., an organic passivation layer) including antistatic materials can be disposed on top of AgNW touch electrodes (and over anticorrosion layer  708 ) for physical protection, moisture resistance and antistatic protection (e.g., the passivation layer can include photoinitiators that can be photo-patterned. In some examples, fabricating antistatic layer  704 , passivation layer  706  and anticorrosion layer  708  in this manner (including antistatic materials in the passivation layer, as illustrated in  FIG. 6B , for example)) can result in short the silver nanowire touch electrodes due to migration of the antistatic material (e.g., metal nanoparticles or other suitable materials) in the wet passivation material (which may be wet coated or sprayed) or can result in decreased photosensitivity of the passivation layer due to embedded antistatic materials, which may impact the reliability of photo-patterning onto silver nanowire touch sensor panel  716 . 
     In some examples, antistatic layer  704 , passivation layer  706  (e.g., a photosensitive organic passivation layer) and anticorrosion layer  708  can be formed on a carrier  702  in multiple steps to form a dry multi-layered protective film  710 . In some examples, the antistatic material can be wet coated, sprayed or printed on a carrier  702  (e.g., a flexible substrate, such as PET or other suitable substrate materials) and subsequently dried. Then, passivation layer  706  can be wet coat, sprayed or printed on antistatic layer  704 , and subsequently dried. Then, anticorrosion layer  708  can be wet coat, sprayed or printed on passivation layer  706 , and subsequently dried. This photosensitive, dry multi-layered protective film can then be laminated (with or without an intermediate adhesive) onto silver nanowire touch sensor panel  716  (e.g., in a roll-to-roll process or other suitable process). In some examples, the lamination can be an elevated temperature roller lamination (e.g., at a temperature between 75-100° C.). In some examples, the lamination can be performed under vacuum conditions and/or subjected to an autoclave processing step (applying elevated temperature and pressure) to reduce the potential for the formation of lamination bubbles. The dry multi-layered protective film  710  can then be exposed to light (e.g., in the ultraviolent or other suitable wavelength range) to pattern the touch sensor panel as defined by a photomask (e.g., in a similar manner as discussed above with respect to  FIG. 3B ), and subsequently followed by solvent development, drying and/or thermal annealing. 
     In some examples, carrier  702  can be removed (e.g., after laminating the protective layers of the multi-layered protective film  710  to silver nanowire touch sensor panel  716 , or later in the manufacturing process. In some examples, touch sensor panel stack-up  700  (with or without carrier  702  can be integrated with additional layers such as a display (e.g., laminated with an OCA to bottom side of substrate  714 ) and/or with a top surface (e.g., a cover glass or opaque surface laminated with an OCA or other adhesive to carrier  702  or to anti-static layer  704 ). 
     It should be understood that touch sensor panel stackup  700  is one example, stackup but that different stackups are possible, including more, fewer or different layers in the same or different order. For example, silver nanowire touch sensor panel  716  can be formed as described in  FIGS. 3A-3D  and multi-layered protective film  710  can be disposed on the passivation layer  318 . Additionally, although stack-up  700  shows a single silver nanowire layer (e.g., corresponding to a single-sided touch sensor panel), that stackup  700  can be modified to include a second silver nanowire layer on the opposite side of substrate  714  (e.g., in a similar manner as illustrated in  FIGS. 5A-6C ). 
       FIG. 8  illustrates a process  800  for forming a touch sensor panel (e.g., corresponding to touch sensor panel stack up  700 ) according to examples of the disclosure. At  805 , silver nanowire layer can be formed on a substrate (e.g., corresponding to silver nanowire touch sensor panel  716 ). At  810 , a multi-layer protective film can be formed (e.g., corresponding to multi-layered protective film  710 ). The multi-layer protective film comprising an antistatic layer (e.g., corresponding to antistatic layer  704 ), a passivation layer (e.g., corresponding to passivation layer  706 ), and an anticorrosion layer (e.g., corresponding to anticorrosion layer  708 ). In some examples, the multi-layer protective film can be formed using a sequence of wet coating (or spraying or printing) and drying. For example, the antistatic layer can be formed by wet coating and drying an antistatic material on a substrate (e.g., corresponding to carrier  702 ), the passivation layer can be formed by wet coating and drying passivation material on the antistatic layer, and the anticorrosion layer can be formed by wet coating and drying anticorrosion material on the passivation layer ( 815 ). At  820 , the touch sensor panel can be formed by laminating the silver nanowire layer to the dry multi-layer protective film. Using an antistatic, anticorrosive and photo-patternable dry film can reduce the occurrence of ionization/corrosion and/or ESD events as described herein. 
     Therefore, according to the above, examples of the disclosure are directed to touch sensor panel stackups including one or more silver nanowire layers and various manners of protecting AgNW layers of a touch sensor panel from ionization and/or ESD event. 
     Therefore, according to the above, some examples of the disclosure are directed to a touch sensor panel comprising: a substrate; a silver nanowire layer on the substrate that forms one or more touch electrodes on the touch sensor panel, wherein the silver nanowire layer includes a first side and a second side, opposite the first side; a first overcoat layer disposed on and in contact with the first side of the silver nanowire layer; and a second overcoat layer disposed on and in contact with the second side of the silver nanowire layer, wherein at least one of the first overcoat layer and the second overcoat layer includes one or more anticorrosion compounds configured to protect the silver nanowire layer from ionization. Additionally or alternatively to one or more of the examples above, in some examples, the touch sensor panel further comprises: a passivation layer formed on the first overcoat layer, the second overcoat layer and the silver nanowire layer, the passivation layer including one or more anticorrosion compounds configured to protect one or more sidewalls of the silver nanowire layer from ionization. Additionally or alternatively to one or more of the examples above, in some examples, the silver nanowire layer includes silver nanowires that have electrochemically stable outer shells. Additionally or alternatively to one or more of the examples above, in some examples, the touch sensor panel further comprises: an anticorrosion layer deposited on the first overcoat layer, the second overcoat layer and the silver nanowire layer, the anticorrosion layer including one or more anticorrosion compounds configured to protect one or more sidewalls of the silver nanowire layer from ionization; and a passivation layer formed over the anticorrosion layer. Additionally or alternatively to one or more of the examples above, in some examples, the touch sensor panel further comprises: a passivation layer formed on the first overcoat layer, the second overcoat layer and the silver nanowire layer, without an intervening anticorrosion layer. Additionally or alternatively to one or more of the examples above, in some examples, the touch sensor panel further comprises: a passivation layer formed on the first overcoat layer, the second overcoat layer and the silver nanowire layer, wherein at least a portion of the silver nanowire layer includes anticorrosion compounds that were absorbed by the silver nanowire layer from an anticorrosion film that was deposited on the first overcoat layer, the second overcoat layer and the silver nanowire layer before the passivation layer was formed on the first overcoat layer, the second overcoat layer and the silver nanowire layer. 
     Some examples of the disclosure are directed to a touch sensor panel. The touch sensor panel can comprise: a substrate; a silver nanowire layer disposed on the substrate; and a multi-layer protective film disposed on the silver nanowire layer. One or more touch electrodes of the touch sensor panel are formed from silver nanowires in the silver nanowire layer. The multi-layer protective film can comprise an antistatic layer, a passivation layer, and an anticorrosion layer. Additionally or alternatively to one or more of the examples above, in some examples, the passivation layer can be disposed between the antistatic layer and the anticorrosion layer. Additionally or alternatively to one or more of the examples above, in some examples, the passivation layer can be an organic passivation layer. Additionally or alternatively to one or more of the examples above, in some examples, the passivation layer can include photoinitiators. Additionally or alternatively to one or more of the examples above, in some examples, the multi-layer protective film can be photo-patternable. Additionally or alternatively to one or more of the examples above, in some examples, the multi-layer protective film can formed by wet coating and drying an antistatic material on a carrier to form the antistatic layer, by wet coating and drying passivation material on the antistatic layer to form the passivation layer, and by wet coating and drying anticorrosion material on the passivation layer to form the anticorrosion layer. Additionally or alternatively to one or more of the examples above, in some examples, the multi-layer protective film can be coupled to the silver nanowire layer such that the anticorrosion layer is closer to the silver nanowire layer than the passivation layer or the anticorrosion layer. Additionally or alternatively to one or more of the examples above, in some examples, the multi-layer protective film can be coupled to the silver nanowire layer such that the antistatic layer is further from the silver nanowire layer than the passivation layer or the antistatic layer. Additionally or alternatively to one or more of the examples above, in some examples, the silver nanowire layer can comprise silver nanowires with electrochemically stable outer shells. Additionally or alternatively to one or more of the examples above, in some examples, the touch sensor panel can further comprise one or more overcoat layers comprising anticorrosion compounds disposed on and in contact with the silver nanowire layer. 
     Some examples of the disclosure are directed to a method of forming a touch sensor panel. The method can comprise: forming a silver nanowire layer on a substrate; forming a multi-layer protective film, the multi-layer protective film comprising an antistatic layer, a passivation layer, and an anticorrosion layer; and laminating the multi-layer protective film and the silver nanowire layer. Additionally or alternatively to one or more of the examples above, in some examples, the method can further comprise forming one or more touch electrodes of the touch sensor panel from silver nanowires in the silver nanowire layer (e.g., via photolithography). Additionally or alternatively to one or more of the examples above, in some examples, forming the multi-layer protective film can comprise: wet coating and drying an antistatic material on a carrier to form the antistatic layer; wet coating and drying passivation material on the antistatic layer to form the passivation layer; and wet coating and drying anticorrosion material on the passivation layer to form the anticorrosion layer. Additionally or alternatively to one or more of the examples above, in some examples, laminating the multi-layer protective film and the silver nanowire layer can comprise lamination at an elevated temperature between 75-100° C. Additionally or alternatively to one or more of the examples above, in some examples, laminating the multi-layer protective film and the silver nanowire layer can comprise laminating the anticorrosion layer of the multi-layer protective film to the silver nanowire layer. Additionally or alternatively to one or more of the examples above, in some examples, the passivation layer can be disposed between the antistatic layer and the anticorrosion layer. Additionally or alternatively to one or more of the examples above, in some examples, the passivation layer can be an organic passivation layer. Additionally or alternatively to one or more of the examples above, in some examples, the multi-layer protective film can be photo-patternable, and the method can further comprise patterning the multi-layer protective film using a photolithography process (or other light exposure process). Additionally or alternatively to one or more of the examples above, in some examples, the antistatic layer can be further from the silver nanowire layer than the passivation layer or the antistatic layer. 
     Although examples of this disclosure have been fully described with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of examples of this disclosure as defined by the appended claims.

Metadata:
Filing Date: 20191112
Publication Date: 20210824
Grant Date: 20210824
Priority Date: 20181112
Inventors: CHAN, ISAAC WING-TAK
TUNG, CHUN-HAO
CHEN, SZ-HSIAO
DAI, Wenqing
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F3/047", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/044", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/047", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/044", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04104", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04107", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04104", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/044", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04107", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/047", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 77390202