PATENT DOCUMENT

Publication Number: US-8475872-B2
Application Number: US-62653609-A
Country: US
Kind Code: B2

Title: Patterning of thin film layers

Abstract:
Simplified patterning of layers of a thin film is disclosed. In some embodiments, the patterning can include patterning a first conductive layer using a patterned dielectric layer as a mask and patterning a second conductive layer using a patterned passivation layer as another mask. In other embodiments, the patterning can include patterning a first conductive layer using a removable photosensitive layer as a mask, patterning a black mask layer using a removable photo mask, and patterning a second conductive layer using a patterned passivation layer as another mask. In still other embodiments, the patterning can include patterning a first conductive layer using a patterned black mask layer as a mask and patterning a second conductive layer using a patterned passivation layer as another mask. An exemplary device utilizing the thin film so patterned can include a touch sensor panel.

Claims:
What is claimed is: 
     
       1. A method comprising:
 depositing a first conductive layer onto a surface; 
 patterning a dielectric layer on the first conductive layer; 
 patterning the first conductive layer using the patterned dielectric layer as a first mask; 
 depositing a second conductive layer onto the patterned dielectric layer; 
 patterning a passivation layer on the second conductive layer; and 
 patterning the second conductive layer using the patterned passivation layer as a second mask. 
 
     
     
       2. The method of  claim 1 , wherein the surface includes a patterned black mask layer, the method comprising:
 depositing the black mask layer onto a substrate; 
 applying a removable third mask to the black mask layer; and 
 patterning the black mask layer based on the applied third mask. 
 
     
     
       3. The method of  claim 1 , wherein the first conductive layer is a metal layer and the second conductive layer is an indium-tin-oxide layer. 
     
     
       4. The method of  claim 1 , wherein the first conductive layer is an indium-tin-oxide layer and the second conductive layer is a metal layer. 
     
     
       5. The method of  claim 1 , wherein patterning the dielectric layer comprises:
 applying a removable photosensitive mask having a pattern to the dielectric layer; 
 exposing the removable photosensitive mask to light; and 
 developing the dielectric layer to have the pattern of the removable photosensitive mask. 
 
     
     
       6. The method of  claim 1 , wherein the first conductive layer and the dielectric layer have a same pattern. 
     
     
       7. The method of  claim 1 , wherein patterning the passivation layer comprises:
 applying a removable photosensitive mask having a pattern to the passivation layer; 
 exposing the removable photosensitive mask to light; and 
 developing the passivation layer to have the pattern of the removable photosensitive mask. 
 
     
     
       8. The method of  claim 1 , wherein the second conductive layer and the passivation layer have a same pattern. 
     
     
       9. The method of  claim 1 , comprising:
 forming a conductive bridge configured to transmit signals along the first and second conductive layers; and 
 forming a bonding area configured to connect to other circuitry via at least one of the first or second conductive layer. 
 
     
     
       10. A method comprising:
 depositing a first conductive layer onto a surface; 
 patterning a removable photosensitive layer on the first conductive layer; 
 patterning the first conductive layer using the patterned photosensitive layer as a first mask; 
 patterning a black mask layer onto the patterned first conductive layer using a removable second mask; 
 depositing a second conductive layer onto the patterned black mask layer; 
 patterning a passivation layer on the second conductive layer; and 
 patterning the second conductive layer using the patterned passivation layer as a third mask. 
 
     
     
       11. The method of  claim 10 , wherein patterning the removable photosensitive layer comprises developing the photosensitive layer into a pattern of a removable mask. 
     
     
       12. The method of  claim 10 , wherein patterning the first conductive layer comprises forming a same pattern as the patterned photosensitive layer. 
     
     
       13. The method of  claim 10 , wherein patterning the passivation layer comprises developing the passivation layer into a pattern of a removable mask. 
     
     
       14. The method of  claim 10 , wherein patterning the second conductive layer comprises forming a same pattern as the patterned passivation layer. 
     
     
       15. The method of  claim 10 , comprising removing the photosensitive layer. 
     
     
       16. A method comprising:
 depositing a first conductive layer onto a surface; 
 patterning a black mask layer on the first conductive layer; 
 patterning the first conductive layer using the patterned black mask layer as a first mask; 
 depositing a second conductive layer onto the patterned black mask layer; 
 patterning a passivation layer on the second conductive layer; and 
 patterning the second conductive layer using the patterned passivation layer as a second mask. 
 
     
     
       17. The method of  claim 16 , wherein depositing the first conductive layer comprises depositing a conductive layer onto the surface to form a first set of conductive traces and a second set of conductive traces crossing each other, and to form conductive bridges at the crossings of the first and second sets of conductive traces, the first and second sets of conductive traces and the conductive bridges for transmitting signals. 
     
     
       18. The method of  claim 16 , wherein depositing the second conductive layer comprises depositing a metal layer onto the black mask layer to form multiple conductive traces adjacent to each other, the multiple conductive traces for bonding to other circuitry.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application No. 61/235,302, filed Aug. 19, 2009, the contents of which being incorporated herein in their entirety for all purposes. 
    
    
     FIELD 
     This relates generally to thin film patterning, and more particularly, to the simplified patterning of one or more layers of a thin film. 
     BACKGROUND 
     The conventional process for patterning layers on a thin film can require a pattern-forming photo mask for each layer, which can result in a relatively large number of masks. For example, patterning a thin film can including patterning a black mask layer, a metal layer, a dielectric layer, a conductive layer, and a passivation layer, where the black mask layer can require a first photo mask to form its pattern, the metal layer can require a second photo mask to form its pattern, the dielectric layer can require a third photo mask to form its pattern, the conductive layer can require a fourth photo mask to form its pattern, and the passivation layer can require a fifth photo mask to form its pattern. 
     This conventional process can become complex when patterning thin film layers of a touch sensor panel because such patterning can require a photo mask (and sometimes multiple photo masks) for each layer, particularly for patterning conductive drive and sense lines and bonding areas of the panel. Requiring a photo mask for each thin film layer can increase the amount of time needed to form the thin film patterns, the amount of material needed, the amount of equipment needed, the power consumption, the associated costs, and so on. 
     SUMMARY 
     This relates to simplified patterning of layers of a thin film used in devices such as touch sensor panels. The patterning can include patterning a first conductive layer using a patterned dielectric layer as a mask and patterning a second conductive layer using a patterned passivation layer as another mask. In addition or alternatively, the patterning can include patterning a first conductive layer using a removable photosensitive layer as a mask, patterning a black mask layer using a removable photo mask, and patterning a second conductive layer using a patterned passivation layer as another mask. In addition or alternatively, the patterning can include patterning a first conductive layer using a patterned black mask layer as a mask and patterning a second conductive layer using a patterned passivation layer as another mask. This simplified patterning can advantageously realize cost, power, and time savings over the conventional process by providing some patterned layers of a thin film as pattern-forming masks for other layers. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an exemplary touch sensor panel having conductive bridges and bonding areas formed by simplified patterning of thin film layers according to various embodiments. 
         FIGS. 2   a - 2   k  illustrate an exemplary conductive bridge formed by simplified patterning of thin film layers according to various embodiments. 
         FIGS. 3   a - 3   g  illustrate an exemplary bonding area formed by simplified patterning of thin film layers according to various embodiments. 
         FIGS. 4   a - 4   b  illustrate an exemplary patterning of a photosensitive material using an exemplary photo mask according to various embodiments. 
         FIG. 5  illustrates another exemplary photo mask that can be used for patterning of a photosensitive material according to various embodiments. 
         FIGS. 6   a - 6   c  illustrate an exemplary method for simplified patterning of thin film layers of a touch sensor panel according to various embodiments. 
         FIGS. 7   a - 7   j  illustrate a second exemplary conductive bridge formed by simplified patterning of thin film layers according to various embodiments. 
         FIGS. 8   a - 8   f  illustrate a second exemplary bonding area formed by simplified patterning of thin film layers according to various embodiments. 
         FIGS. 9   a - 9   c  illustrate a second exemplary method for simplified patterning of thin film layers of a touch sensor panel according to various embodiments. 
         FIGS. 10   a - 10   j  illustrate a third exemplary conductive bridge formed by simplified patterning of thin film layers according to various embodiments. 
         FIGS. 11   a - 11   f  illustrate a third exemplary bonding area formed by simplified patterning of thin film layers according to various embodiments. 
         FIGS. 12   a - 12   c  illustrate a third exemplary method for simplified patterning of thin film layers of a touch sensor panel according to various embodiments. 
         FIGS. 13   a - 13   i  illustrate a fourth exemplary conductive bridge formed by simplified patterning of thin film layers according to various embodiments. 
         FIGS. 14   a - 14   f  illustrate a fourth exemplary bonding area formed by simplified patterning of thin film layers according to various embodiments. 
         FIGS. 15   a - 15   b  illustrate a fourth exemplary method for simplified patterning of thin film layers of a touch sensor panel according to various embodiments. 
         FIG. 16  illustrates an exemplary mobile telephone having a touch sensor panel that includes conductive bridges and bonding areas formed by simplified patterning of thin film layers according to various embodiments. 
         FIG. 17  illustrates an exemplary digital media player having a touch sensor panel that includes conductive bridges and bonding areas formed by simplified patterning of thin film layers according to various embodiments. 
         FIG. 18  illustrates an exemplary computer having a touch sensor panel that includes conductive bridges and bonding areas formed by simplified patterning of thin film layers according to various embodiments. 
         FIG. 19  illustrates an exemplary computing system including a touch sensor panel utilizing conductive bridges and bonding areas thereon formed by simplified patterning of thin film layers according to various embodiments. 
         FIG. 20  illustrates an exemplary method for simplified patterning of layers of a thin film that can be used in an electronic device according to various embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description of various embodiments, reference is made to the accompanying drawings which form a part hereof, and in which it is shown by way of illustration specific embodiments which may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the various embodiments. 
     This relates to patterning of thin film conductive and passivation layers, which can be simpler than patterning in a conventional process. This patterning can be used for touch sensor panels to form conductive bridges between drive and sense conductive traces and to form bonding areas to connect the panel to other circuitry. In some embodiments, the patterning can include patterning a first conductive layer using a patterned dielectric layer as a mask and patterning a second conductive layer using a patterned passivation layer as another mask. In other embodiments, the patterning can include patterning a first conductive layer using a removable photosensitive layer as a mask, patterning a black mask layer using a removable photo mask, and patterning a second conductive layer using a patterned passivation layer as another mask. In still other embodiments, the patterning can include patterning a first conductive layer using a patterned black mask layer as a mask and patterning a second conductive layer using a patterned passivation layer as another mask. 
     This simplified patterning can advantageously reduce the number of photo masks from that required by the conventional process. Rather, some of the patterned layers can function as masks for underlying layers. This simplified patterning can also reduce the actions required by the conventional process, including mask removal and photosensitive layer deposition, in some instances. Accordingly, this simplified patterning can save cost, power, and time over the conventional process. 
     Although various embodiments are described and illustrated herein in terms of touch sensor panels, it should be understood that the embodiments are not so limited to such panels, but are generally applicable to panels utilizing other touch and proximity sensing technologies, and any device for which thin film layer patterning can be applied. 
       FIG. 1  illustrates an exemplary touch sensor panel having conductive bridges and bonding areas formed by simplified patterning of thin film layers according to various embodiments. In the example of  FIG. 1 , touch sensor panel  100  can include touch area  110 . The touch area  110  can include multiple row conductive traces  112  and column conductive traces  114 , forming touch sensors that can be used to sense a touch at the touch area. The row traces  112  and the column traces  114  can be formed to cross each other on a thin film. To minimize physical contact between the traces  112 ,  114  which could adversely affect operation of the panel  100 , conductive bridge  120  can be formed at each crossing. The conductive bridge  120  can include one or more thin film layers, including a black mask layer, a metal layer, a dielectric layer, a conductive layer, and/or a passivation layer. The black mask layer can include a black material, e.g., carbon black, titanium black, and the like, and a polymer material, e.g., molybdenum, polyamide, and the like, to provide a cosmetic, aesthetic look of the panel  100 . In some embodiments, the black mask layer can be a photosensitive material. The metal layer can include a sufficiently conductive metal to conduct electrical signals. The dielectric layer can include a dielectric material to insulate conductive components of the panel  100 . In some embodiments, the dielectric layer can be a photosensitive material. The conductive layer can include a conductive material, e.g., indium-tin-oxide (ITO), to conduct electrical signals. The passivation layer can include a polymer material, e.g., polyamide and the like, to protect underlying material, such as the metal layer, from damage that could be caused by the environment or downstream processes. In some embodiments, the passivation layer can be a photosensitive material. The conductive bridge  120  can be formed using simplified patterning of the thin film layers according to various embodiments. Example conductive bridge formations will be described later. 
     In operation, the conductive bridge  120  can conduct electrical signals along crossing row trace  112  and column trace  114  without the signals interacting in a way that could adversely affect the touch panel operation. The row conductive trace  112  can conduct electrical signals along one path of the conductive bridge  120 , for example, along a lower portion of the bridge, to drive the touch sensor panel  100 . The column conductive trace  114  can conduct electrical signals along another path of the conductive bridge  120 , for example, along an upper portion of the bridge, to transmit signals indicative of a touch at the panel  100 . Alternatively, the column trace  114  can conduct drive signals and the row trace  112  can conduct touch signals and/or the column trace can conduct along the lower portion of the bridge and the row trace can conduct along the upper portion of the bridge. 
     The touch sensor panel  100  can also include bonding area  130 . The bonding area  130  can include multiple bonding conductive traces  136 , forming input/output connections for other circuitry, e.g., flex circuits, controllers, processors, and the like, to bond to the touch sensor panel  100 . The conductive traces  116  can be formed near a boundary of a thin film in parallel or near parallel lines, for example. The bonding area  130  can include one or more thin film layers, including a black mask layer, a metal layer, and/or a conductive layer. So that the bonding traces  136  can electrically connect with other circuitry, the metal layer and/or the conductive layer can be exposed on the thin film. The bonding area  130  can be formed using simplified patterning of thin film layers according to various embodiments. Example bonding area formations will be described later. 
     In operation, the bonding area  130  can conduct electrical signals back and forth along the bonding traces  136  between the touch sensor panel  100  and other circuitry. Example signals can include the touch signals from the touch area  110 , commands from a controller to search for a touch, and so on. 
     It is to be understood that the touch sensor panel of  FIG. 1  is not limited to that shown, but can include other components, configurations, and operations according to various embodiments. 
       FIGS. 2   a - 2   k  illustrate an exemplary conductive bridge of a touch sensor panel formed by simplified patterning of thin film layers according to various embodiments.  FIGS. 2   d ( ii ),  2   f ( ii ), and  2   g ( ii ) illustrate transversal cross sections of conductive bridge  200  and the remaining FIGs. illustrate longitudinal cross sections of the bridge. In the example of  FIG. 2   a , black mask layer  202  can be patterned onto a thin film substrate. The black mask layer  202  can be patterned, for example, by coating the thin film substrate with a black mask material, applying a removable photo mask to the black mask material, exposing the applied photo mask to light, and developing the black mask material into the pattern of the applied photo mask. Photo masks will be described in more detail later in  FIGS. 4   a - 4   b  and  5 . In the example of  FIG. 2   b , metal layer  204  can be deposited on the patterned black mask layer  202  and dielectric layer  206  can coat the metal layer at thickness t o . In the example of  FIG. 2   c , the dielectric layer  206  can be patterned on the metal layer  204  to have first thickness t 1  near the center portion of the pattern and second thickness t 2  near the edge portions of the pattern, where t o &gt;t 1 &gt;t 2 . The dielectric layer  206  can be patterned, for example, by exposing an applied photo mask to light and developing the dielectric layer into the pattern of the applied photo mask. In the example of  FIGS. 2   d ( i ) (the longitudinal cross section) and  2   d ( ii ) (the transversal cross section), the metal layer  204  can be etched. Here, rather than using a photo mask as in the conventional process, the patterned dielectric layer  206  can function as an etching mask for the underlying metal layer  204 , resulting in a simplified patterning. In the example of  FIG. 2   e , the t 2 -thickness portions of the dielectric layer  206  can be removed and the t 1 -thickness portion can be reduced to thickness t 3 , where t 1 &gt;t 3 &gt;t 2 . This can be done, for example, by ashing using oxygen plasma. 
     In the example of  FIGS. 2   f ( i ) (the longitudinal cross section) and  2   f ( ii ) (the transversal cross section), the dielectric layer  206  can be cured to thickness t 4 , where t 3 &gt;t 4 . During curing, the dielectric layer  206  can be heated to a temperature at which the layer becomes soft and flows over the underlying metal layer  204  along a transversal profile, as shown in  FIG. 2   f ( ii ). In the example of  FIGS. 2   g (i) (the longitudinal cross section) and  2   g (ii) (the transversal cross section), conductive layer  208  can be deposited over the cured dielectric layer  206 . In the example of  FIG. 2   h , passivation layer  210  can coat the conductive layer  208 . The passivation layer  210  can have thickness t o  and can be a photosensitive material and either organic or inorganic. In the example of  FIG. 2   i , the passivation layer  210  can be developed into a pattern having portions of the layer removed to form a center portion having thickness t 2  and to form left and right portions having thickness t 1  near the center portion and thickness t 2  farther away, where t o &gt;t 1 &gt;t 2 . The passivation layer  210  can be patterned by, for example, exposing an applied photo mask to light and developing the passivation layer into the pattern of the applied photo mask. In the example of  FIG. 2   j , the conductive layer  208  can be etched to form left and right portions that can be a row trace and a center portion that can be a column trace. Here, rather than using a photo mask as in the conventional process, the patterned passivation layer  210  can function as the etching mask for the conductive layer  208 , resulting in a simplified patterning. In the example of  FIG. 2   k , excess passivation layer  210  can be removed, e.g., by ashing using oxygen plasma, such that the t 2 -thickness portions of the layer can be removed and the tj-thickness portions can be reduced to thickness t 3 , where t 1 &gt;t 3 &gt;t 2 . The resulting conductive bridge  200  can transmit electrical signals of a touch sensor panel, as described previously. 
       FIGS. 3   a - 3   g  illustrate an exemplary bonding area of a touch sensor panel formed by simplified patterning of thin film layers according to various embodiments. In the example of  FIG. 3   a , black mask layer  302  can be deposited on a thin film substrate. In the example of  FIG. 3   b , metal layers  304  can be patterned onto the black mask layer  302 . The metal layers  304  can be patterned, for example, by depositing the metal material on the black mask layer, applying a removable photo mask to the metal material, exposing the applied photo mask to light, and developing the metal material into the pattern of the applied photo mask. In the example of  FIG. 3   c , conductive layer  308  can be deposited over the metal layers  304 . In the example of  FIG. 3   d , passivation layer  310  can be deposited on the conductive layer  308  and can have thickness t o . In the example of  3   e , the passivation layer  310  can be developed into a pattern having separate portions with thickness t 3 , where to &gt;t 3 . The passivation layer  310  can be patterned, for example, by exposing an applied photo mask to light and developing the passivation layer into the pattern of the applied photo mask. In the example of  FIG. 3   f , the conductive layer  308  can be etched to form a pattern for bonding conductive traces. Here, rather than using a photo mask as in the conventional process, the patterned passivation layer  310  can function as the etching mask for the conductive layer  308 , resulting in a simplified patterning. In the example of  FIG. 3   g , the remaining passivation layer  310  can be removed, e.g., by ashing, such that the conductive layer  308  can be available for bonding with other circuitry. 
     The simplified patterning of  FIGS. 2   a - 2   k  and  3   a - 3   g  can be performed concurrently. The black mask layers  202 ,  302  can be deposited onto the thin film substrate as in  FIGS. 2   a  and  3   a . The metal layers  204 ,  304  can be deposited onto the black mask layers  202 ,  302  as in  FIGS. 2   b  and  3   b . The dielectric layer  206  can be deposited onto the metal layer  204  as in  FIG. 2   b . The dielectric layer  206  and the metal layer  204  can be patterned as in  FIGS. 2   c - 2   f . The conductive layers  208 ,  308  can be deposited as in  FIGS. 2   g  and  3   c . The passivation layers  210 ,  310  can be deposited with thickness t o  as in  FIGS. 2   h  and  3   d . The passivation layers  210 ,  310  can be patterned as in  FIGS. 2   i  and  3   e . The conductive layers  208 ,  308  can be etched to form conductive patterns as in  FIGS. 2   j  and  3   f . Excess portions of the passivation layer  210 ,  310  can be removed as in  FIGS. 2   k  and  3   g . In this simplified patterning, the number of removable photo masks could be reduced from at least five, as in the conventional process, to no more than three (e.g., for black mask, dielectric, and passivation layer patterning). 
     It is to be understood that patterning is not limited to that illustrated here, but can include other and/or additional components according to various embodiments. 
     It is further to be understood that the black mask layers  202 ,  302  can be optional. As such, the conductive bridge and the bonding area can be formed, beginning with a metal layer deposited on a thin film substrate. Examples of thin film layers without black mask layers are described in U.S. patent application Ser. No. 12/501,390, entitled “Patterning of Thin Film Conductive and Passivation Layers,” the contents of which being incorporated by reference herein for all purposes. 
       FIGS. 4   a - 4   b  illustrate an exemplary patterning of a photosensitive material using an exemplary photo mask according to various embodiments. In the example of  FIG. 4   a , photo mask  402  can include portions having various transparencies (also known as a half-tone mask). In this example, portion P 1  can be black or non-transparent, portion P 2  can be clear or transparent, and portion P 3  can be gray or semi-transparent. The amount of transparency of each portion can determine the light intensity transmitted through that portion of the photo mask  402 . Here, the photo mask  402  can be exposed to light having an intensity I o . Because portion P 1  is non-transparent, this portion can not transmit any of the light. Because portion P 2  is transparent, this portion can transmit light at an intensity I 2  close to the original intensity I o , where I 2 &lt;I o . Because portion P 3  is semi-transparent, this portion can transmit light at a lower intensity I 3  than either I 2  or I o , where 0&lt;I 3 &lt;I 2 &lt;I o . Photosensitive material  404  can have an initial thickness t a . When the light at various intensities hit the photosensitive material  404 , the light can trigger a chemical reaction of the material proportionate to the light&#39;s intensity, thereby eliminating the reacting material. This can be known as “developing” the photosensitive material. 
       FIG. 4   b  illustrates an example of the photosensitive material  404  after it has been developed after being exposed to light through the photo mask  402 . Here, the material  404  proximate to portion P 1  of the photo mask  402  retained its thickness t a  because it was not exposed to any light and therefore did not react. The material  404  proximate to portion P 2  of the photo mask  402  was eliminated (indicated by t b ) because it was exposed to enough light to react all of the material. The material  404  proximate to portion P 3  of the photo mask  402  reduced its thickness to t o  because it was exposed to sufficient light to partially react. 
       FIG. 5  illustrates another exemplary photo mask that can be used for patterning of a photosensitive material according to various embodiments. In the example of  FIG. 5 , photo mask  502  can include portions having various slit densities (also known as a slit mask), rather than various transparencies as in  FIG. 4   a . In this example, portion P 1  can have no slits, allowing no light to penetrate the portion. Portion P 2  can have a high slit density, allowing substantial light to penetrate the portion. Portion P 3  can have a sparser slit density, allowing moderate light to penetrate the portion. The photo mask  502  can affect a photosensitive material similarly as described above. 
       FIGS. 6   a - 6   c  illustrate an exemplary method for simplified patterning of thin film layers of a touch sensor panel according to various embodiments. This method can be used to form the conductive bridge of  FIGS. 2   a - 2   k  and the bonding area of  FIGS. 3   a - 3   g . In the example of  FIG. 6   a , a black mask (BM) layer can be deposited onto a base substrate ( 600 ). A removable photo mask can be applied to the black mask layer, where the photo mask can include the desired pattern for the black mask ( 602 ). The black mask layer can be exposed to light through the photo mask ( 604 ). The black mask layer can be developed to have the desired pattern ( 606 ). The patterned black mask layer can be cured ( 608 ). 
     In the example of  FIG. 6   b , a metal layer can be deposited onto the patterned black mask ( 620 ). The metal layer can be coated with a dielectric layer ( 622 ). A removable photo mask can be applied to the dielectric layer, where the photo mask can include the desired pattern for metal layer ( 624 ). The dielectric layer can be exposed to light through the photo mask ( 626 ). The dielectric layer can be developed to have the desired pattern ( 628 ). The metal layer can be etched using the patterned dielectric layer as its etching mask ( 630 ). This eliminates requiring another removable mask for the metal layer as in the conventional process, thereby simplifying the patterning. The dielectric layer can be ashed to remove any excess portions ( 632 ). The dielectric layer can be cured to soften and flow over the metal layer according to a desired profile ( 634 ). 
     In the example of  FIG. 6   c , a conductive layer can be deposited over the dielectric layer ( 640 ). The conductive layer can be coated with a passivation layer ( 642 ). A removable photo mask can be applied over the passivation layer, where the photo mask can include the desired pattern for the conductive layer ( 644 ). The passivation layer can be exposed to light through the photo mask ( 646 ). The passivation layer can be developed to have the desired pattern ( 648 ). The conductive layer can be etched using the patterned passivation layer as its etching mask ( 650 ). This eliminates requiring an additional removable mask for the conductive layer as in the conventional process, thereby further simplifying the patterning. Excess portions of the passivation layer can be removed by ashing ( 652 ). In the case of the bonding area or other conductive traces that should be exposed, all of the passivation layer can be removed from the conductive layer. In the case of the conductive bridge or other conductive traces that should be protected, some or none of the passivation layer can be removed from the conductive layer. The remaining portions of the passivation layer can be cured ( 654 ). 
     It is to be understood that the method is not limited to that described in  FIGS. 6   a - 6   c , but can include other or additional actions for simplified patterning of thin film layers. In some embodiments, the black mask layer can be omitted, such that the method can include the actions of  FIGS. 6   b - 6   c.    
       FIGS. 7   a - 7   j  illustrate an exemplary conductive bridge of a touch sensor panel formed by simplified patterning of thin film layers according to various embodiments. In the example of  FIG. 7   a , black mask layer  702  can be patterned onto a thin film substrate. The black mask layer  702  can be patterned, for example, by coating the thin film substrate with a black mask material, applying a removable photo mask, as in  FIGS. 4   a - 4   b  and  5 , to the black mask material, exposing the applied photo mask to light, and developing the black mask material into the pattern of the applied photo mask. In the example of  FIG. 7   b , conductive layer  708  can be deposited on the patterned black mask layer  702  and dielectric layer  706  can coat the conductive layer. The dielectric layer  706  can have thickness t o . In the example of  FIG. 7   c , the dielectric layer  706  can be patterned on the conductive layer  708  to have first thickness t 1  near the center portion of the pattern and second thickness t 2  near the edge portions of the pattern, where t o &gt;t 1 &gt;t 2 . The dielectric layer  706  can also be patterned to eliminate some portions around the center portion. Then the conductive layer  708  can be etched to form left and right portions that can be a row trace and a center portion that can be a column trace. Here, rather than using a removable photo mask as in the conventional process, the patterned dielectric layer  706  can function as an etching mask for the underlying conductive layer  708 , resulting in a simplified patterning. As shown, the portions of the conductive layer  708  having had the dielectric layer  706  removed were the portions of the conductive layer that were etched away. In the example of  FIG. 7   d , the t 2 -thickness portions of the dielectric layer  706  can be removed and the t 1 -thickness portion can be reduced to thickness t 3 , where t 1 &gt;t 3 &gt;t 2 . This can be done, for example, by ashing the dielectric layer  706  using oxygen plasma. In the example of  FIG. 7   e , the dielectric layer  706  can be cured to thickness t 4 , where t 3 &gt;t 4 . During curing, the dielectric layer  706  can be heated to a temperature at which the layer becomes soft and flows over the underlying conductive layer  708 . 
     In the example of  FIG. 7   f , metal layer  704  can be deposited over the cured dielectric layer  706  and the conductive layer  708 . In the example of  FIG. 7   g , passivation layer  710  can coat the metal layer  704 . The passivation layer  710  can have thickness t o  and can be a photosensitive material and either organic or inorganic. In the example of  FIG. 7   h , the passivation layer  710  can be developed into a pattern having portions of the layer removed to form a center portion having thickness t 1 , where t o &gt;t 1 . The passivation layer  710  can be patterned by, for example, exposing an applied photo mask to light and developing the passivation layer into the pattern of the applied photo mask. In the example of  FIG. 7   i , the metal layer  704  can be etched to form a center portion below the patterned passivation layer  710  that can connect to the left and right portions of the conductive layer  708 . Here, rather than using a removable photo mask as in the conventional process, the patterned passivation layer  710  can function as the etching mask for the metal layer  704 , resulting in a simplified patterning. Excess portions of the passivation layer  710  can be removed, e.g., by ashing using oxygen plasma, reducing the thickness of the layer to t 3 , where t 1 &gt;t 3 . In the example of  FIG. 7   j , the remaining passivation layer  710  can be cured to thickness t 4 , where t 3 &gt;t 4 . During curing, the passivation layer  710  can be heated to a temperature at which the layer becomes soft and flows over the underlying metal layer  704 . The resulting conductive bridge  700  can transmit electrical signals of a touch sensor panel, as described previously. 
       FIGS. 8   a - 8   f  illustrate an exemplary bonding area of a touch sensor panel formed by simplified patterning of thin film layers according to various embodiments. In the example of  FIG. 8   a , black mask layer  802  can be deposited on a thin film substrate. In the example of  FIG. 8   b , metal layer  804  can be deposited onto the black mask layer  802 . In the example of  FIG. 8   c , passivation layer  810  can be deposited on the metal layer  804  and can have thickness t o . In the example of  8   d , the passivation layer  810  can be developed into a pattern having separate portions with thickness t 3 , where t o &gt;t 3 . The passivation layer  810  can be patterned, for example, by exposing an applied photo mask to light and developing the passivation layer into the pattern of the applied photo mask. In the example of  FIG. 8   e , the metal layer  804  can be etched to form a pattern for bonding conductive traces. Here, rather than using a removable photo mask as in the conventional process, the patterned passivation layer  810  can function as the etching mask for the metal layer  804 , resulting in a simplified patterning. In the example of  FIG. 8   f , the remaining passivation layer  810  can be removed, e.g., by ashing, such that the metal layer  804  can be exposed for bonding with other circuitry. 
     The simplified patterning of  FIGS. 7   a - 7   j  and  8   a - 8   f  can be performed concurrently. The black mask layers  702 ,  802  can be deposited onto the thin film substrate as in  FIGS. 7   a  and  8   a . The conductive layer  708  and the dielectric layer  706  can be deposited and patterned as in  FIGS. 7   b - 7   e . The metal layers  704 ,  804  can be deposited as in  FIGS. 7   f  and  8   b . The passivation layers  710 ,  810  can be deposited with thickness t o  as in  FIGS. 7   g  and  8   c . The passivation layers  710 ,  810  can be patterned as in  FIGS. 7   h  and  8   d . The metal layers  704 ,  804  can be etched as in  FIGS. 7   i  and  8   e . Excess portions of the passivation layer  710 ,  810  can be removed as in  FIGS. 7   i - 7   j  and  8   f . In this simplified patterning, the number of removable photo masks could be reduced from at least five, as in the conventional process, to no more than three (e.g., for black mask, dielectric, and passivation layer patterning). 
     It is to be understood that patterning is not limited to that illustrated here, but can include other and/or additional components according to various embodiments. 
     It is further to be understood that the black mask layers  702 ,  802  can be optional. As such, the conductive bridge and the bonding area can be formed, beginning with a metal layer deposited on a thin film substrate. 
       FIGS. 9   a - 9   c  illustrate an exemplary method for simplified patterning of thin film layers of a touch sensor panel according to various embodiments. This method can be used to form the conductive bridge of  FIGS. 7   a - 7   j  and the bonding area of  FIGS. 8   a - 8   f . In the example of  FIG. 9   a , a black mask (BM) layer can be deposited onto a base substrate ( 900 ). A removable photo mask can be applied to the black mask layer, where the photo mask can include the desired pattern for the black mask ( 902 ). The black mask layer can be exposed to light through the photo mask ( 904 ). The black mask layer can be developed to have the desired pattern ( 906 ). The patterned black mask layer can be cured ( 908 ). 
     In the example of  FIG. 9   b , a conductive layer can be deposited onto the patterned black mask ( 920 ). The conductive layer can be coated with a dielectric layer ( 922 ). A removable photo mask can be applied to the dielectric layer, where the photo mask can include the desired pattern for the conductive layer ( 924 ). The dielectric layer can be exposed to light through the photo mask ( 926 ). The dielectric layer can be developed to have the desired pattern ( 928 ). The conductive layer can be etched using the patterned dielectric layer as its etching mask ( 930 ). This eliminates requiring another removable mask for the conductive layer as in the conventional process, thereby simplifying the patterning. The dielectric layer can be ashed to remove any excess portions ( 932 ). The dielectric layer can be cured to soften and flow over the conductive layer according to a desired profile ( 934 ). 
     In the example of  FIG. 9   c , a metal layer can be deposited over the dielectric layer and the conductive layer ( 940 ). The metal layer can be coated with a passivation layer ( 942 ). A removable photo mask can be applied over the passivation layer, where the photo mask can include the desired pattern for the metal layer ( 944 ). The passivation layer can be exposed to light through the photo mask ( 946 ). The passivation layer can be developed to have the desired pattern ( 948 ). The metal layer can be etched using the patterned passivation layer as its etching mask ( 950 ). This eliminates requiring an additional removable mask for the metal layer as in the conventional process, thereby further simplifying the patterning. Excess portions of the passivation layer can be removed by ashing ( 952 ). In the case of the bonding area or other conductive traces that should be exposed, all of the passivation layer can be removed from the metal layer. In the case of the conductive bridge or other conductive traces that should be protected, some or none of the passivation layer can be removed from the conductive layer. The remaining portions of the passivation layer can be cured ( 954 ). 
     It is to be understood that the method is not limited to that described in  FIGS. 9   a - 9   c , but can include other or additional actions for simplified patterning of thin film layers. In some embodiments, the black mask layer can be omitted, such that the method can include the actions of  FIGS. 9   b - 9   c.    
       FIGS. 10   a - 10   j  illustrate an exemplary conductive bridge of a touch sensor panel formed by simplified patterning of thin film layers according to various embodiments. In the example of  FIG. 10   a , conductive layer  1008  can be deposited onto a thin film substrate. In the example of  FIG. 10   b , the conductive layer  1008  can be coated with photosensitive (or photoresist) layer  1012 . In the example of  FIG. 10   c , the photosensitive layer  1012  can be patterned to have a desired pattern of the conductive layer  1008 . The photosensitive layer  1012  can be patterned, for example, by applying a removable photo mask, as in  FIGS. 4   a - 4   b  and  5 , to the layer, exposing the applied photo mask to light, and developing the photosensitive layer into the pattern of the mask. In the example of  FIG. 10   d , the conductive layer  1008  can be etched to form left and right portions that can be a row trace and a center portion that can be a column trace. Here, rather than using a removable photo mask as in the conventional process, the patterned photosensitive layer  1012  can function as an etching mask for the underlying conductive layer  1008 , resulting in a simplified patterning. As shown, the portions of the conductive layer  1008  having had the photosensitive layer  1012  removed were the portions of the conductive layer that were etched away. The remaining photosensitive layer  1012  can be removed from the conductive layer  1008 , for example, by chemical stripping. In the example of  FIG. 10   e , black mask layer  1002  can be deposited on the patterned conductive layer  1008 . In the example of  FIG. 10   f , the black mask layer  1002  can be patterned. The black mask layer  1002  can be patterned, for example, by applying a removable photo mask, as in  FIGS. 4   a - 4   b  and  5 , to the black mask material, exposing the applied photo mask to light, and developing the black mask material into the pattern of the applied photo mask. The patterned black mask layer  1002  can be cured. 
     In the example of  FIG. 10   g , metal layer  1004  can be deposited on the patterned black mask layer  1002  and passivation layer  1010  can coat the metal layer. The passivation layer  1010  can have thickness t o . In the example of  FIG. 10   h , the passivation layer  1010  can be patterned on the metal layer  1004  to have thickness t 1 , where t o &gt;t 1 . The passivation layer  1010  can be patterned by, for example, exposing an applied photo mask to light and developing the passivation layer into the pattern of the applied photo mask. In the example of  FIG. 10   i , the metal layer  1004  can be etched to form a center portion below the patterned passivation layer  1010  that can connect to the left and right portions of the conductive layer  1008 . Here, rather than using a removable photo mask as in the conventional process, the patterned passivation layer  1010  can function as the etching mask for the metal layer  1004 , resulting in a simplified patterning. In the example of  FIG. 10   j , the passivation layer  1010  can be cured to thickness t 4 , where t 1 &gt;t 4 . During curing, the passivation layer  1010  can be heated to a temperature at which the layer becomes soft and flows over the underlying metal layer  1004 . The resulting conductive bridge  1000  can transmit electrical signals of a touch sensor panel, as described previously. 
       FIGS. 11   a - 11   f  illustrate an exemplary bonding area of a touch sensor panel formed by simplified patterning of thin film layers according to various embodiments. In the example of  FIG. 11   a , black mask layer  1102  can be deposited on a thin film substrate. In the example of  FIG. 11   b , metal layer  1104  can be deposited onto the black mask layer  1102 . In the example of  FIG. 11   c , passivation layer  1110  can be deposited on the metal layer  1104  and can have thickness t o . In the example of  11   d , the passivation layer  1110  can be developed into a pattern having separate portions with thickness t 3 , where t o &gt;t 3 . The passivation layer  1110  can be patterned, for example, by exposing an applied photo mask to light and developing the passivation layer into the pattern of the applied photo mask. In the example of  FIG. 11   e , the metal layer  1104  can be etched to form a pattern for bonding conductive traces. Here, rather than using a removable photo mask as in the conventional process, the patterned passivation layer  1110  can function as the etching mask for the metal layer  1104 , resulting in a simplified patterning. In the example of  FIG. 11   f , the remaining passivation layer  1110  can be removed, e.g., by ashing, such that the metal layer  1104  can be exposed for bonding with other circuitry. 
     The simplified patterning of  FIGS. 10   a - 10   j  and  11   a - 11   f  can be performed concurrently. The conductive layer  1008  and the photosensitive layer  1012  can be deposited and patterned onto the thin film substrate as in  FIGS. 10   a - 10   d . The black mask layers  1002 ,  1102  can be deposited as in  FIGS. 10   e  and  11   a . The black mask layer  1002  can be patterned as in  FIG. 10   f . The metal layers  1004 ,  1104  can be deposited and the passivation layers  1010 ,  1110  can be deposited with thickness t o  as in  FIGS. 10   g  and  11   b - 11   c . The passivation layers  1010 ,  1110  can be patterned as in  FIGS. 10   h  and  11   d . The metal layers  1004 ,  1104  can be etched as in  FIGS. 10   i  and  11   e . The passivation layer  1110  can be removed from the bonding areas as in  FIG. 11   f . The passivation layer  1010  on the conductive bridge can be cured as in  FIG. 10   j . In this simplified patterning, the number of removable photo masks could be reduced from at least five, as in the conventional process, to no more than three (e.g., for photosensitive, black mask, and passivation layer patterning). 
     It is to be understood that patterning is not limited to that illustrated here, but can include other and/or additional components according to various embodiments. In some embodiments, the black mask layer can be replaced by a dielectric layer. In some embodiments, a combination black mask and dielectric layer can be used. 
       FIGS. 12   a - 12   c  illustrate an exemplary method for simplified patterning of thin film layers of a touch sensor panel according to various embodiments. This method can be used to form the conductive bridge of  FIGS. 10   a - 10   j  and the bonding area of  FIGS. 11   a - 11   f . In the example of  FIG. 12   a , a conductive layer can be deposited onto a base substrate ( 1200 ). The conductive layer can be coated with a photosensitive (or photoresist) layer ( 1202 ). A removable photo mask can be applied to the photosensitive layer, where the photo mask can include the desired pattern for the conductive layer ( 1204 ). The photosensitive layer can be exposed to light through the photo mask ( 1206 ). The photosensitive layer can be developed to have the desired pattern ( 1208 ). The conductive layer can be etched using the patterned photosensitive layer as its etching mask ( 1210 ). This eliminates the need for another removable mask for the conductive layer as in the conventional process, thereby simplifying the patterning. The photosensitive layer can be chemically stripped to remove it from the patterned conductive layer ( 1212 ). 
     In the example of  FIG. 12   b , a black mask (BM) layer can be deposited onto the patterned conductive layer ( 1220 ). A removable photo mask can be applied to the black mask layer, where the photo mask can include the desired pattern for the black mask ( 1222 ). The black mask layer can be exposed to light through the photo mask ( 1224 ). The black mask layer can be developed to have the desired pattern ( 1226 ). The patterned black mask layer can be cured ( 1228 ). 
     In the example of  FIG. 12   c , a metal layer can be deposited over the black mask layer and the conductive layer ( 1240 ). The metal layer can be coated with a passivation layer ( 1242 ). A removable photo mask can be applied over the passivation layer, where the photo mask can include the desired pattern for the metal layer ( 1244 ). The passivation layer can be exposed to light through the photo mask ( 1246 ). The passivation layer can be developed to have the desired pattern ( 1248 ). The metal layer can be etched using the patterned passivation layer as its etching mask ( 1250 ). This eliminates the need for an additional removable mask for the metal layer as in the conventional process, thereby further simplifying the patterning. Excess portions of the passivation layer can be removed by ashing ( 1252 ). In the case of the bonding area or other conductive traces that should be exposed, all of the passivation layer can be removed from the metal layer. In the case of the conductive bridge or other conductive traces that should be protected, some or none of the passivation layer can be removed from the conductive layer. The remaining portions of the passivation layer can be cured ( 1254 ). 
     It is to be understood that the method is not limited to that described in  FIGS. 12   a - 12   c , but can include other or additional actions for simplified patterning of thin film layers. 
       FIGS. 13   a - 13   i  illustrate an exemplary conductive bridge of a touch sensor panel formed by simplified patterning of thin film layers according to various embodiments. In the example of  FIG. 13   a , conductive layer  1308  can be deposited onto a thin film substrate. In the example of  FIG. 13   b , the conductive layer  1308  can be coated with black mask (BM) layer  1302  having thickness t o . In the example of  FIG. 13   c , the black mask layer  1302  can be patterned to have a desired pattern of the conductive layer  1308 , where the black mask layer can have portions removed to form a center portion having first thickness t 1  and left and right portions having second thickness t 2  proximate to the center portion, where t o &gt;t 1 &gt;t 2 . The black mask layer  1302  can be patterned, for example, by applying a removable photo mask, as in  FIGS. 4   a - 4   b  and  5 , to the layer, exposing the applied photo mask to light, and developing the black mask layer into the pattern of the photo mask. In the example of  FIG. 13   d , the conductive layer  1308  can be etched to form left and right portions that can be a row trace and a center portion that can be a column trace. Here, rather than using a removable photo mask as in the conventional process, the patterned black mask layer  1302  can function as an etching mask for the underlying conductive layer  1308 , resulting in a simplified patterning. As shown, the portions of the conductive layer  1308  having had the black mask layer  1302  removed were the portions of the conductive layer that were etched away. In the example of  FIG. 13   e , excess portions of the black mask layer  1302  can be removed, for example, by ashing, resulting in the t 2 -thickness portions being eliminated and the t 1 -thickness portion being decreased. The ashed black mask layer  1302  can be cured to thickness t 4 , where t 1 &gt;t 4 . During curing, the black mask layer  1302  can be heated to a temperature at which the layer becomes soft and flows over the underlying conductive layer  1008 . 
     In the example of  FIG. 13   f , metal layer  1304  can be deposited on the patterned black mask layer  1302  and the conductive layer  1308 . Passivation layer  1310  can coat the metal layer  1302  with thickness t o . In the example of  FIG. 13   g , the passivation layer  1310  can be patterned on the metal layer  1304  to have thickness t 1 , where t o &gt;t 1 . The passivation layer  1310  can be patterned by, for example, exposing an applied photo mask to light and developing the passivation layer into the pattern of the applied photo mask. In the example of  FIG. 13   h , the metal layer  1304  can be etched to form a center portion below the patterned passivation layer  1310  connecting to the left and right portions of the conductive layer  1308 . Here, rather than using a removable photo mask as in the conventional process, the patterned passivation layer  1310  can function as the etching mask for the metal layer  1304 , resulting in a simplified patterning. In the example of  FIG. 13   i , the passivation layer  1310  can be cured to thickness t 4 , where t 1 &gt;t 4 . During curing, the passivation layer  1310  can be heated to a temperature at which the layer becomes soft and flows over the underlying metal layer  1304 . The resulting conductive bridge  1300  can transmit electrical signals of a touch sensor panel, as described previously. 
       FIGS. 14   a - 14   f  illustrate an exemplary bonding area of a touch sensor panel formed by simplified patterning of thin film layers according to various embodiments. In the example of  FIG. 14   a , conductive layer  1408  and black mask layer  1402  can be deposited on a thin film substrate. In the example of  FIG. 14   b , metal layer  1404  can be deposited onto the black mask layer  1402 . In the example of  FIG. 14   c , passivation layer  1410  can be deposited on the metal layer  1404  and can have thickness t o . In the example of  14   d , the passivation layer  1410  can be developed into a pattern having separate portions with thickness t 3 , where t o &gt;t 3 . The passivation layer  1410  can be patterned, for example, by exposing an applied photo mask to light and developing the passivation layer into the pattern of the applied photo mask. In the example of  FIG. 14   e , the metal layer  1404  can be etched to form a pattern for bonding conductive traces. Here, rather than using a removable photo mask as in the conventional process, the patterned passivation layer  1410  can function as the etching mask for the metal layer  1404 , resulting in a simplified patterning. In the example of  FIG. 14   f , the remaining passivation layer  1410  can be removed, e.g., by ashing, such that the metal layer  1404  can be exposed for bonding with other circuitry. 
     The simplified patterning of  FIGS. 13   a - 13   i  and  14   a - 14   f  can be performed concurrently. The conductive layers  1308 ,  1408  and the black mask layers  1302 ,  1402  can be deposited onto the thin film substrate as in  FIGS. 13   a - 13   b  and  14   a . The black mask layer  1302  and the conductive layer  1308  can be patterned as in  FIGS. 13   c - 13   e . The metal layers  1304 ,  1404  can be deposited and the passivation layers  1310 ,  1410  can be deposited with thickness t o  as in  FIGS. 13   f  and  14   b - 14   c . The passivation layers  1310 ,  1410  can be patterned as in  FIGS. 13   g  and  14   d . The metal layers  1304 ,  1404  can be etched as in  FIGS. 13   h  and  14   e . The passivation layer  1410  can be removed from the bonding areas as in  FIG. 14   f . The passivation layer  1310  on the conductive bridge can be cured as in  FIG. 13   i . In this simplified patterning, the number of removable photo masks could be reduced from at least five, as in the conventional process, to no more than two (e.g., for black mask and passivation layer patterning). 
     It is to be understood that patterning is not limited to that illustrated here, but can include other and/or additional components according to various embodiments. In some embodiments, the black mask layer can be replaced by a dielectric layer. In some embodiments, a combination black mask and dielectric layer can be used. 
       FIGS. 15   a - 15   b  illustrate an exemplary method for simplified patterning of thin film layers of a touch sensor panel according to various embodiments. This method can be used to form the conductive bridge of  FIGS. 13   a - 13   i  and the bonding area of  FIGS. 14   a - 14   f . In the example of  FIG. 15   a , a conductive layer can be deposited onto a base substrate ( 1500 ). The conductive layer can be coated with a black mask (BM) layer ( 1502 ). A removable photo mask can be applied to the black mask layer, where the photo mask can include the desired pattern for the conductive layer ( 1504 ). The black mask layer can be exposed to light through the photo mask ( 1506 ). The black mask layer can be developed to have the desired pattern ( 1508 ). The conductive layer can be etched using the patterned black mask layer as its etching mask ( 1510 ). This eliminates requiring another removable mask for the conductive layer as in the conventional process, thereby simplifying the patterning. Excess portions of the black mask layer can be removed, for example, by ashing ( 1512 ). The black mask layer can be cured to soften and flow over the underlying conductive layer according to a desired profile ( 1514 ). 
     In the example of  FIG. 15   b , a metal layer can be deposited over the black mask layer and the conductive layer ( 1520 ). The metal layer can be coated with a passivation layer ( 1522 ). A removable photo mask can be applied over the passivation layer, where the photo mask can include the desired pattern for the metal layer ( 1524 ). The passivation layer can be exposed to light through the photo mask ( 1526 ). The passivation layer can be developed to have the desired pattern ( 1528 ). The metal layer can be etched using the patterned passivation layer as its etching mask ( 1530 ). This eliminates requiring an additional removable mask for the metal layer as in the conventional process, thereby further simplifying the patterning. Excess portions of the passivation layer can be removed by ashing ( 1532 ). In the case of the bonding area or other conductive traces that should be exposed, all of the passivation layer can be removed from the metal layer. In the case of the conductive bridge or other conductive traces that should be protected, some or none of the passivation layer can be removed from the conductive layer. The remaining portions of the passivation layer can be cured ( 1534 ). 
     It is to be understood that the method is not limited to that described in  FIGS. 15   a - 15   b , but can include other or additional actions for simplified patterning of thin film layers. 
       FIG. 16  illustrates an exemplary mobile telephone  1600  that can include touch sensor panel  1624 , display device  1636 , and other computing system blocks, where the touch sensor panel can have conductive bridges and bonding areas formed by simplified patterning of thin film lines. 
       FIG. 17  illustrates an exemplary digital media player  1700  that can include touch sensor panel  1724 , display device  1736 , and other computing system blocks, where the touch sensor panel can have conductive bridges and bonding areas formed by simplified patterning of thin film lines. 
       FIG. 18  illustrates an exemplary personal computer  1800  that can include touch sensor panel (trackpad)  1824  and display  1836 , and other computing system blocks, where the touch sensor panel can have conductive bridges and bonding areas formed by simplified patterning of thin film lines. 
     The mobile telephone, media player, and personal computer of  FIGS. 16 through 18  can have conductive and passivation layer patterns formed in a simplified manner according to various embodiments, thereby realizing cost, time, and power savings. 
       FIG. 19  illustrates exemplary computing system  1900  that can include one or more of the embodiments of the invention described above. Computing system  1900  can include one or more panel processors  1902  and peripherals  1904 , and panel subsystem  1906 . Peripherals  1904  can include, but are not limited to, random access memory (RAM) or other types of memory or storage, watchdog timers and the like. Panel subsystem  1906  can include, but is not limited to, one or more sense channels  1908 , channel scan logic  1910  and driver logic  1914 . Channel scan logic  1910  can access RAM  1912 , autonomously read data from the sense channels and provide control for the sense channels. In addition, channel scan logic  1910  can control driver logic  1914  to generate stimulation signals  1916  at various frequencies and phases that can be selectively applied to drive lines of touch sensor panel  1924 . In some embodiments, panel subsystem  1906 , panel processor  1902  and peripherals  1904  can be integrated into a single application specific integrated circuit (ASIC). 
     Touch sensor panel  1924  can include a capacitive sensing medium having multiple drive lines and sense lines, although other sensing media can also be used. The drive and sense lines and conductive bridges at the crossings of the drive and sense lines can be formed using simplified patterning according to various embodiments. Each crossing of the drive and sense lines can represent a capacitive sensing node and can be viewed as picture element (pixel)  1926 , which can be particularly useful when touch sensor panel  1924  is viewed as capturing an “image” of touch. (In other words, after panel subsystem  1906  has determined whether a touch event has been detected at each touch sensor in the touch sensor panel, the pattern of touch sensors in the multi-touch panel at which a touch event occurred can be viewed as an “image” of touch (e.g. a pattern of fingers touching the panel).) Each sense line of touch sensor panel  1924  can drive sense channel  1908  (also referred to herein as an event detection and demodulation circuit) in panel subsystem  1906 . 
     Computing system  1900  can also include host processor  1928  for receiving outputs from panel processor  1902  and performing actions based on the outputs that can include, but are not limited to, moving an object such as a cursor or pointer, scrolling or panning, adjusting control settings, opening a file or document, viewing a menu, making a selection, executing instructions, operating a peripheral device coupled to the host device, answering a telephone call, placing a telephone call, terminating a telephone call, changing the volume or audio settings, storing information related to telephone communications such as addresses, frequently dialed numbers, received calls, missed calls, logging onto a computer or a computer network, permitting authorized individuals access to restricted areas of the computer or computer network, loading a user profile associated with a user&#39;s preferred arrangement of the computer desktop, permitting access to web content, launching a particular program, encrypting or decoding a message, and/or the like. Host processor  1928  can also perform additional functions that may not be related to panel processing, and can be coupled to program storage  1932  and display device  1930  such as an LCD panel for providing a UI to a user of the device. Display device  1930  together with touch sensor panel  1924 , when located partially or entirely under the touch sensor panel, can form touch screen  1918 . 
     Note that one or more of the functions described above can be performed by firmware stored in memory (e.g. one of the peripherals  1904  in  FIG. 19 ) and executed by panel processor  1902 , or stored in program storage  1932  and executed by host processor  1928 . The firmware can also be stored and/or transported within any computer-readable storage medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. In the context of this document, a “computer-readable storage medium” can be any medium that can contain or store the program for use by or in connection with the instruction execution system, apparatus, or device. The computer readable storage medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus or device, a portable computer diskette (magnetic), a random access memory (RAM) (magnetic), a read-only memory (ROM) (magnetic), an erasable programmable read-only memory (EPROM) (magnetic), a portable optical disc such a CD, CD-R, CD-RW, DVD, DVD-R, or DVD-RW, or flash memory such as compact flash cards, secured digital cards, USB memory devices, memory sticks, and the like. 
     The firmware can also be propagated within any transport medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. In the context of this document, a “transport medium” can be any medium that can communicate, propagate or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The transport readable medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic or infrared wired or wireless propagation medium. 
       FIG. 20  illustrates an exemplary method for simplified patterning of layers of a thin film that can be used in an electronic device according to various embodiments. In the example of  FIG. 20 , a conductive layer can be deposited on a surface ( 2000 ). The conductive layer can be coated with a photosensitive layer, e.g., a passivation layer ( 2002 ). The photosensitive layer can be developed into a desired pattern of the conductive layer ( 2004 ). The patterned photosensitive layer can be used as an etching mask for the conductive layer ( 2006 ). This can eliminate requiring a separate removable etching mask for the conductive layer. The conductive layer can be etched into the desired pattern based on the photosensitive layer ( 2008 ). 
     In some embodiments, excess portions of the photosensitive layer can be removed after the conductive layer is etched. In some embodiments, the photosensitive layer and the conductive layer can be patterned either together or in succession. 
     Although the invention has been fully described in connection with embodiments thereof 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 the invention as defined by the appended claims.

Metadata:
Filing Date: 20091125
Publication Date: 20130702
Grant Date: 20130702
Priority Date: 20090819
Inventors: KANG SUNGGU
HUANG LILI
HOTELLING STEVEN PORTER
ZHONG JOHN Z.
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F3/0446", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0445", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0445", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0446", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 43604911