PATENT DOCUMENT

Publication Number: US-8153016-B2
Application Number: US-3005208-A
Country: US
Kind Code: B2

Title: Shaping a cover glass

Abstract:
The fabrication of a touch sensor panel having co-planar single-layer touch sensors fabricated on the back side of a cover glass is disclosed. It can be desirable from a manufacturing perspective to perform all thin-film processing steps on a motherglass before separating it into separate parts. To perform thin-film processing on a motherglass before separation, a removable sacrificial layer such as a photoresist can be applied over the thin-film layers. Next, the motherglass can be scribed and separated, and grinding and polishing steps can be performed prior to removing the sacrificial layer. In alternative embodiments, after the protective sacrificial layer is applied, the bulk of the coverglass can be dry-etched using a very aggressive anisotropic etching that etches primarily in the z-direction. In this embodiment, the etching can be patterned using photolithography to create rounded corners or any other shape. The photoresist can then be removed.

Claims:
What is claimed is: 
     
       1. A method of fabricating a plurality of touch sensor panels on one side of a substrate, comprising:
 etching partially through a substrate sheet on a first side of first and second opposing sides of the substrate sheet; 
 forming the plurality of touch sensor panels on the second side of the substrate sheet; 
 applying a removable protective sacrificial layer over the touch sensor panels; 
 singulating the substrate sheet to separate the plurality of touch sensor panels; and 
 removing the protective sacrificial layer from each of the plurality of touch sensor panels. 
 
     
     
       2. The method of  claim 1 , further comprising forming each touch sensor panel as a plurality of co-planar single-layer touch sensors. 
     
     
       3. The method of  claim 1 , further comprising forming the plurality of touch sensor panels using thin-film processing. 
     
     
       4. The method of  claim 1 , wherein the substrate is a cover glass and the substrate sheet is a mother glass. 
     
     
       5. The method of  claim 1 , further comprising applying photoresist as the removable protective sacrificial layer. 
     
     
       6. The method of  claim 1 , further comprising singulating the substrate sheet using scribe and break techniques. 
     
     
       7. The method of  claim 1 , further comprising performing grinding and polishing the separated touch sensor panels prior to removing the sacrificial layer. 
     
     
       8. The method of  claim 1 , further comprising singulating the substrate sheet using dry-etching techniques. 
     
     
       9. The method of  claim 1 , further comprising forming a step in the substrate supporting each of the touch sensor panels prior to singulating the substrate sheet. 
     
     
       10. The method of  claim 9 , further comprising forming the step using etching techniques. 
     
     
       11. The method of  claim 1 , further comprising forming radiused corners in the substrate supporting each of the touch sensor panels prior to forming the touch sensor panels. 
     
     
       12. The method of  claim 11 , further comprising forming the radiused corners using etching techniques.

Description:
FIELD OF THE INVENTION 
     This relates generally to input devices for computing systems, and more particularly, to the fabrication of a touch sensor panel on the back side of a cover glass. 
     BACKGROUND OF THE INVENTION 
     Many types of input devices are presently available for performing operations in a computing system, such as buttons or keys, mice, trackballs, touch sensor panels, joysticks, touch screens and the like. Touch screens, in particular, are becoming increasingly 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. The touch sensor panel can be positioned in front of a display screen so that the touch-sensitive surface covers the viewable area of the display screen. Touch screens can allow a user to make selections and move a cursor by simply touching the display screen via a finger or stylus. In general, the touch screen can recognize the touch and position of the touch on the display screen, and the computing system can interpret the touch and thereafter perform an action based on the touch event. 
     Touch sensor panels can be implemented as an array of pixels formed by multiple drive lines (e.g. rows) crossing over multiple sense lines (e.g. columns), where the drive and sense lines are separated by a dielectric material. An example of such a touch sensor panel is described in Applicant&#39;s co-pending U.S. application Ser. No. 11/650,049 entitled “Double-Sided Touch Sensitive Panel and Flex Circuit Bonding,”filed on Jan. 3, 2007, the contents of which are incorporated by reference herein. However, touch sensor panels having drive and sense lines formed on the bottom and top sides of a single substrate can be expensive to manufacture. One reason for this additional expense is that thin-film processing steps must be performed on both sides of the glass substrate, which requires protective measures for the processed side while the other side is being processed. Another reason is the cost of the flex circuit fabrication and bonding needed to connect to both sides of the substrate. 
     SUMMARY OF THE INVENTION 
     This relates to the fabrication of a touch sensor panel having touch sensors fabricated on a substrate for detecting touch events (the touching of one or multiple fingers or other objects upon a touch-sensitive surface at distinct locations at about the same time). When forming a touch sensor panel on a substrate, if the substrate is singulated before processing, the separation step is relatively easy to accomplish with laser or wheel scribing and breaking, followed by optional grinding and polishing to achieve a cosmetically pleasing shape and touch. Because separation is performed before processing, protection of sensitive circuitry during grinding and polishing is not needed. However, it can be desirable from a manufacturing perspective to perform all processing steps on a substrate sheet before separating it into separate parts with rounded corners (in the case of no bezel). 
     To perform processing on a substrate sheet before separation, a removable sacrificial layer such as a photoresist can be applied over the sensitive circuitry. Next, the parts can be scribed and separated to get individual parts, and grinding and polishing steps can be performed prior to removing the sacrificial layer. In alternative embodiments, after the protective sacrificial layer is applied, the bulk of the substrate sheet can be dry-etched using a very aggressive anisotropic etching that etches primarily in the z-direction. This process is similar to reactive ion etching, in which photoresist is applied to the areas to be preserved, and the unwanted areas are then etched away. In this embodiment, the etching can be patterned using photolithography to create rounded corners or any other shape. The photoresist can then be removed. 
     In further alternative embodiments, dry etching can be utilized on a blank substrate sheet to etch partially through the sheet to form the radiused corners or other shapes. The substrate sheet can then be subjected to processing to apply various layers of the touch sensor panel, followed by laser scribing and breaking to singulate the parts. This process avoids the need to submit the sensitive layers to the bulk shaping etch process, which might damage them. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1   a  illustrates a partial top view of an exemplary substantially transparent touch sensor panel having co-planar single-layer touch sensors fabricated on a single side of a substrate according to one embodiment of this invention. 
         FIG. 1   b  illustrates a partial top view of an exemplary substantially transparent touch sensor panel including metal traces running in the border areas of the touch sensor panel according to one embodiment of this invention. 
         FIG. 1   c  illustrates an exemplary connection of columns and row patches to metal traces in the border area of the touch sensor panel according to one embodiment of this invention. 
         FIG. 2   a  illustrates an exemplary cross-section of a touch sensor panel showing single-layer Indium Tin Oxide (SITO) traces and metal traces connected though a via in a dielectric material according to one embodiment of this invention. 
         FIG. 2   b  is a close-up view of the exemplary cross-section shown in  FIG. 2   a  according to one embodiment of this invention. 
         FIG. 3  illustrates an exemplary stackup of SITO on a touch sensor panel substrate bonded to a cover glass according to one embodiment of this invention. 
         FIG. 4   a  illustrates an exemplary stackup of SITO formed on the back of a cover glass according to one embodiment of this invention. 
         FIG. 4   b  illustrates another exemplary stackup of SITO formed on the back of a cover glass according to one embodiment of this invention. 
         FIG. 5   a  illustrates an exemplary stackup of SITO formed on the back of a cover glass and bonded to an overlapping bezel according to one embodiment of this invention. 
         FIG. 5   b  illustrates an exemplary stackup of SITO formed on the back of a stepped cover glass and bonded to an overlapping bezel according to one embodiment of this invention. 
         FIGS. 6   a  and  6   b  illustrate exemplary processing for combining dry-etch shaping with thin film deposition on the cover glass according to one embodiment of this invention. 
         FIG. 7  illustrates an exemplary computing system operable with a touch sensor panel according to one embodiment of this invention. 
         FIG. 8   a  illustrates an exemplary mobile telephone that can include a touch sensor panel and computing system according to one embodiment of this invention. 
         FIG. 8   b  illustrates an exemplary digital audio/video player that can include a touch sensor panel and computing system according to one embodiment of this invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the following description of preferred 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 in which the invention can be practiced. It is to be understood that other embodiments can be used and structural changes can be made without departing from the scope of the embodiments of this invention. 
     This relates to the fabrication of a touch sensor panel with touch sensors formed on a substrate. It can be desirable from a manufacturing perspective to perform all touch sensor processing steps on a single substrate sheet before separating it into separate parts with rounded corners (in the case of no bezel). To perform touch sensor processing on the substrate sheet before separation, a removable sacrificial layer such as a photoresist can be applied over the thin-film layers. Next, the parts can be scribed and separated to get individual parts, and grinding and polishing steps can be performed prior to removing the sacrificial layer. In alternative embodiments, after the protective sacrificial layer is applied, the bulk of the substrate can be dry-etched using a very aggressive anisotropic etching that etches primarily in the z-direction. In this embodiment, the etching can be patterned using photolithography to create rounded corners or any other shape. The photoresist can then be removed. 
     Although some embodiments of this invention may be described herein in terms of mutual capacitance multi-touch sensor panels, it should be understood that embodiments of this invention are not so limited, but can be additionally applicable to self-capacitance sensor panels and single-touch sensor panels. Furthermore, although the touch sensors in the sensor panel may be described herein in terms of an orthogonal array of touch sensors having rows and columns, embodiments of this invention are not limited to orthogonal arrays, but can be generally applicable to touch sensors arranged in any number of dimensions and orientations, including diagonal, concentric circle, three-dimensional and random orientations. 
     Additionally, although some embodiments of the invention may be described herein in terms of substantially transparent touch sensor panels, in other embodiments the touch sensor panel can be opaque. Although the touch sensors may be described herein as being formed as a co-planar single-layer on a substrate, in other embodiments, the touch sensors can be formed from non-coplanar layers on a single substrate. In some embodiments, the substrate is described as being the back side of a cover glass, with the original single substrate sheet being referred to as a motherglass, but it should be understood that embodiments of the invention are generally applicable to other substrates as well. In some embodiments, the touch sensors are formed using thin-film processing techniques, but other processing techniques can also be used. 
       FIG. 1   a  illustrates a partial view of exemplary substantially transparent touch sensor panel  100  having co-planar single-layer touch sensors fabricated on a single side of a substrate according to embodiments of the invention. In the example of  FIG. 1   a , touch sensor panel  100  having eight columns (labeled a through h) and six rows (labeled 1 through 6) is shown, although it should be understood that any number of columns and rows can be employed. Columns a through h can generally be columnar in shape, although in the example of  FIG. 1   a , one side of each column includes staggered edges and notches designed to create separate sections in each column. Each of rows  1  through  6  can be formed from a plurality of distinct patches or pads, each patch including a trace of the same material as the patch and routed to the border area of touch sensor panel  100  for enabling all patches in a particular row to be connected together through metal traces (not shown in  FIG. 1   a ) running in the border areas. These metal traces can be routed to a small area on one side of touch sensor panel  100  and connected to a flex circuit  102 . As shown in the example of  FIG. 1   a , the patches forming the rows can be arranged in a generally pyramid-shaped configuration. In  FIG. 1   a , for example, the patches for rows  1 - 3  between columns a and b are arranged in an inverted pyramid configuration, while the patches for rows  4 - 6  between columns a and b are arranged in an upright pyramid configuration. 
     The columns and patches of  FIG. 1   a  can be formed in a co-planar single layer of conductive material. In touch screen embodiments, the conductive material can be a substantially transparent material such as Single-layer Indium Tin Oxide (SITO), although other materials can also be used. The SITO layer can be formed either on the back of a cover glass or on the top of a separate substrate. Although SITO may be referred to herein for purposes of simplifying the disclosure, it should be understood that other conductive materials can also be used according to embodiments of the invention. 
       FIG. 1   b  illustrates a partial view of exemplary substantially transparent touch sensor panel  100  including metal traces  104  and  106  running in the border areas of the touch sensor panel according to embodiments of the invention. Note that the border areas in  FIG. 1   b  are enlarged for clarity. Each column a-h can include SITO trace  108  that allows the column to be connected to a metal trace through a via (not shown in  FIG. 1   b ). One side of each column includes staggered edges  114  and notches  116  designed to create separate sections in each column. Each row patch  1 - 6  can include SITO trace  110  that allows the patch to be connected to a metal trace through a via (not shown in  FIG. 1   b ). SITO traces  110  can allow each patch in a particular row to be self-connected to each other. Because all metal traces  104  and  106  are formed on the same layer, they can all be routed to the same flex circuit  102 . 
     If touch sensor panel  100  is operated as a mutual capacitance touch sensor panel, either the columns a-h or the rows  1 - 6  can be driven with one or more stimulation signals, and fringing electric field lines can form between adjacent column areas and row patches. In  FIG. 1   b , it should be understood that although only electric field lines  112  between column a and row patch  1  (a- 1 ) are shown for purposes of illustration, electric field lines can be formed between other adjacent column and row patches (e.g. a- 2 , b- 4 , g- 5 , etc.) depending on what columns or rows are being stimulated. Thus, it should be understood that each column-row patch pair (e.g. a- 1 , a- 2 , b- 4 , g- 5 , etc.) can represent a two-electrode pixel or sensor at which charge can be coupled onto the sense electrode from the drive electrode. When a finger touches down over one of these pixels, some of the fringing electric field lines that extend beyond the cover of the touch sensor panel are blocked by the finger, reducing the amount of charge coupled onto the sense electrode. This reduction in the amount of coupled charge can be detected as part of determining a resultant “image” of touch. It should be noted that in mutual capacitance touch sensor panel designs as shown in  FIG. 1   b , no separate reference ground is needed, so no second layer on the back side of the substrate, or on a separate substrate, is needed. 
     However, touch sensor panel  100  can also be operated as a self-capacitance touch sensor panel. In such an embodiment, a reference ground plane can be formed on the back side of the substrate or on a separate substrate. In a self-capacitance touch sensor panel, each pixel or sensor has a self-capacitance to the reference ground that can be changed due to the presence of a finger. In self-capacitance embodiments, the self-capacitance of columns a-h can be sensed independently, and the self-capacitance of rows  1 - 6  can also be sensed independently. 
       FIG. 1   c  illustrates an exemplary connection of columns and row patches to the metal traces in the border area of the touch sensor panel according to embodiments of the invention.  FIG. 1   c  represents “Detail A” as shown in  FIG. 1   b , and shows column “a”and row patches  4 - 6  connected to metal traces  118  through SITO traces  108  and  110 . Because SITO traces  108  and  110  are separated from metal traces  118  by a dielectric material, vias  120  formed in the dielectric material allow the SITO traces to connect to the metal traces. 
       FIG. 2   a  illustrates an exemplary cross-section of touch sensor panel  200  showing SITO trace  208  and metal traces  218  connected though via  220  in dielectric material  222  according to embodiments of the invention.  FIG. 2   a  represents view B-B as shown in  FIG. 1   c.    
       FIG. 2   b  is a close-up view of the exemplary cross-section shown in  FIG. 2   a  according to embodiments of the invention.  FIG. 2   b  shows one exemplary embodiment wherein SITO trace  208  has a resistivity of about 155 ohms per square max. In one embodiment, dielectric  222  can be about 1500 angstroms of inorganic SiO 2 , which can be processed at a higher temperature and therefore allows the SITO layer to be sputtered with higher quality. In another embodiment, dielectric  222  can be about 3.0 microns of organic polymer. The 1500 angstroms of inorganic SiO 2  can be used for touch sensor panels small enough such that the crossover capacitance (between SITO trace  208  and metal traces  218 ) is not an issue. 
     For larger touch sensor panels (having a diagonal dimension of about 3 inches or greater), crossover capacitance can be an issue, creating an error signal that can only partially be compensated. Thus, for larger touch sensor panels, a thicker dielectric layer  222  with a lower dielectric constant such as about 3.0 microns of organic polymer can be used to lower the crossover capacitance. However, use of a thicker dielectric layer can force the SITO layer to be sputtered at a lower temperature, resulting in lower optical quality and higher resistivity. 
     Referring again to the example of  FIG. 1   c , column edges  114  and row patches  4 - 6  can be staggered in the x-dimension because space must be made for SITO traces  110  connecting row patches  4  and  5 . (It should be understood that row patch  4  in the example of  FIG. 1   c  is really two patches stuck together.) To gain optimal touch sensitivity, it can be desirable to balance the area of the electrodes in pixels a- 6 , a- 5  and a- 4 . However, if column “a” was kept linear, row patch  6  can be slimmer than row patch  5  or  6 , and an imbalance would be created between the electrodes of pixel a- 6 . 
       FIG. 3  illustrates an exemplary stackup of SITO on a touch sensor panel substrate bonded to a cover glass according to embodiments of the invention. The stackup can include touch sensor panel substrate  300 , which can be formed from glass, upon which anti-reflective (AR) film  310  can be formed on one side and metal  302  can be deposited and patterned on the other side to form the bus lines in the border areas. Metal  302  can have a resistivity of 0.8 ohms per square maximum. Insulating layer  304  can then be deposited over substrate  300  and metal  302 . Insulating layer can be, for example, SiO 2  with a thickness of 1500 angstroms, or 3 microns of organic polymer. Photolithography can be used to form vias  306  in insulator  304 , and conductive material  308  can then deposited and patterned on top of the insulator and metal  302 . The single layer of conductive material  308 , which can be formed from transparent conductive material such as ITO having a resistivity of 155 ohms per square maximum, can be more transparent than multi-layer designs, and can be easier to manufacture. Flex circuit  312  can be bonded to conductive material  303  and metal  302  using adhesive  314  such as anisotropic conductive film (ACF). The entire subassembly can then be bonded to cover glass  316  and black mask  320  using adhesive  318  such as pressure sensitive adhesive (PSA). 
       FIG. 4   a  illustrates an exemplary stackup of SITO formed on the back of a cover glass according to embodiments of the invention. The stackup can include cover material  416 , which can be formed from glass. Black mask  420  of a material such as 2 microns of organic polymer can be formed on the back side of cover material  416 . An optional planarization layer  422  can be formed over cover material  416  and black mask  420  to prepare the surface for subsequent thin-film deposition of metal  402  and insulating layer  404 . Metal  402  can be deposited and patterned over optional planarization layer  422  or directly over black mask  420  and/or cover material  416  to form the bus lines in the border areas. Metal  402  can have a resistivity of 0.8 ohms per square maximum. Insulating layer  404  can then be deposited over metal  402  and optional planarization layer  422 . Insulating layer can be, for example, SiO 2  with a thickness of 1500 angstroms, or 3 microns of organic polymer. Photolithography can be used to form vias  406  in insulator  404 , and conductive material  408  can then deposited and patterned on top of the insulator and metal  402 . The single layer of conductive material  408 , which can be formed from transparent conductive material such as ITO having a resistivity of 155 ohms per square maximum, can be more transparent than multi-layer designs, and can be easier to manufacture. Flex circuit  412  can be bonded to conductive material  408  and metal  402  using adhesive  414  such as anisotropic conductive film (ACF). Anti-reflective (AR) film  410  can also be formed over conductive material  408 . 
       FIG. 4   b  illustrates another exemplary stackup of SITO formed on the back of a cover glass according to embodiments of the invention.  FIG. 4   b  is similar to  FIG. 4   a , except that inorganic black mask  424  is used instead of organic black mask. Inorganic black mask  424  can be formed from multiple layers of silicon and silicon oxide, or about 500 angstroms of chrome oxide, for example. Inorganic black mask  424  must be a good insulator (greater than 10 MOhms per square) to avoid shorting the metal lines. Inorganic black mask  424  is thinner than organic black mask and helps prevent reflections but is not as good as organic black mask for blocking light. Therefore, the example of  FIG. 4   b , additional dummy metal  426  can be deposited in addition to metal traces  402  to further block light from passing through. 
     The forming of a touch sensor panel on the back side of a cover glass can also be applicable to touch sensor panel designs other than the co-planar single layer design disclosed herein. For example, Applicant&#39;s co-pending U.S. patent application Ser. No. 11/818,498 entitled “Touch-Sensitive Display” and filed on Jun. 13, 2007, the contents of which are incorporated by reference herein, discloses a touch sensor panel formed from non-co-planar diamond-shaped rows and columns formed on the same side of a substrate. As with  FIGS. 4   a  and  4   b  herein, the non-co-planar diamond-shaped rows and columns formed on the same side of a substrate can also be formed on the back side of a cover glass. 
       FIG. 5   a  illustrates an exemplary stackup of SITO formed on the back of a cover glass and bonded to an overlapping bezel according to embodiments of the invention. The stackup in  FIG. 5   a  is similar to what is shown in  FIGS. 4   a  and  4   b , except that no black mask or planarization layer is formed on the back of cover glass  516 . In  FIG. 5   a , cover glass  516  can be bonded under an overhanging bezel  528  using adhesive  530 , which eliminates the need for black mask and extra metal for blocking purposes, and simplifies the manufacturing steps. However, this design increases the thickness in the z-dimension. 
       FIG. 5   b  illustrates an exemplary stackup of SITO formed on the back of a stepped cover glass and bonded to an overlapping bezel according to embodiments of the invention. The embodiment of  FIG. 5   b  reduces the thickness in the z-dimension by creating step  532  in cover glass  516 . Step  532  can make cover glass  516  and product bezel  528  substantially coplanar using a lap joint. 
     The formation of a step in the coverglass can be performed for multiple touch sensor panels while the cover glass is still in a single large sheet, the single sheet referred to herein as a motherglass. First, etching can be used to create the steps in the motherglass for multiple parts. Next, individual touch sensor panel cover glass parts can be singulated using traditional scribe and break processes, or using a further etching step. 
     When forming a touch sensor panel on the back of a cover glass, if the cover glass is singulated before thin-film processing, the separation step is relatively easy to accomplish with laser or wheel scribing and breaking, followed by optional grinding and polishing to achieve a cosmetically pleasing shape and touch. Because separation is performed before thin-film processing, protection of the thin-films during grinding and polishing is not needed. However, it can be desirable from a manufacturing perspective to perform all thin-film processing steps on a motherglass before separating it into separate parts with rounded corners (in the case of no bezel). To perform thin-film processing on a motherglass before separation, a removable sacrificial layer such as a photoresist is applied over the thin-film layers. Next, the parts can be scribed and separated to get individual parts, and grinding and polishing steps can be performed prior to removing the sacrificial layer. In alternative embodiments, after the protective sacrificial layer is applied, the bulk of the coverglass can be dry-etched using a very aggressive anisotropic etching that etches primarily in the z-direction. This process is similar to reactive ion etching, in which photoresist is applied to the areas to be preserved, and the unwanted areas are then etched away. In this embodiment, the etching can be patterned using photolithography to create rounded corners or any other shape. The photoresist can then be removed. 
     In further alternative embodiments, dry etching can be utilized on a blank motherglass to etch partially through the motherglass to form the radiused corners or other shapes. The motherglass can then be subjected to thin film processing, followed by laser scribing and breaking to singulate the parts. This process avoids needing to submit the thin films to the bulk shaping etch process, which might damage them. 
       FIGS. 6   a  and  6   b  illustrate exemplary processing for combining dry-etch shaping with thin film deposition on the cover glass according to embodiments of the invention. In  FIG. 6   a , the front cosmetic surface  600  is dry-etched partially through the front side of the motherglass to form the cosmetic corners  602  and step  604  in the glass. The motherglass will then go to thin film processing at  606  and finally laser-scribed and broken to panel size  608 . This method produces sharp corner  610  on the bottom ledge that can be removed. 
       FIG. 6   b  illustrates the reverse process. Thin films  606  are deposited on motherglass  612 . The motherglass can then be sent through for dry-etching to size (see reference character  614 ). The dry etching process should not damage the thin films. Using this process, bottom corner  602  can be shaped and holes can be added the glass. The process chosen will be dependent on individual product requirements. 
       FIG. 7  illustrates exemplary computing system  700  operable with the touch sensor panel described above according to embodiments of this invention. Touchscreen  742 , which can include touch sensor panel  724  and display device  740  (e.g. an LCD module), can be connected to other components in computing system  700  through connectors integrally formed on the sensor panel, or using flex circuits. Computing system  700  can include one or more panel processors  702  and peripherals  704 , and panel subsystem  706 . The one or more processors  702  can include, for example, ARM968 processors or other processors with similar functionality and capabilities. However, in other embodiments, the panel processor functionality can be implemented instead by dedicated logic such as a state machine. Peripherals  704  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  706  can include, but is not limited to, one or more analog channels  708 , channel scan logic  710  and driver logic  714 . Channel scan logic  710  can access RAM  712 , autonomously read data from the analog channels and provide control for the analog channels. This control can include multiplexing or otherwise connecting the sense lines of touch sensor panel  724  to analog channels  708 . In addition, channel scan logic  710  can control the driver logic and stimulation signals being selectively applied to the drive lines of touch sensor panel  724 . In some embodiments, panel subsystem  706 , panel processor  702  and peripherals  704  can be integrated into a single application specific integrated circuit (ASIC). 
     Driver logic  714  can provide multiple panel subsystem outputs  716  and can present a proprietary interface that drives high voltage driver  718 . High voltage driver  718  can provide level shifting from a low voltage level (e.g. complementary metal oxide semiconductor (CMOS) levels) to a higher voltage level, providing a better signal-to-noise (S/N) ratio for noise reduction purposes. Panel subsystem outputs  716  can be sent to decoder  720  and level shifter/driver  738 , which can selectively connect one or more high voltage driver outputs to one or more panel row or drive line inputs  722  through a proprietary interface and enable the use of fewer high voltage driver circuits in the high voltage driver  718 . Each panel row input  722  can drive one or more drive lines in touch sensor panel  724 . In some embodiments, high voltage driver  718  and decoder  720  can be integrated into a single ASIC. However, in other embodiments high voltage driver  718  and decoder  720  can be integrated into driver logic  714 , and in still other embodiments high voltage driver  718  and decoder  720  can be eliminated entirely. 
     Computing system  700  can also include host processor  728  for receiving outputs from panel processor  702  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 connected 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  728  can also perform additional functions that may not be related to panel processing, and can be coupled to program storage  732  and display device  740  such as an LCD for providing a user interface (UI) to a user of the device. 
     The touch sensor panel described above can be advantageously used in the system of  FIG. 7  to provide a space-efficient touch sensor panel and UI that is lower cost, more manufacturable, and fits into existing mechanical control outlines (the same physical envelope). 
       FIG. 8   a  illustrates exemplary mobile telephone  836  that can include touch sensor panel  824  and display device  830  stackups (optionally bonded together using PSA  834 ) and computing system described above according to embodiments of the invention.  FIG. 8   b  illustrates exemplary digital audio/video player  840  that can include touch sensor panel  824  and display device  830  stackups (optionally bonded together using PSA  834 ) and computing system described above according to embodiments of the invention. The mobile telephone and digital audio/video player of  FIGS. 8   a  and  8   b  can advantageously benefit from the touch sensor panel described above because the touch sensor panel can enable these devices to be smaller and less expensive, which are important consumer factors that can have a significant effect on consumer desirability and commercial success. 
     Although embodiments of this invention 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 embodiments of this invention as defined by the appended claims.

Metadata:
Filing Date: 20080212
Publication Date: 20120410
Grant Date: 20120410
Priority Date: 20071003
Inventors: HOTELLING STEVE PORTER
ZHONG JOHN Z.
CLAYTON JOSEPH EDWARD
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F3/0443", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0448", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0448", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0443", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 40522371