Patent Publication Number: US-2007094873-A1

Title: System for making a conductive circuit on a substantially non-conductive substrate

Description:
This application is a Divisional of U.S. application Ser. No. 10/612,705 filed Jun. 30, 2003, which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION  
      The present invention is related to printed circuit boards. More specifically, the present invention relates to a method and apparatus method and apparatus for forming printed circuit boards using imprinting and grinding.  
     BACKGROUND OF THE INVENTION  
      A printed circuit board (“PCB”) is a multi-layer plastic board that includes printed circuits on one or more layers of insulative material. A printed circuit is a pattern of conductors that corresponds to the wiring of an electronic circuit formed on one or more layers of insulative material. The printed circuit board includes electrical traces that are routed on the various layers of the PCB. PCBs also include vias which are solid electrical paths connecting one layer to another layer. A via can be used to connect a trace on one layer of a PCB to another trace on another layer of the PCB. A PCB also includes other layers of metallization for ground planes, power planes or reference voltage planes.  
      One conventional way to make a PCB is to start with a sheet or strip of dielectric coated with a conductive metal such as copper. Using various drilling, plating, lithographic and metal etching steps a pattern is then formed leaving metal where traces are desired. The traces are on top of the sheet or strip of dielectric. One sheet forms one layer of the PCB.  
      Another conventional way to make a PCB is to start with a sheet or strip of non-conductive plastic or ceramic, deposit ink in a pattern that forms the conductive traces, sinter the ink to form metal traces. The sheet or strip of non-conductive plastic or ceramic is sometimes referred to as a manufacturing panel. Fiducial markings or coupons are placed on the manufacturing panels. A PCB can have several layers of traces. Five or six layers is common for a multi-layer PCB. Each layer is formed on a manufacturing panel and then the various layers are registered with the fiducial markings or coupons and bonded together. The manufacturing panels form a laminate that includes a number of individual PCBs. The laminate formed is then further processed. Vias or paths from one layer to another layer within the PCB are formed by drilling through the PCB to hit various pads on each of the layers. The pads are generally large enough to account for any inaccuracies associated with routing design or misregistration between the layers of the PCB. A PCB may also include various planes for power, ground reference or another voltage reference. As a result, each PCB requires substantial routing of signal lines and power-supply capability. Design changes are difficult to make. Accounting for inaccuracies, such as making large inner pads for a via, limits the density of the signal carrying lines and makes routing more difficult. Furthermore, the resulting PCB typically has stub traces that may result in undesirable electrical qualities. For example, such stubs vary the impedence and may result in crosstalk between signal lines. Another aspect of current PCBs is that each plate carries a single layer of traces. Once the further processing of laminate formed is complete, the manufacturing panel is cut or singulated to form individual printed circuit boards. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The invention is pointed out with particularity in the appended claims. However, a more complete understanding of the present invention may be derived by referring to the detailed description when considered in connection with the figures, wherein like reference numbers refer to similar items throughout the figures and:  
       FIG. 1  is a top view of a printed circuit board, according to an embodiment of the invention.  
       FIG. 2  is a side view of a panel of material passing through a roller mechanism to indent the panel of the material, according to an embodiment of this invention.  
       FIG. 3  is a side view of a panel of material after plating one of the major surfaces of an indented panel with a conductive material, according to an embodiment of this invention.  
       FIG. 4  is a side view of a panel of material after plating two of the major surfaces of an indented panel with a conductive material, according to an embodiment of this invention.  
       FIG. 5  is a side view of a grinder mechanism removing at least a portion of the plated material from one surface of the panel, according to an embodiment of this invention.  
       FIG. 6  is a perspective view of a roller carrying a plate, according to an embodiment of this invention.  
       FIG. 7  is a front view of a roller that indents a panel of material and a load roller, according to an embodiment of this invention.  
       FIG. 8  is a cross-sectional side view of a portion of a panel of material after the panel of material has been indented, according to an embodiment of this invention.  
       FIG. 9  is a cross-sectional side view of a portion of an indented panel of material after the panel of material has been plated, according to an embodiment of this invention.  
       FIG. 10  is a cross-sectional side view of a portion of an indented panel of material after a portion of the plated material has been removed, according to an embodiment of this invention.  
       FIG. 11  is a cross-sectional side view of several panels joined to form a multi-layer electrical device, according to an embodiment of this invention.  
       FIG. 12  is a flow diagram showing a method of forming a conductive circuit on a non-conductive substrate or panel, according to an embodiment of this invention.  
       FIG. 13  is a flow diagram showing another method of forming a conductive circuit on a non-conductive substrate or panel, according to an embodiment of this invention.  
       FIG. 14  is a top view of a panel and an indenting system including a set of rollers for forming indented features on the panel, according to an embodiment of this invention.  
       FIG. 15  is a front view of an indenting system including a first set of rollers and a second set of rollers for forming indented features on grooves on two sides of a panel, according to an embodiment of this invention.  
       FIG. 16  is a side view of a panel of material passing through a set of rollers to indent one side of the material, according to an embodiment of this invention.  
       FIG. 17  is a side view of a grinder mechanism for removing at least a portion of the plated material from two major surfaces of the panel substantially simultaneously, according to an embodiment of this invention.  
       FIG. 18  is a side view of a grinder mechanism for removing at least a portion of the plated material from two major surfaces of the panel substantially simultaneously, according to an embodiment of this invention.  
       FIG. 19  is a schematic view of a system for forming printed circuit boards, according to an embodiment of this invention.  
       FIG. 20  is a top view of a wafer, according to an embodiment of this invention.  
       FIG. 21  is a top view of a die within a package, according to an embodiment of this invention.  
      The description set out herein illustrates the various embodiments of the invention and such description is not intended to be construed as limiting in any manner. 
    
    
     DETAILED DESCRIPTION  
      In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings that form a part hereof, and in which are shown by way of illustrating specific embodiments in which the invention can be practiced. The embodiments illustrated are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed herein. Other embodiments can be utilized and derived therefrom, such that structural and logical substitutions and changes can be made without departing from the scope of present inventions. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of various embodiments of the invention is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled.  
       FIG. 1  is a top view of a printed circuit board  100 , according to an embodiment of the invention. The printed circuit board (“PCB”)  100  is a multi-layer plastic board that includes patterns of printed circuits on one or more layers of insulated material. The patterns of conductors correspond to wiring of an electronic circuit formed on one or more of the layers of the printed circuit board  100 . The printed circuit board  100  also includes electrical traces  110 . The electrical traces  110  can be found on an exterior surface  120  of a printed circuit board  100  and also can be found on the various layers within the printed circuit board  100 . Printed circuit boards also include through holes (not shown in  FIG. 1  but shown in  FIGS. 10- 11 ) which are used to interconnect traces on various layers of the printed circuit board  100 . The printed circuit board can also include planes of metallized materials such as ground planes, power planes, or voltage reference planes (not shown in  FIG. 1 ). Through holes can also be used to interconnect like planes in the printed circuit board  100 . A through hole can either be a plated through hole which is essentially a hollow conductor formed within the printed circuit board  100  for interconnecting conductors or layers of a printed circuit board, or it can be a via which is a solid conductor used to interconnect layers of the printed circuit board  100 .  
      The printed circuit board  100  is also populated with various components  130 ,  132 ,  134 ,  136 ,  138 . The components  130 ,  132 ,  134 ,  136 ,  138  can either be discreet components or semiconductor chips which include thousands of transistors. The components  130 ,  132 ,  134 ,  136 ,  138  can use any number of technologies to connect to the exterior surface  120  of the circuit board or to the printed circuit board  100 . For example, pins may be inserted into plated through holes or pins may be extended through the printed circuit board  100 . An alternative technology is surface mount technology where an electrical component, such as component  136 , mounts to an array of pads on the exterior surface  120  of the printed circuit board  100 . For example, component  136  could be a ball grid array package or device that has an array of balls or bumps that interact or are connected to a corresponding array of pads on the exterior surface  120  of the printed circuit board  100 . The printed circuit board  100  can also include connectors for making external connections to other electrical or electronic devices.  
      As shown in  FIG. 1 , the printed circuit board  100  includes a first edge connector  140  and a second edge connector  142 . As shown in  FIG. 1  there are external traces, such as electrical trace  110 , on the external surface  120  of the printed circuit board  100  that connect to certain of the outputs associated with the first edge connector  140 . Other traces that connect with the edge connectors  140 ,  142  will have traces internal to the printed circuit board  100 .  
      Many of the electrical components which are used to populate the printed circuit board  100  are expensive. For example, a central processing chip, that may cost hundreds or thousands of dollars, is generally mounted on a printed circuit board  100 . As a result, it is desirable to test the integrity of printed circuit boards, such as printed circuit board  100 , before electrical components, such as electrical components  130 ,  132 ,  134 ,  136 ,  138 , are mounted onto the printed circuit board  100 . It should be noted that printed circuit boards are also called boards or circuit boards. Once populated many of the printed circuit boards are called cards or adapters. Printed circuit boards are prevalent and are used in computers and other devices. For example, printed circuit boards are used in computers and are referred to as motherboards, expansion boards, daughter cards, controller cards, network interface cards, or video adapters or video graphics adapters. It should be noted that these are just a small sample of the many different types of electronic devices that are based upon a printed circuit board, such as the one shown in  FIG. 1 .  
       FIG. 2  is a side view of a panel  210  of material passing through a roller mechanism  220  to indent the panel  210  of the material, according to an embodiment of this invention. The roller mechanism includes a first indenting roller  221  and a second indenting roller  222 . The roller mechanism  220  also includes load rollers  224 ,  225 ,  226 ,  227 . The load rollers  224 ,  225 ,  226 ,  227  apply opposing loads, depicted by arrows  234 ,  235 ,  236 ,  237 , on the panel  210  to flatten the panel  210  in and around the area of the roller mechanism  220 . For example, load roller  224  opposes or is positioned directly, or nearly directly, opposite from load roller  225 . The force produced by load roller  224  is load  234  which is directly opposite the load  235  produced by load roller  225 . Similarly, load roller  226  is positioned opposite load roller  227 . Load roller  226  produces load  236  which directly opposes the load  237  produced by the load roller  227 . The various loads  234 ,  235 ,  236 ,  237  as well as loads produced by the first indenting roller  221  and the second indenting roller  222  flatten the panel of material  210  in the area of the roller mechanism  220 . The panel of material  210  is a non-insulated material such as ABF plastic, a thermoplastic, or any other type of thermoset plastic. The panel of material  210 , after processing which will be discussed below, becomes one layer in a printed circuit board. It should be also noted that some circuit boards may have a single layer so another option is that the panel  210  may become a single layer in a printed circuit board. The first indenting roller  221  and the second indenting roller  222  are provided with pattern surfaces  241  and  242 , respectively.  
      As the first indenting roller  221  roles and places a load on a major surface  211  of the panel of material  210 , the pattern surface  241  of the first indenting roller  222  forms indentations within the major surface of the panel  211 . Similarly, as the second indenting roller  222  rolls or places a load on a second major surface  212  of the panel of material  210 , the pattern surface  242  produces indentations and patterns in the second major surface  212  of the panel of material  210 . It should be noted that indentations can produce all sorts of features including openings that pass through the panel of material  210  from the first major surface  211  to the second major surface  212 . In other words, the features on the surface  241  of the first indenting roller  221  and the features on the surface  242  of the second indenting roller  222  can include channels or pathways, paths, and through holes. It should be noted that the first indenting roller  221  and the second indenting roller  222  are indexed with respect to each other so that as the indentations are made in the first major surface  211  and the second major surface  212  of the panel of material  210 , the features will be registered with one another as patterns of traces, through holes and pads are registered from layer to layer within a printed circuit board, such as printed circuit board  100  shown in  FIG. 1 .  
      After the panel of material  210  and specifically the first major surface  211  and the second major surface  212  of the panel have been indented with the features from the surface  241  of the first indenting roller  221  and the features associated with the surface  242  of the second indenting roller  222 , the panel of material  210  is plated with an electrically conductive material.  
       FIG. 3  is a side view of a panel of material  210  after plating one of the major surfaces  211  of the indented panel  210  with a conductive material  311 , according to an embodiment of this invention. Although plating is mentioned as one way of placing conductive material  311  on to the first major surface  211  of the panel of material  210 , there are many other ways to deposit conductive material  311  on to the first major surface  211  of the panel of material  210 . For example, in addition to plating, the panel  210  could be placed in a chamber and conductive material  311  could be sputtered or placed thereon by chemical vapor deposition. It is contemplated that any form of depositing a conductive material  311  on to the surface  211  of the panel of material  210  is within the scope of this invention. Furthermore, the panel of material  210  is not necessarily of a specific size. In fact, the panel of material  210  could be part of a continuous role of material that eventually becomes a layer, or one of a number of layers, in a printed circuit board such as the one shown in  FIG. 1 . The panel of material  210  could also be called a substrate on which the electrical traces, pads, and through holes are formed.  
       FIG. 4  is a side view of the panel of material  210  after depositing conductive material on the first major surface  211  and the second major surface  212  of the indented panel  210 , according to an embodiment of this invention. As shown in  FIG. 4 , the first major surface  211  has a conductive layer  311  placed thereon, and the second major surface  212  has a second layer of conductive material  312  deposited thereon. The deposited conductive material surfaces  311  and  312  fill the indentations or features which are produced by the surfaces  241  and  242  of the first indenting roller  221  and the second indenting roller  222 , respectively (as shown in  FIG. 2 ).  
       FIG. 5  shows a side view of a grinder mechanism removing at least a portion of the plate for deposited conductive material  311  from the first major surface  211  of the panel of material  210 , according to an embodiment of this invention. The panel of material  210  is placed on a flat, stiff plate, depicted by reference numeral  510 . The flat, stiff plate  510  includes a flat, stiff surface  511 . The grinding mechanism  500  includes a grinder  520  which has a grinding surface  540 . The grinder  520  rotates with respect to the first major surface  211  of the panel of material  210  as it is passed over the flat, stiff plate  510 . The grinding mechanism also includes a first load roller  524  and a second load roller  526  positioned on either side of the grinder  520 . The first load roller  524  produces a load depicted by an arrow having a reference number  534 . Similarly the second load roller  526  produces a load depicted by the arrow carrying a reference numeral  536 . The flat, stiff plate produces forces which counter the loads  534  and  536 . As shown in  FIG. 5 , a load  535  counter acts the load  534  while a load  537  counteracts the load  536 . The load rollers  526 ,  524  flatten the surface of the substrate or panel of material  210  as it is being ground or as the portion of the conductive surface  311  is removed from the first major surface  211  of the panel of material  210 . By removing a portion of the conductive material  311 , conductive material only remains in the indentations or various features formed in the indentations in the panel of material  210 .  
      In some embodiments of the invention the grinding mechanism  500  is set at a level so that a portion of the electrically conductive material  311 , as well as a portion of the first major surface  211 , are removed by the grinder  520 . This assures that the conductive material that remains in the features or indentations within the panel of material  210  are electrically isolated from one another or are separated by non-conductive material. As mentioned previously, the panel of material  210  is made of a non-conductive plastic, such as ABF plastic, thermoplastic or thermoset plastic. It should also be noted that when both sides of the panel of material  210  are indented, both sides are treated as shown in  FIG. 5 . In other words, a portion of the electrically conductive material  312  is removed from the second major surface  212  of the panel of material  210 . Also, in some embodiments, the grinding process or grinder  520  may be set to also remove a portion of the second major surface  212 . As shown in  FIG. 5 , the second major surface  212  has already had the portion of the conductive layer  312  removed. In other words, the second major surface  212  was already treated in the panel of material  210  shown in  FIG. 5 .  
       FIG. 6  is a perspective view of an indenting roller  600  which carries a plate  610  having an intending surface  620 , according to an embodiment of this invention. The roller  600  is a continuous roller which has a width that roughly corresponds to the width of the panel of material  210 . Roller  600  includes a plate  610 . The plate  610  is removable from the roller  600 . In other words, the plate  610  is interchangeable with other plates that can be placed on the roller  600 . The plate  610  includes a surface  620 . The surface  620  includes features which are rolled into the major surfaces of the panel of material  210  (shown in  FIG. 2 ). The features result in indentations in the first major surface  211  or the second major surface  212  of the panel of material  210 . The plate  610  is interchangeable with other plates because as the roller  600  and the plate  610  roll over the panel of material  210  the features  620  on the surface of the plate  610  eventually wear to the point where the indentations produced by the feature  620  are unacceptable.  
      A new plate  610  having the same pattern of feature  620  can then be placed upon the roller  600  to continue the operation of forming printed circuit boards such as printed circuit board  100 , from the panel of material  210 . A plate  610  is formed from a mold of a master surface. A master surface having features similar to the features  620  on plate  610  is first formed and qualified. Once formed and qualified, a mold is then formed of the plate or of the master. A plate  610  is formed having the feature  620  by forming the plate from the mold. In some instances the original master is referred to as the father, the mold from the master or father is referred to as the mother and the plate that is formed from the mother is referred to as the son. Therefore as the plates, such as plate  610  wear, the plate  610  can be replaced with another son made from the mold or mother. Multiple mothers can be made from the master and multiple sons can be made from each mold or mother. As a result, there is very little wear on the master and the master will last for a long time. It should be noted that the indentation process can also be done on a single side of a panel of material  610 .  FIG. 7  shows such an arrangement.  
       FIG. 7  is a front view of a roller  700  having a plate  710 , according to an embodiment of this invention. The plate  710  includes feature  720 . The plate  710  is removable and interchangeable so that it may be changed out with respect to the roller  700 . As shown in  FIG. 7 , the roller  700  is used to indent a panel of material  210  having a first major surface  211  and a second major surface  212 . Specifically, the roller  700  is being used to indent the first major surface  211  of the panel of material  210 . In the front of the roller  710  is a load roller  734 . The load roller  734  produces a localized load on the panel of material  210  in the area of the indenting roller  700 . The load roller  734  flattens the panel of material  210  against a flat stiff plate  740  and specifically against a surface  741  of the flat stiff plate  740 . The end result is that the roller  700  produces indentations on a single side associated with the first major surface  211  of the panel of material  210 . The feature  720  correspond to channels, through holes and pads associated with one particular layer of a printed circuit board in a finished printed circuit board. The features formed in the first major surface  211  of the panel of material  210  are filled with conductive material and then ground, as discussed with respect to  FIGS. 2-5  above. The second major surface  212  of the panel of material  210  can be similarly treated, plated and ground so that the panel of material has two surfaces of electrical traces. Another option is to leave the panel  210  having a single surface with indentations and traces and pads filled with conductive material.  
       FIGS. 8-10  are cross-sectional side views of a panel of material during the various stages of forming a layer or two layers of a printed circuit board.  FIG. 8  is a cross-sectional side view of a portion of a panel of material  210  after the panel has been indented, according to an embodiment of this invention. As shown in  FIG. 8 , the first major surface  211  has been indented with a channel  810  that corresponds to a trace in electrical circuit. The channel  810  occurs in the first major surface  211  of the panel of material  210 . Also formed by the indentation process is a pad  812  and a through opening  814  and a pad  816 . Pads  812  and  816  correspond to the through opening  814 . Pad  812  is positioned or in the first major surface  211  of the panel of material. Pad  816  is in the second major surface  212  of the panel of material. The through hole  814  extends from the first pad  812  to the second pad  814 . The through hole  814  extends through the panel of material. Another channel  818  is also formed in the second major surface  212  of the panel of material. It should be noted that the channel  810  corresponds to a trace and the channel  818  also corresponds to an electrical trace in a finished printed circuit board, such as the printed circuit board  100  shown in  FIG. 1 . The trace  810  is wider than the trace  818 , since the trace  810  occurs along the cross-sectional cut and the trace  818  is shorter since the cross-sectional cut through the panel of material  210  crosses the electrical trace  818 .  
       FIG. 9  shows the panel of material  210  after the first major surface  211  and the second major surface  212  have had conductive material  311  deposited on the first major surface  211  and conductive material  312  deposited on the second major surface  212  of the panel of material, according to an embodiment of this invention. As mentioned above the conductive material  311 ,  312  can be deposited in any number of ways. The end result is that the channels  810 ,  818  and the pads  812 ,  816  and the through hole  814  are all completely filled with conductive material  311 ,  312 . It should be noted that the electrically conductive material  311 ,  312  is the same. Furthermore, it should be noted that the conductive material  311 ,  312  can be plated on to the pad of material, and in that case, the first major surface  211  and the second major surface  212  are plated or have electrically conductive material  311 ,  312  placed on both sides of the panel of material simultaneously. If other processes are used the first major surface  211  may have to have their electrically conductive material  311  deposited thereon in a first operation and the second major surface  212  of the panel of material  210  may have to have electrically conductive material  312  added in a separate operation.  
       FIG. 10  is a cross-sectional side view of the portion of the indented panel of material  210  after a portion of the electrically conductive material  311 ,  312  has been removed, according to an embodiment of this invention. The end result is that the indentations for traces  810 ,  818  are now filled with electrically conductive material  311 ,  312  and are separated from other traces and other electrical features of the panel by insulative material of the panel of material  210 . Thus the channels  810  and  818  result in electrical traces  1010  and  1018 . Also formed is a via  1014  within the opening  814  in the panel of material  210  as well as pads  1012  and  1016  on each end of the via  1014 . Pad  1012  is formed in the indentation  812  and pad  1016  is formed in the indentation  816 . All electrically conductive features are isolated from other features. As mentioned previously, a portion of the electrically conductive material  311 ,  312  can be removed in addition to a portion of the first major surface  211  and the second major surface  212  so as to assure that the features formed are located within the various indentations  810 ,  818 ,  812 ,  816 . It is also worthy of note that the traces  1010 ,  1018  and the pads  1012 ,  1016  are flush with respect to the first major surface  211  and the second major surface  212  of the panel of material. In other words, the electrical traces  1010 ,  1018  are not on top of the first major surface  211  and the second major surface  212  of the panel of material  210 . Similarly the pads  1012 ,  1016  are also not atop the first major surface  211  and the second major surface  212  of the panel  210 , but rather are flush with the first major surface  211  and the second major surface  212 . It should be noted that features are formed on two surfaces of the panel of material  210  as shown in  FIG. 10 . Thus, a single panel of material or a single layer of material yields two layers of electrical traces or electrical features. As a result, a printed circuit board having two layers of features is much thinner than conventional printed circuit boards since the panel of material  210  includes two layers of electrical features. In conventional design, a print circuit board having two layers of electrical features would require two panels of material or two layers of insulated material. It should also be noted that indentations can be made on a single surface and so a single layer of electrical features can be formed on just one side of a panel of material  210  to form a single surface printed circuit board.  
      An advantage of forming two layers of electrical features on a single panel of material  210  is that it is not necessary to join two layers to form the required printed circuit.  
      An electrical device includes a sheet of insulative material having indentations or grooves  810 ,  812  therein. The sheet of insulative material has a first planar surface  211 , and a second planar surface  212 . A conductive material  311  is positioned within the indentations or grooves  810 ,  812 . The conductive material within the indentations or grooves forms electrical traces  1010 ,  1012  in the electrical device. The conductive material  311  within the indentations or grooves  810 ,  812  fills the groove and includes a surface coplanar with at least one of the first planar surface  211  or the second planar surface  212 . In some embodiments, the first planar surface  211  of the sheet of the insulative material or panel of material  210  has indentations or grooves  810 ,  812  therein, and the second planar surface  212  of the insulative material has indentations or grooves therein. The indentations or grooves  810 ,  812  in the first planar surface  211  and the second planar surface  212  of the sheet of the insulative material  210  are filled with the conductive material. The conductive material  311 ,  312  within the grooves in the first planar surface  211  includes a surface coplanar with the first planar surface. The conductive material  312  within the grooves  816 ,  818  in the second planar surface  212  also includes a surface coplanar with the second planar surface.  
      The electrical device includes an exterior surface  211 . The exterior surface  211  of the electrical device includes features that are flush with the exterior surface  211  of the device. In some embodiments, the features that are flush with the exterior surface  211  of the device are pads  1012 . The exterior surface  211  is ground or formed by grinding.  
      The electrical device includes an exterior surface  211 . The exterior surface  211  of the electrical device includes features that are flush with the exterior surface  211  of the device. In some embodiments, the features that are flush with the exterior surface  211  of the device are pads  1012 . The exterior surface  211  is ground or formed by grinding.  
       FIG. 11  is a cross-sectional side-view of several panels of material  1110 ,  1112 ,  1114  joined together to form a multi-layer electrical device  1100 , according to an embodiment of this invention. Multi-layer electrical device  1100  includes six layers of electrical traces in the three panels of material  1110 ,  1112 ,  1114 . The electrical traces are formed in indentations or grooves  1130 ,  1131 ,  1132  associated with the first panel of material  1110 , and in grooves  1140 ,  1141 ,  1142  or indentations formed in the second panel of material  1112 . The first panel of material  1110  includes a first major surface  1120  and a second major surface  1121 . The second panel of material  1112  includes a first major surface  1122  and a second major surface  1123 . The third panel of material  1114  includes a first major surface  1124  and a second major surface  1125 . All of the major surfaces  1120 ,  1121 ,  1122 ,  1123 ,  1124 ,  1125  are planar surfaces or substantially planar surfaces having the grooves or indentations therein.  
      The grooves or indentations are only numbered for two of the panels of material  1110 ,  1112 . The grooves or indentations were not numbered for the panel of material  1114  for the sake of clarity. The grooves or indentations associated with the first panel of material  1110 , the second panel of material  1112 , and the third panel of material  1114 , have grooves or indentations such as grooves or indentations  1130 ,  1131 ,  1132 ,  1140 ,  1141 ,  1142 ,  1143  that are filled with an electrically conductive material  1150 . The electrically conductive material  1150  forms electrical traces in the first panel of material  1110 , the second panel of material  1112 , and the third panel of material  1114  as well as between the various panels of material  1112 ,  1114 ,  1110 . As can be seen by electrical device  1100 , its form can be much thinner than other electrical devices which have a layer of electrical traces on each layer within the electrical device.  
      As shown in  FIG. 11 , each layer of the electrical device which corresponds to a panel of material  1110 ,  1112 ,  1114  includes two layers of electrical devices or electrical traces. Further advantage of this multi-layer electrical device  1100  shown in  FIG. 11  is that certain imprecise processes are no longer necessary to form the printed circuit board. For example, forming a via generally included forming a drill opening within the multi-layer device and hitting various pads in various layers of the printed circuit board. As shown in  FIG. 11 , a multi-layer printed circuit board  1100  formed using the systems and devices as well as the method described in the figures of this application will no longer require drilling through several layers of printed circuit board. Another advantage of this invention is that the traces can be more closely spaced and the traces can be made smaller since the various layers formed are merely placed together and then bonded.  
      In some embodiments, the electrical device has a first sheet and a second sheet of insulative material formed from a first panel of material  1110  and a second panel of material  1112 . Both the first sheet and the second sheet of insulative material have a first planar surface  1120 ,  1122  and a second planar surface  1121 ,  1123  with grooves or indentations  1130 ,  1131 ,  1132 ,  1140 ,  1141 ,  1142 ,  1143  therein that are filled with a conductive material  1150 . The conductive material  1150  forms electrical traces in the first sheet of insulative material and the second sheet of insulative material when the first sheet of insulative material is attached to the second sheet of insulative material. The two sheets, when attached, form a multi-layered electrical device  1110 .  
       FIG. 12  is a flow diagram showing a method of forming a conductive circuit on a non-conductive substrate or panel  1200 , according to an embodiment of this invention. The method for forming a conductive circuit on a substantially non-conductive substrate  1200  includes indenting a major surface of a substrate with a plurality of features  1210 , plating the major surface and the indentations formed with a conductive layer  1212 , and removing a portion of the conductive layer leaving at least one of the plurality of the indentations filled with conductive material separated from at least one other of the plurality of the indentations filled with conductive material separated by non-conductive material  1214 . The major surface of the substrate is indented with a roller. In some embodiments, the major surface of the substrate is indented with a plurality of indenting devices. Removing a portion of the conductive layer  1212  includes grinding a portion of the conductive layer  311  (shown in  FIG. 5 ). A conductive circuit is formed on a substantially non-conductive substrate, according to the method set forth in this paragraph.  
       FIG. 13  is a flow diagram showing another method of forming a conductive circuit on a non-conductive substrate or panel  1300 , according to an embodiment of this invention. The method for forming a conductive circuit on a substantially non-conductive substrate  1300  also includes indenting a first major surface of a first substrate with a first plurality of features  1310 , indenting a second major surface of a first substrate with a second plurality of features  1312 , plating the first major surface and the indentations formed in the first major surface with a conductive layer  1314 , and plating the second major surface and the indentations formed in the second major surface with a conductive layer  1316 . The method  1300  further includes removing a portion of the conductive layer on the first major surface leaving at least one of the plurality of the indentations in the first major surface filled with conductive material separated from at least one other of the plurality of the indentations in the first major surface filled with conductive material separated by non-conductive material  1318 , and removing a portion of the conductive layer on the second major surface leaving at least one of the plurality of the indentations in the second major surface filled with conductive material separated from at least one other of the plurality of the indentations in the second major surface filled with conductive material separated by non-conductive material  1320 .  
      Once the panel has been formed with multiple layers, or once a panel is formed having two layers and that is what is desired for a final product, the panel of material  210  will be sliced into individual printed circuit boards such as printed circuit board  100  shown in  FIG. 1 . As mentioned previously, there are many types of printed circuit boards and  FIG. 1  only shows one type of printed circuit board. The invention contemplates manufactured printed circuit boards for all applications.  
       FIG. 14  is a top view of a panel of material  210  and an indenting system  1400  including a set of rollers  1410  and a set of rollers  1420  for forming indented features on the panel of material  210 , according to an embodiment of this invention. The first set of rollers  1410  includes individual rollers  1411 ,  1412 ,  1413 ,  1414 ,  1415 , and  1416 . The second set of rollers  1420  includes individual rollers  1421 ,  1422 ,  1423 ,  1424 , and  1425 . Each of the individual rollers  1411 ,  1412 ,  1413 ,  1414 ,  1415 ,  1416 ,  1421 ,  1422 ,  1423 ,  1424 , and  1425  have features thereon which are used to indent the panel of material  210  to form grooves which are later filled per the previous discussion with respect to  FIGS. 1-13 . Each of the individual rollers in the first set of rollers  1410  and the second set of rollers  1421  need not be circular in cross-section. As shown in  FIG. 14  the cross-sectional areas can be circular as depicted by reference numeral  1430  hexagonal as depicted by reference number  1432  or octagonal as depicted by reference numeral  1434 . These are not the only types of cross-sectional areas that are contemplated. A roller having any cross-section that will produce an indentation or groove in the panel of material  210  is within the scope of this invention.  
       FIG. 15  is a front view of an indenting system  1500  including a first set of rollers  1510  and a second set of rollers  1530  for forming indented features on grooves on two sides of a panel of material  210 , according to an embodiment of this invention. The first set of rollers  1510  includes individual rollers  1511 ,  1512 ,  1513 ,  1514 ,  1515 ,  1516 ,  1517 ,  1518 ,  1519 ,  1520  and  1521 . The second set of rollers  1530  includes individual rollers  1531 ,  1532 ,  1533 ,  1534 ,  1535 ,  1536 ,  1537 ,  1538 ,  1539 ,  1540  and  1541 . The first set of rollers  1510  impact the first major surface  211  of the substrate of the panel of material  210 . The second set of rollers  1530  impacts and indents or forms grooves in the second major surface  212  of the panel of material  210 . Again the individual rollers or indenters need not have a circular cross-section but can have cross-sections of any type that will form indentations within the first major surface  211  and the second major surface  212  of the panel of material  210 .  
       FIG. 16  is a side view of a panel of material  210  passing through a set of rollers  1610  to indent one side of the panel of material  210 , according to an embodiment of this invention. The set of rollers  1610  includes an indenting roller  1620  having features on a surface  1621  of the roller used to form channels, indentations or grooves in the first major surface  211  of the panel of material  210 . The set of rollers  1610  also includes a first load roller  1630  and a second load roller  1632 . The first load roller  1630  and the second load roller  1632  produce loads to flatten the panel of material  210  near or proximate the indentation roller  1620 . The panel  210  is placed over a flat, stiff plate  510 . The flat, stiff plate  510  includes a flat, stiff surface  511  which produces forces counteracting the forces produced by the load rollers  1630 ,  1632 . The force produced by the load rollers  1630  and  1632  are depicted by arrows carrying the reference numerals  1650  and  1652 . The counteracting forces produced by the stiff, flat plate  510  are shown by arrows carrying the reference numerals  1660  and  1662 .  
       FIG. 17  is a side view of a grinder mechanism  1700  for removing at least a portion of the plated material from the first major surface  211  and from the second major surface  212  of the panel of material substantially simultaneously  210 , according to an embodiment of this invention. The grinding mechanism  1700  includes a first grinding wheel  1710  and a second grinding wheel  1720 . The first grinding wheel  1710  removes material from the top surface associated with the first major surface  211  and the second grinding wheel  1720  removes material associated with the second major surface  212  of the panel of material  210 . The grinding wheels  1710  and  1720  work substantially simultaneously to remove material such as electrically conductive material that has been plated on the surfaces  211  and  212 . The grinding mechanism  1700  also includes a first pair of opposed load rollers  1730  and a second pair of opposed load rollers  1740  which flatten the panel of material  210  near the first grinding wheel  1710  and the second grinding wheel  1720 .  
       FIG. 18  is a side view of a grinder mechanism  1800  for removing at least a portion of the plated material from two major surfaces of the panel  210  substantially simultaneously, according to an embodiment of this invention. The grinding mechanism  1800  includes a first set of a plurality of grinders  1810  and a second set of a plurality of grinders  1820 . The first set of the plurality of grinders  810  is used to remove material from the first major surface  211  of the panel of material  210 . The second set of grinding devices  1820  removes material associated with the second major surface  212  of the panel of material  210 .  
       FIG. 19  is a schematic view of a system  1900  for forming printed circuit boards, according to an embodiment of this invention. The system includes an indenter  1910 , a plater or depositor of conductive material  1912 , and a removal tool  1914  for removing portions of conductive material from major surfaces of a substrate or panel of material  210  (shown in  FIG. 2 ).  
      Now, with respect to  FIG. 19  and  FIGS. 2-18 , a system for making a conductive circuit on a substantially non-conductive substrate includes an indenter  1910  that forms a plurality of indentations on a first major surface  211  of the substrate  210 , a plater that plates conductive material  311 ,  312  on the major surface  211 ,  212  of the substrate  210  (shown in  FIG. 2 ) and within the indentations formed in the major surface  211 ,  212  of the substrate  210 , (shown in  FIG. 2 ) and a removal tool or grinder  1914  that removes a portion of the conductive material plated on the major surface of the substrate to leave conductive material within the indentations in the major surface of the substrate. The conductive material  311 ,  312  (shown in  FIG. 3 ) within at least some of the plurality of indentations is separated from the conductive material within some of the other indentations by non-insulative material. The grinder  1914  removes a portion of the conductive material  311 ,  312  (shown in  FIG. 3 ) within the plurality of indentations. The grinder  1914  also removes a portion of the conductive material within the plurality of indentations to form a planar surface including non-conductive material and conductive material. The indenter  1910  includes a plate having a negative of the indentations in the substrate. In some embodiments, the indenter  1910  is a roller. The roller includes an interchangeable plate having a negative of the indentations in the substrate. The indentations include at least one channel, at least one pad, or at least one via. In some embodiments, the indenter  1910  includes a plurality of planar surfaces. The indenter  1910 , in some embodiments, has multiple sides.  
      A system  1900  for making a conductive circuit on a substantially non-conductive substrate  1900  includes a first roller apparatus that forms a plurality of indentations on a first major surface of the substrate  221  (shown in  FIG. 2 ), and a second roller apparatus that forms a plurality of indentations on a second major surface of the substrate  222  (shown in  FIG. 2 ). The system for making a conductive circuit on a substantially non-conductive substrate further includes a plater  1912  that plates conductive material on the first major surface of the substrate  211  (shown in  FIG. 2 ) and on the second major surface of the substrate  212  (shown in  FIG. 2 ) and within the indentations formed in the first major surface of the substrate and in the second major surface of the substrate  210  (shown in  FIG. 2 ), and a grinder apparatus  1914  that removes a portion of the conductive material plated on the first major surface of the substrate leaving conductive material within the indentations in the first major surface of the substrate, and removes a portion of the conductive material plated on the second major surface of the substrate leaving conductive material within the indentations in the second major surface of the substrate, wherein the conductive material within at least some of the plurality of indentations is separated from the conductive material within some of the other indentations by non-insulative material. In some embodiments, the grinder apparatus includes a plurality of grinders. In some embodiments of the invention, the first roller apparatus is comprised of a plurality of rollers.  
      Although the invention has been described above using a printed circuit card as an example of a substrate, it should be noted that the invention contemplates application to any type of substrate. A substrate includes a wafer and a die within a package.  FIG. 20  is a top view of a wafer  2000 , according to an embodiment of this invention. The wafer  2000  shown has markings thereon indicating the portions of the wafer that will be individual dies or chips. In reality, the markings on the surface of the wafer  2000  are not present.  FIG. 21  is a top view of a die  2100  within a package  2110 , according to an embodiment of this invention. The die  2100  is one type of substrate that this invention includes and the package  2110  is another type of substrate the invention includes.  
      The foregoing description of the specific embodiments reveals the general nature of the invention sufficiently so that others can, by applying current knowledge, readily modify and/or adapt it for various applications without departing from the generic concept, and therefore such adaptations and modifications are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments.  
      It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Accordingly, the invention is intended to embrace all such alternatives, modifications, equivalents and variations as fall within the spirit and broad scope of the appended claims.