Abstract:
The present invention is directed to a method forming conductive templates that includes providing a substrate; forming a mesa on the substrate; and forming a plurality of recessions and projections on the mesa with a nadir of the recessions comprising electrically conductive material and the projections comprising electrically insulative material. It is desired that the mesa be substantially transparent to a predetermined wavelength of radiation, for example ultraviolet radiation. As a result, it is desired to form the electrically conductive material from a material that allows ultraviolet radiation to propagate therethrough. In the present invention indium tin oxide is a suitable material from which to form the electrical conductive material.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a Continuation of U.S. patent application Ser. No. 10/706,537 filed on Nov. 12, 2003, which is hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The field of invention relates generally to imprint lithography. More particularly, the present invention is directed to reducing the time required to fill the features of a template with imprinting material during imprint lithography processes. 
         [0003]    Micro-fabrication involves the fabrication of very small structures, e.g., having features on the order of micro-meters or smaller. One area in which micro-fabrication has had a sizeable impact is in the processing of integrated circuits. As the semiconductor processing industry continues to strive for larger production yields while increasing the circuits per unit area formed on a substrate, micro-fabrication becomes increasingly important. Micro-fabrication provides greater process control while allowing increased reduction of the minimum feature dimension of the structures formed. Other areas of development in which micro-fabrication has been employed include biotechnology, optical technology, mechanical systems and the like. 
         [0004]    An exemplary micro-fabrication technique is shown in U.S. Pat. No. 6,334,960 to Willson et al. Willson et al. disclose a method of forming a relief image in a structure. The method includes providing a substrate having a transfer layer. The transfer layer is covered with a polymerizable fluid composition. A mold makes mechanical contact with the polymerizable fluid. The mold includes a relief structure, and the polymerizable fluid composition fills the relief structure. The polymerizable fluid composition is then subjected to conditions to solidify and to polymerize the same, forming a solidified polymeric material on the transfer layer that contains a relief structure complimentary to that of the mold. The mold is then separated from the solid polymeric material such that a replica of the relief structure in the mold is formed in the solidified polymeric material. The transfer layer and the solidified polymeric material are subjected to an environment to selectively etch the transfer layer relative to the solidified polymeric material such that a relief image is formed in the transfer layer. The time required and the minimum feature dimension provided by this technique are dependent upon, inter alia, the composition of the polymerizable material. 
         [0005]    It is desired, therefore, to provide a technique that decreases the time required to fill a feature of an imprint lithography template. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention is directed to a conductive template and of a method forming conductive templates that includes providing a substrate; forming a mesa on the substrate; and forming a plurality of recessions and projections on the mesa with a nadir of the recessions comprising electrically conductive material and the projections comprising electrically insulative material. It is desired that the mesa be substantially transparent to a predetermined wavelength of radiation, for example ultraviolet radiation. As a result, it is desired to form the electrically conductive material from a material that allows ultraviolet radiation to propagate therethrough. In the present invention indium tin oxide is a suitable material from which to form the electrical conductive material. However, indium tin oxide is difficult to pattern due to its resistance to etch. Nonetheless, the present method provides a manner in which to form a conductive template with indium oxide suitable for use in imprint lithography. These other embodiments are discussed more fully below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0007]      FIG. 1  is a perspective view of a lithographic system in accordance with the present invention; 
           [0008]      FIG. 2  is a simplified elevation view of a lithographic system shown in  FIG. 1 ; 
           [0009]      FIG. 3  is a simplified representation of material from which an imprinting layer, shown in  FIG. 2 , is comprised before being polymerized and cross-linked; 
           [0010]      FIG. 4  is a simplified representation of cross-linked polymer material into which the material shown in  FIG. 3  is transformed after being subjected to radiation; 
           [0011]      FIG. 5  is a simplified elevation view of a mold spaced-apart from the imprinting layer, shown in  FIG. 1 , after patterning of the imprinting layer; 
           [0012]      FIG. 6  is a top down view showing an array of droplets of imprinting material deposited upon a region of the substrate shown above in  FIG. 2  in accordance with a first embodiment of the present invention; 
           [0013]      FIG. 7  is a simplified schematic view of cantilevering impingement of a mold, shown in  FIG. 2 , impinging upon the array of droplets, shown in  FIG. 6 , in accordance with one embodiment of the present invention; 
           [0014]      FIGS. 8-11  are top down views showing the compression of droplets, shown above in  FIG. 6 , employing cantilevering impingement of mold, shown in  FIG. 7 ; 
           [0015]      FIG. 12  is a bottom up view of a mold having individually addressable electrical conductors in accordance with an alternate embodiment of the present invention; 
           [0016]      FIG. 13  is a side cross-sectional view of the template shown in  FIG. 12 ; 
           [0017]      FIG. 14  is a top down view of a substrate employed to fabricate the template shown in accordance with yet another embodiment of the present invention; 
           [0018]      FIG. 15  is a side cross-sectional view of a region of the substrate, shown in  FIG. 14 , taken across lines  15 - 15 ; 
           [0019]      FIGS. 16-23  are side cross-sectional views of the region shown in  FIG. 15  demonstrating the various processes employed to fabricate the template shown in  FIG. 13 ; 
           [0020]      FIG. 24  is a top down view of the region shown in  FIG. 6 , with the droplets of imprinting material disposed in an array according to yet a fourth embodiment of the present invention; 
           [0021]      FIG. 25  is a top down view showing the compression of droplets, shown above in  FIG. 24 , employing mold, shown in  FIG. 2 , in accordance with a fifth embodiment of the present invention; 
           [0022]      FIG. 26  is a cross-sectional view of a template in accordance with a sixth embodiment of the present invention; 
           [0023]      FIG. 27  is a top down view of a substrate employed to fabricate the template, shown in  FIG. 26 , in accordance with a seventh embodiment of the present invention; 
           [0024]      FIG. 28  is a cross-sectional view of a region of the substrate shown in  FIG. 27  taken along lines  28 - 28 ; and 
           [0025]      FIGS. 29-30  are cross-sectional views of the region shown in  FIG. 28  demonstrating the various processes employed to fabricate the template shown in  FIG. 26 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0026]      FIG. 1  depicts a lithographic system  10  in accordance with one embodiment of the present invention that includes a pair of spaced-apart bridge supports  12  having a bridge  14  and a stage support  16  extending therebetween. Bridge  14  and stage support  16  are spaced-apart. Coupled to bridge  14  is an imprint head  18 , which extends from bridge  14  toward stage support  16  and provides movement along the Z-axis. Disposed upon stage support  16  to face imprint head  18  is a motion stage  20 . Motion stage  20  is configured to move with respect to stage support  16  along X- and Y-axes. It should be understood that imprint head  18  may provide movement along the X- and Y-axes, as well as the Z-axis, and motion stage  20  may provide movement in the Z-axis, as well as the X- and Y-axes. An exemplary motion stage device is disclosed in U.S. Pat. No. 6,900,881, which is assigned to the assignee of the present invention, and which is incorporated by reference herein in its entirety. A radiation source  22  is coupled to system  10  to impinge actinic radiation upon motion stage  20 . As shown, radiation source  22  is coupled to bridge  14  and includes a power generator  23  connected to radiation source  22 . Operation of system is typically controlled by a processor  25  that is in data communication therewith. 
         [0027]    Referring to both  FIGS. 1 and 2 , connected to imprint head  18  is a template  26  having a mold  28  thereon. Mold  28  includes a plurality of features defined by a plurality of spaced-apart recessions  28   a  and protrusions  28   b.  The plurality of features defines an original pattern that is to be transferred into a substrate  30  positioned on motion stage  20 . To that end, imprint head  18  and/or motion stage  20  may vary a distance “d” between mold  28  and substrate  30 . In this manner, the features on mold  28  may be imprinted into a flowable region of substrate  30 , discussed more fully below. Radiation source  22  is located so that mold  28  is positioned between radiation source  22  and substrate  30 . As a result, mold  28  is fabricated from material that allows it to be substantially transparent to the radiation produced by radiation source  22 . To that end, mold  28  may be formed from materials that includes quartz, fused-silica, silicon, sapphire, organic polymers, siloxane polymers, borosilicate glass, fluorocarbon polymers or a combination thereof. Further template  26  may be formed from the aforementioned materials, as well as metal. 
         [0028]    Referring to both  FIGS. 2 and 3 , a flowable region, such as an imprinting layer  34 , is disposed on a portion of surface  32  that presents a substantially planar profile. An exemplary flowable region consists of imprinting layer  34  being deposited as a plurality of spaced-apart discrete droplets  36  of material  36   a  on substrate  30 , discussed more fully below. An exemplary system for depositing droplets  36  is disclosed in U.S. Pat. No. 6,926,929, which is assigned to the assignee of the present invention, and which is incorporated by reference herein in its entirety. Imprinting layer  34  is formed from a material  36   a  that may be selectively polymerized and cross-linked to record the original pattern therein, defining a recorded pattern. An exemplary composition for material  36   a  is disclosed in U.S. Pat. No. 7,157,036, which is incorporated by reference in its entirety herein. Material  36   a  is shown in  FIG. 4  as being cross-linked at points  36   b,  forming cross-linked polymer material  36   c.    
         [0029]    Referring to  FIGS. 2 ,  3  and  5 , the pattern recorded in imprinting layer  34  is produced, in part, by mechanical contact with mold  28 . To that end, distance “d” is reduced to allow imprinting droplets  36  to come into mechanical contact with mold  28 , spreading droplets  36  so as to form imprinting layer  34  with a contiguous formation of material  36   a  over surface  32 . In one embodiment, distance “d” is reduced to allow sub-portions  34   a  of imprinting layer  34  to ingress into and to fill recessions  28   a.    
         [0030]    To facilitate filling of recessions  28   a,  material  36   a  is provided with the requisite properties to completely fill recessions  28   a  while covering surface  32  with a contiguous formation of material  36   a.  In the present embodiment, sub-portions  34   b  of imprinting layer  34  in superimposition with protrusions  28   b  remain after the desired, usually minimum, distance “d”, has been reached, leaving sub-portions  34   a  with a thickness t 1  and sub-portions  34   b  with a thickness t 2 . Thicknesses “t 1 ” and “t 2 ” may be any thickness desired, dependent upon the application. Typically, t 1  is selected so as to be no greater than twice the width u of sub-portions  34   a,  i.e., t 1 ≦2u, shown more clearly in  FIG. 5 . 
         [0031]    Referring to  FIGS. 2 ,  3  and  4 , after a desired distance “d” has been reached, radiation source  22  produces actinic radiation that polymerizes and cross-links material  36   a,  forming cross-linked polymer material  36   c.  As a result, the composition of imprinting layer  34  transforms from material  36   a  to cross-linked polymer material  36   c,  which is a solid. Specifically, cross-linked polymer material  36   c  is solidified to provide side  34   c  of imprinting layer  34  with a shape conforming to a shape of a surface  28   c  of mold  28 , shown more clearly in  FIG. 5 . After imprinting layer  34  is transformed to consist of cross-linked polymer material  36   c,  shown in  FIG. 4 , imprint head  18 , shown in  FIG. 2 , is moved to increase distance “d” so that mold  28  and imprinting layer  34  are spaced-apart. 
         [0032]    Referring to  FIG. 5 , additional processing may be employed to complete the patterning of substrate  30 . For example, substrate  30  and imprinting layer  34  may be etched to transfer the pattern of imprinting layer  34  into substrate  30 , providing a patterned surface  34   c.  To facilitate etching, the material from which imprinting layer  34  is formed may be varied to define a relative etch rate with respect to substrate  30 , as desired. 
         [0033]    Referring to  FIGS. 2 ,  3  and  6 , for molds having very dense features, e.g., recessions  28   a  on the order of nanometers, spreading droplets  36  over a region  40  of substrate  30  in superimposition with mold  28  to fill the recessions  28   a  can require long periods of time, thereby slowing throughput of the imprinting process. To facilitate an increase in the throughput of the imprinting process droplets  36  are dispensed to minimize the time required to spread over substrate  30  and to fill recessions  28   a.  This is achieved by dispensing droplets  36  as a two-dimensional matrix array  42  so that a spacing, shown as S 1  and S 2 , between adjacent droplets  36  is minimized. As shown, droplets  36  of matrix array  42  area arranged in six columns n 1 -n 6  and six rows m 1 -m 6 . However, droplets  36  may be arranged in virtually any two-dimensional arrangement on substrate  30 . What is desired is maximizing the number of droplets  36  in matrix array  42 , for a given total volume, V t , of imprinting material  36  necessary to form a desired patterned layer. This minimizes the spacing S 1  and S 2  between adjacent droplets. Further, it is desired that each of droplets  36  in the subset have substantially identical quantities of imprinting material  36   a  associated therewith, defined as a unit volume, V u  Based upon these criteria, it can be determined that the total number, n, of droplets  36  in matrix array  42  may be determined as follows: 
         [0000]        n=V   t   /V   u    (1) 
         [0000]    where V t l and V   u  are defined above. Assume a square array of droplets  36  where the total number, n, of droplets  36  is defined as follows: 
         [0000]        n=n   1   ×n   2    (2) 
         [0000]    where n 1  is that number of droplets along a first direction and n 2  is the number of droplets along a second direction A spacing S 1  between adjacent droplets  36  along a first direction, i.e., in one dimension, may be determined as follows: 
         [0000]        S   1   =L   1   /n   1    (3) 
         [0000]    where L 1  is the length of region  40  along the first direction. In a similar fashion, a spacing S 2  between adjacent droplets  36  along a second direction extending transversely to the first direction may be determined as follows: 
         [0000]        S   2   =L   2   /n   2    (4) 
         [0000]    where L 2  is the length of region  40  along the second direction. 
         [0034]    Considering that the unit volume of imprinting material  36   a  associated with each of droplets  36  is dependent upon the dispensing apparatus, it becomes clear that spacings S 1  and S 2  are dependent upon the resolution, i.e., operational control of the droplet dispensing apparatus (not shown) employed to form droplets  36 . Specifically, it is desired that the dispensing apparatus (not shown) be provided with a minimum quantity of imprinting material  36   a  in each of droplets  36  so that the same may be precisely controlled. In this fashion, the area of region  40  over which imprinting material  36   a  in each droplet  36  must travel is minimized. This reduces the time required to fill recessions  28  and cover substrate with a contiguous layer of imprinting material  36   a.    
         [0035]    Another problem that the present invention seeks to avoid is the trapping of gases in imprinting layer  34  once patterned surface  34   c  is formed. Specifically, in the volume  44  between spaced-apart droplets  36  of matrix array  42 , there are gases present, and droplets  36  in matrix array  42  are spread over region  40  so as to avoid, if not prevent, trapping of gases therein. To that end, in accordance with one embodiment of the present invention, a subset of droplets  36  in matrix array  42  that are compressed along a first direction by mold  28  along a first direction and subsequently compressing the remaining droplets  36  of matrix array  42  along a second direction, extending transversely to the first direction. This is achieved by cantilevering impingement of mold  28  onto droplets  36 , shown in  FIG. 8 . 
         [0036]    Referring to  FIGS. 6 ,  7  and  8 , template  26  is positioned so that surface  28   c  of mold  28  forms an oblique angle θ with respect to substrate surface  30   a  of substrate  30 , referred to as cantilevering impingement. An exemplary apparatus that facilitates formation of angle θ is disclosed in U.S. Pat. No. 6,873,087, which is incorporated by reference in its entirety herein. As a result of the cantilevering impingement of mold  28 , as a distance between mold  28  and substrate  30  decreases, a sub-portion of mold  28  will come into contact with a sub-set of droplets  36  in matrix array  42  before the remaining portions of mold  28  contact the one edge of mold  28  contact the remaining droplets  36  of matrix array  42 . As shown, mold  28  contacts all of droplets  36  associated with column n 6 , substantially concurrently. This causes droplets  36  to spread and to produce a contiguous liquid sheet  46  of imprinting material  36   a  extending from edge  40   a  of region  40  toward droplets in columns n 1 -n 5 . One edge of liquid sheet  46  defines a liquid-gas interface  46   a  that functions to push gases in volumes  44  away from edge  40   a  and toward edges  40   b,    40   c  and  40   d.  Volumes  44  between droplets  36  in columns n 1 -n 5  define gas passages through which gas may be pushed to the portion of perimeter of region  40 . In this manner, interface  46   a  in conjunction with the gas passages reduces, if not prevents, trapping of gases in liquid sheet  46 . 
         [0037]    Referring to  FIGS. 7 and 9 , as template  26  is moved toward substrate  30 , rotation of mold  28  occurs to allow imprinting material  36   a  associated with subsequent subsets of droplets  36  in columns n 4  and n 5  to spread and to become included in contiguous fluid sheet  46 . Template  26  continues to rotate so that mold  28  subsequently comes into contact with droplets  36  associated with columns n 2  and n 3  so that the imprinting material  36   a  associated therewith spreads to become included in contiguous sheet  46 , shown in  FIG. 10 . The process continues until all droplets  36  are included in contiguous sheet  46 , shown in  FIG. 11 . As can be seen, interface  46   a  has moved toward edge  40   c  so that there is an unimpeded path for the gases (not shown) in the remaining volume  44   a  of region  40  to travel thereto. This allows gases in volume  44   a  to egress from region  40  vis-à-vis edge  40   c.  In this manner, the trapping of gases in imprinting layer  34 , shown in  FIG. 5 , having surface  34   c  is reduced, if not avoided. 
         [0038]    Referring to  FIGS. 3 ,  12  and  13 , in another embodiment of the present invention, sequential spreading of droplets  36  in matrix array  42  column-by-column, as described with respect to  FIGS. 7-11  may be achieved without requiring cantilevering impingement of mold  28 . This may be achieved by employing electromagnetic forces to move imprinting material  36   a  across region  40  and/or toward mold  128 . To that end, mold  128  includes a plurality of individually addressable conductive elements, shown as q 1 -q 6  forming nadirs  118   a  of recessions  128   a  of mold  128 . Sub-portions  118   b  of body  150  flanking sub-portions  118   b  are in superimposition with protrusions  128   b  and do not include any conductive material there. Formation of mold  128  is discussed more fully below. 
         [0039]    Referring to  FIG. 14 , one manner in which to form a template includes obtaining a body  150  and identifying four regions  150   a,    150   b,    150   c  and  150   d  on which to form a template. Specifically, body  150  consists of a standard 6025 fused silica. Four templates, shown as templates  126 ,  226 ,  326  and  426 , are formed, concurrently, in four separate areas of body  150 . For simplicity of the present disclosure, fabrication of template  126  is discussed with the understanding that the discussion with respect to template  126  applies with equal weight to templates  226 ,  326  and  426 . 
         [0040]    Referring to  FIGS. 15 and 16 , body  150 , typically measures 152.4 mm on a side. Body  150  has a chrome layer  130  present on an entire side  112  thereof. A photoresist  132  layer covers chrome layer  130 . Photoresist layer  132  is patterned and developed away to expose a region  134  surrounding a central portion  136  of side  112 . Central portion  136  typically has dimensions measuring 25 mm on a side. Typically, photoresist layer  132  is patterned employing a laser writer. After photoresist layer  132  has been developed away, chrome layer  130  in superimposition with region  134  is etched away using any suitable etching techniques, e.g., ammonium nitrate or plasma etch. In this manner, a portion of body  150  in superimposition with region  134  is exposed. Thereafter, suitable post etching processes may occur, e.g., an oven bake or other cleaning processes. 
         [0041]    Assuming body  150  is formed from fused-silica, a suitable etching technique would involve a buffered oxide etch (BOE). This occurs for a sufficient amount of time to provide a desired height, h, for mesa  133 , as measured from surface  112  of body  150 , shown in  FIG. 18 . An exemplary height is 15 microns. Thereafter, the remaining portion of photoresist layer  132  is removed and any remaining portions of chrome layer  130  on central portion  136  are removed. A layer of photoresist material  134  is deposited over template  126 , shown in  FIG. 19 . Regions of photoresist material  134  in superimposition with mesa  133  are patterned and developed away to expose regions  136  of body  150 , using standard techniques, leaving patterned photoresist layer  138 , shown in  FIG. 20 . Thereafter, a layer of indium tin oxide (ITO)  140  is deposited on template  126  to cover patterned photoresist layer  138 , shown in  FIG. 21 . ITO is a suitable material for use with mold  128 , because it is electrically conductive and substantially transparent to the wavelength of radiation produced by radiation source  22 , shown in  FIG. 2 . A lift-off process is employed to remove patterned photoresist layer  138 , shown in  FIG. 20 , with all of the portions of ITO layer not in superimposition with regions  136  being removed during the lift-off process. In this fashion, a patterned ITO layer  142 , with regions  144  of body  150  being exposed, is formed, shown in  FIG. 22 . Following formation of patterned ITO layer  142 , a layer  146  of silicon oxide SiO 2    146  is deposited, shown in  FIG. 23 . This forms mold  128 , with silicon oxide layer  146  being patterned so that silicon oxide is not in superimposition with ITO material in ITO layer  142  that is in superimposition with regions  144 , shown in  FIG. 13 . In this manner, the nadir of recessions  128   a  are formed from ITO, and protrusions  128   b  are formed from SiO 2 . 
         [0042]    Referring to  FIGS. 3 ,  12  and  13 , understanding that protrusions  128   a  are formed from an electrically insulative material, it is realized that the electromagnetic field, EM 1 , proximate to recess  128   a  is greater than the electromagnetic field, EM 2 , that is proximate to protrusions  128   b.  To this end, voltage source  120  is in electrical communication with conductive elements q 1 -q 2  using any suitable coupling technique known, shown in  FIG. 12 . In the present example, conductive elements q 1 -q 6  are formed to extend beyond mold  128  and voltage source  120  is connected thereto. Furthermore, by selectively addressing the conducting elements q 1 -q 6 , selected droplets  36  may be selectively spread in virtually any manner desired, including the spread pattern discussed above with respect to  FIGS. 7-11 . 
         [0043]    Referring to  FIGS. 3 ,  24  and  25 , as discussed above, droplets  136  and  236  may be arranged in virtually any matrix array. As shown, droplets  136  and  236  are arranged in two sets. The quantity of imprinting material  36   a  in each of droplets  136  is substantially identical, and the quantity of imprinting material  36   a  in each of droplets  236  is substantially identical. The quantity of imprinting material in each of droplets  236  is substantially greater than the quantity of imprinting material  36   a  in each of droplets  136 . By arranging droplets  136  and  236  with differing quantities of imprinting material  36   a  in this fashion, it is believed that the time required to fill recessions  128   a  of mold  28  may be minimized while avoiding trapping of gases in imprinting layer  36   a,  without employing cantilevering impingement of mold  128  onto substrate  30 . Specifically, by providing droplets  136  with a minimum volume, the advantages discussed above with respect to reduced filling time of recessions  128   a  is achieved. The relatively large quantity of imprinting material  36   a,  shown in  FIG. 3 , in droplets  236 , shown in  FIG. 24 , and the location of the same increases the probability that the flow of imprinting material-gas interface  146   a  created by droplets  236  will be sufficiently forceful to drive gas toward perimeter of region  140  without trapping gas in imprinting material  36   a.    
         [0044]    Referring to  FIGS. 3 ,  12  and  24 , to further decrease the time required to spread and to pattern imprinting material  36   a  in droplets  136  and  236 , template  128  may be employed and conductive elements q 1 -q 6  may be activated sequentially, as discussed above, or concurrently. 
         [0045]    Referring to  FIGS. 3 ,  26  and  27 , were it desired to concurrently apply an electromagnetic field across the mold, template  526  may be employed. Template  526  is formed from a body  550  of a suitable material, such as fused silica. An exemplary material is standard 6025 fused silica having measurements, on a side, of approximately 152.4 mm. Four templates  526 ,  626 ,  726 , and  826  are formed, concurrently, in four separate regions  550   a,    550   b,    550   c  and  550   d,  respectively. For simplicity of the present disclosure, fabrication of template  526  is discussed with the understanding that the discussion with respect to template  526  applies with equal weight to templates  626 ,  726  and  826 . 
         [0046]    Referring to  FIGS. 28 and 29 , body  550  has a chrome layer  530  present on an entire side  512  thereof. A mesa  533  is formed on body  550  in the manner discussed above with respect to  FIGS. 16-18 . A layer of indium tin oxide (ITO)  534  is then deposited over the entire side  512  of body  550  using standard techniques, shown in  FIG. 30 . Deposited atop of the ITO layer  534  is a silicon oxide layer SiO 2  that is patterned and etched employing standard techniques to form recessions  528   a  and protrusions  528   b,  shown in  FIG. 26 . In this manner, the nadir of recessions  128   a  are formed from ITO and protrusions  528   b  are formed from ITO. Understanding that protrusions  528   a  are formed from an electrically insulative material, it is realized that the electromagnetic field, EM 1 , proximate to recess  528   a  is greater than the electromagnetic field, EM 2 , which is proximate to protrusions  528   b.  As a result, imprinting material  36   a  proximate to mold  528  is more likely to be drawn into recessions  528   a,  thereby reducing the time required to conform material  36   a  to mold  528 . 
         [0047]    The embodiments of the present invention described above are exemplary. Many changes and modifications may be made to the disclosure recited above, while remaining within the scope of the invention. For example, the use of electromagnetic filed may prove beneficial in ensuring that imprint material fully fill the features on the mold, thereby avoiding discontinuities in the imprinting layer. Such discontinuities occur when imprinting material fails to fill the recessions of the mold. This may be due to various environment and material based parameters, such as capillary attraction between a protrusion and a surface in superimposition therewith. Applying an electromagnetic field to attract imprinting material to the mold will overcome these properties. Therefore, the scope of the invention should not be limited by the above description, but instead should be determined with reference to the appended claims along with their full scope of equivalents.