Abstract:
A printhead and a method of manufacturing a printhead are provided. The printhead includes a polymeric substrate including a surface. Portions of the polymeric substrate define a liquid chamber. A material layer is disposed on the surface of the polymeric substrate. Portions of the material layer define a nozzle bore. The nozzle bore is in fluid communication with the liquid chamber.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     The present application is related to the following pending patent application: U.S. patent application Ser. No. ______ (Docket 90766) entitled A METHOD OF FORMING A PRINTHEAD, filed concurrently herewith. 
     
    
     FIELD OF THE INVENTION  
       [0002]     This invention relates generally to the formation of fluid chambers and/or passageways in polymeric substrates and the devices incorporating these substrates and, in particular to printheads incorporating polymeric substrates and the formation of these printheads.  
       BACKGROUND OF THE INVENTION  
       [0003]     Printheads having nozzle plates made from a polymer material are known. For example, U.S. Patent Application Publication No. US 2003/0052947 A1, published Mar. 20, 2003, discloses a printhead and a method for manufacturing a printhead in which a silicon substrate having a thermal element is covered with a photoresist layer or polymer material. The photoresist layer or polymer material form a barrier layer over the silicon substrate. A sandblasting process is used to make a slot on the silicon substrate. The slot forms an ink channel of the printhead. A photolithographic process is used to form a pattern on the barrier layer. The barrier layer is then etched to form ink cavities in fluid communication with the ink channel and form pillars located between the ink chambers. The barrier layer is then attached onto a polymer nozzle plate using a lamination process. The nozzles of the polymer nozzle plate are formed using a laser ablation or photoresist lithographic process.  
         [0004]     However, the polymer nozzle plate can sink when it is laminated to the barrier layer, see, for example,  FIGS. 1 and 2  of U.S. Patent Application Publication No. U.S. 2003/0052947 A1. This results in skewed ejection directions when ink is ejected from the nozzles of the polymer nozzle plate. The structural rigidity of the printhead can also be compromised especially when the printhead length approaches lengths commonly associated with page wide printheads. Additionally, alignment of the polymer nozzle plate to the structures in the silicon substrate can be difficult when the polymer nozzle plate is laminated to the silicon substrate.  
         [0005]     U.S. Pat. No. 5,291,226, issued Mar. 1, 1994, also discloses an inkjet printhead that includes a nozzle member formed from a polymer material that has been laser ablated to form inkjet orifices, ink channels, and vaporization chambers in the nozzle member. The nozzle member is then mounted to a substrate containing heating elements associated with each orifice. However, the laser ablation process is a relatively dirty process. Often, the polymer material needs to be cleaned after it has been laser ablated which adds cost and additional steps to the fabrication process. Also, it can be difficult to precisely place the features, created by the laser ablation process, over larger areas of the polymer material. Additionally, laser ablation is not a standard microelectronic process. As such, the complexity of the fabrication process, for example, the fabrication process for monolithic printheads with integrated electronics, is increased.  
       SUMMARY OF THE INVENTION  
       [0006]     According to one feature of the present invention, a method of manufacturing a printhead includes providing a polymeric substrate having a first and second surface; providing a material layer on the first surface of the polymeric substrate; providing a patterned carrier substrate on the second surface of the polymeric substrate; and removing at least some of the polymeric substrate not covered by the patterned carrier substrate using an etching process.  
         [0007]     According to another feature of the present invention, a printhead includes a polymeric substrate including a surface. Portions of the polymeric substrate define a liquid chamber. A material layer is disposed on the surface of the polymeric substrate. Portions of the material layer define a nozzle bore. The nozzle bore is in fluid communication with the liquid chamber. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]     In the detailed description of the preferred embodiments of the invention presented below, reference is made to the accompanying drawings, in which:  
         [0009]      FIG. 1  is a schematic view of first and second example embodiments of the invention;  
         [0010]      FIG. 2  is a schematic view describing an embodiment of the manufacturing process associated with the formation of the first example embodiment of the invention;  
         [0011]      FIG. 3  is a schematic view describing an embodiment of the manufacturing process associated with the formation of the second example embodiment of the invention;  
         [0012]      FIG. 4A  is a schematic view describing an embodiment of the manufacturing process associated with the formation of a third example embodiment of the invention;  
         [0013]      FIG. 4B  is a schematic view describing an embodiment of the manufacturing process associated with the formation of a fourth example embodiment of the invention;  
         [0014]      FIG. 4C  is a schematic view describing an embodiment of the manufacturing process associated with the formation of a fifth example embodiment of the invention;  
         [0015]      FIG. 5  is a schematic view describing another embodiment of the manufacturing process associated with the formation of the example embodiments of the invention;  
         [0016]      FIG. 6A  is a schematic view describing another embodiment of the manufacturing process associated with the formation of the example embodiments of the invention;  
         [0017]      FIG. 6B  is a schematic view describing another embodiment of the manufacturing process associated with the formation of the example embodiments of the invention;  
         [0018]      FIG. 7A  is a schematic view describing another embodiment of the manufacturing process associated with the formation of the example embodiments of the invention; and  
         [0019]      FIG. 7B  is a schematic view describing another embodiment of the manufacturing process associated with the formation of the example embodiments of the invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0020]     The present description will be directed in particular to elements forming part of, or cooperating more directly with, apparatus in accordance with the present invention. It is to be understood that elements not specifically shown or described may take various forms well known to those skilled in the art. In the following description, identical reference numerals have been used, where possible, to designate identical elements.  
         [0021]     Although the term printhead is used herein, it is recognized that printheads are being used today to eject other types of fluids and not just ink. For example, the ejection of various fluids such as medicines, inks, pigments, dyes, conductive and semi-conductive organics, metal particles, and other materials is possible today using a printhead. As such, the term printhead is not intended to be limited to just devices that eject ink.  
         [0022]     Referring to  FIG. 1 , first and second example embodiments of the invention are shown. A printhead  10  includes a liquid chamber  12  made from a polymeric substrate  14 . A nozzle bore(s)  16  made from another material  18  is in fluid communication with the liquid chamber  12 . While shown as a single layer in  FIG. 1  (and  FIGS. 2 through 7 B), material  18  (and/or  18   a  and/or  18   b ) can include a plurality of material layers with each layer being made from the same material or different types of materials. Additionally, when material layers  18   a  and  18   b  are used, each material layer  18   a  and  18   b  can include a plurality of material layers with each layer being made from the same material or different types of materials.  
         [0023]     Optionally, the printhead  10  can include a liquid, for example, ink, channel  20  made from material  18  or another material  22  having properties similar to that of material  18 . Liquid channel  20  is in fluid communication with liquid chamber  12 . Liquid chamber  12 , nozzle bore  16 , and, optionally, liquid channel  20  form a nozzle plate  28  of printhead  10 . Material  22  can also include a plurality of material layers, with each layer being made from the same material or different types of materials.  
         [0024]     Printhead  10  also includes a manifold  24 . Manifold  24  can include a liquid channel(s) like liquid channel  20  and/or a drop forming mechanism(s)  26  associated with one or more liquid chambers  12 , as is known in the art. Drop forming mechanism  26  can be a heater, piezoelectric actuator, etc. Alternatively or additionally, drop forming mechanism(s)  26 , for example, one or a plurality of heaters, can be included in material  18  (and/or  18   a  and/or  18   b ) as described in, for example, U.S. Pat. No. 6,412,928 B1, issued Jul. 2, 2002, to Anagnostopoulos et al.; U.S. Pat. No. 6,450,619 B1, issued Sep. 17, 2002, to Anagnostopoulos et al.; and U.S. Pat. No. 6,491,376 B2, issued Dec. 10, 2002, to Trauernicht et al. When this occurs, drop forming mechanism(s)  26  is typically positioned about nozzle bore(s)  16 . Regardless of where drop forming mechanism(s)  26  is located, drop forming mechanism(s)  26  is operable to form liquid drops from liquid located in liquid chamber  12  in either a continuous or drop on demand manner as is known in the art.  
         [0025]     Material  18  is commonly referred to as a hard coat bore material, for example, silicon nitride, silicon oxynitride, silicon oxide, poly(siloxanes), poly(silanes), or poly(benzocyclobutene) (BCB). Nozzle bore(s)  16  are formed in material  18 . As such, material  18  helps to define nozzle bore  16  in that nozzle bore  16  is formed from a different material and in a different material layer when compared to other features, for example, liquid chamber  12 , or material layers, for example, polymeric substrate  14 , of printhead  10 . Typically, material  18  is harder than the other materials that make up printhead  10 . However, material  18  can be selected such that it is just as hard or slightly less hard than the other materials that make up printhead  10 . The etch rate of material  18  is at least equal to or slower than that of polymeric substrate  14  for the etchant chemistry used in preferred example embodiments of the invention. Typically, material  18  is also thicker than the material(s), for example, metal materials, used to form nozzle bores described in the prior art. However, material  18  is thinner than the polymeric substrate  14  in preferred example embodiments of the invention.  
         [0026]     The first example embodiment of the invention does not include liquid channel  20  and is described in more detail with reference to  FIG. 2 . In this embodiment, manifold  24  may or may not include one or more liquid channels so that liquid chamber(s)  12  can be refilled after fluid is ejected through nozzle bore  16  using drop forming mechanism  26 .  
         [0027]     The second example embodiment of the invention includes liquid channel  20  and is described in more detail with reference to  FIG. 3 . In this embodiment, manifold  24  may or may not include one more liquid channels so that liquid chamber(s)  12  can be refilled after fluid is ejected through nozzle bore  16  using drop forming mechanism  26 .  
         [0028]     Referring to  FIG. 2 , the formation of nozzle plate  28  of the first example embodiment of the invention is shown. After completion of the fabrication process, nozzle plate  28  is attached to manifold  24  using conventional processes known in the art.  
         [0029]     This process begins with polymeric material substrate  14 . Another substrate  32 , made from, for example, glass or silicon, is laminated to one surface of polymeric substrate  14 . A liquid chamber mask  34  is applied to substrate  32  either before or after substrate  32  is laminated to polymeric substrate  14 . Optionally, the substrate  32  is patterned using mask  34  prior to lamination of polymeric substrate  14 . Alternatively, substrate  32  can be patterned using maskless methods known in the art prior to lamination of polymeric substrate  14 .  
         [0030]     Material  18  is deposited on another surface of polymeric substrate  14 . Liquid chamber  12  is formed by etching through substrate  32 , the laminate  36 , and at least some of polymeric substrate  14  using liquid chamber mask  34  as a guide. When substrate  32  is patterned prior to lamination of polymer substrate  14 , then liquid chamber  12  can be formed by etching the laminate  36 , and at least some of polymeric substrate  14  using substrate  32  as a guide.  
         [0031]     A bore mask  38 , for example, a photoresist or a thin metal layer, is applied to a surface of material  18  not contacting polymeric substrate  14 . Nozzle bore  16  is formed by etching through material  18  using bore mask  38  as a guide, and, optionally, at least some of polymeric substrate  14  when at least some of the polymeric substrate  14  remains from the etching step described in the preceding paragraph. Bore mask  38  can be removed either during the etching process (when the etchant is selected such that it removes the bore mask  38  while removing material  18 ) or after etching is complete using conventional means. Alternatively, bore mask  38  can remain on the surface of material  18 . When etching is complete, polymeric substrate  14  is delaminated from substrate  32  forming nozzle plate  28 . Alternatively, polymeric substrate  14  can remain laminated to substrate  32  forming nozzle plate  28 .  
         [0032]     Referring to  FIG. 3 , the formation of nozzle plate  28  of the second example embodiment of the invention is shown. After completion of the fabrication process, nozzle plate  28  is attached to manifold  24  using conventional processes known in the art.  
         [0033]     This process begins with a first material layer  18   a  being deposited on one surface of polymeric material substrate  14  and then flipped so that a surface of first material layer  18   a  not contacting polymeric substrate  14  can be laminated to substrate  32 . This process is described in more detail with reference to  FIGS. 5, 6 , or  7 .  
         [0034]     A liquid chamber mask  34  can be applied to substrate  32  either before or after substrate  32  is laminated to first material layer  18   a.  Optionally, the substrate  32  is patterned using mask  34  prior to lamination of polymeric substrate  14 . Alternatively, substrate  32  can be patterned using maskless methods known in the art prior to lamination of polymeric substrate  14 . After first material layer  18   a  is laminated to substrate  32 , a second material layer  18   b  is deposited to the other surface of polymeric substrate  14 . Liquid chamber  12  is formed by first etching through substrate  32 , the laminate  36 , and the first material layer  18   a , and then etching at least some of polymeric substrate  14  using liquid chamber mask  34  as a guide. When substrate  32  is patterned prior to lamination of polymer substrate  14 , then liquid chamber  12  can be formed by etching the laminate  36 , first material layer  18   a,  and at least some of polymeric substrate  14  using substrate  32  as a guide.  
         [0035]     A bore mask  38 , for example, a photoresist or a thin metal layer, is applied to a surface of the second material layer  18   b  not contacting polymeric substrate  14 . Nozzle bore  16  is formed by etching through second material layer  18   b  using bore mask  38  as a guide, and optionally, at least some of polymer substrate  14  when at least some of the polymeric substrate  14  remains from the etching step described in the preceding paragraph. Bore mask  38  can be removed either during the etching process (when the etchant is selected such that it removes the bore mask  38  while removing material  18   b ) or after etching is complete using conventional means. Alternatively, bore mask  38  can remain on the surface of material  18 . When etching is complete, first material layer  18   a  is delaminated from substrate  32  forming nozzle plate  28 . Alternatively, material layer  18   a  can remain laminated to substrate  32  forming nozzle plate  28 .  
         [0036]     Referring to  FIG. 4A , formation of a nozzle plate  28  having a larger liquidliquid chamber  12 , as compared to the liquid chambers described above, in fluid communication with a plurality of nozzle bores  16  is possible using the fabrication process of the invention.  
         [0037]     This process begins with polymeric material substrate  14 . Another substrate  32 , made from, for example, glass or silicon is laminated to one surface of polymeric substrate  14 . A liquid chamber mask  34  is applied to substrate  32  either before or after substrate  32  is laminated to polymeric substrate  14 . Optionally, the substrate  32  is patterned using mask  34  prior to lamination of polymeric substrate  14 . Alternatively, substrate  32  can be patterned using maskless methods known in the art prior to lamination of polymeric substrate  14 . Mask  34  defines liquid chambers that are larger than the liquid chambers defined by mask  34  described above with reference to FIGS.  2  or  3 .  
         [0038]     Material  18  is deposited on another surface of polymeric substrate  14 . Liquid chamber  12  is formed by etching through substrate  32 , the laminate  36 , and at least some of polymeric substrate  14  using liquid chamber mask  34  as a guide. When substrate  32  is patterned prior to lamination of polymer substrate  14 , then liquid chamber  12  can be formed by etching the laminate  36 , and at least some of polymeric substrate  14  using substrate  32  as a guide.  
         [0039]     A bore mask  38 , for example, a photoresist or a thin metal layer, is applied to a surface of material layer  18  not contacting polymeric substrate  14 . Nozzle bore  16  is formed by etching through material layer  18  using bore mask  38  as a guide, and optionally, at least some of polymer substrate  14  when at least some of the polymeric substrate  14  remains from the etching step described in the preceding paragraph. Bore mask  38  can be removed either during the etching process (when the etchant is selected such that it removes the bore mask  38  while removing material  18 ) or after etching is complete using conventional means. Alternatively, bore mask  38  can remain on the surface of material  18 . When etching is complete, polymeric substrate  14  is delaminated from substrate  32  forming nozzle plate  28 . Alternatively, polymeric substrate  14  can remain laminated to substrate  32  forming nozzle plate  28 .  
         [0040]     Referring to  FIG. 4B , material  18  can be deposited on both sides of polymeric substrate  14  using a process like one of those described with reference to  FIGS. 3, 5 ,  6 , or  7 . When this is done, the process begins with polymeric substrate  14  being laminated to substrate  32  using a laminate  36 . A first material layer  18   a  is deposited on a surface of polymeric substrate  14  not laminated to substrate  32 . First material layer  18   a  and polymeric substrate  14  are delaminated from substrate  32  and flipped so that a surface of first material layer  18   a  not contacting polymeric substrate  14  can be laminated to substrate  32  using laminate  36 . A second material layer  18   b  is deposited to the surface of polymeric substrate  14  not contacting first material layer  18   a.    
         [0041]     A liquid chamber mask  34  can be applied to substrate  32  either before or after substrate  32  is laminated to first material layer  18   a.  Optionally, the substrate  32  is patterned using mask  34  prior to lamination of polymeric substrate  14 . Alternatively, substrate  32  can be patterned using maskless methods known in the art prior to lamination of polymeric substrate  14 . Liquid chamber  12  is formed by first etching through substrate  32 , the laminate  36 , and the first material layer  18   a,  and then etching at least some of polymeric substrate  14  using liquid chamber mask  34  as a guide. When substrate  32  is patterned prior to lamination of polymer substrate  14 , then liquid chamber  12  can be formed by etching the laminate  36 , first material layer  18   a,  and at least some of polymeric substrate  14  using substrate  32  as a guide.  
         [0042]     A bore mask  38  is applied to a surface of material  18   b  not contacting polymeric substrate  14 . Nozzle bores  16  are formed by etching through material  18   b  and, optionally, at least some of polymeric substrate  14  when at least some of polymeric substrate  14  remains from the etching step described in the preceding paragraph, using bore mask  38  as a guide. Bore mask  38  can be removed either during the etching process (when the etchant is selected such that it removes the bore mask  38  while removing material  18   b ) or after etching is complete using conventional means. Alternatively, bore mask  38  can remain on the surface of material  18 . When etching is complete, first material layer  18   a  is delaminated from substrate  32  forming nozzle plate  28 . Alternatively, material layer  18   a  can remain laminated to substrate  32  forming nozzle plate  28 .  
         [0043]     Referring to  FIG. 4C , material  18  can be deposited on both sides of polymeric substrate  14  using a process like one of those described with reference to  FIGS. 3, 5 ,  6 , or  7 . When this is done, the process begins with polymeric substrate  14  being laminated to substrate  32  using a laminate  36 . A first material layer  18   a  is deposited on a surface of polymeric substrate  14  not laminated to substrate  32 . First material layer  18   a  is patterned with features smaller than those patterned in carrier substrate  32 . First material layer  18   a  and polymeric substrate  14  are delaminated from substrate  32  and flipped so that a surface of first material layer  18   a  not contacting polymeric substrate  14  can be laminated to substrate  32  using laminate  36 . A second material layer  18   b  is deposited to the surface of polymeric substrate  14  not contacting first material layer  18   a.    
         [0044]     A liquid chamber mask  34  can be applied to substrate  32  either before or after substrate  32  is laminated to first material layer  18   a.  Optionally, the substrate  32  is patterned using mask  34  or other maskless methods known in the art prior to lamination of polymeric substrate  14 . Liquid chamber  12  is formed by first etching through substrate  32 , the laminate  36 , and at least some of polymeric substrate  14  using first material layer  18   a  as a guide. When substrate  32  is patterned prior to lamination of polymer substrate  14 , then liquid chamber  12  can be formed by etching the laminate  36 , and at least some of polymeric substrate  14  using first material layer  18   a  as a guide.  
         [0045]     A bore mask  38  is applied to a surface of material  18   b  not contacting polymeric substrate  14 . Nozzle bores  16  are formed by etching through material  18   b  and, optionally, at least some of polymeric substrate  14  when at least some of polymeric substrate  14  remains from the etching step described in the preceding paragraph, using bore mask  38  as a guide. Bore mask  38  can be removed either during the etching process (when the etchant is selected such that it removes the bore mask  38  while removing material  18   b ) or after etching is complete using conventional means. Alternatively, bore mask  38  can remain on the surface of material  18 . When etching is complete, first material layer  18   a  is delaminated from substrate  32  forming nozzle plate  28 . Alternatively, material layer  18   a  can remain laminated to substrate  32  forming nozzle plate  28 .  
         [0046]     Liquid chamber  12  of the example embodiments of the invention can also be formed using etching processes commonly referred to as a backside etch (non-nozzle bore side), a front side etch (nozzle bore side), or a partial etch of both sides. The backside etch process of polymeric substrate  14  is described in more detail with reference to  FIG. 5 . The partial etch of both sides of polymeric substrate  14  is described in more detail with reference to  FIGS. 6A and 6B . The front side etch process of polymeric substrate  14  is described in more detail with reference to  FIGS. 7A and 7B .  
         [0047]     Referring to  FIG. 5 , backside etching of polymeric substrate  14  begins with polymeric substrate  14  being laminated to substrate  32  using a laminate  36 . A first material layer  18   a  is deposited on a surface of polymeric substrate not laminated to substrate  32 . First material layer  18   a  and polymeric substrate  14  are delaminated from substrate  32  and flipped so that a surface of first material layer  18   a  not contacting polymeric substrate  14  can be laminated to substrate  32  using laminate  36 . A second material layer  18   b  is deposited to the surface of polymeric substrate  14  not contacting first material layer  18   a.    
         [0048]     A liquid chamber mask  34  is applied to second material layer  18   b.  Liquid chamber  12  is formed by etching through second material layer  18   b,  and polymeric substrate  14  using at least liquid chamber mask  34  as a guide. Etching second material layer  18   b  forms liquid channel  20 . Material layer  18   b  and, optionally, some of polymeric substrate  14 , can be etched such that liquid channel  20  is in fluid communication with one nozzle bore  16  or a plurality of nozzle bores  16 .  
         [0049]     In some etching processes, mask  34  serves as a mask when etching material layer  18   b,  and then, material layer  18   b  serves as the mask when etching polymeric substrate  14 . Alternatively, mask  34  serves as the mask when etching material layer  18   b  and polymeric substrate  14 .  
         [0050]     Mask  34  can be removed either during the etching process (when the etchant is selected such that it removes mask  34  while removing material  18   b ) or after etching is complete using conventional means. Alternatively, mask  34  can remain on the surface of material  18   b.    
         [0051]     Second material layer  18   b,  polymeric substrate  14 , and first material layer  18   a  are delaminated from substrate  32  and flipped. Second material layer  18   b  is laminated to substrate  32  so that a bore mask  38  can be applied to a surface of first material layer  18   a.  Nozzle bore  16  is formed by etching through first material layer  18   a  using bore mask  38  as a guide. When etching is complete, second material layer  18   b  is delaminated from substrate  32  forming nozzle plate  28 . Bore mask  38  can be removed either during the etching process (when the etchant is selected such that it removes the bore mask  38  while removing material  18   b ) or after etching is complete using conventional means. Alternatively, bore mask  38  can remain on the surface of material  18 .  
         [0052]     Referring to  FIG. 6A , partial etching of both sides of polymeric substrate  14  begins with polymeric substrate  14  being laminated to substrate  32  using a laminate  36 . A first material layer  18   a  is deposited on a surface of polymeric substrate not laminated to substrate  32 . First material layer  18   a  and polymeric substrate  14  are delaminated from substrate  32  and flipped so that a surface of first material layer  18   a  not contacting polymeric substrate  14  can be laminated to substrate  32  using laminate  36 . A second material layer  18   b  is deposited to the surface of polymeric substrate  14  not contacting first material layer  18   a.    
         [0053]     A liquid chamber mask  34  is applied to second material layer  18   b.  Liquid chamber  12  is formed by etching through second material layer  18   b,  and partially etching polymeric substrate  14  using at least liquid chamber mask  34  as a guide. Etching second material layer  18   b  forms liquid channel  20 . Material layer  18   b  and, optionally, some of polymeric substrate  14 , can be etched such that liquid channel  20  is in fluid communication with one nozzle bore  16  or a plurality of nozzle bores  16 .  
         [0054]     In some etching processes, mask  34  serves as a mask when etching material layer  18   b,  and then, material layer  18   b  serves as the mask when etching polymeric substrate  14 . Alternatively, mask  34  serves as the mask when etching material layer  18   b  and polymeric substrate  14 .  
         [0055]     Mask  34  can be removed either during the etching process (when the etchant is selected such that it removes mask  34  while removing material  18   b ) or after etching is complete using conventional means. Alternatively, mask  34  can remain on the surface of material  18   b.    
         [0056]     Second material layer  18   b,  polymeric substrate  14 , and first material layer  18   a  are delaminated from substrate  32  and flipped. Second material layer  18   b  is laminated to substrate  32  so that a bore mask  38  can be applied to a surface of first material layer  18   a.  Nozzle bore  16  is formed by etching through first material layer  18   a  and the remaining portion of polymeric substrate  14  using at least bore mask  38  as a guide.  
         [0057]     In some etching processes, mask  38  serves as a mask when etching material layer  18   a,  and then, material layer  18   a  serves as the mask when etching the remaining portion of polymeric substrate  14 . Alternatively, mask  38  serves as the mask when etching material layer  18   a  and the remaining portion of polymeric substrate  14 .  
         [0058]     Mask  38  can be removed either during the etching process (when the etchant is selected such that it removes mask  38  while removing material  18   a ) or after etching is complete using conventional means. Alternatively, mask  38  can remain on the surface of material  18   a.  When etching is complete, second material layer  18   b  is delaminated from substrate  32  forming nozzle plate  28 .  
         [0059]     Referring to  FIG. 6B , partial etching of both sides of polymeric substrate  14  begins with polymeric substrate  14  being laminated to substrate  32  using a laminate  36 . A first material layer  18   a  is deposited on a surface of polymeric substrate not laminated to substrate  32 .  
         [0060]     A liquid chamber mask  34  is applied to first material layer  18   a.  Liquid chamber  12  is formed by etching through first material layer  18   a,  and partially etching polymeric substrate  14  using at least liquid chamber mask  34  as a guide. Etching first material layer  18   a  forms liquid channel  20 . Material layer  18   a  and, optionally, some of polymeric substrate  14 , can be etched such that liquid channel  20  is in fluid communication with one nozzle bore  16  or a plurality of nozzle bores  16 .  
         [0061]     In some etching processes, mask  34  serves as a mask when etching material layer  18   a,  and then, material layer  18   a  serves as the mask when etching polymeric substrate  14 . Alternatively, mask  34  serves as the mask when etching material layer  18   a  and polymeric substrate  14 . Mask  34  can be removed either during the etching process (when the etchant is selected such that it removes mask  34  while removing material  18   a ) or after etching is complete using conventional means. Alternatively, mask  34  can remain on the surface of material  18   a.    
         [0062]     First material layer  18   a  and polymeric substrate  14  are delaminated from substrate  32  and flipped so that a surface of first material layer  18   a  not contacting polymeric substrate  14  can be laminated to substrate  32  using laminate  36 . A second material layer  18   b  is deposited to the surface of polymeric substrate  14  not contacting first material layer  18   a.    
         [0063]     Bore mask  38  can be applied to a surface of second material layer  18   b.  Nozzle bore  16  is formed by etching through first material layer  18   b  and the remaining portion of polymeric substrate  14  using at least bore mask  38  as a guide.  
         [0064]     In some etching processes, mask  38  serves as a mask when etching material layer  18   b,  and then, material layer  18   b  serves as the mask when etching the remaining portion of polymeric substrate  14 . Alternatively, mask  38  serves as the mask when etching material layer  18   b  and the remaining portion of polymeric substrate  14 . Mask  38  can be removed either during the etching process (when the etchant is selected such that it removes mask  38  while removing material  18   b ) or after etching is complete using conventional means. Alternatively, mask  38  can remain on the surface of material  18   b.  When etching is complete, first material layer  18   a  is delaminated from substrate  32  forming nozzle plate  28 .  
         [0065]     Referring to  FIG. 7A , front side etching of polymeric substrate  14  begins with polymeric substrate  14  being laminated to substrate  32  using a laminate  36 . A first material layer  18   a  is deposited on a surface of polymeric substrate not laminated to substrate  32 . First material layer  18   a  and polymeric substrate  14  are delaminated from substrate  32  and flipped so that a surface of first material layer  18   a  not contacting polymeric substrate  14  can be laminated to substrate  32  using laminate  36 . A second material layer  18   b  is deposited to the surface of polymeric substrate  14  not contacting first material layer  18   a.    
         [0066]     A nozzle bore/liquid chamber mask  40  is applied to second material layer  18   b.  Nozzle bore  16  is formed by etching through second material layer  18   b  using at least bore/chamber mask  40  as a guide. Liquid chamber  12  can be partially formed by partially etching polymeric material substrate  14  or completely formed by fully etching polymeric material substrate  14  using at least bore/chamber mask  40  as a guide.  
         [0067]     In some etching processes, mask  40  serves as a mask when etching material layer  18   b,  and then, material layer  18   b  serves as the mask when etching polymeric substrate  14 . Alternatively, mask  40  serves as the mask when etching material layer  18   b  and polymeric substrate  14 .  
         [0068]     Mask  40  can be removed either during the etching process (when the etchant is selected such that it removes mask  40  while removing material  18   b ) or after etching is complete using conventional means. Alternatively, mask  40  can remain on the surface of material  18   b.    
         [0069]     Second material layer  18   b,  polymeric substrate  14 , and first material layer  18   a  are delaminated from substrate  32  and flipped. Second material layer  18   b  is laminated to substrate  32  so that a channel mask  42  can be applied to a surface of first material layer  18   a.  A liquid channel  20  is formed by etching first material layer  18   a  using at least channel mask  42  as a guide. Material layer  18   a  can be etched such that liquid channel  20  is in fluid communication with one nozzle bore  16  or a plurality of nozzle bores  16 . The formation of liquid chamber  12  can optionally be finished by partially etching the remaining polymeric material substrate  14  or completed by fully etching polymeric material substrate  14  using at least bore/chamber mask  42  as a guide.  
         [0070]     In some etching processes, mask  42  serves as a mask when etching material layer  18   a,  and then, material layer  18   a  serves as the mask when etching polymeric substrate  14 . Alternatively, mask  42  serves as the mask when etching material layer  18   a  and polymeric substrate  14 .  
         [0071]     Mask  42  can be removed either during the etching process (when the etchant is selected such that it removes mask  42  while removing material  18   a ) or after etching is complete using conventional means. Alternatively, mask  42  can remain on the surface of material  18   a.  When etching is complete, second material layer  18   b  is delaminated from substrate  32  forming nozzle plate  28 .  
         [0072]     Referring to  FIG. 7B , front side etching of polymeric substrate  14  begins with polymeric substrate  14  being laminated to substrate  32  using a laminate  36 . A material layer  18  is deposited on a surface of polymeric substrate not laminated to substrate  32 .  
         [0073]     A nozzle bore/liquid chamber mask  40  is applied to material layer  18 . Nozzle bore  16  is formed by etching through material layer  18  using at least bore/chamber mask  40  as a guide. Liquid chamber  12  can be formed by fully etching polymeric material substrate  14  using at least bore/chamber mask  40  as a guide.  
         [0074]     In some etching processes, mask  40  serves as a mask when etching material layer  18 , and then, material layer  18  serves as the mask when etching polymeric substrate  14 . Alternatively, mask  40  serves as the mask when etching material layer  18  and polymeric substrate  14 .  
         [0075]     Mask  40  can be removed either during the etching process (when the etchant is selected such that it removes mask  40  while removing material  18 ) or after etching is complete using conventional means. Alternatively, mask  40  can remain on the surface of material  18 . When etching is complete, polymer substrate  14  is delaminated from substrate  32  forming nozzle plate  28 .  
         [0076]     Referring back to  FIGS. 1-7 , fabrication process steps which describe etching preferably use a dry or vacuum-based etching process or processes because dry etching creates an anisotropic or uni-directional etch which help facilitate high-fidelity pattern transfer. The example embodiments of the invention used a reactive ion etching (RIE) etching process, for example, an RIE oxygen plasma etching process. This process is, typically, more amenable to microelectronic fabrication processes and allows tight control (particularly in the plane of the substrate) of the alignment of the features formed when compared to other types of fabrication processes. For example, a plasma of at least oxygen gas can be used to etch polymer substrate  14  and/or material  18 ,  18   a,  and/or  18   b  when material  18 ,  18   a,  and/or  18   b  is a poly(siloxanes), poly(silanes), polyimide, or poly(benzocyclobutenes). However, other types of etching processes, including other chemistries, can be used. For example, fluorine-based chemistries can be used to etch material  18 ,  18   a,  and/or  18   b  when material  18 ,  18   a,  and/or  18   b  is a silicon nitride or a silicon oxide. Fluorine chemistries can also be used to enhance etching polymer substrate  14  and/or material  18 ,  18   a  and/or  18   b  when  18 .  18 A and/or  18   b  is a poly(siloxane), polyimide, poly(silane) or poly(benzocyclobutene).  
         [0077]     In addition to silicon nitride, material  18 ,  18   a,  and/or  18   b  can be an inorganic film, a glass, and/or other types of silicon compounds, for example, silicon oxide, silicon oxynitride, silicon carbide, aluminum oxide, or an organic film, such as those based on poly(siloxane), polysilane, polyimide, or poly(benzocyclobutene). Material  18 ,  18   a,  and/or  18   b  can be a single layer of material, or a multi-layered stack of the same or different materials. Typically, material  18 ,  18   a,  and/or  18   b  is 0.5-10 microns thick, preferably 1-6 microns thick, and more preferably 2-4 microns thick.  
         [0078]     Polymeric substrate  14  can be made from material including, for example, polyesters such as poly(ethylene naphthalate) and poly(ethyelene teraphthalate), and polymers based on poly(ether sulfones), poly(norbornenes), poly(carbonates), poly(cyclo-olefins), poly(acrylates) and polyimides. Typically, the polymeric substrate is 25-300 microns thick, preferably 50-200 microns thick, and more preferably 75-125 microns thick.  
         [0079]     Deposition of material  18 ,  18   a,  and/or  18   b  can include any type of deposition process known in the art. For example, deposition of material  18 ,  18   a,  and/or  18   b  can be accomplished by sputter deposition, e-beam deposition, thermal evaporation, chemical vapor deposition, or spin-coating.  
         [0080]     Fabrication process steps which describe lamination or delamination can include any type of lamination or delamination processes known in the art. For example, lamination can be accomplished using hot lamination processes, cold lamination processes, lamination processes using a nip roller, lamination processes using a pressure diaphragm, or lamination processes conducted under vacuum. Selection of the appropriate laminate depends on the lamination process. For example, laminates can include ultraviolet light curable adhesives, thermally curable adhesives, or pressure sensitive adhesives known in the art. Some examples of adhesives include elastomeric adhesives such as those manufactured by Gel-Pak, a division of Delphon Industries, Hayward, CA; and thermal release tapes such as those manufactured by Nitto Denko Corporation, Osaka, Japan. Delamination can be accomplished using, for example, thermally induced delamination, delamination induced by ultraviolet light, pressure induced delamination, solvent-induced delamination, or delamination induced by dry etching.  
         [0081]     Alternatively, lamination can be accomplished by treating the surfaces of the items to be laminated such that a bond is formed when the items contact each other that is strong enough to adhere the surfaces of the items together. Examples of these types of surface treatments include, but are not limited to, oxygen or nitrogen plasma treatment, ozone treatment, and thin monolayers of cross-linkable molecules.  
         [0082]     The fabrication processes described above find application when forming devices incorporating fluid chambers and/or passageways in polymeric substrates. These devices include, for example, printheads of the type commonly referred to a page wide printheads, see, for example, U.S. Pat. No. 6,663,221 B2, issued Dec. 16, 2003, to Anagnostopoulos et. In a page wide printhead, the length of the printhead is preferably at least equal to the width of the receiver. However, the length of the page wide printhead is scalable depending on the specific application contemplated and, as such, can range from less than one inch to lengths exceeding twenty four inches.  
         [0083]     The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the scope of the invention.