TW201828358A - Methods of etching conductive features, and related devices and systems - Google Patents

Abstract

A method of making a device patterned with one or more electrically conductive features includes depositing a conductive material layer over an electrically insulating surface of a substrate, depositing an anti-corrosive material layer over the conductive material layer, and depositing an etch-resist material layer over the anti-corrosive material layer. The etch-resist material layer may be deposited over the anti-corrosive material layer, and the anti-corrosive material layer forming a bi-component etch mask in a pattern resulting in covered portions of the conductive material layer and exposed portions of the conductive material layer, the covered portions being positioned at locations corresponding to one or more conductive features of the device. A wet-etch process is performed to remove the exposed portions of the conductive material layer from the electrically insulating substrate, and the bi-component etch mask is removed to expose the remaining conductive material. Systems and devices relate to devices with patterned features.

Description

 Method for etching conductive features and related devices and systems    [Cross-reference to related applications]  

The present application claims the following U.S. Provisional Application Serial No. 62/432,710, filed on Dec.

 【Introduction】  

The manufacture of various electronic devices and electronic components requires the fabrication of a patterned layer on the substrate. For example, microchips, printed circuit boards, solar cells, electronic displays (such as liquid crystal displays, organic light emitting diode displays, and quantum dot electroluminescent displays), and various other electrical or optical devices and components can be borrowed from substrates. Consisting of a plurality of overlapping patterned layers of different materials supported. Fabricating one such patterned layer on the substrate can be performed by applying a layer of unpatterned material to the substrate, preparing a resist mask on the layer, and performing an etching process to remove the layer from the resist mask. The covered portion is thus formed by forming a patterned layer on the substrate.

In one illustrative example that may be used to fabricate, for example, a printed circuit board (PCB) or other electronic component, a layer of conductive metal is applied to the electrically insulating surface of the substrate (or, equivalently, a conductive layer is formed on the electrically insulating surface of the substrate) Applying a resist mask to (or formed on) the conductive layer, and performing an etching process to remove a portion of the conductive layer that is not covered by the resist mask, thereby forming patterned conductive on the electrically insulating surface of the substrate Floor. The patterned conductive layer thus formed can include one or more conductive features of the conductive material on the electrically insulating surface of the substrate, which further comprise, for example, lines, circles, squares, and other shapes. In some cases, the etching process used to form such a patterned conductive layer can be a wet etch process whereby the liquid etch material interacts with the conductive layer to remove the conductive layer from the electrically insulating surface of the substrate. For example, such a wet etch process can be a wet "chemical" etch process.

A common feature of wet etching is "undercut", which in the representative example of etching a conductive layer refers to the removal of the material of the conductive layer under the etch mask. Such undercuts can reduce the conductivity of the conductive layer by reducing the width of the feature perpendicular to the direction of current flow relative to the corresponding width of the etched mask. As a result, the conductivity may fall below the desired level. Such a decrease in conductivity due to undercut can be particularly pronounced with relatively small feature widths, such as feature widths below about 60 [mu]m. This undercut image can also impart a "sidewall" that is either oblique or non-planar to the conductive features. As used herein, "sidewall" refers to a side surface of a feature, such as a wall on a feature side that extends downwardly from the top of the feature near the etched mask to the bottom of the feature near the substrate. In some cases, features associated with such undercuts may have sloped or non-planar sidewalls such that the width near the top of the feature (near the etch mask) is less than the width of the feature bottom (near the substrate). Since the particular minimum feature width at the top of the feature can be desired, such as to achieve the desired conductivity or achieve the desired electrical frequency response, such undercut can be at least a minimum feature width or a minimum feature to feature spacing. One imposes a lower limit, thereby limiting the feature density that can be provided on the substrate.

For applications other than the patterning of conductive metal lines in PCBs, undercuts may be undesirable. For example, similar considerations for PCBs as described above are also applicable to other applications that utilize metal wires to carry current and/or electrical signals, for example, in the fabrication of microchips, electronic displays, or solar cells. In another example, other considerations can be applied to applications that utilize non-metallic patterned layers (eg, optical coatings or insulating layers) in the fabrication of electronic or optical devices or components, where substantially vertical sidewalls are desired of.

When forming a patterned layer on a substrate for fabricating electronic and/or optical devices or electronic and/or optical components, there are improved techniques for mitigating (eg, reducing or eliminating) undercuts on features formed using wet etch procedures Need.

In conventional processes, the etch mask described above is formed by applying a blanket coating of a light sensitive material (typically a UV light sensitive material) to the substrate, the light sensitive material being converted to an etch after patterning exposure and subsequent processing. Mask. Such subsequent processing typically includes removal of the light sensitive material (eg, during the development step) to form an etched mask pattern on the substrate. In many cases, such as, but not limited to, when an etch mask is used to pattern a metal layer of a PCB, the etch mask covers less than 50% of the surface of the substrate, and the removed light sensitive material is discarded as a waste. In many cases, the removal of the photosensitive material requires cleaning the substrate in a liquid such as a developer, and the liquid used to perform such cleaning is discarded as a waste. In many cases, such as, but not limited to, when an etch mask is used to pattern a metal layer of a PCB, the light sensitive material is prepared on a carrier sheet and then transferred from the carrier sheet to the substrate via lamination, and in such The carrier sheet was discarded as waste after transfer. In the manufacture of electronic and/or optical devices and/or components, it is often desirable to reduce waste. One way to reduce such waste is to apply an etch mask directly to the substrate in a desired pattern using a pressureless printing (eg, inkjet printing) to deliver the liquid etched mask ink to the substrate in a desired pattern, and then The liquid coating is subsequently processed (eg, via drying and/or baking) to form a finished etch mask. However, inks delivered by such pressureless printing methods are generally not well adsorbed on the surface of substrates used in the manufacture of optical and/or electrical components and/or devices, and such inks may be on such substrates. Spread and/or shift in an uncontrolled manner, causing phenomena such as aggregation, coalescence, and dot gain. Therefore, the etch mask obtained by such a pressureless printing method can exhibit reduced resolution, lack of detail, inconsistent pattern line width, poor line edge smoothness, connections between features to be separated, and continuous An interruption in the feature.

In the case of preparing an etch mask using pressureless printing as described above, there is such an uncontrolled diffusion and/or shifting of (eg, reducing or eliminating) the deposited liquid etch mask ink on the substrate surface. Demand.

In an illustrative aspect of the invention, a method of fabricating a device for patterning one or more conductive features includes depositing a layer of conductive material over an electrically insulating surface of a substrate, depositing a corrosion resistant material over the layer of conductive material a layer, and a layer of resist material deposited over the layer of corrosion resistant material. Depositing a resist material layer over the anti-corrosive material layer, the resist material layer and the anti-corrosion material layer are patterned to form a two-component etch mask to obtain a covered portion of the conductive material layer and the conductive material An exposed portion of the layer disposed at a location corresponding to one or more conductive features of the device. Performing a wet etching process to remove exposed portions of the electrically insulating substrate, and removing the two-component etch mask to expose remaining conductive material of the covered portion of the layer of conductive material to form one or more of the devices Conductive features.

In another illustrative aspect of the invention, an apparatus for fabricating a device having patterned features includes a first deposition module configured to deposit over a layer of electrically conductive material over an electrically insulating surface of the substrate a layer of corrosion resistant material; a second deposition module configured to deposit a layer of resist material over the corrosion resistant material; and a wet etch module configured to etch the layer of conductive material of the substrate.

In still another exemplary aspect of the invention, an apparatus for patterning conductive features includes a substrate having an electrically insulating surface and electrically conductive features disposed on the electrically insulating surface. The conductive feature comprises a height (c) measured in a direction perpendicular to the electrically insulating surface; a first width (a) measured at the electrically insulating surface; and a height (c) along the electrically conductive feature, and The electrically insulating surface is opposite the second width (b) measured at the end of the electrically conductive feature. The half of the difference between the first width (a) and the second width (b) divided by the height (c) has a value of at least 2 (ie, [ab]/c 2).

In still another exemplary aspect of the invention, a method includes applying a first liquid composition comprising a first reactive component to a metallic surface to form a primer layer, and at the bottom by a pressureless printing method A second liquid composition comprising a second reactive component is imagewise printed on the lacquer layer to produce an etch mask in accordance with a predetermined pattern. When the droplets of the second liquid composition contact the primer layer, the second reactive component chemically reacts with the first reactive component to stop the droplets from moving.

The other objects, features, and/or advantages of the invention are set forth in the description which follows. At least some of these objects and advantages can be realized and obtained by the elements and combinations particularly pointed out in the appended claims.

The above general description and the following detailed description are intended to be illustrative and not restrictive.

 【Detailed description】  

In the following detailed description, numerous specific details are set forth However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well known methods, procedures, and components have not been described in detail in order to avoid obscuring the invention.

Microchips, printed circuit boards, solar cells, electronic displays such as, but not limited to, liquid crystal displays, organic light emitting diode displays, and quantum dot electroluminescent displays, and various other electrical or optical devices and components may be It consists of a plurality of overlapping layers of different materials supported by the substrate, including patterned layers. Various illustrative embodiments of the invention contemplate methods and apparatus for forming a patterned layer on a substrate for use in electrical and/or optical devices and/or components. As used herein, "device layer" shall mean a material in its final form, which may be patterned in some cases, contained in a finished optical and/or electronic device and/or component. Further, the "patterned device layer" should refer to such a layer after being patterned, and the "unpatterned device layer" means before being patterned. Such a layer. For example, various illustrative embodiments contemplate a patterning device layer of a conductive material comprising a set of conductive lines, for example, as fabricated on a substrate as part of manufacturing a printed circuit board (PCB) or other electronic component. In accordance with a specific embodiment of the invention, an unpatterned device layer on the substrate (such as, but not limited to, a conductive layer of copper or other conductive material overlying the electrically insulating surface of the substrate) may be coated with "undercut reduction" -reducing) A "primer" layer of material having an effect of reducing undercut during a wet etch process for removing device layer material exposed by the etch mask. For example, the undercut reducing material can be a corrosion resistant material that can include materials that exhibit corrosion resistance properties relative to the device layer material. Such a corrosion-resistant material may comprise a polymer, an organic material, an inorganic material, a Schiff bases, or other materials, such as disclosed in International Patent Application Publication No. WO 2016/193978 A2 and WO 2016/025949 A1, each of which The entire contents of one are incorporated herein by reference. The corrosion resistant material may be blanket formed or blanket deposited, or patterned or patterned over the unpatterned device layer. In various exemplary embodiments, the term anti-corrosive material and undercut reducing material are used interchangeably.

Various exemplary embodiments of the present invention contemplate forming a primer layer comprising an undercut reducing material over a layer of unpatterned device on a substrate, and then forming a patterned layer of resist material over the primer layer An etch mask is formed on the substrate. Other illustrative embodiments of the present invention contemplate an unpatterned device layer on a substrate by forming a patterned layer of a mixture of undercut reducing material and resist material over the substrate over the unpatterned device layer. An etch mask is formed over the top without the need to form a separate layer comprising an undercut reducing material, such as a primer layer. In an exemplary embodiment, a primer layer comprising an undercut reducing material is formed over the unpatterned device layer on the substrate, and then the liquid resist ink is applied or deposited in a pattern on the primer layer, and then via Subsequent processing (eg, by drying or baking the ink to form a solid patterned layer of resist material) to convert the liquid ink into an etch mask to form an etch mask over the primer layer, wherein such a liquid resist The ink can comprise a material that interacts with the primer layer. For example, a liquid resist ink can undergo a chemical reaction upon contact with a primer layer that limits displacement or diffusion of the ink on the surface of the primer, such as via a chemical reaction. In another example, the liquid resist ink can be applied to the surface in the form of droplets delivered by an inkjet nozzle, and such droplets can effectively be immobilized soon or when in contact with the surface of the primer. "Freezing" in place, such that the further displacement or diffusion of the ink droplets on the surface of the primer is greatly reduced or completely stopped, as described in International Publication Nos. WO 2016/193978 A2 and WO 2016/025949 A1, the entire contents of each of which is incorporated herein by reference. This is incorporated herein by reference. In an illustrative embodiment, limiting the diffusion of resist ink on the surface of the primer, for example via a chemical reaction from the interaction between the resist ink and the primer layer, may contribute to the mask pattern to be patterned Accurate deposition above the layer.

In an illustrative embodiment, a primer layer is formed over the unpatterned device layer on the substrate, and the liquid resist ink is delivered to the primer layer in a pattern and then via subsequent processing (eg, by drying or The ink is baked to form a solid patterned layer that resists subsequent corrosion. The liquid ink is converted into an etch mask to form an etch mask over the primer layer. In an exemplary embodiment, the primer layer comprises a first reactive component, the liquid resist ink comprises a second reactive component, and when the resist ink is in contact with the primer layer, the first The second reactive component reacts to effectively stop the ink from moving or "freeze" the ink into place, such that further displacement or diffusion of the ink on the surface of the primer is greatly reduced or completely stopped. In an exemplary embodiment, the primer layer comprises a third reactive component, the liquid resist ink comprises a fourth reactive component, and the reaction of the third and fourth reactive components produces an etch masking material It is relatively insoluble in the resist ink and is relatively insoluble in the etching solution used to subsequently etch the unpatterned device layer (wherein the relatively insoluble herein is defined relative to the fourth reactive component). The etch mask material thus formed is referred to herein as a two-component material or a two-component reaction product. In various embodiments, a reactive component that provides a majority of the mass to form a two-component material that forms an etch mask is referred to as an etch-resist component, or equivalently, an etch-resistant component (etching) -resisting component), while another reactive component is referred to as a fixed component, or equivalently, a fixed reactive component or a fixed composition. In an illustrative embodiment, the resist component comprises a plurality of materials. In an illustrative embodiment, the immobilization component comprises a plurality of materials. In an illustrative embodiment, the resist ink is an aqueous ink and the two component material is relatively insoluble in water. In an exemplary embodiment, the etching solution is an acidic etching solution such as, but not limited to, a mixture of copper chloride and hydrogen peroxide. In an illustrative embodiment, one or more of the first component, the second component, the third component, or the fourth component comprise a plurality of materials. In an illustrative embodiment, the first and third components are the same. In an exemplary embodiment, the second and fourth components are the same. In an exemplary embodiment, the reaction to produce the two-component material is the same as the reaction to stop the droplets of the resist ink from moving on the primer layer. In an illustrative embodiment, the primer layer comprises an undercut prevention material. In an exemplary embodiment, the reactive component of the primer (eg, the first or third reactive component described above) comprises an undercut prevention material. In an illustrative embodiment, the reactive component of the resist ink (eg, the second or fourth reactive component described above) comprises an undercut prevention material. In an illustrative embodiment, the resist ink comprises an undercut prevention material.

In an illustrative embodiment, at least one of the primer or resist ink can comprise a multivalent and/or polycationic group and/or a multivalent inorganic cation. In an illustrative embodiment, at least one of the primer or resist ink can comprise a polyanionic group. In an illustrative embodiment, at least one of the primer or resist ink can comprise a reactive anionic component and is water soluble. In an illustrative embodiment, such reactive anionic components can include at least one anionic polymer (in base form) having a pH above 7.0. In an exemplary embodiment, such an anionic polymer may be selected from the group consisting of acrylic resins in the form of their dissolved salts and styrene-acrylic resins (such as, but not limited to, in the form of sodium salts), sulfonic acid resins in the form of their dissolved salts ( For example, but not limited to, the sodium salt form). In an illustrative embodiment, such anionic polymer can be in the ammonium form or in an amine neutralized form. In an exemplary embodiment, such an anionic polymer can be in the form of a polymer emulsion or dispersion. In various embodiments, the reaction to produce the two-component material causes a substantial increase in the viscosity of the resist ink on the primer layer, and substantially such an increase in viscosity results in an immobilization phenomenon. In various embodiments, the resist ink provides a majority of the material quality that forms the two-component material. In various embodiments, the primer provides most of the material quality of the two-component material, and in this case, the primer layer can contain a resist component, and the resist ink can contain an immobilized component. . In various embodiments, a primer layer is formed by providing a liquid primer ink coating over the unpatterned device layer and then subsequently treating the layer to form a primer layer, for example by drying or baking the layer. . In various embodiments, such primer inks are aqueous. In various embodiments, the primer layer has good adhesion to the unpatterned device layer. In various embodiments, a primer is applied over the unpatterned device layer by inkjet printing, spray coating, metering bar coating, roll coating, dip coating, or any other suitable printing or coating method. Floor. In various embodiments, the primer layer can be a uniform (eg, blanket) coating or can be a patterned coating.

In an exemplary embodiment, the primer layer is at least partially formed by applying a surface activating solution over the unpatterned device layer. In an exemplary embodiment, the surface activating solution comprises one or more of a copper salt, an iron salt, a chromic acid-sulfuric acid, a persulfate, a sodium chlorite, and hydrogen peroxide. In an illustrative embodiment, the unpatterned device layer is a metal layer and a surface activating solution is applied to the surface of the metal layer. In an exemplary embodiment, the surface activation solution can be applied for a predetermined time and then washed away, such as, but not limited to, 10 seconds, 20 seconds, 30 seconds, 60 seconds, or longer. In an exemplary embodiment, the surface activating solution can be applied by dipping the surface into a bath containing a surface activating solution. In an illustrative embodiment, the surface activating solution can be applied by spraying the surface with a surface activating solution, or any other suitable method. In an exemplary embodiment, the surface activation solution is washed away from the surface using a wash liquid such as, but not limited to, an alcohol solution, ethanol, propanol, isopropanol, and acetone. In an illustrative embodiment in which the surface is a copper layer (for example, a PCB) surface, an aqueous solution is activated with a surface concentration of CuCl ₂ (or any divalent copper salt) having a concentration of 0.5 to 1.0, and the primer layer is used. The copper surface was at least partially formed by immersing it in a bath containing a surface activating solution for 30 seconds. In an illustrative specific example of a surface in which the surface is a copper layer (eg, of a PCB), a surface activated aqueous solution of Na ₂ S ₂ O ₈ (or any persulfate) having a concentration by weight of 0.5 to 1.0 is used, and the primer is applied. The layer was at least partially formed by dipping the copper surface into a bath containing the surface activation solution for 30 seconds. In an illustrative specific example of a surface in which the surface is a copper layer (for example, a PCB), an aqueous solution of a surface of H ₂ O ₂ having a weight percentage of 10 is used, and the primer layer is immersed in the surface containing the surface activation solution by immersing the copper surface. The bath was formed at least partially in 30 seconds. In an illustrative embodiment in which the surface is a copper layer (for example, a PCB) surface, an aqueous surface solution of FeCl ₃ having a weight percentage of 20 is used, and the primer layer is immersed in a bath containing a surface activation solution by immersing the copper surface. Formed at least partially in 10 seconds. In an exemplary embodiment in which the surface is a copper layer (for example, a PCB) surface, an aqueous solution of a surface of HCrO ₄ /H ₂ SO ₄ having a weight percentage of 5 is used, and the primer layer is immersed in the copper surface by containing The bath of the surface activation solution was at least partially formed in 30 seconds. In an illustrative embodiment in which the surface is a copper layer (for example, a PCB) surface, an aqueous solution is activated with a surface concentration of NaClO ₂ having a concentration of 5, and the primer layer is immersed in a bath containing a surface activation solution by immersing the copper surface. Formed at least partially in 60 seconds.

In an illustrative embodiment in which a resist ink is printed onto a primer layer using an ink jet printer, the substrate can be at about "chamber" temperature, such as in the range of 20 ° C to 30 ° C, or can be elevated. At temperatures, for example up to 100 °C. In an exemplary embodiment, the two-component etch mask can have a thickness of at least 0.01 μm. In an exemplary embodiment, the two-component etch mask can have a thickness of less than 12 μm.

In an exemplary embodiment of the invention, a primer layer is deposited onto the substrate, and then an etch mask ink is deposited onto the primer layer using inkjet printing and then baked to form an etch mask layer. Shortly after contact with the primer layer, the droplets of the etch mask ink interact with the primer layer to effectively stop or "freeze" the ink droplets, thereby greatly reducing or eliminating further diffusion and/or migration. The position is the result of a chemical reaction between the first reactive component in the primer layer and the second reactive component in the etch mask ink. Additionally, one or more components of the etch mask ink react with one or more components of the primer layer to form a two-component etch mask material that is relatively insoluble in the etch mask ink and relatively insoluble in the etch mask The etch solution to which the hood will be used (where the relatively insoluble is defined herein as an etch mask ink component relative to the reaction to form a two-component etch mask). For example, the etch mask ink may be aqueous and the etch mask material resulting from such reaction is insoluble in water, and the etch solution may be an acidic etch solution, and the etch mask material resulting from such reaction is insoluble. In the acidic etching solution.

In an exemplary embodiment, coating an unpatterned device layer (such as a copper layer) with an undercut prevention material (such as a corrosion resistant material) may be suitable for using an etch mask to protect the device layer material from any wet etching. method. Other metal layers may be used instead of copper in exemplary embodiments including, but not limited to, aluminum, stainless steel, gold, and metallic alloys. Illustrative specific examples of the invention include introducing an undercut reducing material in the form of a primer layer prior to applying the photoresist layer to the unpatterned device layer, for example via lamination, slit coating, or spin coating. It is then patterned via light exposed to a selected wavelength (eg, UV light), patterned through a reticle, or via direct laser imaging.

The effect of the undercut reducing material during the chemical etching process can mitigate (eg, reduce, eliminate) the occurrence of undercuts of device layer features caused by the patterning process. Thus, after the chemical etching process, due to the reduction or elimination of the undercut, device layer features having sidewalls that are more vertical and less inclined than the device layer formed without the undercut reducing material can be formed. When applied to a patterned device layer comprising a conductive material having the function of carrying a current or electrical signal, various embodiments of the present invention can enhance the overall performance of the electrical circuit thus formed, improve the overall conductivity of each conductive feature, and enhance the frequency. Responsively, and enabling, the fabrication of patterns having higher density and thinner features and thinner spacing between features. Similar benefits can also be obtained in components of patterned device layers, such as optical or insulating patterned features, that use non-metallic materials.

It is believed that during a conventional wet etch process, the liquid etch is performed as the liquid etchant descends (eg, toward the substrate) through the thickness of the device layer material being etched in those regions not covered by the etch mask. The agent is also advanced laterally into the side surfaces (e.g., sidewalls) of those portions of the device layer material that are covered by the etched mask. As the etch depth increases, more sidewalls are exposed to the lateral etch, such that the sidewall portion closest to the etch mask is exposed to the liquid etchant for a longer time than the sidewall portion closest to the substrate, and thus is subject to increased lateral etch, thus The sidewalls imparting the resulting patterned device layer features are undercut. In other words, the time during which the etchant reacts with the device layer material to remove portions of the device layer material increases with distance from the substrate. Without wishing to be bound by any particular theory, it is believed that in conventional wet etching procedures, whether by immersion or spraying or spraying of an etchant, between the etchant and the portion of the device layer material remote from the substrate. The additional reaction time results in lateral inward erosion (removal) of the device layer material in the region of the device layer material directly below and adjacent to the etch mask feature, although the purpose of the etch mask is to prevent removal of device layer material in those regions. . Further explanation and description of this phenomenon is provided below in conjunction with Figures 4B-5C.

As discussed in various exemplary embodiments in accordance with the present invention, the reaction between the etchant and the device layer material corresponding to portions of the side surfaces (or equivalently, sidewalls) of the patterned device layer features is in a wet etch process. The period is alleviated (eg, reduced, prevented, suppressed), thereby mitigating the formation of an undercut shape on the side surface.

1A-5C all illustrate various stages of processing a device to form a patterned device layer on a substrate (or equivalently forming a patterned device layer feature on a substrate) in accordance with various conventional methods. In an illustrative embodiment, the device is a PCB during manufacturing and the device layer material is a conductive material. However, those skilled in the art will appreciate that references to PCBs are only non-limiting and exemplary, and various applications are encompassed within the scope of the present invention, such as the various electronic and optical components mentioned above. Referring now to Figures 1A-1D, various views of apparatus 100 undergoing processing in accordance with one conventional method to form patterned device layer features are illustrated. 1A is a plan and side view of device 100 including a substrate 102 on substrate 102 having an unpatterned device layer 104 disposed thereon.

The substrate 102 itself may comprise multiple layers such as, but not limited to, one or more unpatterned or patterned device layers. For example, although the unpatterned device layer 104 is shown on one side of the substrate 102 (eg, "top" in a patterned orientation), the present invention contemplates "double-sided" processing of the device 100, for example, where the substrate 102 includes a second unpatterned device layer positioned to be on opposite sides (eg, "bottom") of the substrate 102. In an exemplary embodiment, such a "bottom" side unpatterned device layer is subjected to a patterning process similar to the "top" side of the unpatterned device layer 104, and such "bottom" side is patterned in whole or in part The ground occurs before, after, or during the "top" side patterning of the unpatterned device layer 104. In an illustrative embodiment, substrate 102 can include one or more patterned device layers processed in accordance with one or more illustrative embodiments, such as, but not limited to, in a manner similar to that used to process unpatterned device layer 104. The way.

In an illustrative embodiment, device 100 is a PCB during fabrication, unpatterned device layer 104 comprises a conductive material such that it becomes an unpatterned conductive device layer, and substrate 102 comprises one or more layers of electrically insulating material. It is configured to provide a "top" electrically insulating surface and a "bottom" electrically insulating surface, and the unpatterned conductive device layer 104 is positioned adjacent to the "top" electrically insulating surface. A second unpatterned conductive device layer is bonded into the substrate 102, and the second unpatterned conductive device layer is positioned adjacent to the "bottom" electrically insulating surface (where such a "bottom" electrically insulating surface is on the substrate 102 And not shown in FIG. 1), and the "bottom" surface of the substrate 102, that is, the surface of the substrate 102 on the opposite side of the surface adjacent to the unpatterned device layer 104, is the second unpatterned The surface of the conductive device layer.

In an exemplary embodiment, device 100 is a PCB during fabrication and substrate 102 has an electrically insulating surface over a region including at least a portion of the interface between substrate 102 and unpatterned device layer 104. In an illustrative embodiment, substrate 102 can comprise a layer of electrically insulating material such as, but not limited to, a composite comprising woven glass bonded by an epoxy or other material. Such an electrically insulating material can have a thickness, for example, in the range of from about 0.001 Å to about 0.05 Å. In an exemplary embodiment, substrate 102 can comprise a plurality of alternating layers of electrically insulating material and electrically conductive material, further comprising at least two electrically insulating layers, each layer comprising woven glass bonded by epoxy or other material and having A thickness between 0.001 Å and 0.05 Å, such as a "core" layer and a layer comprising a prepreg sheet (which may be referred to as a "prepreg"), and between the electrically insulating layers. At least one patterned conductive layer, wherein the "top" surface of the substrate 102 bordering the unpatterned device layer 104 is the surface of one of the at least two electrically insulating layers. In an exemplary embodiment, the prepreg sheet comprises an FR4 grade epoxy laminate. In an illustrative embodiment, the core layer comprises an FR4 grade epoxy laminate.

Unpatterned device layer 104 may comprise a layer of electrically conductive material, such as, for example, a metal or metal alloy, including but not limited to copper, aluminum, silver, gold, or other electrically conductive materials, which are familiar to those skilled in the art. In an exemplary embodiment, unpatterned device layer 104 is a copper foil laminated to substrate 102, wherein the interface surface between substrate 102 and unpatterned device layer 104 is electrically insulating; however, other conductive materials It is considered to be within the scope of the invention.

Referring now to FIG. 1B, in the next stage of processing, an etch mask 106 is formed on the exposed surface 110 of the unpatterned device layer 104. The etch mask 106 can be formed in a desired pattern 108, such as a line corresponding to where it is desired to pattern the device layer lines on the device 100 after processing, as shown in FIG. 1B. In other words, the etch mask 106 can include a resist material deposited over the unpatterned device layer 104 at a location corresponding to the desired feature of the device layer in the device 100. The etch mask 106 can comprise materials such as, for example, polymers, oxides, nitrides, or other materials. In an exemplary embodiment, the etch mask material is a polymer formed using a negative photoresist material such as, but not limited to, SU-8 series photoresists supplied by MicroChem Corp., 200 Flanders Road, Westborough, MA 01581 USA. one. In an illustrative embodiment, the etch mask material is a polymer formed using a positive photoresist material such as, but not limited to, ma-P 1200 supplied by micro resist technology GmbH., Köpenicker Str. 325, 12555 Berlin, DE. One of a series of photoresists. The etch mask 106 can be patterned over the surface of the unpatterned device layer 104 by methods such as screen printing, ink jet printing, photolithography, gravure printing, stamping, photo engraving, or other methods. After the etch mask 106 is applied to the surface 110 of the unpatterned device layer 104, the device 100 is exposed to an etchant (such as a chemical etchant) that removes the unpatterned device from those areas that are not protected by the etch mask 106. The material in layer 104 results in the formation of patterned device layer 114, as shown in Figure 1C. Such a chemical etchant can include a compound that has a corrosive effect on the material of the unpatterned device layer 104. In an exemplary embodiment, unpatterned device layer 104 is a conductive layer, and such chemical etchant can include, but is not limited to, ammonium persulfate, ferric chloride, or a corrosive effect on the material of unpatterned device layer 104. Other compounds. In one specific example, the apparatus is not patterned conductive layer 104 comprises copper, and the etchant used is copper (CuCl ₂₎ chloride. Those skilled in the art are familiar with various chemical etchants suitable for removing the material of the unpatterned device layer 104.

With continued reference to FIG. 1C, the etchant begins to dissolve (eg, etch) the material of the unpatterned device layer 104 from the exposed top surface 110 when the unpatterned device layer 104 is exposed to the etchant. As the material of the unpatterned device layer 104 is removed, the etchant can also remove portions of the material of the unpatterned device layer 104 under the etch mask 106, leaving the non-straight and non-vertical sidewalls 112. For example, as shown in FIG. 1C, in apparatus 100 fabricated in accordance with the method illustrated in FIGS. 1A-1D, sidewalls 112 of features of patterned device layer 114 that are produced in accordance with pattern 108 of etch mask 106 may be tapered. , for example, from a first feature width W1 at the interface between the patterning device layer 114 and the etch mask 106, to an interface between the substrate 102 and the patterning device layer 114, a second wider than the first feature width Cone of feature width W2. FIG. 1D illustrates device 100 after etch mask 106 is removed, exposing patterned device layer 114. The taper presented by the sidewalls 112 of the features of the patterning device layer 114 in Figure 1D is an illustration of the "undercut" sidewalls and will be discussed in further detail below in connection with Figures 4A-4C. Other shapes and arrangements of undercut sidewalls may also occur, and may include sidewalls that are substantially not straight and sidewalls that are not substantially perpendicular to the surface of the substrate from which they are formed.

2A-2C, a method of forming an etch mask 206 having a pattern 208 of conductive lines is illustrated. Device 200 having substrate 202 and unpatterned device layer 204 covers the entire area of unpatterned device layer 204 (ie, blanket coating) with unpatterned resist layer 216. The unpatterned resist layer 216 is then exposed to light (eg, UV light) in a pattern such that the exposed areas are relatively less likely to be removed in subsequent development processes (so-called negative processing), or the exposed areas are subsequently developed Relatively easy to remove in the program (so-called positive processing). Such patterning using exposure can be performed by illuminating the light through the reticle, for example, as in a so-called lithographic process, or by delivering a series of focused lights to the resist layer 216 as a function of time (eg, The laser beam is in the form of a pulse or scan, a so-called direct write process. The development process removes the material in the unpatterned resist layer 216 corresponding to the patterned exposure to provide a patterned etch mask 206 having the pattern 208, as shown in Figure 2C. The developing process can include immersing the device 200 in a liquid developer that dissolves or etches materials that are relatively easier to remove in the unpatterned etch mask layer 216, such as, but not limited to, in a negative type program In the case where the developer liquid is soluble in the material of the unpatterned resist layer 216 that has not been exposed to UV light, in the case of a positive-type procedure, the developer liquid is soluble in the unpatterned resist layer. A material that has been exposed to UV light. The portion of the unpatterned device layer 204 that is not protected by the etch mask 206 is then removed as discussed above in connection with FIG. 1D, resulting in a device 200 having a patterned device layer having features and representations of the pattern 208. Cut out the bottom.

Alternatively, the etch mask can be deposited directly onto the unpatterned device layer in a desired pattern without the intermediate step of patterning the unpatterned resist layer in the specific example of Figures 2A-2C. For example, referring now to Figures 3A and 3B, the etch mask 306 can be formed directly over the unpatterned device layer 304 of the device 300 in a desired pattern 308 of lines corresponding to the desired pattern on the resulting device. The location of the features of the device layer. The etch mask 306 can be deposited on the unpatterned device layer 304 in a desired pattern 308 by, for example, inkjet printing, lamination, screen printing, gravure printing, stamping, or other methods. In an illustrative embodiment, an etch mask 306 is formed over the unpatterned device layer 304 using inkjet printing, wherein an inkjet printhead having a plurality of nozzles ejects liquid resist ink droplets onto the device 300 A coating of the liquid resist ink corresponding to the pattern 308 is formed, and the coating of the liquid resist ink is subsequently processed to convert the liquid coating into an etch mask 306. In another illustrative embodiment, the treatment of the liquid resist ink comprises drying and/or baking the device to form a solid etch mask 306 from the liquid coating. In an illustrative embodiment, an etch mask 306 is formed over the unpatterned device layer 304 using an inkjet printer that includes one or more print heads including a plurality of nozzles, a substrate that supports the substrate a support, a stage for relatively moving the plurality of nozzles and the substrate, a motion control system for controlling the relative positions of the substrate and the nozzle, and a control for controlling the emission of the nozzle to deliver the droplets to the substrate in a desired pattern Nozzle control system on. It is contemplated in the present invention that in any particular example in which ink coating is used to deposit a liquid coating, an inkjet printing system such as described herein can be used.

4A-4C illustrate a conventional method for removing material from unpatterned device layer 404 from device 400 and depicting what would have occurred during the wet etch process that would result in undercut. In FIG. 4A, unpatterned device layer 404 is covered by etch mask 406 corresponding to pattern 408. Device 400 is then exposed to chemical etchant 418. In the illustrative embodiment of FIG. 4B, the exposure is performed by immersing the etchant 418. Etchant 418 removes material from unpatterned device layer 404 (from Figure 4A) to create a partially patterned device layer 405. For example, in the particular example of FIG. 4B, etchant 418 includes a liquid contained within container 420, such as a limited solution, and immerses device 400 with etch mask 406 (FIG. 4B) in etchant 418. Medium, as shown in Figure 4B. Once the exposed portion of the top surface 410 (FIG. 4A) of the unpatterned conductive layer 404 is etched away and the sidewalls 412 begin to form, the sidewalls 412 are exposed to the etchant 418 and the etchant 418 removes material from the sidewalls 412, resulting in The tapered, undercut shape of the features of the patterning device layer 414 shown in Figure 4C. In other words, once the top surface 410 of the unpatterned device layer 404 is etched away, the etchant 418, which can function in all directions, will laterally attack the material containing the device layer below the etch mask 406 (regardless of the device layer In its unpatterned state, ie 404; partially patterned state, ie 405; or patterned state, ie 414). The amount of material of the device layer removed by etchant 418 may depend on the amount of time the device layer material is exposed to etchant 418. Thus, as the etchant 418 travels through the thickness of the portion of the patterning device layer 405 (ie, in a direction perpendicular to the plane of the substrate 402), the portion of the sidewall 412 that is closer to the etch mask 406 is closer to the substrate 402 than the sidewall 412. Portions are exposed to the etchant 418 for a longer period of time, and the etching process thereby imparts a tapered (ie, undercut) shape to the sidewall 412 as shown in FIG. 4C. In other words, the time during which the etchant reacts with the material in the device layer to remove such material from the device layer increases with distance from the substrate. Without wishing to be bound by any particular theory, it is believed that the additional reaction time between the etchant and the material of those portions of the device layer remote from the substrate results in a device from the device layer region directly below or adjacent to the etch mask. The lateral inward erosion (removal) of the layers of material, although the purpose of etching the mask is to prevent removal of the material of the device layer in those areas.

5A-5C, which show a specific example of another conventional method. The method of Figures 5A-5C is similar to that described in connection with Figures 4A-4C and includes forming an etch mask 506 over the unpatterned device layer 504 of device 500, as shown in Figure 5A. Instead of immersing device 500 in etchant 518 as described above in connection with FIG. 4B, etchant 518 is introduced into jet 522 that is directed to device 500, which may be in container 520, as shown in FIG. 5B. Excess etchant 518 can flow into the vent 524 of the vessel 520 or be otherwise collected, such as for recycling or other processing. Because etchant 518 acts omnidirectionally, a tapered or undercut is formed on the resulting sidewall 512 of the features of patterned device layer 514, as shown in Figure 5C.

As noted above, undercut sidewalls having features of the patterned device layer formed on the device introduce various limitations in the size and shape of the features that can be formed. For example, as discussed above, the tendency to form undercuts may limit the minimum feature width or minimum feature to feature spacing that can be produced, thereby limiting the feature density on the device. Maximizing the density of features on the device can improve performance in a variety of applications. In various embodiments, the device layer comprises a conductive material, the device is a PCB, and the undercut tendency may limit the minimum feature width, the minimum feature to feature pitch, and the maximum feature density.

6A-17 illustrate various specific examples of methods for mitigating (eg, reducing or eliminating) undercuts that occur during conventional processing. For example, referring now to FIG. 6A, device 600 has an unpatterned device layer 604 above substrate 602. The unpatterned device layer 604 can be by chemical vapor deposition, physical vapor deposition, lamination, slit coating, spin coating, ink jet printing, screen printing, nozzle printing, gravure printing, bar coating, or any Other suitable methods are applied to the substrate, such as those familiar to those skilled in the art. The unpatterned device layer 604 is coated with an anti-corrosion layer 629 prior to forming the etch mask 628 over the anti-corrosion layer 629. The anti-corrosion layer 629 can be by chemical vapor deposition, physical vapor deposition, lamination, slit coating, spin coating, ink jet printing, screen printing, nozzle printing, gravure printing, bar coating, or any other suitable The method is applied to the substrate, such as those familiar to those skilled in the art. In some embodiments, the anti-corrosion layer 629 includes a "primer" layer and an etch mask 628 is formed by depositing a liquid resist ink on the primer layer, such as, but not limited to, drying. The subsequent processing of the baking is converted into an etch mask 628. In various embodiments, as previously described, such liquid resist inks can be delivered to device 600 in the form of droplets via inkjet printing, and can be combined with corrosion resistant layer 629 (in this case, the primer layer) Interaction) such that droplets are effectively (eg, on the order of microseconds) effectively stop moving or "freezing" in place when in contact with the surface of the primer, thereby causing further displacement of the ink droplets on the surface of the primer or The diffusion is greatly reduced or completely stopped, as further discussed in International Publication No. WO 2016/193978 A2 and WO 2016/025949 A1, which is incorporated herein by reference. Such liquid resist inks can also further produce a two-component material via interaction with such a primer layer that at least partially forms a resist mask.

In various embodiments, referring to FIG. 6A, device 600 is a PCB, and unpatterned device layer 604 includes a conductive material such as copper, aluminum, gold, and/or other metal adjacent to unpatterned conductive device layer 604. The surface of the substrate 602 is electrically insulating.

In an exemplary embodiment, the anti-corrosion layer 629 can comprise a material selected based on its ability to prevent the corrosive effects of the chemical etchant used to remove the material of the unpatterned device layer 604 of the device 600. As a non-limiting example, corrosion resistant layer 629 can include, but is not limited to, a polymer; an organic compound, such as comprising one or more imine groups, one or more amine groups, one or more - azole groups, One or more hydrazine groups, one or more organic compounds of an amino acid; Schiff base; or other materials. In other exemplary embodiments, the corrosion resistant layer 629 can comprise an inorganic material such as a chromate, a molybdate, a tetraborate, or another inorganic compound. In some exemplary embodiments, the corrosion resistant layer 629 can comprise a reactive component, such as one or more reactive cationic groups comprising a polycation and/or a multivalent cation. The cationically reactive component is capable of attaching to a metallic surface, such as a copper surface.

In some embodiments, the anti-corrosion layer 629 can be formed by applying a liquid anti-corrosion ink over the unpatterned device layer using any known application method, such as, but not limited to, spray coating, spin coating, nozzle printing. The bar coating, screen printing, painting, ink jet printing, etc., is then processed to convert the liquid coating to an anti-corrosion layer 629. In some embodiments, the corrosion resistant layer 629 can be referred to as a primer layer, and the liquid corrosion resistant ink can be referred to as a primer ink. The liquid anti-corrosion ink may comprise a solution, which may comprise a polyimine such as, for example, a polyethyleneimine having a low molecular weight or a high molecular weight, such as a linear polyethyleneimine or a branched polyethyleneimine. As a non-limiting example, the molecular weight can range from about 800 to about 2,000,000.

In some embodiments, in order for the liquid anti-corrosion ink to be ejected via an inkjet printhead, the liquid ink can be an aqueous solution, which can include additional reagents such as propylene glycol, n-propanol, and wetting additives (such as supplied by Evonik Industries). TEGO 500).

In some embodiments, the thickness of the corrosion resistant material layer 629 can range from about 0.03 [mu]m to about 1.1 [mu]m. In some embodiments, the method can include drying the applied ink using any drying method to form a solid coating. In some embodiments, the method can include baking the applied ink using any drying method to form a solid coating.

As a further non-limiting example, if present, the cationically reactive component of corrosion resistant material layer 629 can comprise polyamidamine, such as polyethyleneimine, polytetramine, long chain quaternary amine, poly Tertiary amines; and polyvalent inorganic cations such as magnesium cations, zinc cations, calcium cations, copper cations, iron cations and ferrous cations. The polymerizable component can be introduced into the formulation as a soluble component or as an emulsion.

The anti-corrosive material layer 629 can be applied to the unpatterned device layer 604 using any suitable printing or coating method including, but not limited to, ink jet printing, spray coating, metering bar coating, roll coating, dipping Coating, spin coating, screen printing, lamination, stamping and others. The anti-corrosion layer 629 can be applied uniformly over the unpatterned device layer 604, or in a desired pattern, such as the desired pattern of the patterned device layer 630 as defined in the pattern 608 (according to Figure 6).

In the illustrative embodiment of Figures 6A-6D, the corrosion resistant layer 629 can comprise a "primer" layer, and an etch mask 628 can be formed by depositing a liquid resist ink on the primer layer. The agent ink is converted to an etch mask 628 via subsequent processing such as, but not limited to, drying or baking. In various embodiments, such drying can include baking, such as, but not limited to, at 70 ° C or higher. In various embodiments, such liquid resist inks may be delivered to device 600 in the form of droplets via inkjet printing, as described previously, and may interact with the primer layer such that such droplets are at the bottom When the lacquer surface is in contact, it quickly stops (eg, on the order of microseconds) from moving or "freezing" into place, thereby further reducing or completely stopping the ink droplets on the surface of the primer, as discussed further in International Publication No. WO2016. /193978 A2 and WO2016/025949 A1, incorporated herein by reference. Such a liquid resist ink can further produce a two-component material via interaction with such a primer layer that at least partially forms an etch mask.

The etch mask 628, or a liquid resist ink used to fabricate such an etch mask 628 (according to various embodiments as described above) may comprise a polymerizable component that is water soluble and may include an anionic group group. The anionic polymer may be selected from the group consisting of acrylic resins and styrene-acrylic resins in the form of their dissolved salts. The anionic polymer may be selected from sulfonic acid resins in the form of their dissolved salts, such as sodium, ammonium neutralized or amine neutralized forms. In a specific example of utilizing a liquid resist ink, the liquid ink can include additional reagents for improving the printing or other deposition qualities of the material.

The etch mask 628, or liquid resist ink used to fabricate such an etch mask 628 (according to certain embodiments as described above) may comprise a reactive component, which may be water soluble and may include Reactive anionic group. Non-limiting examples of anionic reactive components can include at least one anionic polymer (in base form) having a pH above 7.0. The anionic polymer may be selected from the group consisting of acrylic resins and styrene-acrylic resins in the form of their dissolved salts. The anionic polymer may be selected from the group consisting of sulfonic acid resins in the form of their dissolved salts such as, but not limited to, sodium salt forms, ammonium or amine neutralized forms, and in the form of polymer emulsions or dispersions. The polymerizable component can be introduced into the formulation as a soluble component or as an emulsion.

Referring to FIG. 6B, the anti-corrosion layer 629 and the etch mask 628 can be printed directly on the device 600. In an exemplary embodiment, the anti-corrosion layer 629 can be formed via printing in a desired pattern (such as pattern 608) over the unpatterned device layer 604 to facilitate fabrication of a corresponding patterned device layer 630 (eg, Shown in 6). The anti-corrosion layer 629 may be deposited in a range from about 5 nm to about 100 nm, at a thickness of about 100 nm or less, or at a thickness of about 1 μm or less. Other thicknesses of the corrosion resistant material layer 629 are considered to be within the scope of the invention, and may depend on the particular application. An etch mask 628 is then formed via printing in a desired pattern (such as pattern 608) over the anti-corrosive material layer 629 to facilitate fabrication of a corresponding patterned device layer 630 (as shown in FIG. 6). For example, the etch mask 628 can be deposited to have a thickness in the range of about 1 μm to about 5 μm, or about 5 μm or less, or about 15 μm or less.

Device 600 is then introduced into an etchant, such as liquid chemical etchant 418 or 518 as discussed in connection with Figures 4B and 5B. As shown in Figures 6C and 6D, the presence of the anti-corrosive material layer 629 can help reduce the amount of undercut of the features of the patterned device layer 630. For example, the features of the patterning device layer 630 can exhibit a first width W1 proximate to the anti-corrosion layer 629 and a second width W2 proximate to the substrate 602. In some exemplary embodiments, the difference between the widths W1 and W2 causes the features of the patterning device layer 630 to assume tapered sidewalls 632 (i.e., features of the patterned device layer 630 may exhibit a degree of undercut). The undercut exhibited by the features of the patterning device layer 630 can be less than the undercut exhibited by the features of the patterning device layers 114, 414 (Figs. 1D and 4D) as discussed above. Various measurements can be used to quantify the extent of the undercut, as discussed in more detail below in connection with Figures 10 and 11.

In the illustrative embodiment of FIGS. 7A-7C, a corrosion resistant layer 729 is fully carpet deposited on the surface of the unpatterned device layer 704 disposed on the substrate 702. Such blanket coating can be by, for example, but not limited to, chemical vapor deposition, physical vapor deposition, lamination, ink jet printing, spray coating, metering rod coating, roll coating, dip coating, spin coating, stencil Printing, nozzle printing, or other methods are used to accomplish this. The etch mask 728 can be formed over the anti-corrosion layer 729 in a desired pattern, such as pattern 708, as discussed above with respect to various specific examples. This method is carried out similarly to the specific examples of Figures 6A-6C described above. For example, device 700 having corrosion resistant layer 729 and etch mask 728 is exposed to an etchant, such as etchant 418 or 518 discussed in connection with Figures 4B and 5B. As shown in FIG. 7B, device 700 is placed in container 720 and etchant 718 is sprayed over the surface of device 700 on which etch mask 728 is disposed. The etchant 718 can remove the anti-corrosion layer 729 from the surface of the unpatterned device layer 704 and expose the material of the unpatterned device layer 704 removed by the etchant 718 as shown in FIG. 7B to form a pattern with sidewalls 732. Device 730, as compared to sidewall 112 associated with patterned device layers 114, 414 fabricated in accordance with conventional methods, sidewall 732 exhibits a reduced degree of undercut. The portion of the patterning device layer 705 reflects the device layer after removing the anti-corrosion layer 729 from those regions exposed by the etch mask and some of the material of the device layer itself has been etched away, and before the etch is sufficiently developed to form the patterning device 730 Intermediate state.

Referring now to Figures 8A-8D, a portion of the method of the specific examples of Figures 7A-7C is illustrated in greater detail. In FIG. 8A, a jet 822 of an etchant (such as etchant 718 in FIG. 7B) strikes the anti-corrosion layer 829 and the etch mask 828 surface deposited on the unpatterned device layer 804 on the substrate 802. The anti-corrosion layer 829 can preferentially adhere to the surface of the material of the device layer and can also be at least partially dissolved in the etchant 718, while the resist material 828 is substantially insoluble in the etchant 718. Jet 822 of etchant 718 may contain sufficient kinetic energy to remove anti-corrosion layer 829 from unpatterned device layer 804 in those regions exposed by the etch mask, as shown in Figure 8B, and then etchant 718 may begin to be removed. The material of the unpatterned device layer 804 that is not covered by the resist material 828 and forms a partially patterned device layer 805 as shown in Figure 8C. FIG. 8D illustrates device 800 after partial patterning device layer 805 is sufficiently etched to form patterned device layer 830. As shown in Figure 8D, the patterning device 830 has sidewalls 832 that exhibit less undercut than sidewalls fabricated according to conventional methods described in connection with Figures 1A-5C. Although the patterning device 830 shown in FIG. 8D has a slight undercut, the present invention contemplates a patterned device layer that is substantially free of undercuts (ie, substantially straight and perpendicular to the surface of the substrate 802) (eg, conductive )feature.

9A-9C, another embodiment of a method for forming a patterned device layer 930 on device 900 is shown. The unpatterned device layer 904 disposed over the substrate 902 is shielded by the anti-corrosion layer 929 and the etch mask 928. Device 900 and etchant 918 are introduced into vessel 920 such that the device is immersed in etchant 918 in Figure 9B. As shown in Figure 9C, the resulting patterning device layer 930 of the device 900 has sidewalls 932, and the sidewalls 932 exhibit a comparison compared to the undercuts exhibited by the conductive features 114 (Figure 1D) associated with conventional methods. A small degree of undercut.

Referring now to Figure 10, an enlarged view of apparatus 100 discussed in connection with the conventional methods of Figures 1A-5C is shown. In FIG. 10, features of the patterning device layer 114 exhibit tapered sidewalls that extend between the interface of the etch mask 106 and the patterning device layer 114 and the interface between the patterning device layer 114 and the substrate 102. The patterning device layer feature 114 exhibits a first width W1 at the interface of the patterning device layer 114 and the etch mask 106, and exhibits a second width W2 at the interface of the patterning device layer 114 and the electrically insulating substrate 102. FIG. 10 is drawn for illustrative purposes, and variations in profile may occur, but in general, the patterning device layer 114 has a wider width at the interface with the substrate than at the interface with the resist material. It should be noted that the etch mask 106 has a width W3 which is contemplated by the present invention to be greater than, less than, or equal to the width W2.

Reference is now made to Fig. 11, which is an enlarged view of apparatus 1100 similar to apparatus 600, 700, 800, or 900 shown in Figs. 6A-9C. In this illustrative embodiment, the features of the patterning device layer 1130 exhibit a first width W1 at the interface between the patterning device layer 1130 and the anti-corrosion layer 1129, and between the patterning device layer 1130 and the substrate 1102. A second width W2 is exhibited at the interface. It should be noted that the etch mask 1128 has a width W3 which is contemplated by the present invention to be greater than, less than, or equal to the width W2.

An exemplary measure of the degree of undercut is the etch factor F, which is the ratio of the width difference between the widest portion and the narrowest portion of the features of the patterned device layer to the height of the features of the patterned device layer. Therefore, the etch factor F is defined as H/X, where H is the height (H) of the line and X is equal to (W2-W1)/2, that is, between the width of the base portion (W2) and the width of the top portion (W1). The difference is divided by 2. Figure 11 illustrates the relationship between H and X. Exemplary values of the etch factor F of the patterned device layer features of the present invention are discussed below in connection with Examples 1-3. As a non-limiting example, device layer features associated with devices fabricated in accordance with various illustrative embodiments of the present invention may exhibit an etch greater than 2, greater than 5, greater than 7, or greater, such as greater than 10, greater than 20, and the like. Factor F. As another example, when the value of X is near zero, the etch factor F of the conductive features having sidewalls that are near vertical lines (ie, exhibiting no undercut) will approach infinity. Measurements of H, W1, and W2 can be performed using a variety of microscopy techniques for measuring surface profile, cross-section, and film thickness, such as, but not limited to, surface profile measurements, scanning electron microscopy, ellipsometry, and confocal microscopy.

While not wishing to be bound by a particular theory, the inventors believe that during the etching process, a portion of the layer of corrosion resistant material separates from the layer and adheres to and/or adsorbs to the sidewalls of the device layer under the etch mask to mitigate Undercut. Figures 12A and 12B depict this phenomenon.

Figure 12A shows a cross-sectional view of device 1200 during an intermediate processing step in a patterning method, in accordance with various illustrative embodiments of the invention. As shown, the portion of the patterning device layer 1205 on the substrate 1202 is undergoing an etching process. FIG. 12B shows an enlarged view of a portion of FIG. 12A at the interface between the sidewalls 1232 of the partially patterned device layer 1205 and the anti-corrosion layer 1229. As shown in FIG. 12B, when device 1200 is exposed to etchant 1218, corrosion resistant material portion 1246 comprising corrosion resistant layer 1229 is separated from corrosion resistant layer 1229 by, for example, but not limited to, partially dissolved by etchant 1218. The corrosion resistant layer, and such corrosion resistant material then travels and adheres to and/or adsorbs onto the sidewalls 1232. In other words, the presence of etchant 1218 can facilitate the displacement of corrosion resistant material portion 1246 comprising corrosion resistant layer 1220 from corrosion resistant material layer 1229 to sidewall 1232 of partial patterning device layer 1230 during the etching process. The presence of the corrosion resistant material portion 1246 on the sidewalls 1232 can then inhibit the etchant 1218 from corroding on the sidewalls 1232, thereby reducing (e.g., reducing or eliminating) the amount of undercut exhibited in the resulting patterned device layer 1230. In various exemplary embodiments, it is believed that at least two processes contribute to these phenomena, wherein in one process, the corrosion resistant material is dissolved by the etchant, while in another synchronization process, the resistance dissolved in the etchant The corrosive material is adsorbed onto and/or attached to the sidewall 1232. In various exemplary embodiments, the rates of the first and second processes are such that the corrosion resistant material portion 1246 is formed and maintained during the etching process to reduce (eg, reduce or eliminate) the amount of undercut produced.

As shown in FIG. 12B, it is believed that in some cases, the corrosion resistant material portion 1246 adsorbed to the sidewall 1232 can exhibit a generally tapered shape with the adhesion layer of the corrosion resistant material and/or the adsorption layer 1246 near the corrosion resistant material layer 1229. A greater thickness is exhibited and exhibits a reduced thickness along layer 1246 in a direction away from the layer of corrosion resistant material 1229 and toward the substrate.

13A, 13B, and 13C illustrate additional examples of processes in which particles 1348 of corrosion resistant material are believed to be separated from corrosion resistant layer 1329 and attached to and/or adsorbed onto sidewalls 1332 of partial patterning device layer 1305 of device 1300. . 13B and 13C show enlarged views of the interface between the corrosion resistant material layer 1329 and the partially patterned device layer sidewalls 1332. As shown in FIG. 13B, particles 1348 of corrosion resistant material are separated from the layer of corrosion resistant material 1306. In FIG. 13C, the separated particles 1348 are attached to and/or adsorbed onto the sidewalls 1332 of the partial patterning device layer 1305. The separated particles 1348 can be attached to and/or adsorbed onto the sidewalls 1332 in a generally reduced thickness pattern in a direction away from the layer of corrosion resistant material 1329. It is believed that in various circumstances, the separated particles 1348 can be adsorbed onto and/or attached to the sidewalls 1332 in a substantially uniform pattern, a substantially random pattern, or in some other pattern. During the etching process, the presence of particles 1348 on sidewalls 1332 can inhibit the action of etchant 1318 and mitigate (eg, reduce or eliminate) undercuts that occur on portions of patterned device layer 1305. As described above with respect to Figure 12, in various exemplary embodiments, it is believed that at least two processes contribute to these phenomena, wherein in one process, the corrosion resistant material is dissolved by the etchant while in another process of synchronization The corrosion resistant material dissolved in the etchant is adsorbed onto and/or attached to the sidewall 1332, and in various embodiments, the rates of the first and second processes are such that a portion of the corrosion resistant material is formed and maintained during the etching process 1346 to reduce (eg, reduce or eliminate) the amount of undercut observed.

14 is a flow chart showing an illustrative embodiment of a workflow 1400 for forming a device, such as but not limited to an appliance or optical component or device, in accordance with the present invention. At 1402, an unpatterned device layer is prepared on the substrate. For example, an unpatterned device layer (eg, a conductive film) is laminated or otherwise deposited onto an electrically insulating surface of the substrate. At 1404, an undercut etch mask is formed, such as by depositing an anti-corrosion layer on the unpatterned device layer and depositing an etch mask over the anti-corrosion material. For example, a liquid primer ink containing an anti-corrosive material is blanket coated onto a substrate, then dried to form an anti-corrosive primer layer, and a liquid etch mask ink is printed on the anti-corrosive primer layer, and then dried. To form an etch mask. The primer layer and the etch mask together form an undercut etch mask. The undercut etch mask may comprise an anti-corrosion layer (such as, for example, anti-corrosion layer 629, 729, 829, 929, 11291229, or 1329) and an etch mask (such as, for example, as discussed in the illustrative examples above). Etching the mask 628, 728, 828, or 928). As noted above, the primer layer and the liquid etch mask ink can interact to form a two component material. As noted above, the primer layer and the liquid etch mask ink can interact to effectively stop or freeze the ink on the surface of the primer. At 1406, a wet etch is performed to remove areas of the unpatterned device layer that are not covered by the etch mask (ie, exposed portions of the unpatterned device layer). The wet etching can be performed for a sufficient time to remove the exposed portions of the unpatterned device layer, leaving a patterned device layer corresponding to the features covered by the etch mask. At 1408, the etch mask is stripped by, for example, immersing the device or stripping the fluid stream to strip the etch mask, which is designed to dissolve and thereby remove the etch mask to expose the resulting patterned device layer on the device. In various further embodiments, the stripping process also removes the corrosion resistant layer under the etch mask.

15 is a flow chart showing in more detail an illustrative embodiment of a workflow 1500 for forming an undercut etch mask such as discussed above in connection with 1404 on a substrate in accordance with the present invention. At 1502, an anti-corrosion layer is formed on the substrate having the unpatterned device layer, such as, for example, anti-corrosion layers 629, 729, 829, 929, 11291229, or 1329. In the embodiment of Figure 15, the corrosion resistant layer is formed as a blanket coating (i.e., an unpatterned layer) over the entire surface of the unpatterned device layer. At 1504, an etch mask, such as an etch mask 628, 728, 828, or 928, is formed over the surface of the anti-corrosion layer in the blanket coating. At 1506, the resist material is exposed or exposed, such as by exposure to a pattern of UV light, as generally discussed in connection with Figures 2A-2C. At 1508, the resist material is developed to form a patterned etch mask, such as, for example, by removing resist material that is not exposed to UV light (in the case of a negative-type program) or exposure to UV light (at The resist material in the case of a positive type of procedure.

16 is a flow chart showing another illustrative embodiment of a workflow 1600 for forming an undercut-resistant etch mask on a substrate in accordance with the present invention. At 1602, a blanket of an anti-corrosion layer (such as, for example, anti-corrosion layer 629, 729, 829, 929, 11291229, or 1329) over the unpatterned device layer is formed over the substrate having the unpatterned device layer. Coating. At 1604, a patterned etch mask (such as, for example, an etch mask 628, 728, 828, or 928) is prepared over the unpatterned anti-corrosion coating.

17 is a flow chart showing another illustrative embodiment of a workflow 1700 for forming a device in accordance with the present invention. At 1702, an unpatterned device layer, such as, for example, but not limited to, a copper film, is laminated to an electrically insulating surface of the substrate. At 1704, a blanket coating of a corrosion resistant layer, such as, for example, corrosion resistant layers 629, 729, 829, 929, 1129, 1229, or 1329, is formed over the copper film. At 1706, an etch mask (such as, for example, a resist) is prepared by printing a liquid resist ink over the blanket coated anti-corrosive material in a desired pattern and then drying the liquid to form an etch mask. Agent mask 628, 728, 828, or 928). At 1708, a spray-type wet etch is performed to etch a copper film region that is not covered by the etch mask material. At 1710, the etch mask is stripped from the remainder of the copper film to expose the formed conductive features. In various embodiments, the corrosion resistant layer is a primer layer, and the liquid resist ink can be applied to the surface in the form of droplets delivered by an inkjet nozzle, and such droplets when in contact with the surface of the primer The movement can be effectively stopped or "frozen" in place (eg, on the order of microseconds), such as but not limited to a chemical reaction triggered by the interaction between the resist ink and the primer layer, such that the ink droplets are on the surface of the primer Further shifting or spreading on the subject is greatly reduced or completely stopped, as described above and in the international publications WO 2016/193978 A2 and WO 2016/025949 A1. In various embodiments, the primer layer and the liquid etch mask ink interact to form a two-component etch mask material.

Figure 18 shows a block diagram of an apparatus 1800 for generating a device in accordance with an embodiment of the present invention. Device 1800 can include a housing 1802. In various exemplary embodiments, the outer casing 1802 can be configured to provide environmental particle filtration, relative humidity control, temperature control, or other program condition control within the processing environment. Apparatus 1800 can include a first substrate transfer mechanism 1804, and a substrate input unit 1806 configured to receive a substrate from first substrate transfer mechanism 1804. The substrate can include an unpatterned device layer, such as substrate 602, 702, 802, or 902 discussed in connection with Figures 6A-9C, and unpatterned device layer 604, 704, 804, or 904. The first deposition module 1808 is configured to deposit a first layer, such as the anti-corrosion layers 629, 729, 829, 929, 1129, 1229 above the unpatterned device layer discussed in connection with Figures 6A-9C and 11-13C, Or 1329, wherein the first deposition module 1808 can include a portion that deposits a first material onto the substrate and a portion that further processes the deposited first material to form the corrosion resistant layer, such as, but not limited to, by drying, curing Or otherwise process the first material. The second deposition module 1812 is configured to deposit an etch mask, such as an etch mask 628, 728, 828, or 928 over the layer of corrosion resistant material discussed in connection with Figures 6A-9D. The second deposition module 1812 can include a portion that deposits a second material onto the substrate and a portion that further processes the deposited second material to form the etch mask, such as, but not limited to, by drying, curing, developing, and exposing , laser direct writing, or otherwise processing the second material. Apparatus 1800 can include a substrate output unit 1820 that provides a substrate to a second substrate transport mechanism (not shown). The first substrate transfer mechanism 1804 can transfer the substrate from a previous processing module or device to the device 1800, and the second substrate transfer mechanism can transfer the substrate to the next processing module or device.

In various exemplary embodiments, first deposition module 1808 and second deposition module 1812 can be configured to deposit material by methods such as inkjet printing, spray coating, lamination, spin coating, or any other deposition method. Including, but not limited to, the deposition methods described above.

In some illustrative embodiments, the apparatus includes a substrate cleaning module 1807 configured to receive a substrate from the substrate input unit 1806, clean the substrate, and transfer the substrate to the first deposition module 1808. In some exemplary embodiments, the first deposition module 1808 and the second deposition module 1812 can be a single module. In some illustrative embodiments, device 1800 includes an etch module 1816 configured to etch material in an unpatterned device layer that is not protected by an etch mask; and a lift-off module 1818 configured to etch the substrate The etch mask is removed from the substrate after the material of the unpatterned device layer.

FIG. 19 shows an illustrative workflow 1900 in accordance with another embodiment of the present invention. At 1902, a primer layer comprising a first reactive component is applied to the unpatterned device layer, such as a metallic surface, such as a copper foil. The primer layer can be an anti-corrosion layer such as the anti-corrosion layer 629, 729, 829, 929, 1129, 1229, or 1329 associated with the specific examples above. At 1904, a two component resist mask is prepared by imaging a liquid resist ink comprising a second composition onto a primer layer, the second composition comprising a second reactive component. The two component material resulting from the interaction of the resist inks can comprise, for example, an etch mask such as 628, 728, 828, or 928 as described in connection with the specific examples above. The second composition can include a second reactive component that is capable of chemically reacting with the first reactive component. In various embodiments, the resist ink can be applied to the surface in the form of droplets delivered by an inkjet nozzle, and such droplets can effectively stop shortly (e.g., on the order of microseconds) upon contact with the surface of the primer. Move or "freeze" in place, such as but not limited to a chemical reaction triggered by the interaction between the resist ink and the primer layer, such that further displacement or diffusion of ink droplets on the surface of the primer is greatly reduced or completely The cessation is as described above and described in International Publication No. WO 2016/193978 A2 and WO 2016/025949 A1. At 1906, the unmasked primer layer portion (ie, the portion of the primer layer that is not covered by the etch mask) is removed before or during the etching process. At 1908, the unmasked portions of the metallic surface are etched to form a patterned device layer, such as the patterned device layer 630, 730, 830, 930, 1130, 1230, or 1330 discussed in connection with the specific examples above. At 1910, the resist mask is removed to expose the patterned device layer.

Examples 1-3

The following comparative examples were conducted to demonstrate that the undercuts obtained using the specific examples of the present invention were reduced as compared to conventional methods that did not use corrosion resistant materials.

In Examples 2 and 3 detailed below, the polyimide component was first applied onto an FR4 copper clad laminate having a copper thickness of 1⁄2 Oz (17 μm) using an Epson stylus 4900 inkjet printer. A resist mask is then applied over the polyimide layer. 10% propylene glycol as a humectant and 1% (w/w) 2-amino-2-methylpropanol as an ion exchanger, 0.3% (w/w) BYK supplied by BYK as a surfactant An aqueous resist composition was prepared by 348 and 2% (w/w) Bayscript BA Cyan as a colorant. The resist solution also included a 24% Joncryl 8085 styrene acrylic resin solution as an anionic resist. In the following description, % (w/w) is a measure of the concentration of the substance based on the weight percentage relative to the weight of the composition. The printed samples were dried at 80 °C. Copper from the unprotected exposed areas is etched away using an etchant bath containing an acidic etching solution. The resist mask was peeled off by immersing the etched plate in a 1% (w/w) aqueous NaOH solution at a temperature of 25 ° C, then washing the FR 4 copper plate with water and air drying at 25 ° C. In Example 1, another sample was prepared without applying an underlayer.

Example 1: A resist pattern was printed on an uncoated copper FR4 board of 1⁄2 Oz (17 μm) copper thickness using an Epson stylus 4900 inkjet printer. Referring to Figure 20, there is shown a photomicrograph of a cross section of a copper wire sample fabricated in accordance with Example 1. 10% propylene glycol as a humectant and 1% (w/w) 2-amino-2-methylpropanol as an ion exchanger, 0.3% (w/w) BYK supplied by BYK as a surfactant An aqueous resist composition was prepared by 348 and 2% (w/w) Bayscript BA Cyan as a colorant. The resist solution also included a 24% Joncryl 8085 styrene acrylic resin solution as an anionic resist reactive component. Drying, etching, and removal of the resist are performed as described above. As can be seen from Figure 20, the slope of the copper sidewall is relatively high. The relevant dimensions of the formed conductive features were measured and the etch factor was calculated to be 1.5.

Example 2: A resist pattern was printed on a copper FR4 plate coated with a polyimide coating. The aqueous polyimine solution was prepared as an aqueous solution of 10% (w/w) LUPASOL G100 (polyethyleneimine having a molecular weight of 5000) supplied by BASF, 10% (w/w) propylene glycol, 10% n-propanol and 0.3%. (w/w) a mixture of TEGO 500 supplied by Evonik Industries. The polyimine solution was applied using an Epson stylus 4900 inkjet printer. The polyimide coating was left to dry at room temperature to give a completely transparent uniform coating having a dry thickness of 0.075 μm covering the entire surface of the panel without crystal formation. The resist composition was printed on the coated copper plate using the methods and materials detailed above. The relevant dimensions of the formed conductive features were measured and the etch factor was calculated to be 2.5.

Example 3: A resist pattern was printed on a copper FR4 plate coated with a polyimide coating. Referring to Figure 21, there is shown a photomicrograph of a cross section of a copper wire copper wire sample fabricated in accordance with Example 3 in accordance with a specific example of the present invention. The polyimide coating was applied to the FR4 board using an Epson stylus 4900 inkjet printer. The polyimine solution was prepared as 10% (w/w) LUPASOL HF (polyethyleneimine having a molecular weight of 25,000) supplied by BASF, 10% (w/w) propylene glycol, 10% n-propanol, and 0.3% ( w/w) An aqueous solution mixture of TEGO 500 supplied by Evonik Industries. The coated panels were allowed to dry at room temperature to give a completely clear uniform coating having a dried layer of a thickness of 0.075 μm covering the entire surface without crystal formation.

A resist composition was prepared as detailed in Example 1. The etching of the unshielded copper and the removal of the resist mask were performed as described in relation to Example 1. As shown in FIG. 21, the slope of the sidewall of the copper wire is much smaller than the slope of the sample prepared without the undercut relief layer as shown in FIG. The relevant dimensions of the formed conductive features were measured and measured and found to have an etch factor of 7.5.

Table 1 below summarizes some of the features of the results of the three embodiments.

The following comparative examples were carried out to demonstrate an improvement in the formation of an etch mask using a primer layer and an inkjet printed resist ink, wherein the composition of the primer layer and the resist ink were in contact with the primer layer. One or more reactions occur to form a two-component etch mask material, and the droplets of resist ink stop moving or freeze rapidly (eg, on the order of microseconds), and then such droplets are diffused and/or displaced decrease very much.

Example 4-12

An exemplary resist composition (described herein as a second composition) was printed on an FR4 copper clad laminate having a thickness of 1/2 Oz, 1/3 Oz, and 1 Oz using an EPson stylus 4900 inkjet printer. In some cases, the immobilized composition (described herein as the first composition) is first coated with copper using an Epson stylus 4900 inkjet printer to form an immobilization layer thereon, selectively resisting printing according to a predetermined pattern. Etchant composition. In the following description, % (w/w) is a measure of the concentration of the substance based on the weight percentage relative to the weight of the composition. Copper from the unprotected-exposed area of the resist was etched away using an etchant bath containing a 42° Baume iron chloride etchant solution [pernix 166] supplied by Amza. Etching was carried out in a Spray Developer S31 supplied by Walter Lemmen GMBH at a temperature of 35 ° C for 3 minutes. The resist mask was peeled off by immersing the etched plate in a 1% (w/w) aqueous NaOH solution at a temperature of 25 ° C, then washing the FR 4 copper plate with water and drying at 25 ° C by air. In some experiments, copper plates were also etched using an industrial etch cell comprising advanced and ultra-high etch cells, manufactured by Universal or Shmidth, containing a copper chloride solution for etching unprotected copper.

Example 4: A resist composition was printed on an uncoated copper FR4 board (comparative data). Prepared with 10% propylene glycol and 1% (w/w) 2-amino-2-methylpropanol, 0.3% (w/w) BYK 348 and 2% (w/w) Bayscript BA Cyan supplied by BYK. Resist composition (second composition). These materials were dissolved in water containing a solution of 24% Joncryl 8085 styrene acrylic resin as an anionic reactive component. The resist composition was printed on an FR4 copper clad laminate having a thickness of 1⁄2 Oz using an Epson stylus 4900 inkjet printer to create a resist mask. The dry resist has a thickness of 5 microns.

The etch mask was visually inspected, and the printed pattern showed very poor print quality, extremely poor edge resolution, broken lines, and severe short circuits between the lines.

Example 5: A resist composition was prepared as detailed in Example 4. The primer or immobilized composition was prepared as 10% (w/w) LUPASOL PR8515 (polyethyleneimine as a cationically reactive component), 10% (w/w) propylene glycol, 10% n-propyl supplied by BASF. An alcohol and an aqueous solution mixture containing 0.3% (w/w) of TEGO 500 (antifoaming substrate wetting additive) supplied by Evonik Industries.

The FR4 copper plate was coated using an Epson stylus 4900 inkjet printer. The coated panels were allowed to dry at room temperature to give a completely clear uniform coating having a dried layer of 0.3 μ thickness covering the entire surface without any crystal formation. The resist composition was printed on a coated copper plate using an Epson stylus 4900 inkjet printer and dried at 80 °C to produce a two component resist mask. The etch mask was visually inspected, which showed better print quality than Example 4, but still had a relatively poor print quality with widened line and line shorts. The etching of the unshielded copper and the removal of the resist mask are performed as detailed in Embodiment 4. The wiring pattern produced after the etching process has the same image as the resist mask having the same widened line and short between lines. It should be noted that for some applications, the print quality exhibited by Example 5 may be sufficient.

Example 6 - A resist composition was prepared as detailed in Example 4. The immobilized composition was prepared as detailed in Example 5, except that 0.3% (w/w) TEGO 500 containing 13% (w/w) concentrated HCl was used instead of 0.3% (w/w) TEGO 500.

The FR4 copper plate was coated with the immobilized composition using an Epson stylus 4900 inkjet printer as detailed in Example 5, and as detailed in Example 5, a coating was formed after drying. Similar to Example 5, the resist composition was inkjet printed on a coated copper plate and dried at 80 ° C to produce a two component resist mask. The resist pattern exhibits high print quality with well-defined thin lines of thickness as low as 2 mm, sharp edges and no breaks. The etching of the unshielded copper and the removal of the resist mask are performed as detailed in Embodiment 4. The wiring pattern produced by the etching and stripping process exhibits a well-defined pattern with thin lines having a width as low as 15 microns, sharp edges and no breaks.

Example 7 - Two-component reaction, the resist composition was printed on a copper surface coated with a reactive cationic composition containing hydrochloric acid (HCl). A resist composition was prepared as detailed in Example 4. The immobilized composition was prepared as an aqueous solution mixture of 10% (w/w) Styleze W-20 (supplied by ISP in 20% aqueous polymer solution), 0.1% BYK 348, and 13% (w/w) concentrated HCl.

The F4F copper plate was covered with an immobilized composition using a Mayer rod to produce a dried layer having a thickness of 0.4 μ. The coated panels were left to dry to give a coating that was completely transparent over the entire copper surface without crystal formation. Similar to Example 5, the resist composition was inkjet printed on a coated copper plate and dried at 80 ° C to produce a two component resist mask.

The resist pattern exhibits high print quality with well-defined and unbroken, thin lines of up to 2 mm. The residue of the immobilized layer not covered by the resist composition was washed by immersing the plate in water at a temperature of 25 ° C for 2 minutes and dried at 80 ° C. The etching of the exposed copper and the removal of the resist mask were performed in detail as in Example 4. The wiring pattern on the board exhibits well-defined thin lines with widths as low as 2 mils, sharp edges and no breaks.

Example 8 - Two-component reaction, the resist composition was printed on a copper surface coated with a reactive cationic composition containing hydrochloric acid (HCl). A resist composition was prepared as detailed in Example 4. Will be fixed

The composition was prepared as an aqueous solution mixture of 10% (w/w) Lupasol HF (supplied by BASF in 56% aqueous polymer solution), 0.1% BYK 348 containing 13% (w/w) concentrated HCl.

The FR4 copper plate was covered with an immobilized composition using a Mayer rod to produce a dried layer having a thickness of 1 μ. The coated panels were left to dry to give a coating that was completely transparent over the entire copper surface without crystal formation. Similar to Example 5, the resist composition was inkjet printed on a coated copper plate and dried at 80 ° C to produce a two component resist mask.

The resist pattern exhibits high print quality with well-defined and as low as 2 mil thin lines with sharp edges and no breaks. The residue of the immobilized layer not covered by the resist composition was washed by immersing the plate in water at a temperature of 25 ° C for 3 minutes and dried at 80 ° C. The etching of the exposed copper and the removal of the resist mask were performed in detail as in Example 4. The wiring pattern on the board exhibits well-defined thin lines with widths as low as 2 mils, sharp edges and no breaks.

Example 9 - Two-component reaction: The resist composition was printed on a copper surface coated with a reactive cationic composition containing hydrochloric acid (HCl). A resist composition was prepared as detailed in Example 5. The immobilized composition was prepared as a 10% (w/w) Lupasol PN50 (supplied by BASF in 49% aqueous polymer solution), 0.1% aqueous solution of BYK 348 containing 13% (w/w) concentrated HCl.

The FR4 copper plate was covered with an immobilized composition using a Mayer rod to produce a dried layer having a thickness of 1 μ. The coated panels were left to dry to give a coating that was completely transparent over the entire copper surface without crystal formation. Similar to Example 5, the resist composition was inkjet printed on a coated copper plate and dried at 80 ° C to produce a two component resist mask.

The resist pattern exhibits high print quality with a well defined clear line and no break lines and fine lines down to 2 mm. The residue of the immobilization layer was washed as detailed in Example 8. The etching of the exposed copper and the removal of the resist mask were performed in detail as in Example 1. The wiring pattern on the board exhibits well-defined thin lines with widths as low as 2 mils, sharp edges and no breaks.

Example 10 - Two-component reaction, the resist composition was printed on a copper surface coated with a reactive composition containing citric acid. A resist composition was prepared as detailed in Example 4. The immobilized composition was prepared as an aqueous solution mixture of 10% (w/w) citric acid, 25% (w/w) propylene glycol containing 0.3% (w/w) of TEGO 500 supplied by Evonik Industries (defoaming substrate run) Wet additive).

The FR4 copper plate was coated with the immobilized composition using an Epson stylus 4900 inkjet printer. The coated panels were allowed to dry at room temperature to give a completely clear uniform coating having a dried layer of 0.3 μ thickness covering the entire surface without crystal formation. Similar to Example 5, the resist composition was inkjet printed on a coated copper plate and dried at 80 ° C to produce a two component resist mask.

The resist pattern exhibits high print quality with well-defined and as low as 2 mil thin lines with sharp edges and no breaks. The etching of the exposed copper and the removal of the resist mask were performed in detail as in Example 4. The wiring pattern on the board exhibits well-defined thin lines with widths as low as 2 mils, sharp edges and no breaks.

Example 11 - Two-component reaction, a coating composition containing a resist composition was prepared as detailed in Example 4. The immobilized composition was prepared into 2.5% (w/w) Zn(NO ₃ ) ₂ , 3.75% (w/w) calcium acetate, 0.2% (w/w) Capstone 51, 5% (w/w) n-propyl. An aqueous solution mixture of alcohol and 5% (w/w) Lupasol FG (supplied by BASF).

The FR4 copper plate was covered with an immobilized composition using a Mayer rod to produce a dried layer having a thickness of 0.5 μ. The coated panels were left to dry to give a coating that was completely transparent over the entire copper surface without crystal formation. Similar to Example 5, the resist composition was inkjet printed on a coated copper plate and dried at 80 ° C to produce a two component resist mask.

Similar to Example 5, the resist composition was inkjet printed on a coated copper plate and dried at 80 ° C to produce a two component resist mask.

The resist pattern exhibits high print quality with well-defined and as low as 2 mil thin lines with sharp edges and no breaks. The etching of the exposed copper and the removal of the resist mask were performed in detail as in Example 4. The wiring pattern on the board exhibits well-defined thin lines with widths as low as 2 mils, sharp edges and no breaks.

Example 12 - Preparation of a resist composition as 8% (w/w) PVA, 24% Joncryl 8085 styrene acrylic resin solution (supplied with 42% aqueous polymer solution) and 1.5% 2-amino 2-a An aqueous solution mixture of propyl alcohol.

The immobilized composition was prepared as follows: 2% (w/w) of Basacid Red 495, 10% (w/w) propylene glycol, 10% n-propanol, 0.3% (w/w) TEG 0500, 10% (w/w) Lupasol G20 (supplied by BASF) containing 12% (w/w) concentrated HCl. The FR4 copper plate was covered with a resist composition using a Mayer rod to produce a dried layer having a thickness of 2.4 μ. The coated panels were left to dry to give a coating that was completely transparent over the entire copper surface without crystal formation. The immobilized composition was ink jet printed on a coated copper plate and dried at 80 ° C to produce a two component resist mask.

Similar to Example 5, the resist composition was inkjet printed on a coated copper plate and dried at 80 ° C to produce a two component resist mask.

The resist pattern exhibits high print quality with well-defined and as low as 2 mil thin lines with sharp edges and no breaks. The residue of the coating not covered by the resist ink was washed by immersing the plate in an aqueous solution of 1% (w/w) NaHCO ₃ for 30 seconds at a temperature of 25 ° C and dried at 80 ° C. The etching of the exposed copper and the removal of the resist mask were performed in detail as in Example 4. The wiring pattern on the board exhibits well-defined thin lines with widths as low as 2 mils, sharp edges and no breaks.

Cationic composition (immobilized reactive component)

Non-limiting examples of the cationically reactive component (immobilized reactive component) may include polydecylamine, such as polyethyleneimine, divalent metal salt, organic or inorganic acid, heteropolymer of vinylpyrrolidone, dimethyl Aminopropyl methacrylamide; methacrylamide propyl laurate dimethyl ammonium chloride, polytetraamine and polyamine in natural form or as an ammonium salt.

The thickness of the dried immobilization layer can be as thin as about 0.01 micron. A typical desired thickness of the dried layer can vary between 0.025 and 5 microns.

The cationic composition (first composition) can include additional components that are tailored to the desired width of the application method and dried layer. The composition may have a viscosity suitable for spray coating or ink jet printing, such as a viscosity of less than 60 centipoise or between 3-20 cP (centipoise) at ambient temperature, respectively. The composition may have a higher viscosity if different application methods are used.

In some embodiments, an acidic solution can be added to the first solution to increase the reactivity of the first layer to the copper layer 320 and its reactivity to the resist or immobilization layer. In some embodiments, the first layer can be further developed, for example, by water prior to the copper etch process. In some embodiments, the applied first layer can be dried prior to applying the second layer. The primary drying layer may primarily comprise a first reactive material. The first layer can be dried using any known drying method.

Some non-limiting examples of the first reactive component (e.g., immobilized component) and the first composition (e.g., immobilized composition, cationic composition) are listed in Table 1.

Anionic composition (resist polymerizable component)

In some embodiments, the second reactive component (eg, a polymerizable component) can be an etch-resistant component (metal-resistant etching solution). The second reactive component can include polyanionic reactive groups such as: acrylates, styrene acrylates; phosphates and sulfonates. The anti-etching ink droplets applied to the first (eg, immobilized) layer may stop due to a chemical reaction between the first reactive material (which includes the polycation) and the second reactive material (which includes the polyanion) Move and fix to the copper surface. Since the immobilization is very rapid (in the microsecond range), the size of the printed pattern is similar to the size of the desired pattern. The compound formed by the reaction of the first reactive material and the second reactive material (both soluble in water) should be insoluble in the copper etching solution.

The second composition may have a viscosity of less than 60 cP, such as 3-20 cP, suitable for ink jet printing at the jetting temperature. The composition may have a higher viscosity if different application methods are used. In some embodiments, the second composition can include no more than 20% (w/w) of reactive components to maintain the desired viscosity. In some embodiments, the polyanionic reactive component (resist polymer) can have a molar weight of a maximum of 5000 when dissolved in the composition (eg, the polymer can have a relatively short chain). In some embodiments, the resist polymer can have a higher molar weight such that the composition is in the form of a polymer emulsion or dispersion. The second reactive component can have a high acid number, for example, having more than 100 reactive anionic groups per gram of polymer. For example, a resist polymer according to a specific example of the present invention may have more than 200, 240, 300 or more reactive anionic groups in each chain.

Some non-limiting examples of the second reactive component (anti-etching component) and the second composition (anti-etching composition, anionic composition) are listed in Table 2.

The description and drawings of the illustrative embodiments are not to be considered as limiting. Variations in the various mechanical, composition, construction, and operation, including equivalents, can be made without departing from the scope of the specification and claims. In some instances, well-known structures and techniques have not been shown or described in detail so as not to obscure the invention. The same numbers in two or more figures indicate the same or similar elements. Furthermore, elements and their associated features that are described in detail with reference to a particular example may be included in any specific embodiments not specifically shown or described. For example, if an element is described in detail with reference to a specific example and the element is not described with reference to the second embodiment, it is claimed that the element is included in the second embodiment.

All numbers and percentages expressing quantities, percentages, or ratios used in the specification and claims are to be understood in all instances as the It has not been modified yet. It is modified by the term "about". Accordingly, the numerical parameters set forth in the following description and the appended claims are approximations, which may vary depending upon the desired properties sought to be obtained. At the very least, and not as an attempt to limit the application of the scope of the application to the scope of the application, each numerical parameter should be interpreted at least in accordance with the number of the number of significant digits shown and by applying the usual rounding technique.

It should be noted that as used in the specification and the appended claims, the singular forms "a", "the" and "the" Clearly and explicitly define a reference object. As used herein, the term "comprise" and its grammatical variations are intended to be non-limiting, such that the description of items in the list does not exclude other similar items that can be substituted or added to the listed items.

Moreover, the terms of the specification are not intended to limit the invention. For example, spatially relative terms can be used - such as "beneath", "below", "lower", "above", "more" "High", "close", and the like, are used to describe one element or feature described in the drawings. In addition to the positions and orientations shown in the drawings, these spatially relative terms are intended to encompass different positions (i.e., positioning) and orientation (i.e., rotational settings) of the device in use or operation. For example, elements in the "following" or "below" other elements or features will be "above" or "above" other elements or features. Thus, the exemplary term "below" can encompass the above and below positions and orientations. Or the device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein are interpreted accordingly.

Further modifications and alternative embodiments will be apparent to those skilled in the art in view of this disclosure. For example, the device and method may include additional components or steps omitted from the drawings and the description for clarity of operation. Accordingly, the description is to be construed as illustrative only and illustrative of the embodiments of the invention. It should be understood that the various specific examples shown and described herein are considered as illustrative. The elements and materials, and the arrangement of such elements and materials may be replaced by those illustrated and described herein. Portions and steps of the workflow and methods may be in alternate order, and some of the features of the present teachings may be utilized independently. It will be apparent to those skilled in the art after benefiting from the description herein. Variations in the elements described herein may be made without departing from the spirit and scope of the present teachings and the scope of the appended claims.

Although various illustrative embodiments herein describe the fabrication of a PCB, those skilled in the art will appreciate that other electrical and optical devices or components fabricated using similar etching and metal or conductive patterning techniques are also encompassed herein. Within the scope of the invention and claims, and the PCB is discussed as a non-limiting illustrative application. Other devices and components that may be fabricated in accordance with the illustrative embodiments herein include, but are not limited to, microchips, electronic displays, microchips, solar cells, and other electronic, optical, or other devices and components.

It is to be understood that the specific examples and specific examples are exemplified herein, and that the structure, dimensions, materials, and methods may be modified without departing from the scope of the present teachings. Other embodiments in accordance with the present invention will be apparent to those skilled in the art in view of this disclosure. It is intended that the specification and examples are considered as illustrative only and that the scope of the claims

1A-1D illustrate cross-sectional and plan views of an apparatus that undergoes a conventional method for forming a patterned layer on a substrate.

2A-2C illustrate cross-sectional and plan views of an apparatus that undergoes another conventional method for forming a patterned layer on a substrate.

3A and 3B show cross-sectional and plan views of an apparatus that undergoes another conventional method for forming a patterned layer on a substrate.

4A-4C illustrate cross-sectional and plan views of an apparatus that undergoes another conventional method for forming a patterned layer on a substrate.

5A-5C illustrate cross-sectional, plan, and perspective views of an apparatus that undergoes another conventional method for forming a patterned layer on a substrate.

6A-6D illustrate cross-sectional and plan views of an apparatus for undergoing a method for forming a patterned layer on a substrate in accordance with an illustrative embodiment of the present invention.

7A-7C illustrate cross-sectional and plan views of an apparatus for undergoing a method for forming a patterned layer on a substrate in accordance with another illustrative embodiment of the present invention.

8A-8D illustrate cross-sectional and plan views of an apparatus for undergoing a method for forming a patterned layer on a substrate in accordance with another illustrative embodiment of the present invention.

9A-9C illustrate cross-sectional and plan views of an apparatus for undergoing a method for forming a patterned layer on a substrate in accordance with another illustrative embodiment of the present invention.

Figure 10 illustrates a cross-sectional view of an apparatus for forming a patterned layer on a substrate during processing in accordance with conventional methods.

Figure 11 shows a cross-sectional view of an apparatus for forming a patterned layer on a substrate during processing, in accordance with an illustrative embodiment of the present invention.

12A is a cross-sectional view of an apparatus for forming a patterned layer on a substrate during processing, in accordance with an illustrative embodiment of the present invention.

Fig. 12B is an enlarged view of a portion in the circle 12B of Fig. 12A.

Figure 13A is a cross-sectional view of an apparatus for forming a patterned layer on a substrate during processing, in accordance with another illustrative embodiment of the present invention.

13B and 13C are enlarged views of portions of circle 13B, C of FIG. 13A, showing characterization of different states in B and C.

14 is a flow chart showing a workflow for forming a patterned layer on a substrate in accordance with an illustrative embodiment of the present invention.

15 is a flow chart showing a workflow for forming a patterned layer on a substrate in accordance with another illustrative embodiment of the present invention.

Figure 16 is a flow chart showing the workflow for forming a patterned layer on a substrate in accordance with another illustrative embodiment of the present invention.

17 is a flow chart showing a workflow for forming a patterned copper layer on a substrate, for example, in the fabrication of a PCB, in accordance with another illustrative embodiment of the present invention.

Figure 18 is a block diagram showing system components for forming a device in accordance with various illustrative embodiments of the present invention.

19 is a flow chart showing a workflow for forming a patterned layer on a substrate in accordance with another illustrative embodiment of the present invention.

Figure 20 is a photomicrograph of a conductive feature formed in accordance with conventional methods.

Figure 21 is a photomicrograph of a conductive feature formed in accordance with an illustrative embodiment of the present invention.

For the sake of simplicity and clarity of the description, elements shown in the drawings are not necessarily drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to the other elements for clarity. Further, element symbols may be repeated in the drawings to indicate corresponding or similar elements, where appropriate.

Claims (27)

 A method of fabricating a device for patterning one or more conductive features, the method comprising: depositing a layer of conductive material over an electrically insulating surface of a substrate; depositing a layer of corrosion resistant material over the layer of conductive material; Depositing a layer of resist material thereon, the resist material layer and the anti-corrosion material layer are patterned to form a two-component etch mask, to obtain a covered portion of the conductive material layer and an exposed portion of the conductive material layer, The covered portion is disposed at a location corresponding to one or more conductive features of the device; performing a wet etch process to remove the exposed portion of the conductive material layer from the electrically insulating substrate; and removing the two-component etch A mask is exposed to expose the remaining conductive material of the covered portion of the layer of conductive material to form one or more conductive features of the device.    The method of claim 1, wherein depositing the layer of corrosion resistant material over the layer of electrically conductive material comprises depositing a polymer over the layer of electrically conductive material.    The method of claim 1, wherein depositing the layer of corrosion resistant material over the layer of electrically conductive material comprises depositing an organic material over the layer of electrically conductive material.    The method of claim 3, wherein the organic material comprises one or more imine groups.    The method of claim 3, wherein the organic material comprises one or more amine groups.    The method of claim 3, wherein the organic material comprises one or more azole groups.    The method of claim 3, wherein the organic material comprises one or more hydrazine groups.    The method of claim 3, wherein the organic material comprises an amino acid.    The method of claim 3, wherein the organic material comprises Schiff Base.    The method of claim 1, further comprising separating a portion of the corrosion resistant material from the two component etch mask during the wet etching process and adsorbing the separated portion of the corrosion resistant material to the two component etch The outer surface of the layer of electrically conductive material under the mask.    The method of claim 1, further comprising protecting the portion of the layer of electrically conductive material adjacent to the two-component etch mask adjacent to the electrically insulating surface of the substrate during the wet etching process The removal of portions of the material layer is not removed.    The method of claim 1, wherein depositing the layer of corrosion resistant material over the layer of electrically conductive material comprises blanket coating depositing the layer of corrosion resistant material over the layer of electrically conductive material.    The method of claim 1, wherein depositing the layer of corrosion resistant material over the layer of electrically conductive material comprises depositing the layer of corrosion resistant material in a pattern corresponding to one or more electrically conductive features.    The method of claim 1, wherein depositing the layer of resist material comprises depositing a blanket coating of the layer of resist material over the layer of corrosion resistant material.    The method of claim 1, wherein depositing the layer of resist material comprises depositing the layer of resist material using at least one of inkjet printing, slit coating, spin coating, or lamination.    The method of claim 1, wherein depositing the layer of corrosion resistant material comprises depositing the layer of corrosion resistant material using at least one of inkjet printing, slot coating, spin coating, or lamination.    The method of claim 1, wherein the corrosion-resistant material layer has a thickness in the range of 5 μm to 40 μm.    An apparatus for fabricating a device patterned with conductive features, the apparatus comprising: a first deposition module configured to deposit a layer of corrosion resistant material over a layer of electrically conductive material over an electrically insulating surface of the substrate; a module configured to deposit a layer of resist material over the layer of corrosion resistant material; and a wet etch module configured to etch the layer of conductive material of the substrate.    The apparatus of claim 18, further comprising a first processing module configured to cure the layer of corrosion resistant material.    The device of claim 18, further comprising a second processing module configured to cure the layer of resist material to form a two-component etch mask.    The device of claim 18, wherein the first deposition module comprises a first inkjet printing module.    The device of claim 18, wherein the second deposition module comprises a second inkjet printing module.    The device of claim 18, further comprising a housing configured to provide processing condition control, the housing housing the first deposition module and the second deposition module.    The device of claim 18, further comprising a stripping module configured to remove the two-component etch mask from the layer of electrically conductive material.    A device patterned with conductive features, comprising: a substrate having an electrically insulating surface; and a conductive feature disposed on the electrically insulating surface, the electrically conductive feature comprising: a height measured in a direction perpendicular to the electrically insulating surface; a first width measured at the electrically insulating surface; and a second width measured at a height along the electrically conductive feature opposite the electrically insulating surface; wherein the first width and the second Half of the difference between the widths divided by the height has a value of at least two.    The device of claim 25, wherein a half of the difference between the first width and the second width divided by the height has a value of at least 5.    The device of claim 25, wherein the height of the conductive feature is 15 μm and the difference between the first width and the second width is less than 6 μm.