Methods for transferring graphene to a substrate and related lithographic stacks and laminates

Abstract

The present application relates to methods for transferring graphene to a substrate and related lithographic stacks and laminates. The methods include at least a method for transferring a graphene-metal bilayer to a substrate to form a laminate thereof. The method can include: applying a first continuous polymer layer to a graphene layer of a graphene-metal bilayer; applying a first discontinuous polymer layer to the first continuous polymer layer; applying a second continuous polymer layer to a metal layer of the graphene-metal bilayer; applying a second discontinuous polymer layer to the second continuous polymer layer; etching the first continuous polymer layer through the first discontinuous polymer layer using a first etchant; laminating the substrate by pressing a face of the graphene layer into a surface of the substrate; etching the second continuous polymer layer through the second discontinuous polymer layer using a second etchant, thereby transferring the graphene-metal bilayer to the substrate to form a laminate.

Description

[0001] priority

[0002] This application claims priority to U.S. Provisional Application No. 63 / 314,219, filed February 25, 2022, which is incorporated herein by reference in its entirety. Technical Field

[0003] This application relates to the field of graphene, and more specifically to methods for transferring graphene to a substrate and related planar stacks and laminates. Background Technology

[0004] Graphene, an allotrope of carbon composed of a single layer of carbon atoms arranged in a two-dimensional honeycomb lattice, possesses mechanical strength (e.g., tensile strength), chemical stability, transparency, carrier mobility, tunable bandgap, and electrical conductivity, making it suitable for a wide range of applications. In fact, many believe that graphene has a significant alternative role in next-generation electronics, enabling the development of smaller and lower-power devices.

[0005] Chemical vapor deposition (CVD) has shown promise as a scalable and economical method for growing graphene on catalysts such as copper and nickel. However, the ability to successfully transfer such graphene onto a variety of substrates has been challenging, often resulting in residual metal or metal etching residues on the graphene or defects (e.g., wrinkles or pores) within the graphene itself. Given the diverse applications of graphene, the ability to cleanly and successfully transfer it onto a variety of substrates remains an important and active area of ​​research. Therefore, new methods, such as those for transferring graphene onto various substrates, are needed to realize the full potential of graphene.

[0006] This article discloses methods for transferring graphene to various substrates, as well as associated lithographic stacks and laminates. Summary of the Invention

[0007] A method for transferring a graphene-metal bilayer to a substrate is disclosed. In some embodiments, the method includes: a first continuous polymer layer application step; a first discontinuous polymer layer application step; a second continuous polymer layer application step; a second discontinuous polymer layer application step; a first etching step; a lamination step; and a second etching step. The first continuous polymer layer application step includes: applying a first continuous polymer layer to the exposed surface of the graphene layer of the graphene-metal bilayer. The first discontinuous polymer layer application step includes: applying a first discontinuous polymer layer to the exposed surface of the first continuous polymer layer, thereby forming a first sacrificial layer of the first continuous polymer layer and the first discontinuous polymer layer. The second continuous polymer layer application step includes: applying a second continuous polymer layer to the exposed surface of the metal layer of the graphene-metal bilayer. The second discontinuous polymer layer application step includes: applying a second discontinuous polymer layer to the exposed surface of the second continuous polymer layer, thereby forming a second sacrificial layer of the second continuous polymer layer and the second discontinuous polymer layer. The first etching step includes: selectively etching the first continuous polymer layer through the first discontinuous polymer layer using a first etchant, thereby removing the first sacrificial layer and exposing the surface of the graphene layer again. The lamination step includes laminating the substrate by pressing the facet of the graphene layer into the surface of the substrate. The second etching step includes selectively etching the second continuous polymer layer through the second discontinuous polymer layer using a second etchant, thereby removing the second sacrificial layer and exposing the facet of the metal layer again. Upon completion of the second etching step, the graphene-metal bilayer is transferred to the substrate.

[0008] In some implementations, the graphene layer is a single layer of graphene.

[0009] In some implementations, the graphene layer is a bilayer of graphene.

[0010] In some implementations, the graphene layer is a multilayer graphene having three or more graphene layers.

[0011] In some embodiments, the first continuous polymer layer application step includes spraying or spin coating the first continuous polymer layer onto the exposed surface of the graphene layer.

[0012] In some embodiments, after the first continuous polymer layer is applied to the exposed surface of the graphene layer in the first continuous polymer layer application step, the first continuous polymer layer is approximately 1-2 μm thick.

[0013] In some implementations, the first continuous polymer layer is polymethyl methacrylate (PMMA).

[0014] In some embodiments, the first discontinuous polymer layer application step includes pressing the first discontinuous polymer layer into the exposed surface of the first continuous polymer layer using heat.

[0015] In some embodiments, the first discontinuous polymer layer is penetrated by an array of perforations therethrough. The perforations allow a first etchant to penetrate through the first discontinuous polymer layer during a first etching step.

[0016] In some embodiments, the second continuous polymer layer application step includes spraying or spin-coating the second continuous polymer layer onto the exposed surface of the metal layer.

[0017] In some embodiments, after the second continuous polymer layer is applied to the exposed surface of the metal layer in the second continuous polymer layer application step, the second continuous polymer layer is approximately 1-2 μm thick.

[0018] In some implementations, the second continuous polymer layer is polyvinyl alcohol (PVA).

[0019] In some embodiments, the second discontinuous polymer layer application step includes pressing the second discontinuous polymer layer into the exposed surface of the second continuous polymer layer using heat.

[0020] In some embodiments, the second discontinuous polymer layer is penetrated by an array of perforations therethrough. The perforations allow a second etchant to penetrate through the second discontinuous polymer layer during a second etching step.

[0021] In some embodiments, each of the first and second discontinuous polymer layers is independently polyimide (PI), polyethylene terephthalate (PET), or polyethylene naphthalate (PEN).

[0022] In some implementations, the first etchant is acetone.

[0023] In some embodiments, the method further includes an adhesive application step. The adhesive application step includes applying an adhesive to the surface of the substrate prior to the lamination step.

[0024] In some implementations, the substrate is a conduit fitting or a Luer connector.

[0025] In some implementations, the substrate is thermoplastic polyurethane (TPU).

[0026] In some implementations, the second etchant is water.

[0027] Another method for transferring a graphene-metal bilayer to a substrate is also disclosed. In some embodiments, the method includes a first continuous polymer layer application step; a first discontinuous polymer layer application step; a second continuous polymer layer application step; a second discontinuous polymer layer application step; a first etching step; a lamination step; and a second etching step. The first continuous polymer layer application step includes: spraying or spin-coating a first continuous polymer layer of PMMA having a thickness of approximately 1-2 μm onto the exposed surface of the graphene layer of the graphene-metal bilayer, including monolayer graphene, bilayer graphene, and more layers of graphene. The first discontinuous polymer layer application step includes: pressing a first discontinuous polymer layer of PI, PET, or PEN having a thickness of approximately 25-50 μm into the exposed surface of the first continuous polymer layer using heat. The first discontinuous polymer layer is penetrated by an array of perforations therethrough. The second continuous polymer layer application step includes: spraying or spin-coating a second continuous polymer layer of PVA having a thickness of approximately 1-2 μm onto the exposed surface of the metal layer of the graphene-metal bilayer. The second discontinuous polymer layer application step includes: pressing a second discontinuous polymer layer, having a thickness of approximately 25-50 μm, of PI, PET, or PEN into the exposed surface of a second continuous polymer layer using heat. The second discontinuous polymer layer is penetrated by an array of perforations therethrough. The first etching step includes: selectively etching the first continuous polymer layer through the perforations of the first discontinuous polymer layer using a first etchant of acetone to expose the surface of the graphene layer again. The lamination step includes: laminating a TPU substrate by pressing the surface of the graphene layer into the surface of a substrate. The surface of the substrate optionally includes an adhesive applied thereto. The second etching step includes: selectively etching the second continuous polymer layer through the perforations of the second discontinuous polymer layer using a second etchant of water to expose the surface of the metal layer again. Upon completion of the second etching step, a graphene-metal bilayer is transferred to the substrate.

[0028] In some implementations, the substrate is a conduit fitting or a Luer connector.

[0029] A method for transferring a graphene layer to a substrate is also disclosed. In some embodiments, the method includes a first continuous polymer layer application step; a first discontinuous polymer layer application step; a second continuous polymer layer application step; a second discontinuous polymer layer application step; a first etching step; a lamination step; and a second etching step. The first continuous polymer layer application step includes applying a first continuous polymer layer to a first exposed surface of the graphene layer. The first discontinuous polymer layer application step includes applying a first discontinuous polymer layer to the exposed surface of the first continuous polymer layer, thereby forming a first continuous polymer layer and a first sacrificial layer of the first discontinuous polymer layer. The second continuous polymer layer application step includes applying a second continuous polymer layer to a second exposed surface of the graphene layer. The second discontinuous polymer layer application step includes applying a second discontinuous polymer layer to the exposed surface of the second continuous polymer layer, thereby forming a second continuous polymer layer and a second discontinuous polymer layer of the second sacrificial layer. The first etching step includes selectively etching the first continuous polymer layer through the first discontinuous polymer layer using a first etchant, thereby removing the first sacrificial layer and exposing the first surface of the graphene layer again. The lamination step includes laminating the substrate by pressing a first side of the graphene layer into the surface of the substrate. The second etching step includes selectively etching a second continuous polymer layer through a second discontinuous polymer layer using a second etchant, thereby removing the second sacrificial layer and exposing the second side of the graphene layer again. Upon completion of the second etching step, the graphene layer is transferred to the substrate.

[0030] A laminate is also disclosed, in some embodiments of which the laminate includes a substrate comprising one or more polymer layers and a graphene-metal bilayer laminated on at least a portion of the substrate.

[0031] In some implementations, the substrate has two dimensions.

[0032] In some implementations, the substrate is a sheet comprising one or more polymer layers.

[0033] In some implementations, the substrate has three dimensions.

[0034] In some embodiments, the substrate is a medical device or part of a medical device that includes the one or more polymer layers.

[0035] In some implementations, the substrate is a Luer connector for the conduit.

[0036] In some implementations, the substrate is the conduit fitting of the conduit.

[0037] In some implementations, the graphene-metal bilayer is patterned into one or more electronic devices.

[0038] In some implementations, the one or more electronic devices include at least one single-material graphene thermocouple as a temperature sensor.

[0039] In some implementations, the polymer is TPU.

[0040] In some embodiments, the laminate also includes an adhesive layer between the substrate and the graphene-metal bilayer.

[0041] In some implementations, the graphene-metal bilayer includes a metal layer on top of a graphene layer.

[0042] In some implementations, the metal layer is formed of copper or nickel.

[0043] In some implementations, the graphene layer is a single layer of graphene.

[0044] In some implementations, the graphene layer is a bilayer of graphene.

[0045] In some implementations, the graphene layer is a multilayer graphene having three or more graphene layers.

[0046] A planar stack for transferring a graphene-metal bilayer to a substrate is also disclosed. In some embodiments, the planar stack includes a graphene-metal bilayer, a first sacrificial layer on the graphene-metal bilayer, and a second sacrificial layer beneath the graphene-metal bilayer. The first sacrificial layer includes a first continuous polymer layer on the graphene layer of the graphene-metal bilayer and a first discontinuous polymer layer on the first continuous polymer layer. The second sacrificial layer includes a second continuous polymer layer beneath the metal layer of the graphene-metal bilayer and a second discontinuous polymer layer beneath the second continuous polymer layer. The first continuous polymer layer and the second continuous polymer layer, made of two different materials, exhibit specific instabilities between at least two different etchants.

[0047] In some implementations, the graphene layer is a single layer of graphene.

[0048] In some implementations, the graphene layer is a bilayer of graphene.

[0049] In some implementations, the graphene layer is a multilayer graphene having three or more graphene layers.

[0050] In some implementations, the first continuous polymer layer is approximately 1-2 μm thick.

[0051] In some implementations, the first continuous polymer layer is PMMA.

[0052] In some embodiments, a first discontinuous polymer layer is penetrated by an array of perforations therethrough. The perforation array allows a first etchant of at least two etchants to penetrate through the first discontinuous polymer to selectively etch the first continuous polymer layer.

[0053] In some implementations, the first etchant is acetone.

[0054] In some implementations, the second continuous polymer layer is approximately 1-2 μm thick.

[0055] In some implementations, the second continuous polymer layer is PVA.

[0056] In some embodiments, the second discontinuous polymer layer is penetrated by an array of perforations therethrough. The perforation array allows a second etchant of at least two etchants to penetrate through the second discontinuous polymer to selectively etch the second continuous polymer layer.

[0057] In some implementations, the second etchant is water.

[0058] In some embodiments, each of the first and second discontinuous polymer layers is independently PI, PET, or PEN.

[0059] These and other features of the concept provided herein will become more apparent to those skilled in the art in view of the accompanying drawings and the following description, which describe in more detail specific embodiments of such a concept. Attached Figure Description

[0060] Figure 1 A method for transferring graphene to a substrate according to some embodiments is shown.

[0061] Figure 2 A laminated component, which is part of a conduit having conduit fittings, is shown according to some embodiments, having a graphene-metal bilayer laminated thereon.

[0062] Figure 3 Another laminate, which is part of a conduit with conduit fittings, is shown according to some embodiments, having a graphene-metal bilayer patterned as an electronic device. Detailed Implementation

[0063] Before disclosing some specific embodiments in more detail, it should be understood that the specific embodiments disclosed herein do not limit the scope of the concepts provided herein. It should also be understood that the specific embodiments disclosed herein may have features that allow them to be readily separable from the specific embodiments and optionally combined with or substituted for features of any of the many other embodiments disclosed herein.

[0064] Regarding the terminology used herein, it should also be understood that these terms are for descriptive purposes and do not limit the scope of the concepts presented herein. Ordinal numbers (e.g., first, second, third, etc.) are generally used to distinguish or identify different features or steps within a set of features or steps and do not provide for any order or numerical limitation. For example, the features or steps “first,” “second,” and “third” do not necessarily have to appear in that order, and a particular embodiment including such a feature or step does not necessarily have to be limited to three features or steps. Furthermore, unless otherwise indicated, any of the foregoing features or steps may further include one or more features or steps. For convenience, labels such as “left,” “right,” “top,” “bottom,” “front,” “back,” etc., are used, and these labels are not intended to suggest, for example, any particular fixed position, orientation, or direction. Rather, such labels are used to reflect, for example, relative position, orientation, or direction. The singular forms “a,” “an,” and “the” include plural references unless the context clearly indicates otherwise.

[0065] The terms "proximal," "proximal portion," or "proximal segment" for example, referring to a catheter, include the portion or segment of the catheter intended to be close to the clinician when used with the patient. Similarly, the term "proximal length" for example, referring to a catheter, includes the length of the catheter intended to be close to the clinician when used with the patient. For example, the term "proximal end" of a catheter includes the end of the catheter intended to be close to the clinician when used with the patient. A proximal portion, proximal segment, or proximal length of a catheter may include the proximal end of the catheter; however, a proximal portion, proximal segment, or proximal length of a catheter does not necessarily include the proximal end of the catheter. That is, unless the context otherwise suggests, a proximal portion, proximal segment, or proximal length of a catheter is not the distal portion or distal length of the catheter.

[0066] The terms "distal," "distal portion," or "distal segment" for a catheter, for example, include the portion or segment of the catheter intended to be close to or within the patient when the catheter is used. Similarly, the term "distal length" for a catheter, for example, includes the length of the catheter intended to be close to or within the patient when the catheter is used. For instance, the term "distal end" for a catheter includes the end of the catheter intended to be close to or within the patient when the catheter is used. A distal portion, distal segment, or distal length of a catheter may include the distal end of the catheter; however, a distal portion, distal segment, or distal length of a catheter does not necessarily include the distal end of the catheter. That is, unless the context otherwise suggests, a distal portion, distal segment, or distal length of a catheter is not the distal portion or distal length of the catheter.

[0067] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art.

[0068] As mentioned above, CVD has shown promise as a scalable and economical method for growing graphene on catalysts such as copper and nickel. However, the ability to successfully transfer such graphene onto a variety of substrates has been challenging, often resulting in residual metal or metal etching residues on the graphene or defects (e.g., wrinkles or pores) within the graphene itself. Given the diverse applications of graphene, the ability to cleanly and successfully transfer graphene onto a variety of substrates remains an important and active area of ​​research. Therefore, new methods, such as those for transferring graphene onto various substrates, are needed to realize the full potential of graphene.

[0069] Methods for transferring graphene to a substrate, and associated planar stacks and laminates, are disclosed. For example, one method involves transferring a graphene-metal bilayer to a substrate to form a laminate thereon. This method may include: applying a first continuous polymer layer to a graphene layer of the graphene-metal bilayer; applying a first discontinuous polymer layer to the first continuous polymer layer; applying a second continuous polymer layer to a metal layer of the graphene-metal bilayer; applying a second discontinuous polymer layer to the second continuous polymer layer; etching the first continuous polymer layer through the first discontinuous polymer layer using a first etchant; laminating the substrate by pressing the facets of the graphene layer into the surface of the substrate; and etching the second continuous polymer layer through the second discontinuous polymer layer using a second etchant, thereby transferring the graphene-metal bilayer to the substrate to form a laminate.

[0070] Figure 1 A method for transferring graphene to a substrate 100 according to some embodiments is illustrated. It is noteworthy that the method may include transferring graphene from... Figure 1 One or more steps selected from those shown or described below. Additionally, while many possible steps of the method for transferring graphene to substrate 100 are named herein, it should be understood that the method may include steps described herein but not named. Finally, unless otherwise indicated, any of the many possible steps of the method for transferring graphene to substrate 100 named or described herein may further include one or more steps (e.g., sub-steps).

[0071] Although not shown, this method can begin with a graphene growth step. The graphene growth step involves growing a graphene layer 102 on a metal layer 104 via CVD or the like to form a graphene-metal bilayer 106. However, the metal layer 104 on which the graphene layer 102 is grown can be the same as or different from the metal layer 104 described below, depending on whether one or more additional steps are performed to effectively exchange the metal layer. For example, in the graphene growth step, the graphene layer 102 can be grown on a nickel or copper layer serving as the metal layer 104, and the nickel or copper layer can actually be exchanged with a palladium or gold layer, resulting in the metal layer 104 described below. That is, the metal layer 104 on which the graphene layer 102 is grown can alternatively be removed entirely in one or more additional steps, thereby replacing the graphene-metal bilayer 106 described below solely with the graphene layer 102. Regardless, when present, the metal layer 104 may be formed of gold, silver, palladium, copper, or nickel; however, copper is generally preferred for use in one or more electronic devices described below. The graphene layer 102 grown on the metal layer 104 may be a single-layer graphene, a bilayer graphene, or a multilayer graphene comprising three or more graphene layers.

[0072] Although not shown, the method may include a first continuous polymer layer application step. The first continuous polymer layer application step includes applying a first continuous polymer layer 108 (e.g., polymethyl methacrylate [PMMA]) to the exposed surface of the graphene layer 102 of the graphene-metal bilayer 106, for example, by spraying or spin-coating the first continuous polymer layer 108 onto the exposed surface of the graphene layer 102 until it is approximately 1-2 μm thick, to form a planar stack of the graphene-metal bilayer 106 and the first continuous polymer layer 108. It is noteworthy that the first continuous polymer layer application step can be combined with... Figure 1 The second continuous polymer layer application step (step A) is shown to start from the opposite side of the graphene-metal bilayer 106.

[0073] Although not shown, the method may include a first discontinuous polymer layer application step, optionally after a first perforation step, to form a first discontinuous polymer layer 110. The first discontinuous polymer layer application step includes applying a first discontinuous polymer layer 110 (e.g., approximately 25-50 μm of polyimide [PI], polyethylene terephthalate [PET], or polyethylene naphthalate [PEN], but independent of a second discontinuous polymer layer 120) to an exposed surface of a first continuous polymer layer 108, for example, by pressing the first discontinuous polymer layer 110 into the exposed surface of the first continuous polymer layer 108 with heat to form a planar stack 112 of a graphene-metal bilayer 106 and a first sacrificial layer 114, wherein the first sacrificial layer 114 comprises the first continuous polymer layer 108 and the first discontinuous polymer layer 110. The pressure and temperature applied during the first discontinuous polymer layer application step should be sufficient to bond the graphene-metal bilayer 106 and the first sacrificial layer 114 with sufficient integrity to hold the planar stack 112 together for subsequent roll-to-roll or batch processing. It is worth noting that the first discontinuous polymer layer application step is capable of... Figure 1 The second discontinuous polymer layer application step (step B) is shown to begin from the opposite side of the graphene-metal bilayer 106 having a first continuous polymer layer 108 thereon.

[0074] As shown in the figure, the method may include a second continuous polymer layer application step (step A). ​​The second continuous polymer layer application step includes applying a second continuous polymer layer 116 (e.g., polyvinyl alcohol [PVA]) to the exposed surface of the metal layer 104 of the graphene-metal bilayer 106, for example, by spraying or spin-coating the second continuous polymer layer 116 onto the exposed surface of the graphene layer 102 until it is approximately 1-2 μm thick, to form a planar stack 118 of the graphene-metal bilayer 106, the first sacrificial layer 114, and the second continuous polymer layer 116. It is noteworthy that the first continuous polymer layer 108 and the second continuous polymer layer 116 are made of two different materials, such as PMMA and PVA, which have exclusive instabilities between at least two different etchants (e.g., acetone and water described below).

[0075] As shown in the figure, the method may include a second discontinuous polymer layer application step (step B), optionally following the second perforation step, to form a second discontinuous polymer layer 120. The second discontinuous polymer layer application step (step B) includes applying the second discontinuous polymer layer 120 (e.g., approximately 25-50 μm of PI, PET, or PEN, but independent of the first discontinuous polymer layer 110) to the exposed surface of the second continuous polymer layer 116, for example, by pressing the second discontinuous polymer layer 120 into the exposed surface of the second continuous polymer layer 116 with heat, to form a planar stack 122 of graphene-metal bilayer 106, a first sacrificial layer 114, and a second sacrificial layer 124, wherein the second sacrificial layer 124 comprises the second continuous polymer layer 116 and the second discontinuous polymer layer 120. In practice, the planar stack 122 includes the graphene-metal bilayer 106, the first sacrificial layer 114 on the graphene-metal bilayer 106, and the second sacrificial layer 124 beneath the graphene-metal bilayer 106. The pressure and temperature applied during the second discontinuous polymer layer application step should be sufficient to bond the graphene-metal bilayer 106 and the second sacrificial layer 124 with sufficient integrity to hold the flat stack 122 together for subsequent roll-to-roll or batch processing.

[0076] As shown in the figure, the method may include a first etching step (step C). The first etching step (step C) involves selectively etching a first continuous polymer layer 108 through a first discontinuous polymer layer 110 using a first etchant (e.g., acetone at approximately 40-50°C), thereby removing the first sacrificial layer 114 and exposing the face of the graphene layer 102 again to form a planar stack 126 of a graphene-metal bilayer 106 and a second sacrificial layer 124. Notably, the first discontinuous polymer layer 110 is permeable to the first etchant. In practice, the first discontinuous polymer layer 110 is perforated by an array of regular or irregular perforations 128, which may perforate at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% of the first discontinuous polymer layer 110. For example, at least 33% of the first discontinuous polymer layer 110 may be perforated within the first discontinuous polymer layer 110. The array of perforations 128 allows the first etchant to penetrate through the first discontinuous polymer layer 110 during the first etching step to selectively etch the first continuous polymer layer 108 on the second continuous polymer layer 116 or any other layer present.

[0077] Although not shown, the method may include an adhesive application step. The adhesive application step includes applying adhesive 130 to the surface of substrate 100 prior to the lamination step described below. It is worth noting that, depending on the surface chemistry between the face of graphene layer 102 and the surface of substrate 100, the laminate 132 described below may or may not benefit from adhesive 130.

[0078] As shown in the figure, the method may include a lamination step (step D). The lamination step (step D) includes laminating at least a portion of the substrate 100 by pressing the facet of the graphene layer 102 into the surface of the substrate 100 or a portion thereof, optionally using an adhesive 130 to form a laminate 132 of the substrate 100 and the graphene-metal bilayer 106, having the remaining portion of the planar stack 126 thereon, i.e., the second sacrificial layer 124. Notably, the substrate 100 may have two dimensions of a two-dimensional substrate, such as a sheet comprising one or more polymer layers 134, the polymer being, for example, thermoplastic polyurethane (TPU). Alternatively, the substrate 100 may have three dimensions for a three-dimensional substrate, such as a medical device (e.g., catheter, probe, cannula, syringe, etc.) comprising the aforementioned polymer layers 134. The three-dimensional substrate or portion thereof laminated with the graphene-metal bilayer 106 may be non-planar, for example, curved. In fact, the portion of the three-dimensional substrate laminated with the graphene-metal bilayer 106 can be bent like the conduit fitting 140 of the conduit 139 described below.

[0079] As shown in the figure, the method may include a second etching step (step E). The second etching step (step E) involves selectively etching the second continuous polymer layer 116 through the second discontinuous polymer layer 120 using a second etchant (e.g., water or deionized water at approximately 60-80°C), thereby removing the second sacrificial layer 124 and exposing the surface of the metal layer 104 again to form a laminate 136 of the substrate 100 and the graphene-metal bilayer 106. Notably, the second discontinuous polymer layer 120 is permeable to the second etchant. In practice, the second discontinuous polymer layer 120 is perforated by an array of regular or irregular perforations 138, which may perforate at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% of the second discontinuous polymer layer 120. For example, at least 33% of the second discontinuous polymer layer 120 may be perforated within the second discontinuous polymer layer 120. The array of perforations 138 allows the second etchant to penetrate through the second discontinuous polymer layer 120 during the second etching step, in order to selectively etch the second continuous polymer layer 116 on any other layers present.

[0080] It is worth noting that the aforementioned method of transferring graphene to substrate 100 is advantageously capable of large-scale production, for example in roll-to-roll or batch processing.

[0081] During the second etching step of the method for transferring graphene to substrate 100 described above, the graphene-metal bilayer 106 is successfully transferred to at least a portion of substrate 100, thereby forming a laminate 136. As described above, substrate 100 can be a two-dimensional substrate (e.g., a sheet). The laminate obtained from such a two-dimensional substrate includes a graphene-metal bilayer 106 laminated on at least a portion of substrate 100 for a two-dimensional laminate. As described above, substrate 100 can alternatively be a three-dimensional substrate (e.g., a medical device). The laminate obtained from such a three-dimensional substrate includes a graphene-metal bilayer 106 laminated on at least a portion of substrate 100 for a three-dimensional laminate.

[0082] Figure 2 and Figure 3 A laminate 136, which is part of a conduit 139 having a conduit fitting 140, is shown according to some embodiments, having a graphene-metal bilayer 106 laminated thereon.

[0083] As shown in the figure, the laminate 136 includes a portion of a conduit 139 laminated with a graphene-metal bilayer 106. Although Figure 2 The portion of the conduit 139 laminated with the graphene-metal bilayer 106 shown is at least the proximal portion of the conduit fitting 140 (up to the entire conduit fitting 140), but the portion of the conduit 139 laminated with the graphene-metal bilayer 106 may additionally or alternatively be a hub 142, one or more extension legs 144, or one or more Luer connectors 146. Figure 3 As shown, the conduit fitting 140 can be advantageously laminated in at least its distal portion to include one or more electronic devices. In practice, the graphene-metal bilayer 106 can be patterned in one or more patterning steps before or after the lamination step, which in turn can include various masking and etching steps to produce one or more electronic devices. The one or more electronic devices can include at least one single-material graphene thermocouple 148 as a temperature sensor. Such a thermocouple can be similar to those described in the following literature: Harzheim, A., F., Gotsmann, B., van der Zant, H., & Gehring, P. (2020). Single-Material Graphene Thermocouples. Advanced Functional Materials, 30(22), 2000574. Thermocouple 148 includes: for example, a graphene layer 102 patterned as a narrower leg 150 and a wider leg 152 having different Seebeck coefficients, coupled together by a thermoelectric junction between them; and a metal layer 104 patterned as an electrical contact 154 and leads extending therefrom.

[0084] While certain specific embodiments have been disclosed herein, and while these specific embodiments have been disclosed in considerable detail, they are not intended to limit the scope of the concepts provided herein. Other adaptations and / or modifications will be apparent to those skilled in the art, and these adaptations and / or modifications are also covered in a broader sense. Therefore, changes may be made to the specific embodiments disclosed herein without departing from the scope of the concepts provided herein.

Claims

1. A method for transferring a graphene-metal bilayer to a substrate, characterized in that, include: A first continuous polymer layer is applied to the exposed surface of the graphene layer of the graphene-metal bilayer; A first discontinuous polymer layer is applied to the exposed surface of the first continuous polymer layer to form a first sacrificial layer of the first continuous polymer layer and the first discontinuous polymer layer. A second continuous polymer layer is applied to the exposed surface of the metal layer of the graphene-metal bilayer; A second discontinuous polymer layer is applied to the exposed surface of the second continuous polymer layer to form a second sacrificial layer of the second continuous polymer layer and the second discontinuous polymer layer; Using a first etchant, the first continuous polymer layer is selectively etched through the first discontinuous polymer layer to remove the first sacrificial layer and expose the face of the graphene layer again; The substrate is laminated by pressing the surface of the graphene layer into the surface of the substrate; and Using a second etchant, the second continuous polymer layer is selectively etched through the second discontinuous polymer layer to remove the second sacrificial layer, thereby exposing the surface of the metal layer again and transferring the graphene-metal bilayer to the substrate.

2. The method according to claim 1, characterized in that, The graphene layer is a single layer of graphene.

3. The method according to claim 1, characterized in that, The graphene layer is a bilayer graphene.

4. The method according to claim 1, characterized in that, The graphene layer is a multilayer graphene having three or more graphene layers.

5. The method according to claim 1, characterized in that, Applying the first continuous polymer layer to the exposed surface of the graphene layer includes: spraying or spin-coating the first continuous polymer layer onto the exposed surface of the graphene layer.

6. The method according to claim 1, characterized in that, After the first continuous polymer layer is applied to the exposed surface of the graphene layer, the first continuous polymer layer is 1-2 μm thick.

7. The method according to claim 1, characterized in that, The first continuous polymer layer is polymethyl methacrylate.

8. The method according to claim 1, characterized in that, Applying the first discontinuous polymer layer to the exposed surface of the first continuous polymer layer includes: pressing the first discontinuous polymer layer into the exposed surface of the first continuous polymer layer with heat.

9. The method according to claim 1, characterized in that, The first discontinuous polymer layer is penetrated by an array of perforations therethrough, thereby allowing the first etchant to penetrate through the first discontinuous polymer layer during selective etching of the first continuous polymer layer.

10. The method according to claim 1, characterized in that, Applying the second continuous polymer layer to the exposed surface of the metal layer includes spraying or spin-coating the second continuous polymer layer onto the exposed surface of the metal layer.

11. The method according to claim 1, characterized in that, After the second continuous polymer layer is applied to the exposed surface of the metal layer, the second continuous polymer layer is 1-2 μm thick.

12. The method according to claim 1, characterized in that, The second continuous polymer layer is polyvinyl alcohol.

13. The method according to claim 1, characterized in that, Applying the second discontinuous polymer layer to the exposed surface of the second continuous polymer layer includes: pressing the second discontinuous polymer layer into the exposed surface of the second continuous polymer layer with heat.

14. The method according to claim 1, characterized in that, The second discontinuous polymer layer is penetrated by an array of perforations therethrough, thereby allowing the second etchant to penetrate through the second discontinuous polymer layer during selective etching of the second continuous polymer layer.

15. The method according to claim 1, characterized in that, Each of the first and second discontinuous polymer layers is independently a polyimide, polyethylene terephthalate, or polyethylene naphthalate.

16. The method according to claim 1, characterized in that, The first etchant is acetone.

17. The method according to claim 1, characterized in that, Also includes: Before laminating the substrate, an adhesive is applied to the surface of the substrate.

18. The method according to claim 1, characterized in that, The substrate is a conduit fitting or a Luer connector.

19. The method according to claim 1, characterized in that, The substrate is thermoplastic polyurethane.

20. The method according to claim 1, characterized in that, The second etchant is water.

21. A method for transferring a graphene-metal bilayer to a substrate, characterized in that, include: A first continuous polymer layer of polymethyl methacrylate with a thickness of 1-2 μm is sprayed or spin-coated onto the exposed surface of the graphene layer of the graphene-metal bilayer, which is a single-layer graphene, a double-layer graphene, or a multi-layer graphene. A first discontinuous polymer layer of polyimide, polyethylene terephthalate, or polyethylene naphthalate with a thickness of 25-50 μm is pressed into the exposed surface of the first continuous polymer layer by heat, and the first discontinuous polymer layer is penetrated by a perforated array therethrough. A second continuous polymer layer of polyvinyl alcohol with a thickness of 1-2 μm is sprayed or spin-coated onto the exposed surface of the metal layer of the graphene-metal bilayer; A second discontinuous polymer layer of polyimide, polyethylene terephthalate, or polyethylene naphthalate with a thickness of 25-50 μm is pressed into the exposed surface of the second continuous polymer layer by heat, and the second discontinuous polymer layer is penetrated by a perforated array therethrough. Using acetone as a first etchant, the first continuous polymer layer is selectively etched through perforations in the first discontinuous polymer layer to expose the facet of the graphene layer again. A thermoplastic polyurethane substrate is laminated by pressing the surface of the graphene layer into the surface of the substrate, wherein the surface of the substrate optionally includes an adhesive applied thereon. and Using a second etchant of water, the second continuous polymer layer is selectively etched through perforations in the second discontinuous polymer layer to expose the face of the metal layer again, thereby transferring the graphene-metal bilayer to the substrate.

22. The method according to claim 21, characterized in that, The substrate is a conduit fitting or a Luer connector.

23. A method for transferring a graphene layer to a substrate, characterized in that, include: A first continuous polymer layer is applied to the first exposed surface of the graphene layer; A first discontinuous polymer layer is applied to the exposed surface of the first continuous polymer layer to form a first sacrificial layer of the first continuous polymer layer and the first discontinuous polymer layer. A second continuous polymer layer is applied to the second exposed surface of the graphene layer; A second discontinuous polymer layer is applied to the exposed surface of the second continuous polymer layer to form a second sacrificial layer of the second continuous polymer layer and the second discontinuous polymer layer; Using a first etchant, the first continuous polymer layer is selectively etched through the first discontinuous polymer layer to remove the first sacrificial layer and expose the first exposed surface of the graphene layer again; The substrate is laminated by pressing the first exposed surface of the graphene layer into the surface of the substrate; and Using a second etchant, the second continuous polymer layer is selectively etched through the second discontinuous polymer layer to remove the second sacrificial layer, thereby exposing the second exposed surface of the graphene layer again, and transferring the graphene layer to the substrate.

24. A planar stack for transferring a graphene-metal bilayer to a substrate, characterized in that, include: Graphene-metal bilayer; A first sacrificial layer, located on the graphene-metal bilayer, comprises: A first continuous polymer layer, which is located on the graphene layer of the graphene-metal bilayer; and A first discontinuous polymer layer, which is located on the first continuous polymer layer; and A second sacrificial layer, located beneath the graphene-metal bilayer, comprises: A second continuous polymer layer, located beneath the metal layer of the graphene-metal bilayer, and the first and second continuous polymer layers, made of two different materials, exhibit specific instabilities between at least two different etchants; and A second discontinuous polymer layer is located beneath the second continuous polymer layer.

25. The flat stacked component according to claim 24, characterized in that, The graphene layer is a single layer of graphene.

26. The planar stacked component according to claim 24, characterized in that, The graphene layer is a bilayer graphene.

27. The planar stacked component according to claim 24, characterized in that, The graphene layer is a multilayer graphene having three or more graphene layers.

28. The planar stacked component according to claim 24, characterized in that, The first continuous polymer layer is 1-2 μm thick.

29. The planar stacked component according to claim 24, characterized in that, The first continuous polymer layer is polymethyl methacrylate.

30. The planar stacked component according to claim 24, characterized in that, The first discontinuous polymer layer is penetrated by an array of perforations therethrough, thereby allowing the first of the at least two etchants to penetrate through the first discontinuous polymer in order to selectively etch the first continuous polymer layer.

31. The planar stacked component according to claim 30, characterized in that, The first etchant is acetone.

32. The planar stacked component according to claim 24, characterized in that, The second continuous polymer layer is 1-2 μm thick.

33. The flat stacked component according to claim 24, characterized in that, The second continuous polymer layer is polyvinyl alcohol.

34. The planar stacked component according to claim 24, characterized in that, The second discontinuous polymer layer is penetrated by an array of perforations therethrough, thereby allowing a second etchant of the at least two different etchants to penetrate through the second discontinuous polymer in order to selectively etch the second continuous polymer layer.

35. The planar stacked component according to claim 34, characterized in that, The second etchant is water.

36. The planar stacked component according to claim 24, characterized in that, Each of the first and second discontinuous polymer layers is independently a polyimide, polyethylene terephthalate, or polyethylene naphthalate.

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