CN114385018A

CN114385018A - Contact structure, electronic device, and method of manufacturing contact structure

Info

Publication number: CN114385018A
Application number: CN202011123507.8A
Authority: CN
Inventors: 林志强; 江一敏; 陈盛杰; 李婷婷; 王喜照; 母利伟; 吴珊瑀; 陈志民; 郭昭辉
Original assignee: TPK Advanced Solutions Inc
Current assignee: TPK Advanced Solutions Inc
Priority date: 2020-10-20
Filing date: 2020-10-20
Publication date: 2022-04-22

Abstract

A contact structure, an electronic device, and a method of manufacturing a contact structure are provided. The contact structure includes: the composite coating comprises a substrate, a copper layer, an organic composite protective layer and a nano silver layer. The copper layer is disposed over the substrate. The organic composite type protective layer is arranged on the copper layer and used for preventing the copper layer from being oxidized, wherein the organic composite type protective layer forms a monomolecular adsorption layer on the surface of the copper layer. The nano silver layer is arranged on the organic compound protective layer. A method of fabricating a contact structure is also provided. The organic compound type protection layer is arranged on the copper layer, so that the phenomenon that the copper layer in the contact structure is oxidized and discolored in the subsequent processing procedure is prevented.

Description

Contact structure, electronic device, and method of manufacturing contact structure

Technical Field

The present disclosure relates to a contact structure, an electronic device and a method for fabricating the same, and more particularly, to a contact structure having a copper layer and a nano-silver layer stacked thereon, an electronic device and a method for fabricating the same.

Background

In the prior art, in some electronic devices (e.g., touch panels), the material of the transmission line is usually a copper material layer at the contact area where the touch electrode meets the transmission line, and the touch electrode uses a nano-silver material layer. However, in the fabrication of devices including such contact regions, in the photolithography process, since the potential difference between the copper and silver metals exists in the stripping solution (e.g., tetramethylammonium hydroxide (TMAH) solution), an oxidation-reduction reaction occurs, which results in oxidation and discoloration of the copper material layer.

FIG. 1A is a schematic diagram of a conventional apparatus 10 including a contact region 20 prior to stripping liquid treatment in a photolithography process. The device 10 includes a substrate 12, a copper layer 14 over the substrate 12, and a nano-silver layer 16 over the substrate 12 and partially covering the copper layer 14. FIG. 1B is a schematic view of the apparatus of FIG. 1A after stripping liquid treatment in a yellow light process, wherein discoloration of the copper layer 14' in the contact region 20 occurs. Fig. 1C is a partial top view of the contact region 20 of fig. 1B, showing an image of the boundary where the nano-silver layer 16 covers the copper layer 14', and it can be seen that the copper layer 14' is discolored in the portion of the copper layer 14' covered by the nano-silver layer 16.

Since the copper layer is oxidized and discolored to affect the appearance of the product, there is a need for improvement of the contact structure between the silver nanolayer and the copper layer.

Disclosure of Invention

An object of one embodiment of the present disclosure is to provide a contact structure, in which a protection layer is disposed on a copper layer, so as to prevent oxidation and discoloration of copper in a subsequent photolithography process in a stacked structure of the copper layer and a nano silver layer.

An object of one embodiment of the present disclosure is to provide a passivation layer having a good compatibility with a nano-silver material layer.

Some embodiments of the present disclosure provide a contact structure comprising: the composite coating comprises a substrate, a copper layer, an organic composite protective layer and a nano silver layer. The copper layer is disposed over the substrate. The organic composite type protective layer is arranged on the copper layer and used for preventing the copper layer from being oxidized, wherein the organic composite type protective layer forms a monomolecular adsorption layer on the surface of the copper layer. The nano silver layer is arranged on the organic compound protective layer.

In some embodiments, the organic composite type protective layer includes: a combination of a heterocyclic compound containing a nitrogen atom, or a combination of a coupling agent and a coupling agent.

In some embodiments, the organic complex type protective layer comprises benzotriazole and imidazoline.

In some embodiments, the ratio of benzotriazole to imidazoline is from 1:100 to 100: 1.

In some embodiments, the ratio of benzotriazole to imidazoline is from 1:1 to 1: 3.

In some embodiments, the organic composite protective layer comprises: coupling agents and chelating agents. The coupling agent is a silane coupling agent, a titanate coupling agent, a multifunctional coupling agent, or a combination thereof. The chelating agent is an organic chelating agent, a metal chelating agent, or a combination thereof.

In some embodiments, the ratio of coupling agent to chelating agent is from 1:100 to 100: 1.

In some embodiments, the coupling agent is hexamethyldisiloxane and the chelating agent is ethylenediamine.

In some embodiments, the ratio of hexamethyldisiloxane to ethylenediamine is from 3:1 to 6: 1.

In some embodiments, the coupling agent is isopropyl Titanium Tristearate (TTS) and the chelating agent is ethylenediaminetetraacetic acid (EDTA).

In some embodiments, the organic composite protective layer has a thickness of about 50 to about 100 nanometers.

In some embodiments, Δ a measured after soaking the contact structure in tetramethylammonium hydroxide is no greater than 0.7.

Some embodiments of the present disclosure provide an electronic device comprising a contact structure formed by a copper layer and a nano-silver layer, wherein an organic composite protective layer is disposed between the copper layer and the nano-silver layer.

In some embodiments, at least one side of the copper layer, at least one side of the organic composite type protective layer, and at least one side of the nano-silver layer are aligned with each other in the contact structure of the electronic device.

Other embodiments of the present disclosure provide a method of fabricating a contact structure, comprising: providing a copper layer arranged on a substrate; coating a copper layer with a protective layer solution comprising: an organic protective composition, organic alcohols, and water; forming the protective layer solution into an organic composite protective layer; and arranging a nano silver layer on the organic compound protective layer.

In some embodiments, wherein the organic protective composition comprises: a combination of a heterocyclic compound containing a nitrogen atom, or a combination of a coupling agent and a coupling agent.

In some embodiments, the organic protective composition comprises benzotriazole and imidazoline. Wherein the benzotriazole is present in an amount of about 0.1 to about 10 weight percent of the protective layer solution and the imidazoline is present in an amount of about 0.1 to about 10 weight percent of the protective layer solution.

In some embodiments, the organic protective composition comprises: coupling agents and chelating agents. The coupling agent comprises a silane coupling agent, a titanate coupling agent, a multifunctional coupling agent, or a combination thereof. The proportion of the coupling agent in the protection-layer solution is about 0.05 to about 20 weight percent. The chelating agent comprises an organic chelating agent, a metal chelating agent, or a combination thereof. The chelating agent is present in the protective layer solution in a proportion of about 0.05 to about 20 weight percent.

In some embodiments, further comprising: in a patterning process, the copper layer, the organic composite type protection layer and the nano silver layer are etched.

In some embodiments, at least one side of the copper layer, at least one side of the organic composite type protective layer, and at least one side of the nano-silver layer are aligned with each other after the patterning process.

Drawings

Various aspects of the disclosure will be best understood when the following detailed description is read with reference to the accompanying drawings. It should be noted that the various features may not be drawn to scale in accordance with industry standard practice. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

FIG. 1A is a schematic view of a conventional device including a contact structure before being processed by a photolithography stripping solution;

FIG. 1B is a schematic diagram of a conventional device including a contact structure after being processed by a photolithography stripping solution;

FIG. 1C shows a partial top view of the region 20 of FIG. 1B;

FIG. 2A shows a schematic cross-sectional view of a contact structure according to some embodiments of the present disclosure;

FIG. 2B shows a schematic cross-sectional view of a contact structure, according to some embodiments of the present disclosure;

FIG. 3 shows a schematic cross-sectional view of a device according to some embodiments of the present disclosure;

FIG. 4 shows a top view of a touch panel according to some embodiments of the present disclosure;

FIG. 5A illustrates a schematic top view of a touch panel according to some embodiments of the present disclosure;

FIG. 5B is a schematic cross-sectional view taken along line A-A of FIG. 5A;

FIG. 5C is a schematic cross-sectional view taken along line B-B of FIG. 5B;

fig. 6A-6C show schematic cross-sectional views of different steps of a method of manufacturing a contact structure according to an embodiment of the present disclosure;

FIGS. 7A-7C show top views of comparative example 1 structure of the present disclosure after immersion in a stripping solution;

FIGS. 8A-8C show top views of comparative example 2 structure of the present disclosure after immersion in stripping solution;

FIGS. 9A to 9C show top views of the structure of Experimental example 1 of the present disclosure after immersion in a stripping solution;

fig. 10A to 10C show top views of the structure of experimental example 2 according to the present disclosure after immersion in a stripping solution.

[ notation ] to show

10 component

12: substrate

14 copper layer

14' copper layer

16: nano silver layer

20 contact area

100 contact structure

102 substrate

104 copper layer

106 organic composite protective layer

108 nano silver layer

200 component

210 contact structure

212 substrate

214 copper layer

214' copper layer

216 organic composite type protective layer

218 nano silver layer

300 touch panel

310 display area

312 touch sensing electrode

320 peripheral area

321 signal transmission line

322: lap zone

500 touch panel

510 base plate

520 peripheral lead

536 non-conductive area

550 organic compound type protective layer

602 substrate

604 copper layer

606 organic compound type protective layer

608 nanometer silver layer

Bonding area of BA

C1 first cover

C2 second covering

D1 first direction

D2 second direction

PA peripheral area

TE touch induction electrode

VA display region

Detailed Description

The following disclosure provides different implementations or embodiments to achieve different features of the provided subject matter. Specific embodiments of components and arrangements are described below to simplify the present disclosure. These are, of course, merely embodiments and are not intended to limit the disclosure. For example, in the description that follows, forming a first feature over a second feature may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be disposed between the first and second features, such that the first and second features may not be in direct contact. Further, the present disclosure may repeat reference numerals and/or letters in the various examples. Such repetition is not intended to imply a relationship between the various embodiments and/or configurations discussed.

Furthermore, to facilitate description of the relationship between one element or feature and another element or feature, as illustrated in the figures, spatially relative terms, such as "below," "lower," "above," "upper," "higher," and the like, may be used herein. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may have other orientations (rotated 90 degrees or at other orientations) and the spatially relative terms used herein should be interpreted accordingly.

Referring to fig. 2A, a contact structure 100 is shown, according to some embodiments of the present disclosure. The contact structure includes a substrate 102, a copper layer 104, an organic compound type protection layer 106, and a nano-silver layer 108. The copper layer 104 is disposed on the substrate 102, the organic compound type passivation layer 106 is disposed on the copper layer 104, and the nano-silver layer 108 is disposed on the organic compound type passivation layer 106. In other words, the organic composite passivation layer 106 is disposed between the copper layer 104 and the nano-silver layer 108, which does not affect the electrical connection between the copper layer 104 and the nano-silver layer 108, and the copper oxidation of the copper layer 104 during the stripping solution (e.g., tetramethylammonium hydroxide) treatment in the subsequent photolithography process is suppressed, so the copper layer 104 does not change color.

In other embodiments, as shown in fig. 2B, the nano-silver layer 108 is partially covered over the copper layer 104. In other words, a portion of the copper layer 104 indirectly contacts the nano-silver layer 108 via the organic compound type protective layer 106, and the remaining portion of the copper layer 104 is free of the overlying nano-silver layer.

In some embodiments of the present disclosure, an organic compound type protective layer in a contact structure includes: a combination of a heterocyclic compound containing a nitrogen atom, or a combination of a coupling agent and a coupling agent.

Benzotriazole (BTA) is a copper corrosion inhibitor widely applied, but the application of the Benzotriazole (BTA) is limited, for example, the corrosion inhibition performance of the Benzotriazole (BTA) in an acidic medium is poor, and the matching of the Benzotriazole (BTA) to a nano-silver material needs to be considered.

In some embodiments, the organic compound protection layer 106 comprises a heterocyclic compound containing nitrogen atoms, which can form a monomolecular adsorption layer on the metal surface, such as benzotriazole and imidazoline. Wherein the weight ratio of benzotriazole to imidazoline can be 1:100 to 100:1, for example: 1:100 to 1:1, 1:10 to 1:1, 1:5 to 1:1, or 1:3 to 1:1, and so forth.

In other embodiments, the organic composite protective layer 106 includes a coupling agent and a chelating agent. Wherein the coupling agent is a silane coupling agent, a titanate coupling agent, a multifunctional coupling agent, or a combination thereof; the chelating agent is an organic chelating agent, a metal chelating agent, or a combination thereof. The composition comprising the coupling agent and the chelating agent forms a monomolecular adsorption layer on the metal surface. In some embodiments, the ratio of coupling agent to chelating agent is from 1:100 to 100:1, e.g., from 1:1 to 10:1, from 1:1 to 6:1, from 3:1 to 10:1, or from 3:1 to 6:1, and so forth.

In some embodiments, the organic compound protective layer 106 has a thickness of about 50 to about 100 nanometers, such as 50, 60, 70, 80, 90, or 100 nanometers.

In some embodiments, the contact structure of the present disclosure can be widely applied to the place where the copper layer is in laminated contact with the nano-silver layer. For example: referring to fig. 3, an element 200 according to further embodiments of the present disclosure is shown. The device 200 comprises a contact structure 210. The contact structure 210 includes a substrate 212, a copper layer 214 (wherein the copper layer in indirect contact with the nano-silver layer is denoted as 214), an organic compound type protective layer 216, and a nano-silver layer 218. The contact structure 210 may be a touch panel where a touch electrode meets or overlaps a signal transmission line, the nano-silver layer 218 is the touch electrode, the copper layer 214 is the signal transmission line, and the contact structure 210 enables a signal of the touch electrode to be transmitted to the signal transmission line. Specifically, the contact structure 210 may be located in a peripheral region of the touch panel, or adjacent to a boundary region between the peripheral region and a visible region. The organic composite protective layer 216 is located between the copper layer 214 "and the nano-silver layer 218, and does not affect the electrical connection between the copper layer 214" and the nano-silver layer 218, and the copper layer 214 "is prevented from being oxidized by the stripping solution (e.g. tetramethylammonium hydroxide) during the photolithography process, so that the copper layer 214" is not discolored.

The contact structure provided by the embodiments of the present disclosure may be applied to a display device, for example, an electronic device having a panel, such as a mobile phone, a tablet, a wearable electronic device (e.g., a smart band, a smart watch, a virtual reality device, etc.), a television, a display, a notebook computer, an electronic book, a digital photo frame, a navigator, or the like. The component 10/200 and the touch panel 300 (as shown in fig. 4) according to the embodiment of the present invention can be assembled with other electronic components to form a device/product, such as a display with touch function, for example, the component 10/200 and the touch panel 300 can be attached to a display component (not shown), such as a liquid crystal display component or an Organic Light Emitting Diode (OLED) display component, and optical glue or other similar adhesives can be used for attaching the two components; or an optical film such as a polarizing plate (a stretched polarizing plate or a liquid crystal coated polarizer), an optical retardation film, or the like. The element 10/200, the touch panel 300, and the like according to the embodiment of the invention can be applied to electronic devices such as a portable phone, a tablet computer, a notebook computer, and the like, and can also be applied to flexible products. The element 10/200 and the touch panel 300 according to the embodiment of the present invention can also be manufactured on wearable devices (e.g., watches, glasses, smart clothes, smart shoes, etc.), and automotive devices (e.g., dashboard, car recorder, rearview mirror for vehicle, window, etc.).

Referring to fig. 4, a top view of a touch panel 300 in a display device is shown. The touch panel 300 includes a display area 310 and a peripheral area 320. In the display area 310, the touch sensing electrode 312 is formed of a conductive material containing nano silver. In the peripheral region 320, the signal transmission line 321 is formed of a copper layer. The peripheral region 320 includes a plurality of bonding regions 322, where the touch sensing electrodes are electrically connected to the signal transmission lines for signal transmission. Landing zone 322 may include contact structure 210 as shown in fig. 3.

In some embodiments, in the lap zone 322, the layer of nanosilver wire covers one side surface and part or all of the upper surface of the copper layer of the signal transmission line, with the organic compound type protective layer between the copper layer and the layer of nanosilver wire.

In some embodiments, a copper layer is formed on the peripheral region 320 on the substrate of the touch panel 300, and then an organic composite type protection layer is disposed over the copper layer. Thereafter, a layer of nano-silver lines is formed on the display area 310 and the peripheral area 320 on the substrate, and a layer of nano-silver lines is also formed over the copper layer and the organic composite type protective layer in the peripheral area 320. Then, a photolithography process is performed, including photoresist coating, exposure, development, and etching. Therefore, a touch sensing electrode pattern is formed in the display area 310, and a plurality of spaced signal transmission lines 321 are formed in the peripheral area 320. In the lap joint region treated by etching, the layer of nano-silver wire is positioned above the copper layer and the organic compound type protective layer is positioned between the copper layer and the layer of nano-silver wire. In some embodiments, the silver nanowire layer, the organic composite protective layer, and the copper layer have sides (i.e., common etched surfaces) that are aligned with each other in the peripheral region 320. Then, the spaces between the electrode patterns and between the signal transmission lines are filled with an insulating material.

In an alternative embodiment, the silver nanowire layer is not formed only in the bonding region, but extends to the entire peripheral region 320 to be etched with the copper layer at one time (one time etch). Accordingly, the signal transmission line in the peripheral region 320 is a composite structure of a nano silver line layer/an organic compound type protection layer/a copper layer. Reference is made to fig. 5A-5C in conjunction with the following disclosure.

Fig. 5A is a top view of a touch panel 500 according to some embodiments of the disclosure, and fig. 5B and 5C are cross-sectional views of the line a-a and the line B-B of fig. 5A, respectively. The touch panel 500 includes a substrate 510, a peripheral lead 520, a mark 540, a first cover C1, a second cover C2, an organic compound protection layer 550 (see fig. 5B and 5C), and a touch sensing electrode TE. The number of the peripheral wires 520, the marks 540, the first cover C1, the second cover C2, and the touch sensing electrodes TE may be one or more, and the numbers drawn in the following embodiments and the drawings are only for illustrative purposes and do not limit the present invention.

Referring to fig. 5A, the substrate 510 has a display area VA and a peripheral area PA. The peripheral area PA is disposed at a side of the display area VA, for example, the peripheral area PA may be a frame-shaped area disposed at the periphery of the display area VA (i.e. covering the right side, the left side, the upper side and the lower side), but in other embodiments, the peripheral area PA may be an L-shaped area disposed at the left side and the lower side of the display area VA. As shown in fig. 5A, the present embodiment has eight sets of peripheral wires 520 and the first covers C1 corresponding to the peripheral wires 520 are disposed on the peripheral area PA of the substrate 510; the touch sensing electrode TE is disposed in the display area VA of the substrate 510. The embodiment further includes two sets of marks 540 and a second cover C2 corresponding to the marks 540, which are disposed in the peripheral area PA of the substrate 510. An organic compound protection layer 550 is disposed between the first cover C1 and the peripheral wires 520 to prevent the peripheral wires 520 and the first cover C1 from generating redox reaction in a specific environment (e.g., in the stripping solution). An organic composite protective layer 550 is also provided between the second coverlet C2 and the marker 540; in addition, the first cover C1 and the second cover C2 are respectively disposed on the peripheral lead 520 and the mark 540, so that the upper and lower layers of materials are formed at predetermined positions without being aligned, thereby reducing or avoiding the need to provide an alignment error region in the manufacturing process, reducing the width of the peripheral region PA, and further achieving the narrow frame requirement of the display.

The touch sensing electrode TE of the present embodiment is disposed in the display area VA, and the touch sensing electrode TE can be electrically connected to the peripheral lead 520. Specifically, the touch sensing electrode TE may also be a metal nanowire (metal nanowire) layer at least including a metal nanowire, that is, the metal nanowire forms the touch sensing electrode TE in the display area VA, and the first cover C1 is formed in the peripheral area PA, and the thickness/property of the monolayer formed by the organic compound type protection layer 550 does not affect the electrical conduction between the metal layer and the metal nanowire layer, so that the touch sensing electrode TE can be electrically connected to the peripheral lead 520 through the contact of the first cover C1, the organic compound type protection layer 550 and the peripheral lead 520 to transmit signals. The metal nanowires in the peripheral region PA also form a second cover C2 disposed on the mark 540, and the mark 540 can be widely interpreted as a pattern with a non-electrical function, but not limited thereto. In some embodiments of the present disclosure, the peripheral lead 520 and the mark 540 may be made of the same metal layer (i.e., the same metal material); the touch sensing electrode TE, the first cover C1 and the second cover C2 can be fabricated on the same metal nanowire layer.

In the present embodiment, the mark 540 is a bonding area BA disposed in the peripheral area PA, which is a butt alignment mark, i.e., a mark for aligning an external circuit board (not shown) with the touch panel 500 in a step (i.e., a bonding step) of connecting the external circuit board, such as a flexible circuit board (not shown), to the touch panel 500. However, the disclosure is not limited to the placement or function of the mark 540, for example, the mark 540 may be any inspection mark, pattern or label required in the manufacturing process, and is within the scope of the invention. The mark 540 may have any possible shape such as a circle, a quadrangle, a cross, an L shape, a T shape, etc., and the organic composite protective layer 550 has substantially the same shape as the mark 540.

As shown in fig. 5B and 5C, in the peripheral region PA, a non-conductive region 536 is disposed between adjacent peripheral wires 520 to electrically isolate the adjacent peripheral wires 520 and avoid short circuit. In the present embodiment, the non-conductive region 536 is a gap to isolate adjacent peripheral wires 520. In the patterning step, the above-mentioned gap can be formed by etching, so that the sidewall of the peripheral lead 520, the sidewall of the organic compound protection layer 550 and the sidewall of the first cover C1 are a common etching surface and aligned with each other, i.e. the three are formed in the same etching step; similarly, the sidewalls of the mark 540, the organic compound type protection layer 550 and the second cap C2 are a common etching surface and aligned with each other. Furthermore, the peripheral wires 520, the organic compound type passivation layer 550 and the first cover C1 have the same or similar patterns and sizes, such as long and straight patterns, and the same or similar widths.

As shown in fig. 5C, in the display area VA, a non-conductive area 536 is disposed between the adjacent touch sensing electrodes TE to electrically isolate the adjacent touch sensing electrodes TE and thus avoid short circuit. In the present embodiment, the non-conductive region 536 is a gap to isolate the adjacent touch sensing electrodes TE; in one embodiment, the above-mentioned etching method can be used to fabricate the gap between the adjacent touch sensing electrodes TE. In the present embodiment, the touch sensing electrode TE and the first cover C1 can be fabricated by using the same metal nanowire layer (e.g., a silver nanowire layer), so that at the boundary between the display area VA and the peripheral area PA, the metal nanowire layer forms a climbing structure to form the first cover C1.

In one embodiment, the touch sensing electrodes TE are disposed in a double layer, i.e., the touch sensing electrodes TE are disposed on both the upper and lower surfaces of the substrate, so that the peripheral leads 520, the first cover C1, and the organic compound protection layer 550 are formed on both the upper and lower surfaces of the substrate.

Referring to fig. 6A-6C, a flow chart of fabricating a contact structure according to some embodiments of the present disclosure is shown.

In fig. 6A, a copper layer disposed on a substrate is provided.

In some embodiments, substrate 602 may be rigid or flexible. The substrate 602 may be transparent or opaque. Suitable rigid substrates include, for example, polycarbonate, acrylics, and the like. Suitable flexible substrates include (but are not limited to): polyesters (e.g., polyethylene terephthalate (PET), polynaphthalene, and polycarbonate), polyolefins (e.g., linear, branched, and cyclic polyolefins), polyethylenes (e.g., polyvinyl chloride, polyvinyl dichloride, polyvinyl acetal, polystyrene, polyacrylates, and the like), cellulose ester substrates (e.g., cellulose triacetate, cellulose acetate), polysulfones (e.g., polyethersulfone), polyimides, silicones, or other polymeric films.

A copper layer 604 is disposed over the substrate 602. The copper layer 604 may be disposed on the substrate 602 by electroplating, electroless plating, or other deposition.

In fig. 6B, an organic composite type protective layer is provided on the copper layer. In some embodiments, a protective layer solution may be applied on the copper layer 604. In other embodiments, the structure comprising the copper layer 604 may be immersed in a protective layer solution. The protective layer solution comprises an organic protective composition, an organic alcohol, and water. In some embodiments, the organic protective composition is present in the protective layer solution in an amount of 0.2 to 20 weight percent, the organic alcohol is present in an amount of 0.1 to 10 weight percent, and the water is present in an amount of 10 to 90 weight percent.

In some embodiments, the organic protective composition includes benzotriazole and imidazoline, wherein the benzotriazole is present in an amount of about 0.05 to about 20 weight percent and the imidazoline is present in an amount of about 0.05 to about 20 weight percent of the protective layer solution. Wherein the weight ratio of benzotriazole to imidazoline is in the range of 1:100 to 100:1, such as 1:100 to 1:1, 1:10 to 1:1, 1:5 to 1:1, or 1:3 to 1:1, and the like.

In other embodiments, the organic protective propertyThe composition comprises a coupling agent and a chelating agent. Wherein the coupling agent is a silane coupling agent (general formula (R1-O)₂-Si-R2-Y), titanate coupling agent (general formula: R1-O-Ti- (O-X1-R2-Y) n, n ═ 2, 3 …), multifunctional coupling agent (e.g. commercially available product: organic type trimethoxy silane coupling agent, etc.). Wherein R1 is a functional group capable of undergoing hydrolysis reaction and forming Si-OH, including C_lOMe (Me is a methyl group), OEt (Et is an ethyl group), OC₂H₄OCH₃OSiMe, etc., R2 is a hydrogen atom, methyl group, ethyl group, propyl group, butyl group, phenyl group, cyclohexyl group, vinyl group, propenyl group, oxypropyl group, oxyethylaminopropyl group, mercaptopropyl group, anilinomethyl group, etc.; y is a non-hydrolyzable functional group including a chain alkene functional group (mainly a vinyl functional group) and a terminal C_l、NH₂、SH、N₃A hydrocarbon group having a functional group such as epoxy, (meth) acryloyloxy, isocyanate group, etc., that is, a carbon functional group; x1 may be a carboxyl group, an alkoxy group, a sulfonic acid group, a phosphorus group or the like.

Silane coupling agents include, for example, hexamethyldisiloxane, tetrakis (trimethylsiloxy) silane, 3-glycidoxypropyltrimethoxysilane, or combinations thereof.

Titanate coupling agents include, for example, isopropyl tristearate (TTS), chelating titanium phosphate coupling agents, bis (octyl pyrophosphate) glycolate, bis (dioctyl phosphate) ethylene glycol titanate, or combinations thereof.

The chelating agent is an organic chelating agent, a metal chelating agent, or a combination thereof. The chelating agent may be one or more of ethylenediamine tetraacetic acid (EDTA), ethylenediamine, potassium sodium tartrate, etc.

In some embodiments, the coupling agent is present in an amount of about 0.05 to about 20 weight percent and the chelating agent is present in an amount of about 0.05 to about 20 weight percent of the protective layer solution. The ratio of coupling agent to chelating agent is from 1:100 to 100:1, such as from 1:1 to 10:1 or from 1:1 to 6:1 or from 3:1 to 10:1 or from 3:1 to 6:1, and so forth.

In some embodiments, the alcohol is propanol, trimethyl butanol, dipentaerythritol, diacetone alcohol, ethylene glycol, or a mixture thereof.

In fig. 6B, forming the protection layer solution into an organic composite protection layer 606 is further included. In some embodiments, drying is performed, for example, by air gun drying, and a pre-bake treatment is performed.

In fig. 6C, a nano silver layer is disposed on the organic composite type protective layer.

As used herein, "metal nanowires (metal nanowires)" is a collective term referring to a collection of metal wires comprising a plurality of elemental metals, metal alloys or metal compounds (including metal oxides), wherein the number of metal nanowires contained therein does not affect the scope of protection claimed by the present disclosure; and at least one cross-sectional dimension (i.e., cross-sectional diameter) of the single metal nanowire is less than about 500nm, preferably less than about 100nm, and more preferably less than about 50 nm; while the metal nanostructures referred to in this disclosure as "wires" have primarily high aspect ratios, e.g., between about 10 and 100,000, more particularly, the metal nanowires may have aspect ratios (length: diameter of cross section) greater than about 10, preferably greater than about 50, and more preferably greater than about 100; the metal nanowires can be any metal including, but not limited to, silver, gold, copper, nickel, and gold-plated silver. Other terms such as silk (silk), fiber (fiber), tube (tube), etc. having the same dimensions and high aspect ratio are also within the scope of the present application. In some embodiments, the nano-silver layer 608 is prepared by coating a coating composition containing nano-silver structures. To form the coating composition, the silver nanowires are typically dispersed to form a silver nanowire ink/dispersion to aid in the coating process. It is to be understood that any suitable liquid that forms a stable nano-silver wire dispersion may be used, as described herein. Preferably, the silver nanowires are dispersed in water, alcohols, ketones, ethers, hydrocarbons or aromatic solvents (benzene, toluene, xylene, etc.). More preferably, the liquid has a volatility and a boiling point of no greater than 200 ℃, no greater than 150 ℃, or no greater than 100 ℃. After the curing/drying step, the solvent and other substances in the slurry are volatilized, and the metal nanowires are randomly distributed on the surface of the substrate, and the metal nanowires can contact with each other to provide a continuous current path, thereby forming a conductive network (conductive network).

In addition, a film layer may be coated to form a composite structure with the metal nanowires, which has certain chemical, mechanical and optical properties, such as adhesion between the metal nanowires and the substrate, or better physical mechanical strength, so the film layer may be referred to as a matrix (matrix). In yet another aspect, the film layer is made of certain specific polymers to provide additional scratch and abrasion resistant surface protection to the metal nanowires, in which case the film layer may also be referred to as a hard coat or overcoat (over coat), and the use of materials such as polyacrylates, epoxies, polyurethanes, polysilanes, silicones, poly (silicon-acrylic) and the like may provide the metal nanowires with higher surface strength to improve scratch resistance. In addition, ultraviolet light stabilizers (UV stabilizers) can be added into the film layer to improve the ultraviolet resistance of the metal nanowire. However, the above is merely illustrative of other possibilities for additional functions/names of the film layer and is not intended to limit the present application.

Thereafter, the device may perform a patterning process, including pattern exposure, development, etching, etc., to form the copper layer 604, the nano-silver layer 608, or both, into a desired circuit pattern.

In the following, the embodiment of the present disclosure is verified by combining with the comparative example and the experimental example, after a laminated structure including a copper layer and a nano-silver layer is formed, the laminated structure is immersed in a commonly used stripping solution, "tetramethylammonium hydroxide", of a developing process, to observe whether the copper layer located below the nano-silver layer is discolored. The color change phenomenon can be observed through a Lab reflection color mode, the specific experimental example results are shown in the following table 1, and actual images of a plurality of groups of experimental examples are selected for description.

Watch 1

Comparative example 1.

A copper layer is taken, the copper layer is divided into a first area and a second area, and the nano silver layer is arranged on the first area of the copper layer and directly contacts the copper layer.

Fig. 7A to 7C show images of comparative example 1 after soaking in the tetramethylammonium hydroxide solution for 5 minutes, 10 minutes, and 15 minutes, respectively. It was shown that in comparative example 1, the portion of the nanosilver-covered copper layer (first region, at the left side in the figure) was significantly discolored after 5 minutes immersion in the tetramethylammonium hydroxide solution, and was color-different from the second region (at the right side in the figure). After soaking in the tetramethylammonium hydroxide solution for 10 minutes, the phenomenon of discoloration at the first area of the copper layer is more obvious. After soaking in tetramethylammonium hydroxide solution for 15 minutes, the first zone of the copper layer even turned brown. Referring to table 1, the optical analysis of the copper layer after soaking was performed, and the color change of the copper layer was analyzed with index a by quantitative analysis in Lab reflection color mode under the condition of comparative example 1 without adding a protective layer. As shown in table 1, the amount of change a was 0.7 under the conditions of comparative example 1, and thus Δ a was not more than 0.7 as an index for quantifying no discoloration/discoloration of copper.

Comparative example 2.

Taking a copper layer, wherein the copper layer is divided into a first area and a second area, soaking the copper layer in a protective layer solution, and the organic protective composition in the protective layer solution comprises benzotriazole and imidazoline in a weight ratio of 2: 1. And taking out the copper layer, drying by using an air gun, and pre-baking. Next, a nano-silver layer is coated at a first region on the protective layer on the treated copper layer.

Fig. 8A to 8C show images of comparative example 2 after soaking in tetramethylammonium hydroxide solution for 5 minutes, 10 minutes, and 15 minutes, respectively. It was shown that in comparative example 2, the portion of the nano-silver copper-clad layer (first region, at the left side in the figure) was slightly discolored after soaking in tetramethylammonium hydroxide solution for 5 minutes, with some color difference from the second region. After soaking in tetramethylammonium hydroxide solution for 10 minutes, the discoloration of the first area of the copper layer became evident, and the difference from the second area was more evident. After soaking in the tetramethylammonium hydroxide solution for 15 minutes, the first zone of the copper layer discolors more obviously. Since comparative example 2 had copper discoloration observed by naked eyes, a-x measurement was not performed.

Experimental example 2.

Taking a copper layer, dividing the copper layer into a first area and a second area, and soaking the copper layer in a protective layer solution, wherein the organic protective composition in the protective layer solution comprises benzotriazole and imidazoline in a weight ratio of 1: 2. And taking out the copper layer, drying by using an air gun, and pre-baking. Next, a nano-silver layer is coated at a first region on the protective layer on the treated copper layer.

Fig. 9A to 9C show images of experimental example 2 after soaking in tetramethylammonium hydroxide solution for 5 minutes, 10 minutes, and 15 minutes, respectively. It was shown that in experimental example 2, the portion of the nano-silver copper-clad layer (first region, at the left side in the figure) was not significantly discolored after soaking in the tetramethylammonium hydroxide solution for 5 minutes, 10 minutes, and 15 minutes, and was not significantly discolored from the second region of the copper layer. When the protective layer formed by the composite formula of benzotriazole and imidazoline is analyzed by experimental example 1, experimental example 2, experimental example 3 (see table 1) and comparative example 2, a better anti-heterochrosis effect can be obtained under the condition that the component proportion (such as weight percentage) of benzotriazole is less than or equal to that of imidazoline. However, as the proportion of the imidazoline component increases, the copper begins to appear different, and Δ a in table 1 also approaches 0.7 as the proportion of the imidazoline component increases. Therefore, the application considers that the weight ratio of benzotriazole to imidazoline is in the range of 1: 1-1: 3, and the effect is better.

Experimental example 5.

Taking a copper layer, wherein the copper layer is divided into a first area and a second area, and soaking the copper layer in a protective layer solution, wherein the organic protective composition in the protective layer solution comprises hexamethyldisiloxane and ethylenediamine in a weight ratio of 5: 1. And taking out the copper layer, drying by using an air gun, and pre-baking. Next, a nano-silver layer is coated at a first region on the protective layer on the treated copper layer.

Fig. 10A to 10C show images of experimental example 5 after soaking in tetramethylammonium hydroxide solution for 5 minutes, 10 minutes, and 15 minutes, respectively. It was shown that in experimental example 5, the portion (first region) of the copper-clad layer on nanosilver did not undergo significant discoloration and did not undergo significant color difference from the second region of the copper layer after immersion in the tetramethylammonium hydroxide solution for 5 minutes, 10 minutes, and 15 minutes. As shown in table 1, the amount of change a was 0.14 under the conditions of experimental example 5. As analyzed in Experimental examples 4 and 5 (see Table 1), the protective layer formed by the composite formulation of hexamethyldisiloxane and ethylenediamine can obtain better anti-discoloration effect under the condition that the component ratio (such as weight percentage) of hexamethyldisiloxane is greater than that of ethylenediamine. However, as the ratio of hexamethyldisiloxane to ethylenediamine was adjusted to 7:1, the copper started to develop a different color, as measured by Δ a exceeding 0.7 in comparative example 3 of table 1. Therefore, the weight ratio of the hexamethyldisiloxane to the ethylenediamine is 3:1 to 6: 1.

As can be seen from fig. 9A to 9C and fig. 10A to 10C, in the stacked structure of the copper layer and the nano-silver layer, the organic composite protective layer can provide a significant oxidation prevention effect during the film-removing solution treatment, so that the copper layer covering the nano-silver layer is not oxidized and discolored.

Experimental example 6 of Table 1 is an embodiment of another combination of coupling agent and chelating agent. In Experimental example 6, the coupling agent was isopropyl tristearate (TTS) and the chelating agent was ethylenediaminetetraacetic acid (EDTA) in a weight ratio of 8: 1.Δ a measured after soaking tetramethylammonium hydroxide was 0.35. Therefore, the passivation layer of example 6 also provides a significant oxidation prevention effect, so that the copper layer overlying the nano-silver layer is not oxidized and discolored.

Embodiments of the present disclosure may solve the copper discoloration problem that may occur after a photolithography process on a contact structure, so that a device including the contact structure may be produced by the photolithography process. The electronic device comprising the conductive film layer is manufactured by a yellow light manufacturing method, so that better time efficiency can be provided, and the production cost can be reduced.

While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

1. A contact structure, comprising:

a substrate;

a copper layer disposed on the substrate;

an organic compound type protection layer arranged on the copper layer and used for preventing the copper layer from being oxidized, wherein the organic compound type protection layer forms a monomolecular adsorption layer on the surface of the copper layer; and

a nano silver layer arranged on the organic compound type protective layer.

2. The contact structure of claim 1, wherein said organic compound type protection layer comprises: a combination of a heterocyclic compound containing a nitrogen atom, or a combination of a coupling agent and a coupling agent.

3. The contact structure of claim 1, wherein the organic complexing protective layer comprises benzotriazole and imidazoline.

4. The contact structure of claim 3, wherein the ratio of benzotriazole to imidazoline is 1:100 to 100: 1.

5. The contact structure of claim 3, wherein the ratio of benzotriazole to imidazoline is 1:1 to 1: 3.

6. The contact structure of claim 1, wherein said organic compound type protection layer comprises:

a coupling agent which is a silane coupling agent, a titanate coupling agent, a multifunctional coupling agent, or a combination thereof; and

a chelating agent which is an organic chelating agent, a metal chelating agent, or a combination thereof.

7. The contact structure of claim 6, wherein the ratio of the coupling agent to the chelating agent is from 1:100 to 100: 1.

8. The contact structure of claim 6 wherein the coupling agent is hexamethyldisiloxane and the chelating agent is ethylenediamine.

9. The contact structure of claim 8, wherein the ratio of hexamethyldisiloxane to ethylenediamine is 3:1 to 6: 1.

10. The contact structure of claim 6, wherein the coupling agent is isopropyl tri-stearate (TTS) and the chelating agent is ethylenediaminetetraacetic acid (EDTA).

11. The contact structure of claim 1, wherein the organic compound type protection layer has a thickness of 50 to 100 nm.

12. The contact structure of claim 1, wherein Δ a measured after soaking said contact structure in tetramethylammonium hydroxide is not greater than 0.7.

13. An electronic device comprising a contact structure according to any of claims 1 to 11.

14. A method of fabricating a contact structure, comprising:

providing a copper layer arranged on a substrate;

coating a protective layer solution on the copper layer, the protective layer solution comprising:

an organic protective composition in an amount of 0.1 to 10 weight percent of the protective layer solution;

organic alcohol with the content of 0.1 to 10 weight percent of the protective layer solution; and

water in an amount of 10 to 90 weight percent of the protective layer solution;

forming the protective layer solution into an organic compound protective layer; and

and a nano silver layer is arranged on the organic compound protective layer.

15. The method of claim 14, wherein the organic protective composition comprises: a combination of a heterocyclic compound containing a nitrogen atom, or a combination of a coupling agent and a coupling agent.

16. The method of claim 15, wherein the organic protective composition comprises:

benzotriazole, the content of which is 0.1 to 10 weight percent of the protective layer solution; and

imidazoline in an amount of 0.1 to 10 weight percent of the protective layer solution.

17. The method of claim 16, wherein the organic protective composition comprises:

a coupling agent comprising: a silane coupling agent, a titanate coupling agent, a multifunctional coupling agent, or a combination thereof, wherein the proportion of the coupling agent in the protection-level solution is 0.05 to 20 weight percent; and

a chelating agent comprising: an organic chelating agent, a metal chelating agent, or a combination thereof, in a proportion of 0.05 to 20 weight percent of the protective layer solution.

18. The method of fabricating a contact structure of claim 14, further comprising: in a patterning process, the copper layer, the organic composite type protection layer and the nano silver layer are etched.

19. The method of claim 18, wherein a side of the copper layer, a side of the organic composite passivation layer, and a side of the nano-silver layer are aligned with each other after the patterning process.