Improved adhesion strength of metal-organic interfaces in electronic devices

Abstract

A method of improving adhesion of a metal-organic interface in an electronic device includes providing a substrate having a metal structure, treating a surface of the metal structure to form a single-layer coating of a selected chemical composition on the surface, and coating the treated surface with an organic material.

Description

[0001] Cross-references to related applications

[0002] This application is a continuation-in-part of U.S. Patent Application No. 18 / 137,876, filed April 21, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to improving the adhesion strength of metal-organic interfaces in electronic devices. Background Technology

[0004] The fabrication process of electronic (or photonic) devices consists of a series of sequential steps to create circuitry on wafers or panels (collectively referred to herein as substrates) of materials such as semiconductor wafers, glass panels, printed circuit boards, organic / ceramic substrates, etc. Defects introduced during the fabrication process from any source reduce the yield of the resulting devices. One cause of defects is insufficient adhesion at the metal-organic interface of the device. Electronic devices (e.g., package substrates, integrated circuit chips, optoelectronic devices, etc.) include many metal-organic interfaces. The adhesion between metal components (e.g., interconnects, landing pads, vias, etc.) and organic components (e.g., dielectric materials, molding compounds, underfill materials, etc.) at the metal-organic interface can be compromised for a variety of reasons. These include, for example, the quality / structure of the materials at the interface, embedded particles / residues (fragments, chemicals, etc.) at the interface, high thermomechanical interfacial forces (e.g., due to CTE mismatch), etc. Poor adhesion between a metal (e.g., a copper pad) and an organic material (e.g., a dielectric) at the interface can introduce defects (e.g., delamination, cracks, etc.) at the interface and lead to reduced device yield and / or reliability. A strong metal-organic interface ensures that downstream processes (e.g., chemicals and / or process conditions used during downstream processes) do not degrade the adhesion strength of the interface. Furthermore, the miniaturization of electronic devices requires the miniaturization of integrated circuit (IC) substrates (e.g., printed circuit boards (PCBs)) consisting of organic material layers (often referred to as stacked layers or dielectric layers, including, for example, polymers, stacked layers, etc.) and metal layers (e.g., copper, aluminum, gold, etc.) (e.g., coatings, lines, planes, vias, etc.). To fabricate fine copper circuits with small line widths and space widths for next-generation electronic devices, improved adhesion between copper and organic layers is necessary.

[0005] Current methods for improving adhesion rely on surface roughening of the metal surface to allow overlapping dielectric layers to mechanically interlock with the metal surface and improve adhesion. For example, the surfaces of metal interconnects are modified by methods such as etching or plasma ablation before depositing the dielectric layer to improve adhesion between the metal and the dielectric. However, such surface roughening can adversely affect the electrical performance of electronic devices and / or lead to reliability issues. For example, high-frequency applications may require low surface roughness, and etching / ablation may require additional cleaning steps and / or cause debris from the roughening process to be redeposited and embedded in the interface. The systems and methods for improving adhesion disclosed herein can mitigate at least some of the aforementioned drawbacks. However, the scope of this disclosure is defined by the claims, and not by the ability to solve any problem. Summary of the Invention

[0006] Electronic devices with improved interfacial adhesion strength at metal-organic interfaces and methods for improving interfacial adhesion strength are disclosed.

[0007] In one embodiment, a method for improving the adhesion of a metal-organic interface in an electronic device is disclosed. The method includes: providing a substrate having a metal structure formed thereon; treating the surface of the metal structure with a vapor of a chemical composition to form a monolayer coating of the chemical composition on the surface of the metal structure, wherein the chemical composition includes at least one of: (i.) phosphoric acid 2-hydroxyethyl methacrylate ester, (ii.) vinylphosphonic acid, (iii.) N-[3-(dimethylamino)propyl]methacrylamide, (iv.) 2-(diethylamino)ethyl methacrylate, (v.) 2-(dimethylamino)ethyl methacrylate, (vi.) 2-aminoethyl methacrylate hydrochloride, or (vii.) 2,3-glycidyl methacrylate; and, after treating the surface of the metal structure, coating the treated surface with an organic material, wherein the metal-organic interface between the treated surface of the metal structure and the coated organic layer has improved adhesion.

[0008] In another embodiment, a method for improving the adhesion of a metal-organic interface in an electronic device is disclosed. The method includes: providing a substrate having a copper interconnect structure; and treating the surface of the copper interconnect structure with a vapor of a chemical composition to form a monolayer coating of the chemical composition on the surface of the copper interconnect structure, wherein the chemical composition includes at least one of the following: (i.) 2-hydroxyethyl methacrylate, (ii.) vinylphosphonic acid, (iii.) N-[3-(dimethylamino)propyl]methacrylamide, (iv.) 2-(diethylamino)ethyl methacrylate, (v.) 2-(dimethylamino)ethyl methacrylate, (vi.) 2-aminoethyl methacrylate hydrochloride, or (vii.) 2,3-glycidyl methacrylate. The method may further include: coating the treated surface with parylene after treating the surface of the copper interconnect structure. The metal-organic interface between the treated surface of the copper interconnect structure and the coated parylene has improved adhesion.

[0009] In yet another embodiment, an electronic device having a metal-organic interface is disclosed. The device may include: a substrate having a metallic structure, and a monolayer coating of a chemical composition formed on the surface of the metallic structure. The chemical composition may include at least one of the following: (i.) 2-hydroxyethyl methacrylate, (ii.) vinylphosphonic acid, (iii.) N-[3-(dimethylamino)propyl]methacrylamide, (iv.) 2-(diethylamino)ethyl methacrylate, (v.) 2-(dimethylamino)ethyl methacrylate, (vi.) 2-aminoethyl methacrylate hydrochloride, or (vii.) 2,3-glycidyl methacrylate. The device may also include an organic material layer disposed on the monolayer coating of the chemical composition. Attached Figure Description

[0010] The accompanying drawings, which are incorporated herein and constitute a part of this disclosure, illustrate exemplary embodiments and, together with the specification, serve to explain the disclosed principles. In these drawings, where appropriate, reference numerals illustrating the same or similar structures, components (parts), materials, and / or elements in different drawings are similarly labeled. It should be understood that, in addition to those specifically shown, various combinations of structures, components (parts), and / or elements are contemplated and are within the scope of this disclosure.

[0011] For the sake of brevity and clarity, the accompanying drawings depict the general structure of the various described embodiments. Details of well-known components or features may be omitted to avoid obscuring other features, as these omitted features are well-known to those skilled in the art. Furthermore, features in the drawings are not necessarily drawn to scale. The dimensions of some features may be enlarged relative to other features (e.g., see Figure 3B) to improve understanding of the exemplary embodiments. Those skilled in the art will understand that features in the drawings are not necessarily drawn to scale and should not be construed as representing dimensional or proportional relationships between different features in the figures unless otherwise stated. Additionally, even if not explicitly stated, aspects described with reference to one embodiment or drawing may apply to other embodiments or drawings and may be used in conjunction with other embodiments or drawings.

[0012] Figure 1A This is a simplified schematic diagram of a metal-organic interface in electronic devices;

[0013] Figure 1B It includes Figure 1A A schematic cross-sectional view of an exemplary electronic device with an interface;

[0014] Figure 2A It is to handle Figure 1A A flowchart of an exemplary method for a metal surface in a metal-oxide interface; and

[0015] Figure 2B It is to handle Figure 1A A flowchart of another exemplary method for a metal surface in a metal-oxide interface. Detailed Implementation

[0016] All relative terms, such as “about,” “substantially,” “approximately,” etc., indicate a possible variation of ±10% (unless otherwise stated or specified as another degree of variation). For example, a feature disclosed as approximately “t” units thick (or length, width, depth, etc.) may vary in thickness from (t-0.1t) to (t+0.1t) units. In some cases, this specification also provides context for some of the relative terms used. For example, a structure described as substantially flat (e.g., an edge of a coating) may deviate from perfectly flat by ±10%. Furthermore, ranges described as varying from 5 to 10 (5-10) or between 5 and 10 (5-10) include endpoints (i.e., 5 and 10). Additionally, as used herein, a component including at least one of A, B, or C is used to refer to a component including one or more of A, B, or C. For example, a component including only A, a component including only B, a component including only C, a component including both A and B, a component including both A and C, a component including A, B, and C, etc.

[0017] Unless otherwise defined, all technical terms, symbols, and other scientific terms or specialized terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Some components (assemblies), structures, and / or processes described or referenced herein are well understood by those skilled in the art and are typically employed using conventional methods. These components (assemblies), structures, and processes will not be described in detail. All patents, applications, published applications, and other publications mentioned herein and incorporated herein by reference are incorporated in their entirety. If any definition or description set forth in this disclosure is contrary to or inconsistent with the definitions and / or descriptions in these references, the definitions and / or descriptions set forth in this disclosure shall take precedence over those definitions and / or descriptions in the references incorporated by reference. None of the references described or cited herein are considered prior art relative to the present disclosure. It should be noted that in this disclosure, the term "electronic device" is used to encompass all components and electronic / photonic assemblies (e.g., packaging substrates, printed circuit boards, interposers, integrated circuit chips, etc.).

[0018] The following discussion describes exemplary methods for improving the interfacial adhesion strength of metal-organic interfaces in electronic devices, and the resulting electronic devices having improved interfacial adhesion strength. Figure 1A yes Figure 1B A simplified representation of the metal-organic interface 30 of the exemplary electronic device shown. Interface 30 includes a metal structure 10 (e.g., coating, line, plane, pad, via wall, etc.), wherein an organic layer 20 is formed on one of its surfaces. In the electronic device of this disclosure, a chemically composed monolayer coating 15 formed at the interface between the metal structure 10 and the organic layer 20 improves the adhesion strength of the metal-organic interface. The organic layer 20 can be formed on the metal structure 10 by any known method used in the manufacture of the electronic device (e.g., deposition, plating, growth, spraying, etc.). In the exemplary embodiment, Figure 1A The metal-organic interface 30 can be represented as Figure 1BThe interface of an exemplary packaging substrate 40 for an electronic device. The packaging substrate 40 is an 8-layer high-density interconnect (HDI) substrate, wherein two stacked layers 34 (referred to as a 2+4+2 (2 stacked layers + 4 core layers + 2 stacked layers) stack) are present on each side of a core stack 32 having 4 circuit layers. The core stack 32 may be made of BT (bismaleimide triazine) epoxy resin with embedded glass fibers that separate the copper interconnects of the core from the plated through-hole (PTH) vias. The stacked layers 34 located on either side of the core stack 32 may also include an organic dielectric material (such as parylene) that separates the copper interconnect structures (e.g., interconnects, interlayer vias, bond pads, etc.) in these layers. In some embodiments, a BT epoxy core stack 32 can be fabricated first, and then stacked layers 34 can be sequentially formed on the top and bottom (e.g., by deposition, photolithographic patterning, etching, etc.). Figure 1A and 1B As shown by the dashed circle in the image, Figure 1A The metal-organic interface 30 can be located anywhere on the packaging substrate 40. Although interface 30 is described as part of the packaging substrate 40, as previously stated, interface 30 can be part of any electronic device, such as the back-end structure of an IC die.

[0019] exist Figure 1A and 1B In the illustrated embodiment, the material of the metal structure 10 is a conductive interconnect material (e.g., copper). The material of the organic layer 20 depends on the location of the interface 30 within the packaging substrate 40. For example, if the interface 30 is an interface in the core stack 32, the organic layer 20 can be an organic material used in the core (e.g., BT epoxy resin, etc.). And if the interface 30 is an interface in the stacked layer 34, the organic layer 20 can be an organic material used in the stacked layer (e.g., parylene, ABF, or any other suitable organic material). For brevity, this document will describe improving the adhesion strength of the copper-parylene interface. In other words, in the following discussion, the metal structure 10 is made of copper (or includes copper), and the organic layer 20 is made of parylene (or includes parylene). Parylene is a chemical compound with the formula (C8H8). nThe term "n" refers to a series of polymers, where n represents the number of repeating monomer units. It should be noted that these materials (e.g., copper and parylene) are merely exemplary. Typically, the organic layer 20 can comprise any material, such as polymers, dielectrics, epoxy resins (e.g., underfill epoxy, overmolded epoxy, etc.), or composites consisting of two or more of the aforementioned materials. For example, a composite of glass fiber, epoxy resin, and silica-filled material, with a copper layer on top, is commonly referred to as a copper-clad laminate. Furthermore, the metal structure 10 can comprise any metal or alloy, such as, for example, copper, gold, titanium, aluminum, etc. Additionally, the metal structure 10 of the interface 30 can be any part of the interconnect structure on the packaging substrate 40 (e.g., interconnects, power planes, ground planes, interlayer vias, PTHs, bonding pads, etc.).

[0020] refer to Figure 1A In the method of this disclosure, after the metal structure 10 is formed by any suitable method, and before an organic layer 20 is formed on the surface of the metal structure 10 (e.g., by depositing an organic material layer), the surface of the metal layer is treated with a chemical composition. The chemical composition reacts with the metal and forms a monolayer coating 15 of the chemical composition (e.g., a thin layer of the reactive compound) on the surface of the metal structure 10. This monolayer coating 15 of the chemical composition improves the adhesion of the organic layer 20, which is then formed (e.g., deposited) on top of the monolayer coating 15 onto the metal structure 10. It should be noted that when the metal surface is treated with a chemical composition, in some cases, the chemical composition itself may not deposit on the surface to form a monolayer coating. Instead, the chemical composition may react with the metal surface to form a monolayer coating, wherein a functional part of the chemical composition forms or is contained within the monolayer coating. Furthermore, as those skilled in the art will recognize, the coating material can react with the substrate material (e.g., the substrate metal) and change its composition over time. It should be noted that, as used herein, the term "chemically composed monolayer coating" refers to all of the above-mentioned cases. In other words, the term "chemically composed monolayer coating" broadly refers to a monolayer coating having the following characteristics: (a) a component essentially made of a chemical component (used to treat a substrate), (b) a component comprising a functional portion of the chemical component, and (c) a component as a product of a chemical reaction between the chemical component and the substrate material. In some embodiments, the composition of the monolayer coating 15 may be determined using energy dispersive spectroscopy (EDS) or other known techniques. A "monolayer coating" refers to a single layer of molecules or atoms deposited on a surface to form a uniform and thin coating. This type of coating is extremely thin, typically nanoscale, and consists of a self-assembled layer of closely packed molecules or atoms. When a metal surface is treated with a chemical component, the molecules or atoms can organize themselves into a uniform layer due to intermolecular forces.

[0021] The metal structure 10 can be formed by any process (e.g., IC manufacturing process) used to form a metal structure on an underlying substrate. For example, on an underlying substrate (e.g., Figure 1B An exemplary process for forming the metal structure 10 on the core stack 32) may include depositing a metal (e.g., copper) layer on a substrate (e.g., by chemical vapor deposition (CVD), etc.) and patterning the metal layer into a desired circuit pattern using conventional photolithography processes. The organic layer 20 may also be formed on top of the metal structure 10 by any known process used in the fabrication of the packaging substrate 40 (e.g., deposition, plating, spraying, etc.). Prior to forming the organic layer 20, a monolayer coating 15 of chemical composition is formed or deposited on the surface of the metal structure, for example by vapor deposition. Typically, the monolayer coating 15 may be about 1-30 angstroms thick. In some embodiments, the monolayer coating 15 may be between about 1-10 angstroms thick. It should be noted that the “thickness” of a monolayer can be the length of a molecule of the chemical composition. It should be noted that the monolayer coating 15 may not completely cover the treated metal surface. Instead, there may be areas on the metal surface without the monolayer coating (or with minimal coating). In other words, the coverage of the monolayer coating on the substrate may not be 100%. If a measurement technique such as ellipsometry is used to measure the “thickness” of a monolayer coating, the resulting thickness can be between 0 and 100% of the length of a molecule, depending on the percentage of coverage of the monolayer coating on the substrate.

[0022] Vapor deposition is a controlled process that provides a stable environment for forming a uniform, self-assembled monolayer coating 15 of chemical composition on the surface of a metal structure 10. The monolayer coating 15 can provide reactivity and functionality to the surface of the metal structure 10 by generating durable and covalent bonds between the functionalized part of the chemical composition and the underlying metal structure 10. As is known to those skilled in the art, the physical and chemical properties of a solid surface are largely determined by the outermost layer of chemical groups or atoms. Therefore, coating the surface of the metal structure 10 with a monolayer coating 15 of chemical composition allows the metal structure 10 to form strong bonds with the molecules of the organic layer 20 to be deposited (or otherwise formed) thereon. Although surface modification of metal surfaces is known (see, for example, Sagiv; J. Am. Chem. Soc.; January 1, 1980; 102; pp. 92-98), successful coupling agents for metals that form hydrolyzed or mechanically unstable surface oxides have not previously been disclosed. Previously, suitable chemical compositions for bonding between metal surfaces and organic layers have not been disclosed.

[0023] The chemical composition used in this disclosure for treating metal surfaces is a suitable coupling agent to improve the adhesion of organic materials to mechanically unstable metal surfaces (e.g., electroless copper, physical vapor deposition (PVD) copper, electroplated copper, electroplated gold, PVD gold, etc.) at metal-organic interfaces. The disclosed chemistry is based on the chemical properties of the substrate. The chemical composition allows for the coating (coating) of various metal substrates on both smooth and rough surfaces, providing excellent post-deposition film stability. The functionalized and reactive groups of the selected chemical composition allow for various bonding mechanisms between the metal and the organic material. The disclosed chemical composition improves the bonding strength between parylene and the copper structure on the substrate. These bonds are expected to anchor between the functionalized groups of the chemical composition and the metal surface, and to generate in-plane crosslinks, which improves the stability of the monolayer.

[0024] Table 1 lists the metal-organic interfaces that can be used ( Figure 1A Some chemical components of the effective coupling agent for the interface 30). These components are particularly suitable for improving the adhesion of organic materials (e.g., parylene) to the surface of copper metal structures 10 formed by various processes (e.g., electroless copper plating, physical vapor deposition (PVD) copper, electroplated copper, etc.). It should be noted that the list in Table 1 is not an exhaustive list, and suitable chemical components of this disclosure may include other similar components. Typically, the selected chemical components have a boiling point below about 250°C at a pressure between about 0.1 and 10 Torr.

[0025] Table 1: Exemplary chemical compositions for improving adhesion at metal-organic interfaces

[0026]

[0027] It has been determined that using vapors of at least one of the aforementioned chemical components to treat the surface of the metal structure 10 via vapor deposition produces a monolayer coating 15 of the chemical composition on the treated metal surface. This monolayer coating 15 improves the adhesion strength of the interface 30 when organic material 20 is deposited on the treated surface. In the vapor phase, the process is carried out using individual molecules, forming an ultrathin monolayer coating 15 of the chemical composition on the metal structure 10. The aforementioned chemical components have been selected such that they do not react head-to-tail and therefore do not aggregate to form thick layers. For some chemistry, in the liquid phase, chemicals may have a tendency to cluster together and form inhomogeneous layers. As the size of device features decreases, vapor deposition has the additional benefit of being able to diffuse through small openings.

[0028] The specific chemical composition chosen for any application depends on the materials, process conditions, etc., that form the interface. For example, the materials, process conditions, etc., constituting the metal structure 10 and the organic layer 20. It has been determined that the disclosed chemical compositions effectively improve adhesion to both smooth and rough surfaces and provide good film stability after deposition. Although the disclosed chemical compositions are intended to be applicable to a variety of materials used as the metal structure 10 and organic layer 20 in electronic devices, they have been found to be particularly effective in improving adhesion between the organic layer 20 containing parylene and the copper-containing metal structure 10. These chemical compositions are also expected to effectively improve the adhesion strength between any metal with unstable oxides and polyamides. It is believed that the functionalized and reactive groups of the disclosed chemical compositions will allow for a variety of bonding mechanisms between the metal structure 10 and the organic layer 20. The bonds formed are expected to anchor between the functionalized groups of the chemical compositions and the metal surface, and to promote in-plane cross-linking, which improves monolayer stability.

[0029] In some embodiments, a vapor deposition process can be used to treat the surface of the metal structure 10 with one or more of the aforementioned chemical components. In some embodiments of the exemplary vapor deposition process, vapors of the desired chemical components are introduced into a processing chamber in which a substrate with the exposed metal structure 10 is held (e.g., Figure 1B (Packaging substrate 40). The processing chamber of any suitable semiconductor processing apparatus can be used for vapor-phase silane deposition processes. For example, the processing chamber of a processing apparatus described in any of U.S. Patent Nos. 7,727,588, 8,252,375, 8,361,548, 10,147,617, 10,319,612, 10,490,431, 11,367,640, 11,444,053, 11,335,662, 11,296,049, 11,456,274, and 11,465,225. Each of these references is incorporated herein by reference in its entirety. In some embodiments, the temperature and pressure of the vapor in the processing chamber can be regulated to retain the applied chemical component in its vapor phase. The exact values ​​(or ranges) of temperature and pressure used to retain the chemical component in its vapor phase depend on the applied component and application (e.g., the materials involved, etc.). Typically, the metal structure 10 can be exposed to vapors for any desired time (e.g., about 3 minutes to 2 hours). In some embodiments, the metal structure 10 can be exposed to the vapors of the chemical component for a period of time or duration of about 10-30 minutes or about 15-20 minutes. In some embodiments, longer durations can be used. A monolayer coating 15 of the chemical component can be formed during the initial phase of exposure (e.g., the first 10-20 minutes). Increasing the exposure time can increase the density of the formed monolayer coating 15.

[0030] Figure 2AThis is a flowchart of an exemplary process 100A that can be used to process a substrate on which a metal structure 10 is formed. One or more substrates having the metal structure 10 can be placed in a processing chamber. The surfaces of the substrate and / or the metal structure 10 can be prepared for vapor treatment (step 110). In some embodiments, surface preparation may include wet processes, such as a dilute acid bath or exposing the surface to a dry, active plasma to remove contaminants and native oxides from the surface. The processing chamber can then be vented to remove oxygen and moisture (step 120). In some embodiments, as described in more detail in, for example, U.S. Patent Nos. 7,727,588 and 8,252,375, the processing chamber can undergo one or more consecutive vacuum and nitrogen venting cycles to create a relatively oxygen-free and moisture-free environment within the processing chamber. In some embodiments, heated nitrogen can be used. For example, in some embodiments, the treatment chamber may be subjected to a vacuum (e.g., about 10 Torr for 2 minutes, etc.) and then to room temperature nitrogen or heated nitrogen (e.g., at 150°C), once or multiple times, to remove moisture and oxygen from the chamber. If heated nitrogen is used, the preheated nitrogen may also warm the surface of the substrate. In embodiments where it is desirable not to heat the substrate until the oxygen level drops below an acceptable level (e.g., <100 ppm), room temperature (or cooled) nitrogen may be used. The vapor of the desired chemical component (e.g., components listed in Table 1) may then be allowed into the treatment chamber (step 130). The chemical vapor injected into the chamber may be obtained by evaporating a liquid chemical component and then allowing it into the treatment chamber, or it may be transported by an inert carrier gas (e.g., nitrogen). For example, heated nitrogen may be bubbled through a liquid chemical component and then allowed into the treatment chamber. In some embodiments, the chemical vapor of step 130 may be obtained by evaporating a pure liquid chemical, or it may be obtained by evaporating a solid or semi-solid chemical. As previously described, the exposure time of the chemical vapors to the substrate can be varied depending on the reaction rate of the substrate to obtain a dense monolayer film. The temperature and pressure of the chamber can also be adjusted to maintain the chemical vapors in the gas phase. After the metal structure 10 has been exposed to the chemical vapors for a sufficient time, the chamber can be evacuated to remove excess chemical vapors (step 140). In some embodiments, similar to step 120, the treatment chamber can be subjected to vacuum and nitrogen one or more times to completely remove the chemical vapors from the chamber. In some embodiments, the chamber can then be vented to the atmosphere (step 150). After treating the metal structure 10 with the chemical vapors, an organic layer 20 can be formed on top of the treated metal structure 10 using any suitable process known in the art (e.g., deposition, etc.). In some embodiments, a conformal coating of the organic layer 20 can be deposited on the surface of the substrate having the metal structure 10.In step 130, the surface of the metal structure is treated with chemical vapor to produce a single layer of chemical coating 15 on the surface, which improves the adhesion of the organic layer to the metal surface.

[0031] In some implementations... Figure 2A The process can be used in processing apparatuses with preheated chambers. In other embodiments of the processing apparatus, the processing chamber and / or substrate can be heated from room temperature to the processing temperature (step 130) before exposure to chemical vapors, and then cooled to a temperature safe for exposure to atmospheric oxygen (typically <100°C). Such a process can be used to process oxygen-sensitive metals (e.g., copper). Figure 2B This is a flowchart of another exemplary process that can be used. Figure 2B and reference Figure 2A Similar process steps are similarly numbered and not described in detail. Figure 2B In process 100B, as referenced Figure 2A After the chamber is emptied as described (step 120), the processing chamber and / or substrate can be heated to the processing temperature (step 125). The processing temperature (e.g., 150°C, 175°C, 200°C, etc.) may depend on the processing apparatus used. The metal surface is then treated with vapor of the selected chemical composition (step 130). The substrate is then cooled to a safe unloading temperature, for example, below about 100°C (step 135). The chamber can then be vented (step 140) and vented (step 150). It should be noted that... Figure 2A and 2B The process shown is merely exemplary, and many modifications are possible. For example, the described steps can be performed in a different order, and some steps can be eliminated. For example, in Figure 2B In process 100B, steps 135 and 140 can be interchanged (e.g., step 140 can be performed before step 135). In some embodiments, processes 100A and 100B can be part of a larger process. For example, in some embodiments, process 100A or 100B can be incorporated into a process for depositing organic materials on a metal structure.

[0032] When the metal structure 10 is exposed to chemical vapors in step 130, a monolayer coating 15 of the chemical composition can be formed (or deposited) on the surface of the metal structure 10. Although the monolayer coating 15 can be bonded to the metal structure using any mechanism, in some embodiments where the metal structure 10 includes copper, the monolayer coating can be bonded to the metal structure 10 using one or more of the mechanisms listed in Table 2 below.

[0033] Table 2: Exemplary Combination Mechanisms

[0034]

[0035] The surface of the copper metal structure 10 can be populated with Cu atoms or CuO molecules, resulting in different bonding mechanisms as described above. A unique characteristic of the selected chemical composition is that it can form covalent bonds in oxidized regions or chelate bonds in regions where the native oxide has been removed and only copper remains. The orientation of the molecules can change from one point to another on the surface, but the molecules will still bond. In some embodiments, each of these selected molecules will utilize all bonding mechanisms at different locations on the surface.

[0036] Using the disclosed process to treat the surface of the metal structure 10 can improve the adhesion between the organic layer 20 and the metal structure 10 in the electronic device. Specifically, a single-layer coating 15 of chemical composition formed between the metal surface and the organic layer can improve the interfacial adhesion of the metal-organic interface. This improvement in adhesion can lead to a reduction (or elimination) of post-etching delamination from the top and sidewalls of the metal-organic interface, which causes interfacial failure and reliability issues in the electronic device. Since the improved adhesion is achieved without increasing the surface roughness of the metal structure 10, signal loss can also be eliminated.

[0037] Although the disclosed process is described with reference to electronic devices, it is merely exemplary. As those skilled in the art will recognize, embodiments of the disclosed method can also be used in other applications. For example, embodiments of the disclosed method can also be used to promote adhesion of metal-organic interfaces in devices used in drug delivery, drug absorption, gas separation, lithium-ion batteries, CO2 capture, medical sensors, biomarkers, wearable devices, etc. The disclosed processing method can be incorporated into any suitable processing equipment (e.g., processing furnace, vapor deposition system, coater, etc.). Furthermore, although some process steps have been disclosed with reference to specific embodiments in the above description, those skilled in the art will recognize that this is merely exemplary and that these steps are applicable to all disclosed embodiments. Other embodiments of the disclosed method will become apparent to those skilled in the art upon consideration of the disclosure herein.

Claims

1. Methods for improving the adhesion of metal-organic interfaces in electronic devices, including: A substrate is provided having a metallic structure formed thereon; The surface of the metal structure is treated with a vapor of a chemical component to form a single-layer coating of the chemical component on the surface of the metal structure, wherein the chemical component includes at least one of the following: (i.) 2-Hydroxyethyl methacrylate, (ii.) Vinylphosphonic acid, (iii.)N-[3-(dimethylamino)propyl]methacrylamide, (iv.) 2-(diethylamino)ethyl methacrylate, (v.) 2-(dimethylamino)ethyl methacrylate, (vi.) 2-Aminoethyl methacrylate hydrochloride, or (vii.) 2,3-glycidyl methacrylate; and After treating the surface of the metal structure, the treated surface is coated with an organic material, wherein the metal-organic interface between the treated surface of the metal structure and the coated organic layer has improved adhesion.

2. The method of claim 1, wherein the monolayer coating of the chemical component is about 1 to 10 angstroms thick.

3. The method according to claim 1, wherein the chemical component has a boiling point below about 250°C at a pressure between about 0.1 and 10 Torr.

4. The method of claim 1, wherein providing the substrate comprises providing the substrate in a processing chamber, and the method further comprises venting oxygen or moisture from the processing chamber prior to treating the surface of the metal structure with the vapor of the chemical composition.

5. The method of claim 4, further comprising, after treating the surface of the metal structure with the vapor of the chemical component, venting the vapor of the chemical component from the treatment chamber.

6. The method of claim 1, wherein the metal structure comprises copper.

7. The method of claim 6, wherein the organic material comprises parylene.

8. The method of claim 1, wherein the substrate is part of a packaging substrate.

9. The method of claim 1, wherein the metal structure is the interconnect structure of the electronic device.

10. The method of claim 9, wherein the interconnect structure is one of an interconnect line, a power plane, a ground plane, a via, or a plated through-hole.

11. Methods for improving the adhesion of metal-organic interfaces in electronic devices, including: Provide a substrate with a copper interconnect structure; The surface of the copper interconnect structure is treated with a vapor of a chemical component to form a single-layer coating of the chemical component on the surface of the copper interconnect structure, wherein the chemical component includes at least one of the following: (i.) 2-Hydroxyethyl methacrylate, (ii.) Vinylphosphonic acid, (iii.)N-[3-(dimethylamino)propyl]methacrylamide, (iv.) 2-(diethylamino)ethyl methacrylate, (v.) 2-(dimethylamino)ethyl methacrylate, (vi.) 2-Aminoethyl methacrylate hydrochloride, or (vii.) 2,3-glycidyl methacrylate; and After treating the surface of the copper interconnect structure, the treated surface is coated with parylene, wherein the metal-organic interface between the treated surface of the copper interconnect structure and the coated parylene has improved adhesion.

12. The method of claim 11, wherein coating the treated surface with parylene comprises depositing the parylene on the coated surface.

13. The method of claim 11, wherein the substrate is part of a packaging substrate, and the copper interconnect structure is one of an interconnect, a power plane, a ground plane, a via, or a plated through-hole.

14. The method of claim 11, wherein providing the substrate comprises providing the substrate in a processing chamber, and the method further comprises venting oxygen or moisture from the processing chamber prior to treating the surface of the copper interconnect structure with the vapor of the chemical composition.

15. The method of claim 14, further comprising, after treating the surface of the copper interconnect structure with the vapor of the chemical component, venting the vapor of the chemical component from the treatment chamber.

16. Electronic devices having a metal-organic interface, including: Substrate with a metallic structure; A single-layer coating of chemical composition formed on the surface of the metal structure, wherein the chemical composition includes at least one of the following: (i.) 2-Hydroxyethyl methacrylate, (ii.) Vinylphosphonic acid, (iii.)N-[3-(dimethylamino)propyl]methacrylamide, (iv.) 2-(diethylamino)ethyl methacrylate, (v.) 2-(dimethylamino)ethyl methacrylate, (vi.) 2-Aminoethyl methacrylate hydrochloride, or (vii.) 2,3-glycidyl methacrylate; and An organic material layer is disposed on the monolayer coating of the chemical composition.

17. The device of claim 16, wherein the monolayer coating of the chemical composition is about 1 to 10 angstroms thick.

18. The device of claim 16, wherein the monolayer coating of the chemical composition located between the metal structure and the organic material layer improves the adhesion of the metal-organic interface.

19. The device of claim 16, wherein the metal structure comprises copper and the organic material comprises parylene.

20. The device of claim 16, wherein the metal structure is one of an interconnect, a power plane, a ground plane, a via, or a plated through-hole.

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