JP2017130555A - Adhesion material, manufacturing method of circuit board and circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve adhesion between a barrier layer and an insulator layer.SOLUTION: The adhesion material for adhering a barrier layer covering a metal wiring and an insulator layer contains an organic compound having hydrogen bondability and a silane coupling agent.SELECTED DRAWING: Figure 10B

Description

  The present invention relates to an adhesive material, a circuit board manufacturing method, and a circuit board.

  In recent years, miniaturization and multilayering of printed wiring boards and high-density mounting of electronic components have rapidly progressed, and a buildup multilayer wiring structure has been studied for printed wiring boards. In the build-up multilayer wiring structure, an insulating layer is formed between a plurality of wiring layers, and the wiring layer and the insulating layer are laminated to form a highly integrated multilayer wiring board. However, adhesion between copper, which is a material of the wiring layer, and the insulating layer is low. Therefore, a technique for improving the adhesion due to the physical anchor effect is used. That is, the surface of the wiring layer is physically roughened to form irregularities on the surface of the wiring layer, and the insulating layer meshes with the irregularities, thereby improving the adhesion. In recent years, methods for improving the chemical adhesion between copper and components in the insulating layer have been studied.

Japanese Patent Laid-Open No. 10-335782 JP 2012-015405 A

  With the recent miniaturization of wiring, the width and interval of metal wiring are reduced. For this reason, the wiring current density increases, and the movement phenomenon (electromigration) of the wiring metal ions occurs. From the viewpoint of reliability, a barrier layer is formed on the metal wiring to suppress the occurrence of electromigration. However, if the barrier layer surface is sparse to improve the adhesion between the barrier layer and the insulating layer, the barrier layer may be lost because the thickness of the barrier layer is about 100 nm or less.

  This application aims at providing the technique which improves the adhesiveness of a barrier layer and an insulating layer.

  According to one aspect of the present application, there is provided an adhesive material that adheres a barrier layer covering a metal wiring and an insulating layer, and includes an organic compound having hydrogen bonding properties and a silane coupling agent. According to one aspect of the present application, a step of forming a metal wiring on a substrate, a step of forming a barrier layer covering the metal wiring, an organic compound having a hydrogen bonding property, and a silane coupling agent covering the barrier layer are included. There is provided a circuit board manufacturing method comprising a step of forming an adhesion layer and a step of forming an insulating layer covering the adhesion layer.

  According to the present application, the adhesion between the barrier layer and the insulating layer can be improved.

FIG. 1 is a diagram illustrating a combination of alkoxysilane, a hydrogen bonding organic compound, water, and an insulating material. FIG. 2 is a diagram illustrating a combination of alkoxysilane, a hydrogen bonding organic compound, water, and an insulating material. FIG. 3 is a diagram illustrating evaluation of adhesion between the barrier layer and the insulating layer. FIG. 4A is a cross-sectional view illustrating an example of the method of manufacturing the circuit board according to the embodiment in the order of steps. FIG. 4B is a cross-sectional view illustrating an example of the circuit board manufacturing method according to the embodiment in the order of steps. FIG. 4C is a cross-sectional view illustrating an example of the circuit board manufacturing method according to the embodiment in the order of steps. FIG. 5A is a cross-sectional view illustrating an example of the method of manufacturing the circuit board according to the embodiment in the order of steps. Drawing 5B is a sectional view showing an example of a manufacturing method of a circuit board concerning an embodiment in order of a process. Drawing 5C is a sectional view showing an example of a manufacturing method of a circuit board concerning an embodiment in order of a process. FIG. 6A is a cross-sectional view illustrating an example of the method of manufacturing the circuit board according to the embodiment in the order of steps. FIG. 6B is a cross-sectional view illustrating an example of the circuit board manufacturing method according to the embodiment in the order of steps. FIG. 6C is a cross-sectional view illustrating an example of the circuit board manufacturing method according to the embodiment in the order of steps. FIG. 7A is a cross-sectional view illustrating an example of the method of manufacturing the circuit board according to the embodiment in the order of steps. Drawing 7B is a sectional view showing an example of a manufacturing method of a circuit board concerning an embodiment in order of a process. FIG. 8A is a cross-sectional view illustrating an example of the method of manufacturing the circuit board according to the embodiment in the order of steps. FIG. 8B is a cross-sectional view illustrating an example of the circuit board manufacturing method according to the embodiment in the order of steps. FIG. 9A is a cross-sectional view illustrating an example of the method of manufacturing the circuit board according to the embodiment in the order of steps. FIG. 9B is a cross-sectional view illustrating an example of the circuit board manufacturing method according to the embodiment in the order of steps. FIG. 10A is a cross-sectional view illustrating an example of the method of manufacturing the circuit board according to the embodiment in the order of steps. FIG. 10B is a cross-sectional view illustrating an example of the circuit board manufacturing method according to the embodiment in the order of steps. FIG. 11A is a cross-sectional view illustrating another example of the method for manufacturing the circuit board according to the embodiment in the order of steps. FIG. 11B is a cross-sectional view illustrating another example of the method for manufacturing the circuit board according to the embodiment in the order of steps. FIG. 11C is a cross-sectional view illustrating another example of the circuit board manufacturing method according to the embodiment in the order of steps. FIG. 11D is a cross-sectional view illustrating another example of the circuit board manufacturing method according to the embodiment in the order of steps. FIG. 11E is a cross-sectional view illustrating another example of the method for manufacturing the circuit board according to the embodiment in the order of steps. FIG. 11F is a cross-sectional view illustrating another example of the circuit board manufacturing method according to the embodiment in the order of steps.

Hereinafter, an adhesive material, a circuit board manufacturing method, and a circuit board according to embodiments will be described with reference to the drawings. The following adhesive material, circuit board manufacturing method, and circuit board configuration are exemplary, and the present invention is not limited to the adhesive material, circuit board manufacturing method, and circuit board configuration according to the embodiment.

<Adhesive materials>
The adhesion material adheres the barrier layer covering the metal wiring and the insulating layer. Since the adhesion between the barrier layer and the insulating layer is low, the adhesion between the barrier layer and the insulating layer improves the adhesion between the barrier layer and the insulating layer. Therefore, the adhesion material is also called an adhesion improving material. The barrier layer is an inorganic material such as a metal. The insulating layer may be an organic material or an inorganic material.

  The adhesion material includes an organic compound having hydrogen bonding properties and a silane coupling agent. A silane coupling agent is an organosilicon compound having two types of functional groups having reactivity in the molecule. That is, the silane coupling agent has a hydrolyzable group (for example, an alkoxy group) and a functional group having a polarity capable of reacting with various functional groups. The hydrolyzable group is hydrolyzed with water to generate a hydroxyl group. For example, the hydroxyl group of the silane coupling agent and the hydroxyl group on the surface of the barrier layer are hydrogen bonded, so that the silane coupling agent and the barrier layer are in close contact with each other. Since the adhesive material includes an organic compound having hydrogen bonding properties and a silane coupling agent, the silane coupling agent and the barrier layer are connected via, for example, an organic compound having hydrogen bonding properties.

  The organic compound having hydrogen bonding property has one or more of any two or more of C═O, C—O, O—H and N—H in the molecule, or C═O in the molecule. , C—O, O—H, and N—H. That is, an organic compound having hydrogen bonding properties has at least two hydrogen bonding groups. One hydrogen bonding group of the organic compound is hydrogen bonded to the hydroxyl group of the silane coupling agent, and the other hydrogen bonding group of the organic compound is hydrogen bonded to the hydroxyl group on the surface of the barrier layer. Therefore, for example, the adhesion between the silane coupling agent and the barrier layer is improved through an organic compound having hydrogen bonding properties.

  The organic compound having hydrogen bonding property is at least one compound selected from polyphenols, dextrins, monosaccharides, urea compounds and amino acid compounds. Therefore, the adhesion material may have one or more of polyphenols, dextrins, monosaccharides, urea compounds and amino acid compounds. The adhesion material is preferably a solution containing water. Polyphenols, dextrins, monosaccharides, urea compounds and amino acid compounds are all water-soluble compounds.

  Polyphenols have C═O, C—O, and O—H as functional groups in the basic skeleton structure. Polyphenols have at least two OH in the basic skeleton structure. Dextrins have C—O and O—H as functional groups in the basic skeleton structure. Dextrins have at least two OH in the basic skeleton structure. The monosaccharide has C═O, C—O, and OH as functional groups in the basic skeleton structure. Monosaccharides have at least two OH in the basic skeleton structure. The urea compound has N—H and C═O as functional groups in the basic skeleton structure. The urea compound has at least two NH in the basic skeleton structure. The amino acid compound has C═O, C—O, O—H and N—H as functional groups in the basic skeleton structure. The amino acid compound has at least two OH in the basic skeleton structure. In addition, polyphenols, dextrins, monosaccharides, urea compounds and amino acid compounds are not basic skeletons, but include at least one of C═O, C—O, O—H and N—H as substituents and derivatives. The compound which has as a functional group may be sufficient. Therefore, polyphenols, dextrins, monosaccharides, urea compounds, and amino acid compounds each have one or more of any of C═O, C—O, O—H, and N—H in the molecule. . Alternatively, polyphenols, dextrins, monosaccharides, urea compounds, and amino acid compounds have two or more of any one of C═O, C—O, O—H, and N—H in the molecule.

  It is presumed that the functional group having polarity in the silane coupling agent (polar functional group) and the polar group of the insulating layer are hydrogen bonded, whereby the silane coupling agent and the insulating layer are in close contact with each other. Since the adhesion material has an organic compound having hydrogen bonding properties and a silane coupling agent, the polar functional group of the silane coupling agent and the polar group of the insulating layer are interposed through the organic compound having hydrogen bonding properties. Is estimated to be connected. It is presumed that one hydrogen bonding group of the organic compound hydrogen bonds with the polar functional group of the silane coupling agent, and the other hydrogen bonding group of the organic compound hydrogen bonds with the polar group of the insulating layer. Therefore, the adhesion between the silane coupling agent and the insulating layer is improved through the organic compound having hydrogen bonding properties.

  The silane coupling agent is preferably an alkoxysilane having at least one selected from a vinyl group, amino group, ureido group, mercapto group, methacryloxy group, acryloxy group, isocyanate group, imidazole group and epoxy group as a functional group. . The vinyl group, amino group, ureido group, mercapto group, methacryloxy group, acryloxy group, isocyanate group, imidazole group and epoxy group have polarity.

  The concentration of the monomer of the silane coupling agent in the aqueous solution is preferably 0.1 vol% or more and 20 vol% or less, and more preferably 0.5 vol% or more and 10 vol% or less. When the concentration of the monomer of the silane coupling agent in the aqueous solution is less than 0.1 vol%, the adhesion is reduced. When the concentration of the monomer of the silane coupling agent in the aqueous solution exceeds 20 vol%, the adhesion layer formed by the adhesion material becomes thick and the adhesion strength is reduced.

  The ratio of the organic compound to the silane coupling agent varies depending on the type of the organic compound, but is generally preferably 0.1 wt% or more and 50% or less, and more preferably 1 wt% or more and 20 wt% or less. When the ratio of the organic compound to the silane coupling agent is less than 0.1 wt%, the adhesion strength is reduced. When the ratio of the organic compound with respect to the silane coupling agent exceeds 20 wt%, adhesion of foreign matters due to precipitation occurs.

  The solvent of the adhesive material is preferably pure water, but alcohols may be added for the purpose of improving wettability. For example, methanol or ethanol may be added to pure water. The amount of alcohol added to the pure water is, for example, not less than 0.1 wt% and not more than 10 wt%. A silane coupling agent and an organic compound are dissolved in these solvents, and a sufficiently stirred aqueous solution is used as the adhesion material. Depending on the type of silane coupling agent, the silane coupling agent may contain alcohol from the beginning for stability. In addition, the silane coupling agent may contain an alcohol that is generated unintentionally because the alkoxy group of the silane coupling agent is hydrolyzed with moisture in the air. Alcohol added for stability or unintentionally generated alcohol is not included in the above-mentioned added alcohol.

<Processing method>
Examples of the method for treating the adhesive material for the substrate to be treated include an immersion method, a spray method, a spin coating method, and a vapor method. In the substrate to be processed, metal wiring is formed on the substrate to be processed, and a barrier layer that covers the metal wiring is formed. The dipping method is a method in which the substrate to be processed is immersed in the adhesive material for a certain period of time. The substrate to be processed is kept stationary or movable during the immersion. The immersion time can be appropriately selected depending on the state of the substrate to be processed, but is preferably 5 seconds or more and 600 seconds or less, more preferably 10 seconds or more and 300 seconds or less. When immersion time is a short time, possibility that sufficient effect will not be acquired becomes high. When the immersion time is long, it becomes inefficient due to excess of the process time.

In the spray method and the spin coating method, an adhesion material is applied to a substrate to be processed. It is preferable to optimize the conditions so that the substrate to be processed is processed uniformly according to the processing technique of each processing apparatus. In any of the treatment methods, it is preferable to fix the adhesion material at a constant temperature of 20 ° C. or more and 100 ° C. or less in consideration of the stability of the reaction of the adhesion material, and the adhesion material is fixed temperature of 30 ° C. or more and 70 ° C. or less. It is more preferable to fix to.

  An adhesion material is formed on the barrier layer by dipping, spraying, spin coating or vapor. After the adhesion material is formed on the barrier layer, a rinsing process using water or water containing alcohol may be performed. However, the rinsing process is not essential. When the rinse treatment is performed, a dipping method in which the substrate to be treated is immersed in running water, a large amount of pool water, or a circulated water bath can be used, and the surface of the adhesion material can be efficiently cleaned. Since the rinse treatment is not essential, there is no lower limit to the treatment time of the rinse treatment. The upper limit of the treatment time for the rinse treatment is preferably approximately 600 seconds or less, and more preferably 300 seconds or less. When the processing time of the rinsing process is long, it becomes inefficient due to excess of the process time.

  Even if spray rinsing processing and spin coating rinsing processing are performed on the substrate to be processed using the apparatus used in the spray method and spin coating method, sufficient rinsing is possible. The treatment time for the spray rinsing treatment and the spin coat rinsing treatment is the same as in the dipping method, and there is no lower limit of the treatment time, and the upper limit of the treatment time is preferably 600 seconds or less, more preferably 300 seconds or less. When rinsing is performed, the liquid used for rinsing is preferably fixed at a constant temperature of 20 ° C. or higher and 100 ° C. or lower, and the adhesive material is fixed at a constant temperature of 30 ° C. or higher and 70 ° C. or lower, similar to the adhesive material. Is more preferable.

  You may perform a drying process and heat processing suitably at the time of the formation of the contact | adherence material with respect to a barrier layer, or after formation. By performing the drying treatment and the heat treatment, improvement and stabilization of the reactivity of the adhesive material with respect to the barrier layer can be expected. The drying process is a process for removing droplets on the surface of the adhesive material by blowing nitrogen gas or the like on the surface of the adhesive material or by spin-off. The heat treatment is preferably a treatment for removing droplets with a hot plate or an oven. The treatment temperature of the heat treatment is preferably 60 ° C. or higher and 150 ° C. or lower. The treatment time for the heat treatment is preferably 10 seconds or more and 300 seconds or less.

<Barrier layer>
The barrier layer is, for example, CoWP, NiP, CoWB, CoP, CoB, NiWP, NiB, and NiWB. The thickness of the barrier layer is, for example, 5 nm or more and 200 nm or less.

<Insulating material>
Examples of the insulating material forming the insulating layer include organic materials and inorganic materials. An organic material and an inorganic material will not be specifically limited if it is the material formed by application | coating, sticking, or CVD (Chemical Vapor Deposition) method. Examples of the coating type or sticking type material include polyimide resin, epoxy resin, bismaleimide resin, maleimide resin, cyanate resin, phenol resin, urethane resin, novolac resin, acrylic resin, methacrylic resin, polyphenylene ether resin, polyphenylene oxide resin, Examples thereof include insulating resin materials such as polyolefin resin, fluorine-containing resin, liquid crystal polymer, polyetherimide resin, polyether ether ketone resin, and polyallyl ether resin. In addition, examples of the coating material include inorganic SOG (Spin On Glass) having a Si—O skeleton, organic SOG having an organic group therein, and low-k material having pores. Examples of the CVD type material include oxides, nitrides, and fluorides of metals such as SiO ₂ , SiOF, SiN, SiON, SiC, SiOC, Al ₂ O ₃ , and AlN, and these are not particularly limited. It is also possible to use the organic insulating material and the inorganic insulating material as separate layers at the same time.

  Further, an adhesive material may be interposed between the metal wiring and the insulating layer. Adhesion between the metal wiring and the insulating layer improves the adhesion between the metal wiring and the insulating layer.

Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited to these examples.
<Preparation of adhesive material 1>
To 970 mL of pure water adjusted to pH 3.2 with acetic acid, 30 g of 3-glycidoxypropyltrimethoxysilane (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) and urea (manufactured by Wako Pure Chemical Industries, Ltd.) 4.5 g was dissolved. For example, it was stirred in a water bath at 40 ° C. for 1 hour to produce a solution of the adhesive material. A substrate having a Cu wiring formed by Cu (copper) plating and a NiP barrier layer formed on the Cu wiring by electroless plating was prepared, and the substrate was immersed in an adhesive material solution for 180 seconds. Next, the substrate was lifted from the solution of the adhesive material and rinsed using a water bath in which water was circulated. Further, nitrogen gas was blown onto the surface of the NiP barrier layer to dry the surface of the NiP barrier layer, thereby forming an adhesion layer on the NiP barrier layer. Next, an insulating material mainly composed of a phenol resin was applied by a spin coating method. Next, for example, the insulating material was thermally cured at 230 ° C. for 1 hour in an oven in a nitrogen atmosphere. Thereby, for example, an insulating layer having a thickness of 5 μm was formed on the NiP barrier layer covering the metal wiring via the adhesion layer.

<Preparation of adhesive material 2>
The following (1) alkoxysilane, (2) an organic compound having hydrogen bonding properties (hydrogen bonding organic compound), (3) water, and (4) an insulating material were prepared.
(1) Alkoxysilane Compound I: 3-Glycidoxypropyltrimethoxysilane Compound II: 3-aminopropyltrimethoxysilane Compound III: N-2- (aminoethyl) -3-aminopropyltrimethoxysilane Compound IV: 3 -Ureidopropyltriethoxysilane (2) Hydrogen bonding organic compound Compound A: Urea Compound B: Dihydroxyphenyl-L-alanine (3) Water Water (with pH adjustment): Pure adjusted to pH 3.2 with acetic acid Water Water (without pH adjustment): Pure water without pH adjustment (4) Insulating material (main material)
Epoxy: Insulating material mainly composed of epoxy resin Phenol: Insulating material mainly composed of epoxy resin Urethane: Insulating material mainly composed of urethane resin Acrylic: Based on acrylic resin Insulation material

  Using the above (1) alkoxysilane, (2) hydrogen-bonding organic compound, and (3) water, a solution of the adhesive material was produced in the same manner as in Preparation 1 of the adhesive material. Further, an insulating layer was formed on the NiP barrier layer covering the metal wiring via the adhesive layer by the method shown in Preparation 1 of the adhesive material, using the above (4) insulating material (main material). 1 and 2, the combination of (1) alkoxysilane, (2) hydrogen-bonding organic compound, (3) water and insulating material (main material), (1) alkoxysilane, and (2) hydrogen bond. The mass (g) of the water-soluble organic compound and (3) water is shown.

As shown in FIG.1 and FIG.2, in Examples 1-25, the kind of alkoxysilane, the kind of hydrogen bonding organic compound, the mass of alkoxysilane, the mass of hydrogen bonding organic compound, and the mass of water were changed. The adhesion material is prepared. In Examples 1 to 25 shown in FIGS. 1 and 2,
The insulating layer is formed by changing the type of the insulating material (main material). In Comparative Example 1 shown in FIG. 2, an insulating layer is formed on the NiP barrier layer without using an adhesion layer. In Comparative Example 2 shown in FIG. 2, the adhesion material is prepared without using the hydrogen bonding organic compound, and the insulating layer is formed on the NiP barrier layer via the adhesion layer. In Comparative Examples 3 and 4 shown in FIG. 2, the adhesion material is prepared without using alkoxysilane, and the insulating layer is formed on the NiP barrier layer via the adhesion layer.

  About Examples 1-25 and Comparative Examples 1-4 shown in FIG.1 and FIG.2, the adhesiveness of a NiP barrier layer and an insulating layer was evaluated. Peel strength measurement was performed to evaluate the adhesion between the NiP barrier layer and the insulating layer. The results of peel strength measurement are shown in FIG. As shown in FIG. 3, compared to the peel strength value when the adhesion layer was not formed (see Comparative Example 1), the adhesion material was prepared using an alkoxysilane and a hydrogen bonding organic compound. The peel strength value (see Examples 1 to 25) is large. As shown in FIG. 3, the peel strength value (see Examples 1 to 25) when the adhesion material is prepared using alkoxysilane and a hydrogen bonding organic compound is 0.36 kgf / cm or more. Thus, it can also confirm from the result of a peel strength measurement that the adhesiveness of a NiP barrier layer and an insulating layer improves by preparing an adhesive material using an alkoxysilane and a hydrogen bondable organic compound.

  On the other hand, as shown in FIG. 3, the peel strength value (see Comparative Examples 3 and 4) when the adhesion material is prepared without using alkoxysilane is the peel strength when the adhesion layer is not formed. There is almost no change from the value (see Comparative Example 1), and the adhesion between the NiP barrier layer and the insulating layer is not improved. Moreover, as shown in FIG. 3, compared with the value of the peel strength (see Examples 1 to 25) when the adhesion material is prepared using an alkoxysilane and a hydrogen bonding organic compound, the hydrogen bonding organic compound is used. The degree of increase in the peel strength value (see Comparative Example 2) when the adhesive material is prepared without using is small.

  In the peel strength measurement, a measurement sample was measured at a speed of about 50 mm / mm using a device in which a force gauge (manufactured by Imada, product name: DPX-5TR) was installed in a 90 ° peel tester (manufactured by Nisshin Kagaku). The peel strength when peeled vertically in min was measured. As a measurement sample, a NiP barrier layer, an adhesion layer, and an insulating layer are formed on a CCL substrate A on which Cu plating is formed on a peelable Cu foil in accordance with the procedure of <Adhesion material preparation 1>, and further thermosetting. In this sample, the CCL substrate A is peeled off after forming the conductive dry film and the CCL substrate B. The peelable Cu foil is exposed by peeling the CCL substrate A at the interface of the peelable Cu foil. The pulling strength can be measured by pulling the exposed peelable Cu foil. The CCL substrate is a laminated substrate for a printed circuit board in which a base material such as a glass cloth is impregnated with an insulating resin such as an epoxy resin and a copper foil is bonded and laminated.

<Method for manufacturing circuit board>
An example of a method for manufacturing a circuit board (wiring structure) according to the embodiment will be described. 4A to 10B are cross-sectional views illustrating an example of a circuit board manufacturing method according to the embodiment in the order of steps. Below, the manufacturing method of the circuit board using a semi-additive method is shown.

First, as shown in FIG. 4A, a base insulating film 22 is formed on the substrate 21. In the present embodiment, a semiconductor substrate such as a silicon substrate is used as the substrate 21, but a substrate such as a resin or ceramic may be used. The base insulating film 22 may be a thermal oxide film formed by thermally oxidizing the surface of a silicon substrate, or may be an insulating film formed by a CVD (Chemical Vapor Deposition) method or the like.

Next, as shown in FIG. 4B, a metal adhesion layer 23 is formed on the base insulating film 22 to a thickness of, for example, 5 nm or more and 20 nm or less. The metal adhesion layer 23 is, for example, a metal or a compound such as Ti (titanium). The metal adhesion layer 23 has a function of firmly bonding a Cu wiring 26 and a base insulating film 22 described later, and a function as a barrier film that suppresses diffusion of metal atoms (Cu) from the Cu wiring 26 to the base insulating film 22. And have. After the formation of the metal adhesion layer 23, the plating seed layer 24 is formed on the metal adhesion layer 23 to a thickness of 10 nm or more and 200 nm or less by, for example, sputtering. The plating seed layer 24 is, for example, Cu.

  Next, as shown in FIG. 4C, a photoresist film 25 is formed on the plating seed layer 24, and the photoresist film 25 is exposed and developed to form openings 25A where the plating seed layer 24 is exposed in a predetermined pattern. (Wiring pattern). The width of the opening 25A is about 2 μm. Next, as shown in FIG. 5A, for example, Cu having a thickness of 2 μm is plated on the plating seed layer 24 inside the opening 25A by an electrolytic plating method or an electroless plating method, and a Cu wiring 26 is formed. Form. That is, the Cu wiring 26 is formed on the substrate 21. The Cu wiring 26 is an example of a metal wiring.

  Next, as shown in FIG. 5B, the photoresist film 25 is removed by, for example, resist stripping solution or ashing. Further, as shown in FIG. 5C, the plating seed layer 24 and the metal adhesion layer 23 which are not covered with the Cu wiring 26 are removed by etching. The plating seed layer 24 is etched using, for example, potassium sulfide. The metal adhesion layer 23 is etched using, for example, ammonium fluoride.

Next, the surface (upper surface and side surface) of the Cu wiring 26 is acid cleaned using, for example, an aqueous solution of H ₂ SO ₄ (sulfuric acid). By this acid cleaning, the surface of the Cu wiring 26 is activated. Thereafter, the substrate 21 is immersed in an activation treatment liquid containing Pd (palladium) (for example, an acidic liquid containing palladium chloride as a main component). As a result, the surface of the Cu wiring 26 is activated.

  Next, a metal such as CoWP or NiP is deposited on the surface (side surface and top surface) of the Cu wiring 26 by electroless plating, and the surface (side surface and top surface) of the Cu wiring 26 is shown in FIG. 6A. The barrier layer 27 is formed. That is, a barrier layer 27 that covers the Cu wiring 26 is formed. The thickness of the barrier layer 27 is, for example, not less than 10 nm and not more than 200 nm. The barrier layer 27 is formed of a metal that has high adhesion to the Cu wiring 26 and that can prevent the intrusion of moisture and oxygen and the diffusion of Cu. Suitable metals for the barrier layer 27 include CoWB, CoP, CoB, NiWP, NiB, and NiWB in addition to the aforementioned CoWP and NiP.

  Next, after the substrate 21 is immersed in the adhesive material, the substrate 21 is pulled up from the adhesive material and is subjected to a drying process or the like, thereby forming an adhesive layer 28 that covers the barrier layer 27 as shown in FIG. 6B. The adhesion layer 28 may be formed not only by the dipping method but also by a spray method, a spin coating method or a vapor method. The adhesion layer 28 includes an organic compound having hydrogen bonding properties and a silane coupling agent.

  Next, as shown in FIG. 6C, an insulating layer (insulating film) 29 is formed with a thickness of, for example, 5 μm on the substrate 21 by, eg, CVD. That is, an insulating layer 29 that covers the adhesion layer 28 is formed. Thus, the wiring structure according to the present embodiment is formed, and the first wiring layer including the Cu wiring 26, the barrier layer 27, the adhesion layer 28, the insulating layer 29, and the like is formed on the substrate 21.

Next, a hole reaching the predetermined Cu wiring 26 from the surface of the insulating layer 29 is formed by performing photolithography and dry etching. Next, as shown in FIG. 7A, a metal adhesion layer 31 and a plating seed layer 32 are sequentially formed in the holes formed in the insulating layer 29. The metal adhesion layer 31 is, for example, a metal such as Ti or a compound. The plating seed layer 32 is, for example, Cu. Next, as shown in FIG. 7B, a photoresist film 33 is formed on the plating seed layer 32.
Then, the photoresist film 33 is exposed and developed to form an opening 33A where the plating seed layer 32 is exposed in a predetermined pattern.

  Next, as shown in FIG. 8A, Cu is plated on the plating seed layer 32 inside the opening 33A to a thickness of 2 μm, for example, to form a Cu wiring. That is, the Cu wiring 34 is formed on the substrate 21. The Cu wiring 34 is an example of a metal wiring. Thereafter, as shown in FIG. 8B, the photoresist film 33 is removed by, for example, a resist stripping solution or ashing. Next, as shown in FIG. 9A, the plating seed layer 32 and the metal adhesion layer 31 that are not covered by the Cu wiring 34 are removed by etching. The plating seed layer 32 is etched using, for example, potassium sulfide. The metal adhesion layer 31 is etched using, for example, ammonium fluoride.

  Next, the surface (side surface and upper surface) of the Cu wiring 34 is activated by acid cleaning, and then the substrate 21 is immersed in an activation treatment solution to activate the surface of the Cu wiring 34. Next, as shown in FIG. 9B, a barrier layer 35 is formed on the surface of the Cu wiring 34 by an electroless plating method or the like. That is, a barrier layer 35 that covers the Cu wiring 34 is formed. The thickness of the barrier layer 35 is, for example, not less than 10 nm and not more than 200 nm. The barrier layer 35 is formed of a metal that has high adhesion to the Cu wiring 34 and can suppress the intrusion of moisture and oxygen and the diffusion of Cu. Suitable metals for the barrier layer 35 include CoWB, CoP, CoB, NiWP, NiB, and NiWB in addition to the aforementioned CoWP and NiP.

  Next, after the substrate 21 is immersed in the adhesive material, the substrate 21 is pulled up from the adhesive material and is subjected to a drying process or the like, thereby forming an adhesive layer 36 that covers the barrier layer 35 as shown in FIG. 10A. The adhesion layer 36 may be formed not only by the dipping method but also by a spray method, a spin coat method, or a vapor method. The adhesion layer 36 includes an organic compound having hydrogen bonding properties and a silane coupling agent.

  Next, as illustrated in FIG. 10B, an insulating layer (insulating film) 37 is formed on the substrate 21 with a thickness of, for example, 5 μm by, for example, a CVD method. That is, the insulating layer 37 that covers the adhesion layer 36 is formed. Thus, the wiring structure according to the present embodiment is formed, and the second wiring layer having the Cu wiring 34, the barrier layer 35, the adhesion layer 36, the insulating layer 37, and the like is formed on the substrate 21. Moreover, you may form a 3rd wiring layer, a 4th wiring layer, ... by the formation method similar to a 2nd wiring layer. Thus, the multilayer wiring structure of the semiconductor device according to this embodiment is completed, and the circuit board (multilayer wiring board) according to this embodiment is manufactured.

  According to the adhesion material, the circuit board manufacturing method, and the circuit board according to the embodiment, the adhesion between the barrier layer covering the metal wiring and the insulating layer can be improved. For example, the adhesion between the barrier layer 27 and the insulating layer 29 can be improved by forming the adhesion layer 28 between the barrier layer 27 covering the Cu wiring 26 and the insulating layer 29. Further, for example, by forming the adhesion layer 36 between the barrier layer 35 covering the Cu wiring 34 and the insulating layer 37, the adhesion between the barrier layer 35 and the insulating layer 37 can be improved. Thereby, a highly reliable circuit board (laminated body) can be manufactured, and further, a circuit board can be manufactured with a high yield.

  Next, another example of the method for manufacturing the circuit board (wiring structure) according to the embodiment will be described. 11A to 11F are cross-sectional views showing another example of a method of manufacturing a circuit board (wiring structure) in the order of steps, and show an example applied to an LSI wiring structure. In this method, Cu wiring is used as the metal wiring.

First, steps required until a wiring structure shown in FIG. 11A is obtained. First, the element isolation film 52 and the transistor 53 are formed on the substrate 51 by a known method. In the present embodiment, a semiconductor substrate such as a silicon substrate is used as the substrate 51, but a substrate such as a resin or ceramic may be used. Thereafter, an insulating layer (insulating film) 54 covering the element isolation film 52 and the transistor 53 and a protective layer 55 thereon are formed on the substrate 51. Here, the insulating layer 54 is, for example, silicon oxide, and the thickness of the insulating layer 54 is, for example, 300 nm. The protective layer 55 is, for example, SiOC, and the thickness of the protective layer 55 is, for example, 50 nm.

Next, a via hole reaching the transistor 53 from the upper surface of the protective layer 55 is formed in the insulating layer 54 by using a photolithography method and an etching method. Next, a barrier layer 56 is formed to a thickness of 25 nm on the entire upper surface of the substrate 51 by sputtering, for example, and the inside of the via hole is covered with the barrier layer 56. The barrier layer 56 is, for example, TiN. Thereafter, a W (tungsten) film is formed on the entire upper surface of the substrate 51 by CVD or the like, and W is buried in the via hole to form a W plug 57. Next, the W film and the barrier layer 56 on the protective layer 55 are exposed by, for example, CMP (Chemical Mechanical Polishing) until the protective layer 55 is exposed.
Remove. In this way, the wiring structure shown in FIG. 11A is obtained.

  Next, steps required until a wiring structure shown in FIG. After forming the W plug 57 in the above-described process, an insulating layer (insulating film) 58 is formed to a thickness of, for example, 300 nm by depositing silicon oxide or the like on the protective layer 55 and the W plug 57. Next, wiring grooves are formed in a desired pattern (wiring pattern) in the insulating layer 58 by using a photolithography method and an etching method. Thereafter, a barrier layer 59 is formed on the entire upper surface of the substrate 51 to a thickness of, for example, 5 nm to 20 nm, and a plating seed layer (not shown) is formed on the barrier layer 59 to a thickness of 50 nm to 200 nm. The barrier layer 59 is, for example, Ta (tantalum). The plating seed layer on the barrier layer 59 is, for example, Cu. Next, a Cu film is formed on the plating seed layer by electrolytic plating, and Cu wiring 60 is formed by embedding Cu in the wiring groove. Next, the Cu film, the plating seed layer, and the barrier layer 59 on the insulating layer 58 are removed by CMP until the insulating layer 58 is exposed. In this way, the wiring structure shown in FIG. 11B is obtained. The Cu wiring 60 is an example of a metal wiring.

  Next, as shown in FIG. 11C, NiP or CoWP is electrolessly plated on the Cu wiring 60 to form a barrier layer (metal cap layer) 61 on the Cu wiring 60.

  Next, the laminate shown in FIG. 11C is immersed in the adhesive material, and an adhesive layer 62 is formed on the surface of the barrier layer 61 as shown in FIG. 11D. The adhesion layer 62 includes a compound layer and a metal oxide layer from the barrier layer 61 side.

  Next, steps required until a wiring structure shown in FIG. After the adhesion layer 62 is formed in the above-described process, an insulating layer (insulating film) 63, a stopper film 64, an insulating layer (insulating film) 65, and a stopper film 66 are sequentially formed on the entire upper surface of the substrate 51. Here, the insulating layers 63 and 65 are silicon oxide, and the stopper films 64 and 66 are silicon nitride. Thereafter, a wiring trench 65A having a depth reaching the stopper film 64 from the upper surface of the stopper film 66 is formed in the insulating layer 65 by using a photolithography method and an etching method, and the Cu wiring 60 and the barrier layer are formed from the upper surface of the stopper film 64. A via hole 63 </ b> A reaching 61 is formed in the insulating layer 63. In this way, the wiring structure shown in FIG. 11E is obtained.

Next, steps required until a structure shown in FIG. 11F is formed will be described. After forming the wiring trench 65A and the via hole 63A in the above-described process, a barrier layer 67 and a plating seed layer (not shown) are sequentially formed on the entire upper surface of the substrate 51. The barrier layer 67 is, for example, NiP or CoWP. The plating seed layer on the barrier layer 67 is, for example, Cu. Thereafter, a Cu film is formed on the plating seed layer by electrolytic plating, and Cu is embedded in the via hole 63A and the wiring groove 65A. Thereby, the Cu wiring 69 (second Cu wiring), the Cu wiring 60 (first Cu wiring), and the via contact 68 that electrically connects the Cu wiring 69 are formed. Next, the Cu film, the plating seed layer, and the barrier layer 67 on the stopper layer 66 are removed by CMP until the stopper layer 66 is exposed. Next, similarly to the Cu wiring 60, NiP or CoWP is electrolessly plated on the Cu wiring 69 to form a barrier layer (metal cap layer) 70. Thus, the multilayer wiring structure of the semiconductor device according to this embodiment is completed, and the circuit board (multilayer wiring board) according to this embodiment is manufactured.

  According to the adhesion material, the circuit board manufacturing method, and the circuit board according to the embodiment, the adhesion between the barrier layer covering the metal wiring and the insulating layer can be improved. For example, the adhesion between the barrier layer 61 and the insulating layer 63 can be improved by forming the adhesion layer 62 between the barrier layer 61 covering the Cu wiring 60 and the insulating layer 63. Thereby, a highly reliable circuit board (laminated body) can be manufactured, and further, a circuit board can be manufactured with a high yield.

  As mentioned above, although this embodiment was explained in full detail, this invention is not limited to specific embodiment, A various deformation | transformation and change are possible within the range of the summary of this invention described in the claim. It is.

Regarding the embodiment including the above-described examples, the following additional notes are further shown.
(Appendix 1)
An adhesion material that adheres the barrier layer covering the metal wiring and the insulating layer,
An organic compound having hydrogen bonding properties;
A silane coupling agent;
A contact material characterized by containing.
(Appendix 2)
The organic compound having hydrogen bonding property has one or more of any two or more of C═O, C—O, O—H and N—H in the molecule, or C in the molecule. = Having two or more of any one of O, C—O, O—H, and N—H,
The adhesive material according to Supplementary Note 1, wherein:
(Appendix 3)
The organic compound having hydrogen bonding property is at least one compound selected from polyphenols, dextrins, monosaccharides, urea compounds and amino acid compounds.
The adhesion material according to appendix 1 or 2, characterized in that:
(Appendix 4)
The silane coupling agent is an alkoxysilane having at least one selected from a vinyl group, amino group, ureido group, mercapto group, methacryloxy group, acryloxy group, isocyanate group, imidazole group and epoxy group as a functional group.
The adhesion material according to any one of claims 1 to 3, wherein
(Appendix 5)
Forming metal wiring on the substrate;
Forming a barrier layer covering the metal wiring;
Covering the barrier layer and forming an adhesion layer containing a hydrogen bonding organic compound and a silane coupling agent;
Forming an insulating layer covering the adhesion layer;
A method of manufacturing a circuit board, comprising:
(Appendix 6)
The organic compound having hydrogen bonding property has one or more of any two or more of C═O, C—O, O—H and N—H in the molecule, or C in the molecule. = Having two or more of any one of O, C—O, O—H, and N—H,
The method for manufacturing a circuit board according to appendix 5, wherein:
(Appendix 7)
The organic compound having hydrogen bonding property is at least one compound selected from polyphenols, dextrins, monosaccharides, urea compounds and amino acid compounds.
The method for manufacturing a circuit board according to appendix 5 or 6, wherein:
(Appendix 8)
The silane coupling agent is an alkoxysilane having at least one selected from a vinyl group, amino group, ureido group, mercapto group, methacryloxy group, acryloxy group, isocyanate group, imidazole group and epoxy group as a functional group.
The method for manufacturing a circuit board according to any one of appendices 5 to 7, wherein:
(Appendix 9)
A substrate,
Metal wiring formed on the substrate;
A barrier layer covering the metal wiring;
An adhesive layer covering the barrier layer and containing an organic compound having a hydrogen bonding property and a silane coupling agent;
An insulating layer covering the adhesion layer;
A circuit board comprising:
(Appendix 10)
The organic compound having hydrogen bonding property has one or more of any two or more of C═O, C—O, O—H and N—H in the molecule, or C in the molecule. = Having two or more of any one of O, C—O, O—H, and N—H,
The circuit board according to appendix 9, wherein
(Appendix 11)
The organic compound having hydrogen bonding property is at least one compound selected from polyphenols, dextrins, monosaccharides, urea compounds and amino acid compounds.
The circuit board according to appendix 9 or 10, characterized in that.
(Appendix 12)
The silane coupling agent is an alkoxysilane having at least one selected from a vinyl group, amino group, ureido group, mercapto group, methacryloxy group, acryloxy group, isocyanate group, imidazole group and epoxy group as a functional group.
12. The circuit board according to any one of appendices 9 to 11, wherein

21, 51 Substrate 22 Underlying insulating film 23, 31 Metal adhesion layer 24, 32 Plating seed layer 25, 33 Photoresist film 25A, 33A Opening 26, 34, 60, 69 Cu wiring 27, 35, 56, 59, 61, 67, 70 Barrier layers 28, 36, 62 Adhesion layers 29, 37, 54, 58, 63, 65 Insulating layer 52 Element isolation film 53 Transistor 55 Protective layer 57 W plug 64, 66 Stopper film 68 Via contact

Claims (6)

An adhesion material that adheres the barrier layer covering the metal wiring and the insulating layer,
An organic compound having hydrogen bonding properties;
A silane coupling agent;
A contact material characterized by containing. The organic compound having hydrogen bonding property has one or more of any two or more of C═O, C—O, O—H and N—H in the molecule, or C in the molecule. = Having two or more of any one of O, C—O, O—H, and N—H,
The adhesive material according to claim 1. The organic compound having hydrogen bonding property is at least one compound selected from polyphenols, dextrins, monosaccharides, urea compounds and amino acid compounds.
The adhesive material according to claim 1 or 2, wherein The silane coupling agent is an alkoxysilane having at least one selected from a vinyl group, amino group, ureido group, mercapto group, methacryloxy group, acryloxy group, isocyanate group, imidazole group and epoxy group as a functional group.
The adhesion material according to any one of claims 1 to 3, wherein Forming metal wiring on the substrate;
Forming a barrier layer covering the metal wiring;
Covering the barrier layer and forming an adhesion layer containing a hydrogen bonding organic compound and a silane coupling agent;
Forming an insulating layer covering the adhesion layer;
A method of manufacturing a circuit board, comprising: A substrate,
Metal wiring formed on the substrate;
A barrier layer covering the metal wiring;
An adhesive layer covering the barrier layer and containing an organic compound having a hydrogen bonding property and a silane coupling agent;
An insulating layer covering the adhesion layer;
A circuit board comprising:

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