TWI808287B - laminated body - Google Patents

Abstract

The present invention is a laminate which provides a laminate capable of favorably peeling off a carrier substrate even when heat-treated at a temperature of 300° C. or higher. This laminated system has a carrier substrate, a laminated body of a peeling functional layer and a metal layer in sequence, wherein the peeling functional layer contains metal elements, and the surface of the peeling functional layer on the metal layer side is a fluoride-treated surface and/or a nitriding-treated surface, and for the peeling functional layer, the range in which the sum of the fluorine content and the nitrogen content is 1.0 atomic % or more exists throughout a thickness of 10 nm or more.

Description

laminated body

The present invention relates to a laminate having a carrier, a metal layer, etc. (for example, a copper foil with a carrier).

In recent years, multilayering of printed wiring boards has been widely carried out as miniaturization in order to increase the mounting density of printed wiring boards. Such multilayer printed wiring boards are used in many portable electronic devices for the purpose of weight reduction and miniaturization. In addition, for this multilayer printed wiring board, the thickness of the interlayer insulating layer is further reduced, and the weight reduction of a further layer of the wiring board is required.

As a technique satisfying such a request, a method of manufacturing a multilayer printed wiring board using a coalescing deposition method is employed. The coalescence deposition method refers to a multilayer method in which an insulating layer and a wiring layer are alternately laminated (stacked) without using a so-called core substrate. In the coalescence deposition method, it is proposed to use a laminate having a metal layer on a carrier that provides a peeling function so that the support and the multilayer printed wiring board can be easily peeled off. For example, Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2005-101137) discloses that it includes the use of copper foil with a carrier as a laminate, an insulating resin layer is attached to the carrier surface of the copper foil with the carrier as a support, and then on the side of the ultra-thin copper layer with the copper foil with the carrier, through processes such as photoresist processing, pattern electrolytic copper plating, and removal of the photoresist film to form the first wiring conductor. , A method of manufacturing a packaging substrate for mounting a semiconductor element by peeling off the carrier support substrate and removing the ultra-thin copper layer.

Thus, the carrier substrate is the component that is finally detached. Therefore, for example, specific releasability is required between the carrier substrate and the layer constituting the printed wiring board. Recently, as a peeling functional layer having a peeling function on the surface of a carrier substrate, a laminate including an adhesion layer containing a metal element, a peeling auxiliary layer, and a peeling layer made of carbon or the like in this order from the carrier substrate side has been proposed. For example, Patent Document 2 (International Publication No. 2017/149811) discloses: a carrier, an adhesive metal layer made of metal such as titanium, a peeling auxiliary layer made of copper, a peeling layer, and a carrier-attached copper foil with an ultra-thin copper layer. The peeling layer is preferably a carbon layer. In addition, this document also describes that in order to further reduce the thickness of the ultra-thin copper layer with the carrier copper foil, etc., the adhesion metal layer, the peeling auxiliary layer, the peeling layer and the ultra-thin copper layer are formed by sputtering. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Unexamined Patent Publication No. 2005-101137 [Patent Document 2] International Publication No. 2017/149811

However, there are cases where heat treatment is performed on a temperature condition of 200° C. or higher for forming a layer or the like constituting a printed wiring board on a laminate. However, for example, when using a laminate having the above-mentioned peeling functional layer, as shown in FIG. 4 , heat treatment at a temperature of 300° C. or higher has a problem that the carrier substrate cannot be peeled off satisfactorily.

This time, the inventors of the present invention obtained the insight that the carrier substrate can be detached well even when heat treatment is performed at a temperature of 300° C. or higher when the surface of the metal layer side of the peeling functional layer containing a metal element is subjected to fluoridation treatment and/or nitriding treatment so as to exist in a range containing fluorine and/or nitrogen in a specific ratio in a laminate having a carrier substrate, a peeling functional layer, and a metal layer in this order.

Accordingly, an object of the present invention is to provide a laminate that can be detached well from a carrier substrate even when heat treatment is performed at a temperature of 300° C. or higher.

According to one aspect of the present invention, there is provided a laminate comprising a carrier substrate, a peelable functional layer, and a metal layer in this order, wherein, The aforementioned peeling functional layer contains metal elements, The surface on the side of the metal layer of the peeling functional layer is a fluoride-treated surface and/or a nitriding-treated surface, and the peeling functional layer has a range in which the sum of the fluorine content and the nitrogen content is 1.0 atomic % or more throughout the laminate with a thickness of 10 nm or more.

laminated body

In FIG. 1, an example of the laminated body of this invention is shown schematically. As shown in FIG. 1 , the laminate 10 of the present invention is sequentially provided with: a carrier substrate 12 , a peelable functional layer 14 and a metal layer 16 . The peeling functional layer 14 is a layer containing metal elements, and is disposed on the carrier substrate 12 . The surface of the peeling functional layer 14 on the side of the metal layer 16 is a fluoride-treated surface and/or a nitriding-treated surface. In addition, the range in which the sum of the fluorine content and the nitrogen content of the exfoliation functional layer 14 is 1.0 atomic % or more extends over a thickness of 10 nm or more. Each peeling functional layer 14 and metal layer 16 may be a single layer composed of one layer, or a multilayer composed of two or more layers as shown in FIG. 1 may be used. In addition, the above-described various layers may be sequentially provided on both surfaces of the carrier substrate 12 in a vertically symmetrical manner. However, it is preferable to use the laminated body 10 of this invention for all uses, especially for printed wiring board manufacture.

As mentioned above, for forming the layer etc. which comprise a printed wiring board on a carrier base material, heat processing may be performed on temperature conditions of 200 degreeC or more, for example. For example, in the manufacturing process of the above-mentioned multilayer printed wiring board, a laminate used as a copper foil with a carrier may be subjected to hot press processing every time an insulating material is laminated, and the processing temperature of this hot pressing process depends on the hardening temperature of the laminated insulating material. However, in conventional laminates, when the heat treatment is performed at a temperature of 300° C. or higher, there has been a problem that the carrier substrate cannot be detached satisfactorily. Therefore, when using the conventional laminated body for the manufacture of a printed wiring board, etc., since it becomes a restriction|limiting heat-processing condition, processing design, for example, selection of a constituent material is also restricted. As an example, as shown in FIG. 3 , in a conventional laminate 110 sequentially provided with a carrier base material 112, an adhesive layer 114 containing a metal element, a peeling auxiliary layer 116 containing a metal element, a peeling layer 118 made of carbon, and a metal layer 120, the graph of peel strength after heating at various temperatures for 1 hour is shown in FIG. 4 . As shown in FIG. 4 , in the conventional laminate 110 , the peeling strength excessively increased by heating at 300° C. or higher, and the carrier substrate 112 could not be peeled off satisfactorily. Furthermore, it turned out that it became impossible to peel at 350 degreeC. Although the structure of the excessive increase in peel strength by heat treatment at 300°C or higher is not clear, it is estimated as follows. That is, as shown in FIG. 5 , when the laminate 110 having the above-mentioned structure is subjected to heat treatment at a high temperature of, for example, 300° C. or higher, a defect occurs in the peeling layer 118, and the metal element constituting these layers diffuses between the peeling auxiliary layer 116 and the metal layer 120 through the defect. As a result, it is considered that in the range between the peeling assistance layer 116 and the metal layer 120, for example, additional metal-metal bonding is promoted, and the peeling strength increases due to bonding.

On the other hand, according to the present invention, in the laminated body 10 provided with the carrier substrate 12, the peeling functional layer 14 and the metal layer 16 in this order, when the surface on the metal layer side of the peeling functional layer 14 containing metal elements is subjected to fluoridation treatment and/or nitriding treatment so that the range containing fluorine and/or nitrogen in a specific ratio exists, the carrier substrate 12 can be peeled off well when the heat treatment is performed at a temperature of 300° C. or higher. Although this structure is not clear, the following situations can be cited as one of the factors. However, in the following, as an example of the laminate 10 of the present invention, a laminate in which at least the metal layer 16 side of the peeling functional layer 14 is a copper layer, the surface of the peeling functional layer 14 on the metal layer 16 side is a fluorinated surface, and at least the peeling functional layer 14 side of the metal layer 16 is a titanium layer will be described. First, as shown in FIG. 2 , in the laminate 10 having the above configuration, the fluorine in the peeling functional layer 14 is considered to exist in the form of copper fluoride (CuF ₂ ) on the metal layer 16 side of the peeling functional layer 14 . Therefore, on the fluorinated surface, while fluorine and copper are bonded strongly through ion bonding, the bond between fluorine and titanium has a weak van der Waals force. Accordingly, when the carrier substrate 12 is peeled without heat treatment such as annealing, it is peeled from between the titanium layer of the metal layer 16 and the fluorinated surface of the peeling functional layer 14 . In addition, for example, in the case of high-temperature and long-term heat treatment of annealing at 400° C. for 2 hours, the fluorine system does not move to the titanium side, but may stay between the titanium layer and the copper layer. One of the reasons for this is that copper fluoride is more stable to heat than titanium fluoride (TiF ₄ ), which is a compound of fluorine and titanium. That is, the boiling point of copper fluoride is 950°C, which is quite high, compared to the sublimation temperature of titanium fluoride being 284°C. Therefore, it is considered that during the heat treatment, the bond between fluorine and copper is cut off, but the bond with titanium is not caused to sublimate. In addition, the second reason why fluorine stays between the titanium layer and the copper layer is that the binding force of fluorine is extremely strong. That is, since fluorine is strongly bonded to copper due to its high electronegative degree, it is considered that it exists as copper fluoride even after heat treatment. Then, as shown in FIG. 2, the copper fluoride existing on the surface of the metal layer 16 side of the peeling functional layer 14 becomes a barrier, and can suppress the diffusion of copper from the peeling functional layer 14 to the metal layer 16, and the diffusion of titanium from the metal layer 16 to the peeling functional layer 14. As a result, even when the heat treatment is performed at a temperature of 300° C. or higher, the carrier substrate 12 can be detached well from between the metal layer 16 and the release functional layer 14 as in the case of no heat treatment. Through this, for example, in the manufacturing process of a printed wiring board, it is possible to use a highly reliable insulating material that is difficult in conventional lamination systems and has a high curing temperature. As a result, it becomes possible to expand applications such as circuit formation of packages requiring relatively high reliability. However, the above description is based on the case of fluoridation treatment as an example, but in the case of nitriding treatment using nitrogen having chemical properties close to fluorine, it is considered that the effect can be obtained with the same structure.

From the above viewpoint, the surface of the laminate 10 on the metal layer 16 side of the peeling functional layer 14 is a fluoride-treated surface and/or a nitriding-treated surface, and is preferably a fluoridated-treated surface. Therefore, the peeling functional layer 14 contains fluorine and/or nitrogen to some extent. Specifically, the range in which the sum of the fluorine content and the nitrogen content of the exfoliation functional layer 14 is 1.0 atomic % or more (hereinafter referred to as "(F+N) range") is present throughout a thickness of 10 nm or more, preferably 20 nm or more, more preferably 30 nm or more, more preferably 40 nm or more, and particularly preferably 50 nm or more. In addition, the range in which the sum of the fluorine content and the nitrogen content of the exfoliation functional layer 14 is 2.0 atomic % or more is preferably distributed over a thickness of 5 nm or more, more preferably distributed over 10 nm or more, still more preferably distributed over 20 nm or more, still more preferably distributed over 30 nm or more, particularly preferably distributed over 40 nm or more, and most preferably distributed over a thickness of 50 nm or more. Ideally, the sum of the fluorine content and the nitrogen content on the fluorinated surface and/or the nitriding treated surface is 1.0 atomic % or more (more preferably 2.0 atomic % or more). Accordingly, it is preferable that the range of (F+N) exists on the side of the metal layer 16 of the peeling functional layer 14 . The upper limit of the sum of the fluorine content and the nitrogen content in the (F+N) range of the peeling functional layer 14 is typically 20 atomic %, more typically 10 atomic %, and still more typically 5 atomic %. The upper limit of the thickness of the (F+N) range of the peeling functional layer 14 is not particularly limited, and may be the same as the thickness of the peeling functional layer 14, but typically it is 80% of the thickness of the peeling functional layer 14, and more typically, it is 40% of the thickness of the peeling functional layer 14. When the surface on the side of the metal layer 16 of the peeling functional layer 14 is a fluoride-treated surface, it is preferable that the fluorine content alone falls within the above-mentioned range. That is, for the exfoliation functional layer 14, the range in which the fluorine content is 1.0 atomic % or more (hereinafter referred to as "F range") is preferably present throughout the thickness of 10 nm or more, and the ideal (or typical) form of the aforementioned (F+N) range is also directly applicable to the F range. The fluorinated surface can be ideally formed by reactive ion etching (RIE: Reactive ion etching) using a fluorine-containing reactive gas such as carbon tetrafluoride or sulfur hexafluoride. On the other hand, when the surface on the metal layer 16 side of the peeling functional layer is a nitrided surface, it is preferable that the nitrogen content alone falls within the above-mentioned range. That is to say, for the exfoliation functional layer 14, the range in which the nitrogen content is 1.0 atomic % or more (hereinafter referred to as "N range") is preferably present throughout the thickness of 10 nm or more, and the aforementioned ideal (or typical) form of the (F+N) range is also directly applicable to the N range. The nitrided surface can be ideally formed by reactive ion etching (RIE: Reactive ion etching) or reactive sputtering.

The (F+N) range, F range, and N range thickness ( _SiO2 conversion) of the exfoliation functional layer 14 can be specified by performing depth-direction elemental analysis of the laminate 10 using XPS as mentioned in the embodiments described later. However, in depth-direction elemental analysis using XPS, even when the same etching conditions are used, it is difficult to obtain the value of the thickness itself in the (F+N) range, F range, and N range because the etching rate is different according to the type of material. Therefore, the thickness in each range is the thickness calculated from the SiO ₂ equivalent calculated from the time required for etching using the etching rate calculated from the SiO ₂ film whose film thickness is known. By doing so, a quantifiable assessment can be made for the sole purpose of specifying the thickness.

The peelable functional layer 14 is a peelable layer of the peelable carrier substrate 12 and contains a metal element. It is preferable that the metal element contained in the peeling functional layer 14 has a negative standard electrode potential. The peeling functional layer 14 may be a single layer composed of one layer, or a multilayer composed of two or more layers. In the case where the peeling functional layer 14 is composed of two or more layers, the peeling functional layer 14 includes a first peeling functional layer 14a adjacent to the carrier substrate 12, and a second peeling functional layer 14b disposed on the opposite side of the carrier substrate 12 from the first peeling functional layer 14a. Another intervening layer may exist between the 1st peeling functional layer 14a and the 2nd peeling functional layer 14b. The overall thickness of the peeling functional layer 14 is preferably from 10 nm to 1000 nm, more preferably from 30 nm to 500 nm, still more preferably from 50 nm to 400 nm, particularly preferably from 100 nm to 300 nm. The thickness of the peeling functional layer 14 can be measured by analyzing the cross section of the layer with an energy dispersive X-ray spectrometer (TEM-EDX) of a transmission electron microscope.

The first peeling functional layer 14a provided as desired preferably includes a metal ^M1 having a negative standard electrode potential from the viewpoint of ensuring adhesion with the carrier substrate 12 . Examples of ideal ^M1 include: titanium, chromium, nickel, cobalt, aluminum, molybdenum, and combinations thereof (for example, alloys or intermetallic compounds), more preferably titanium, nickel, cobalt, aluminum, molybdenum, and combinations thereof, more preferably titanium, nickel, aluminum, molybdenum, and combinations thereof, particularly preferably titanium, nickel, molybdenum, and combinations thereof, most preferably titanium. The 1st peeling functional layer 14a may contain elements other than ^M1 in the range which does not impair the adhesiveness with the carrier base material 12. From the above point, the content of ^M1 in the first peeling functional layer 14a is preferably 50 atomic % or more, more preferably 60 atomic % or more, more preferably 70 atomic % or more, particularly preferably 80 atomic % or more, and most preferably 90 atomic % or more. On the other hand, the ^M1 content in the first peeling functional layer 14a may be 100 atomic % or less. The metal system constituting the first peeling functional layer 14a may contain unavoidable impurities due to raw material components or film-forming processes. In addition, although not particularly limited, the presence of oxygen mixed in due to exposure to the air after film formation of the first peeling functional layer 14a is allowed. The first peeling functional layer 14a is preferably a layer formed by physical vapor deposition (PVD), more preferably a layer formed by sputtering. The layer formed by the radio frequency magnetron sputtering method using the metal target as the 1st peeling functional layer 14a is especially preferable at the point that the uniformity of film thickness distribution can be improved. The thickness of the first peeling functional layer 14a is preferably not less than 5.0 nm and not more than 500 nm, more preferably not less than 10 nm and not more than 400 nm, more preferably not less than 30 nm and not more than 300 nm, still more preferably not less than 40 nm and not more than 200 nm, particularly preferably not less than 50 nm and not more than 100 nm.

The second peeling functional layer 14b provided as desired is from the point of controlling the peeling strength with the metal layer 16 to a desired value, preferably containing a metal ^M2 other than alkali metals and alkaline earth metals, and ^M2 is preferably a metal different from ^M1 . Examples of ideal ^M2 include: copper, silver, tin, zinc, titanium, aluminum, niobium, zirconium, tungsten, tantalum, molybdenum, and combinations thereof (for example, alloys or intermetallic compounds), more preferably copper, silver, tin, zinc, titanium, aluminum, molybdenum, and combinations thereof, more preferably copper, silver, titanium, aluminum, molybdenum, and combinations thereof, particularly preferably copper, silver, aluminum, and combinations thereof, most preferably copper. The second peeling functional layer 14b may contain elements other than M ² within a range that does not impair the peelability with the carrier substrate 12 . From the above point, the ^M2 content in the second peeling functional layer 14b is preferably 50 atomic % or more, more preferably 60 atomic % or more, more preferably 70 atomic % or more, particularly preferably 80 atomic % or more, and most preferably 90 atomic % or more. On the other hand, the content of M ² in the second peeling functional layer 14b may be 100 atomic % or less. The metal system constituting the second peeling functional layer 14b may contain unavoidable impurities due to raw material components or film-forming processes. In addition, although not particularly limited, the presence of oxygen mixed in due to exposure to air after film formation of the second peeling functional layer 14b is allowed. The second peeling functional layer 14b is preferably a layer formed by physical vapor deposition (PVD), more preferably a layer formed by sputtering. The layer formed by the radio frequency magnetron sputtering method using the metal target as the second peeling functional layer 14b is particularly preferable in that the uniformity of the film thickness distribution can be improved. The thickness of the second peeling functional layer 14b is preferably not less than 5.0nm and not more than 990nm, more preferably not less than 20nm and not more than 800nm, more preferably not less than 50nm and not more than 500nm, still more preferably not less than 100nm and not more than 300nm, particularly preferably not less than 150nm and not more than 250nm.

As a combination of ^M1 and ^M2 , ^M1 is titanium, nickel, aluminum or molybdenum, and ^M2 is copper, silver, titanium, aluminum or molybdenum. More desirably ^M1 is titanium, nickel or molybdenum, and ^M2 is copper, silver, or aluminum. It is especially desirable that M ¹ is titanium and M ² is copper. By doing so, it becomes easier to impart the aforementioned desired peel strength to the laminate 10 .

According to expectations, the intervening layer is an alloy of the above-mentioned ^M1 and ^M2 . Accordingly, the aforementioned ideal combination of ^M1 and ^M2 is also directly applicable to the ideal combination of ^M1 and ^M2 forming the intervening layer. The thickness of the intervening layer is preferably from 10 nm to 1000 nm, preferably from 30 nm to 500 nm, more preferably from 50 nm to 400 nm, still more preferably from 100 nm to 300 nm, particularly preferably from 150 nm to 250 nm.

On the other hand, when the peeling functional layer 14 is composed of one layer, the above-mentioned first peeling functional layer 14a may be directly used as an intermediate layer, and the first peeling functional layer 14a and the second peeling functional layer 14b may be replaced by a single intermediate alloy layer. The intermediate alloy layer can be an alloy of ^M1 and ^M2 . Accordingly, the aforementioned ideal combination of ^M1 and ^M2 is also directly applicable to the ideal combination of ^M1 and ^M2 constituting the intermediate alloy layer. The thickness of the intermediate alloy layer is preferably based on the thickness of the entire peelable functional layer 14 described above.

The material of the carrier substrate 12 can be any one of glass, ceramics, silicon, resin, and metal, and can be appropriately selected according to the application of the laminated body 10 . Ideally, the carrier substrate 12 is a glass substrate, a ceramic substrate or a silicon wafer. In addition, the form of the carrier substrate 12 may be any of sheet, film, plate and foil. In addition, the carrier base material 12 may be formed by laminating such sheets, films, plates, foils, and the like. For example, the carrier substrate 12 may be configured to function as a rigid support such as a glass plate, a ceramic plate, a silicon wafer, or a metal plate, or may be in a non-rigid form such as a metal foil or a resin film. Preferable examples of the metal of the carrier substrate 12 include copper, titanium, nickel, stainless steel, aluminum, and the like. Ideal examples of ceramics include alumina, zirconium, silicon nitride, aluminum nitride, and various other fine ceramics. Preferable examples of the resin include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyamide, polyimide, nylon, liquid crystal polymer, polyether ether ketone (PEEK (registered trademark)), polyamide imide, polyether sulfide, polyphenylene sulfide, polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), and the like. Among them, a material having a coefficient of thermal expansion (CTE) of less than 25 ppm/K, typically not less than 1.0 ppm/K and not more than 23 ppm/K is preferable from the viewpoint of preventing bending of the polymeric support accompanying heating when mounting electronic components. Examples of such materials include, in particular, low thermal expansion resins such as polyimide and liquid crystal polymer, glass, silicon, and ceramics. In addition, the Vickers hardness of the carrier substrate 12 is, for example, preferably 100 HV or higher, and more preferably 150 HV or higher, from the viewpoint of handling and ensuring flatness during wafer mounting. On the other hand, the Vickers hardness of the carrier substrate 12 can be, for example, 2500 HV or less. As a material satisfying these characteristics, the carrier substrate 12 is preferably made of a resin film, glass, silicon or ceramics, among which glass, silicon or ceramics is preferable, especially glass. As the carrier base material 12 which consists of glass, a glass flake is mentioned, for example. When glass is used as the carrier substrate 12, it is lightweight, has a low coefficient of thermal expansion, has high insulation properties, is rigid, and has a flat surface, so that the surface of the metal layer 16 can be extremely smooth. Moreover, when the carrier base material 12 is glass, since the laminated body 10 is used as copper foil with a carrier for the manufacture of a printed wiring board, there are various advantages. For example, after the wiring layer on the surface of the polymeric support is formed, the copper plating is superior in image inspection, the surface flatness when electronic components are mounted, the so-called coplanarity, the chemical resistance in the electroless copper plating of the printed wiring board manufacturing process or in various plating processes, and the chemical separation method can be used in the separation of build-up laminates. Preferable examples of the glass constituting the carrier substrate 12 include: quartz glass, borosilicate glass, alkali-free glass, soda-lime glass, aluminosilicate glass, and combinations thereof, and particularly preferable examples include: alkali-free glass. Alkali-free glass refers to glass that contains alkaline earth metal oxides such as silicon dioxide, aluminum oxide, boron oxide, and calcium oxide or barium oxide as the main component, and contains boric acid, but substantially does not contain alkali metals. This alkali-free glass is in a wide temperature range from 0°C to 350°C, and its thermal expansion coefficient is low and stable, for example, in the range of 3ppm/K to 5ppm/K, and it has the advantage of minimizing the bending of the glass when mounting semiconductor chips as electronic components. The thickness of the carrier substrate 12 is, for example, preferably from 100 μm to 2000 μm, more preferably from 300 μm to 1800 μm, and more preferably from 400 μm to 1100 μm. When the thickness is within such a range, it is possible to reduce the thickness of the printed wiring board and reduce the bending that occurs when electronic components are mounted while ensuring appropriate strength that does not hinder handling.

The arithmetic mean roughness Ra of the surface of the carrier substrate 12 on the side of the peeling functional layer 14 is preferably 0.1 nm to 70 nm, more preferably 0.5 nm to 60 nm, more preferably 1.0 nm to 50 nm, particularly preferably 1.5 nm to 40 nm, and most preferably 2.0 nm to 30 nm. By reducing the above-mentioned arithmetic average roughness, a good arithmetic average roughness Ra can be achieved on the surface of the metal layer 16 opposite to the peeling functional layer 14 , that is, the outer surface of the metal layer 16 . Thereby, in the printed wiring board manufactured using the laminated body 10, for example, it can be made into the structure suitable for forming the wiring pattern whose height was miniaturized. Here, the highly miniaturized wiring pattern refers to, for example, a wiring pattern designed within a range of 2 μm/2 μm or more and 12 μm/12 μm or less in line/space (L/S) of 13 μm or less/13 μm or less. However, the arithmetic mean roughness Ra mentioned above can be measured by the method based on JIS B 0601-2001.

The metal layer 16 is a layer made of metal. The metal layer 16 may be composed of one layer, or may be composed of two or more layers. In the case where the metal layer 16 is composed of two or more layers, the metal layer 16 may be formed by sequentially stacking metal layers from the first metal layer 16a to the m-th metal layer (m is an integer of 2 or more) on the side opposite to the carrier substrate 12 of the peeling functional layer 14. The overall thickness of the metal layer 16 is preferably from 100 nm to 2000 nm, preferably from 150 nm to 1500 nm, more preferably from 200 nm to 1000 nm, still more preferably from 300 nm to 800 nm, particularly preferably from 350 nm to 500 nm. The thickness of the metal layer 16 can be measured by analyzing the layer profile with an energy dispersive X-ray spectrometer (TEM-EDX) of a transmission electron microscope. Hereinafter, an example in which the metal layer 16 is constituted by two layers of the first metal layer 16a and the second metal layer 16b will be described.

The first metal layer 16 a is not particularly limited as long as it imparts desired functions such as an etching stop function and a reflection prevention function to the laminate 10 . Desirable examples of the metal constituting the first metal layer 16a include: titanium, aluminum, niobium, zirconium, chromium, tungsten, tantalum, cobalt, silver, nickel, molybdenum, and combinations thereof, more preferably titanium, zirconium, aluminum, chromium, tungsten, nickel, molybdenum, and combinations thereof, more preferably titanium, aluminum, chromium, nickel, molybdenum, and combinations thereof, particularly preferably titanium, molybdenum, and combinations thereof. These elements have the property of not dissolving in rapid etching liquid (for example, copper rapid etching liquid), and as a result, they can exhibit superior chemical resistance to rapid etching liquid. Accordingly, the first metal layer 16a is a layer that is easily etched by the rapid etchant as the second metal layer 16b described later, and therefore can function as an etching stopper layer. In addition, since the above-mentioned metal system constituting the first metal layer 16a also has the function of preventing light reflection, the first metal layer 16a can also function as an antireflection layer for improving visibility in image inspection (for example, automatic image inspection (AOI)). The first metal layer 16a can also be a pure metal or an alloy. The metal system constituting the first metal layer 16a may contain unavoidable impurities due to raw material components, film formation process, and the like. In addition, the upper limit of the content rate of the said metal is not specifically limited, It may be 100 atomic%. The first metal layer 16a is preferably a layer formed by physical vapor deposition (PVD), more preferably a layer formed by sputtering. The thickness of the first metal layer 16a is preferably not less than 1 nm and not more than 500 nm, more preferably not less than 10 nm and not more than 400 nm, more preferably not less than 30 nm and not more than 300 nm, particularly preferably not less than 50 nm and not more than 200 nm.

Desirable examples of the metal constituting the second metal layer 16b include transition elements of Group 4, Group 5, Group 6, Group 9, Group 10, and Group 11, aluminum, and combinations thereof (for example, alloys or intermetallic compounds), more preferably copper, gold, titanium, aluminum, niobium, zirconium, chromium, tungsten, tantalum, cobalt, silver, nickel, molybdenum, and combinations thereof, and more preferably copper, gold, titanium, aluminum, niobium, zirconium, cobalt, silver, nickel, molybdenum. And these combinations, more preferably copper, gold, titanium, aluminum, silver, molybdenum and these combinations, particularly preferably copper, gold, titanium, molybdenum and these combinations, most preferably copper. The second metal layer 16b can be manufactured by any method, for example, a metal foil formed by a wet film-forming method such as an electroless metal plating method and an electrolytic metal plating method, a physical vapor deposition (PVD) method such as sputtering and vacuum evaporation, a chemical vapor phase film formation, or a combination thereof. In particular, the second metal layer 16b is preferably a metal layer formed by physical vapor deposition (PVD) methods such as sputtering or vacuum evaporation, and is most preferably a metal layer produced by sputtering from the viewpoint of being easy to respond to micro-pitching through extremely thinning. In addition, the second metal layer 16b is preferably a metal layer without roughening. On the other hand, in the case of using the laminate 10 in the manufacture of a printed wiring board, the second metal layer 16b may be the one that causes secondary roughening through preparatory roughening, soft etching treatment, cleaning treatment, or oxidation-reduction treatment as long as it does not cause obstacles to the formation of wiring patterns during the production of printed wiring boards. From the viewpoint of corresponding to the micro pitch as described above, the thickness of the second metal layer 16b is preferably from 10 nm to 1000 nm, more preferably from 20 nm to 900 nm, more preferably from 30 nm to 700 nm, still more preferably from 50 nm to 600 nm, particularly preferably from 70 nm to 500 nm, and most preferably from 100 nm to 400 nm. A metal layer having a thickness within such a range produced by sputtering is ideal in terms of in-plane uniformity of film formation thickness, or productivity in sheet or roll form.

The surface of the second metal layer 16b opposite to the first metal layer 16a (the outer surface of the metal layer 16) is preferably 1.0 nm to 100 nm, more preferably 2.0 nm to 40 nm, more preferably 3.0 nm to 35 nm, particularly preferably 4.0 nm to 30 nm, and most preferably 5.0 nm to 15 nm. . In this way, the smaller the arithmetic mean thickness is, for example, in a printed wiring board manufactured using the laminated body 10, it becomes a configuration suitable for forming a highly miniaturized wiring pattern. Here, the highly miniaturized wiring pattern refers to, for example, a wiring pattern designed within a range of 2 μm/2 μm or more and 12 μm/12 μm or less in line/space (L/S) of 13 μm or less/13 μm or less.

When the metal layer 16 is composed of one layer, it is preferable to directly use the above-mentioned second metal layer 16 b as the metal layer 16 . On the other hand, when the metal layer 16 is composed of n layers (n is an integer greater than or equal to 3), it is preferable to use the first metal layer 16a to the (n-1)th metal layer of the metal layer 16 as the composition of the above-mentioned first metal layer 16a, and to use the outermost layer of the metal layer 16, that is, the n-th metal layer, as the composition of the above-mentioned second metal layer 16b.

When the laminate 10 is provided with a heat history of 300° C. or higher, it is preferable that the peel strength between the peelable functional layer 14 and the metal layer 16 is within a desired range. Specifically, the peel strength is preferably 1.0 gf/cm to 50 gf/cm, more preferably 2.0 gf/cm to 30 gf/cm, and more preferably 3.0 gf/cm to 20 gf/cm. More specifically, when a thermal history is given at 400° C. for 2 hours to the laminate 10 , it is preferable that the peeling strength between the peeling functional layer 14 and the metal layer 16 falls within the above-mentioned range. When the via peeling strength is within the above range, it is possible to perform good peeling in the peeling process while maintaining the specific peeling strength. This peel strength can be measured based on JIS Z 0237-2009.

Manufacturing method of laminated body The laminate 10 according to the present invention is prepared by preparing a carrier substrate 12 , and can be manufactured by forming a peelable functional layer 14 and a metal layer 16 on the carrier substrate 12 . The formation of the peeling functional layer 14 is ideally processed by processing the side opposite to the carrier substrate 12 of the peeling functional layer 14 by reactive ion etching after the layer constituting the peeling functional layer 14 is formed into a film on the carrier substrate 12 by a physical vapor deposition (PVD) method. On the other hand, the formation of the metal layer 16 is preferably performed by a physical vapor deposition (PVD) method from the viewpoint of being easy to respond to the micro-pitch through ultra-thinning. Examples of the physical vapor deposition (PVD) method include a sputtering method, a vacuum evaporation method, and an ion plating method. Among them, it is preferable to use the sputtering method from the point that the film thickness can be controlled in a wide range from 0.05nm to 5000nm, and from the point that the uniformity of film thickness can be ensured over a wide width or area. The film formation by the physical vapor deposition (PVD) method is not particularly limited as long as it is performed under known conditions using a known vapor phase film forming apparatus. For example, in the case of using the sputtering method, various known methods such as the magnetron sputtering method, the bipolar sputtering method, and the facing target sputtering method can be mentioned as the sputtering method. Among them, the magnetron sputtering method is ideal because the film forming speed is fast and the productivity is high. The sputtering method can also be performed by any power source of DC (direct current) and RF (high frequency). In addition, in the sputtering method, a plate-type target whose target shape is widely known can be used. Among them, from the viewpoint of target use efficiency, it is preferable to use a cylindrical target. Hereinafter, the film formation by the physical vapor deposition (PVD) method of the peeling functional layer 14, the formation of the fluorinated surface by reactive ion etching on the side opposite to the carrier substrate 12 of the peeling functional layer 14, and the film formation by the physical vapor deposition (PVD) method of the metal layer 16 will be described. However, in the following description, the laminate 10 is constituted as the peeling functional layer 14 by the first peeling functional layer 14a and the second peeling functional layer 14b, and the metal layer 16 is constituted by the first metal layer 16a and the second metal layer 16b.

The physical vapor deposition (PVD) method (ideal sputtering method) of the first peeling functional layer 14a is formed using a target made of the above-mentioned metal ^M1 in a non-oxidizing environment. It is ideal that the uniformity of the film thickness distribution can be improved by using the radio frequency magnetron sputtering method. The purity of the target is preferably above 99.9%. Examples of the gas system used for sputtering include inert gases such as argon. The flow rate of argon gas can be properly determined according to the size of the sputtering chamber and the film forming conditions. In addition, from the standpoint of suppressing abnormal discharge and poor plasma irradiation and continuous film formation, the pressure during film formation is preferably 0.1 Pa or more and 20 Pa or less. This pressure range is set according to the structure and capacity of the device, the exhaust capacity of the vacuum pump, the rated capacity of the film-forming power supply, etc., and the film-forming power and the flow rate of argon gas can be adjusted. In addition, the sputtering power takes into account the film thickness uniformity of film formation, productivity, etc., and it can be 0.05W/cm ² or more and 10.0W/cm ² or less per unit area of the target.

The film formation via the physical vapor deposition (PVD) method (ideal sputtering method) of the second peeling functional layer 14b uses a target composed of the above-mentioned metal ^M2 in a non-oxidizing environment, and it is ideal that the radio frequency magnetron sputtering method can improve the uniformity of the film thickness distribution. The purity of the target is preferably above 99.9%. As a gas system used for sputtering, the inert gas, such as argon gas, is mentioned, for example. The flow rate of argon gas can be properly determined according to the size of the sputtering chamber and the film forming conditions. In addition, from the standpoint of suppressing abnormal discharge and poor plasma irradiation and continuous film formation, the pressure during film formation is preferably 0.1 Pa or more and 20 Pa or less. This pressure range is set according to the structure and capacity of the device, the exhaust capacity of the vacuum pump, the rated capacity of the film-forming power supply, etc., and the film-forming power and the flow rate of argon gas can be adjusted. In addition, the sputtering power takes into account the film thickness uniformity of film formation, productivity, etc., and it can be 0.05W/cm ² or more and 10.0W/cm ² or less per unit area of the target.

The reactive ion etching of the surface on the side of the metal layer 16 side of the laminated peeling functional layer 14, that is, the surface of the second peeling functional layer 14b on the opposite side of the first peeling functional layer 14a is preferably carried out using a reactive gas containing fluorine such as carbon tetrafluoride or sulfur hexafluoride, and it is more preferable to use a reactive gas containing carbon tetrafluoride. The flow rate of the reaction gas is preferably not less than 10 sccm and not more than 300 sccm. From the viewpoint of cleaning impurities adhering to the surface of the peeling functional layer 14 and promoting fluorination, the reaction gas system may contain oxygen. At this time, the flow rate of oxygen is preferably not less than 1.0 sccm and not more than 10 sccm. From the point of containing sufficient amount of fluorine on the metal layer 16 side surface of the laminated release functional layer 14, the reaction time is preferably 0.5 minutes or more and 10 minutes or less. The treatment pressure is preferably above 1Pa and below 30Pa. In addition, the RF output system can be 50W or more and 1000W or less.

The film formation via the physical vapor deposition (PVD) method (ideal sputtering method) of the first metal layer 16a uses a target made of at least one metal selected from the group consisting of titanium, aluminum, niobium, zirconium, chromium, tungsten, tantalum, cobalt, silver, nickel and molybdenum, and it is preferably performed by radio frequency magnetron sputtering. The purity of the target is preferably above 99.9%. In particular, it is preferable that the film formation via the magnetron sputtering method of the first metal layer 16a be performed under an inert gas atmosphere such as argon. The pressure during film formation is preferably from 0.1 Pa to 20 Pa, more preferably from 0.2 Pa to 15 Pa, and more preferably from 0.3 Pa to 10 Pa. However, the control of the above-mentioned pressure range can be carried out by adjusting the film-forming power and the flow rate of argon gas according to the structure and capacity of the device, the exhaust capacity of the vacuum pump, the rated capacity of the film-forming power supply, etc. The flow rate of argon gas can be properly determined according to the size of the sputtering chamber and the film forming conditions. In addition, the sputtering power is considered to be uniform in film thickness, productivity, etc., and it can be 1.0W/cm2 ^or more and 15.0W/cm2 ^or less per unit area of the target. In addition, it is desirable to keep the carrier temperature constant during film formation because it is easy to obtain a film with stable film characteristics such as film resistance and crystal size. The carrier temperature during film formation is preferably 25°C to 300°C, more preferably 40°C to 200°C, more preferably 50°C to 150°C.

The film formation via the physical vapor deposition (PVD) method (ideal sputtering method) of the second metal layer 16b, for example, uses a target composed of at least one metal selected from the group consisting of transition elements from Group 4, Group 5, Group 6, Group 9, Group 10, and Group 11, and aluminum, preferably in an inert environment such as argon. Metal targets such as copper targets are preferably made of metals such as copper, but may contain unavoidable impurities. The purity of the metal target is preferably 99.9% or higher, more preferably 99.99% or higher, and even more preferably 99.999% or higher. In order to avoid temperature rise during vapor phase film formation of the second metal layer 16b, a platform cooling mechanism may be provided during sputtering. In addition, from the viewpoint of suppressing the occurrence of malfunctions such as abnormal discharge and plasma irradiation failure, and stable film formation, the pressure during film formation is preferably 0.1 Pa or more and 2.0 Pa or less. This pressure range is set according to the structure and capacity of the device, the exhaust capacity of the vacuum pump, the rated capacity of the film-forming power supply, etc., and the film-forming power and the flow rate of argon gas can be adjusted. In addition, the sputtering power takes into account the film thickness uniformity of film formation, productivity, etc., and it can be 0.05W/cm ² or more and 10.0W/cm ² or less per unit area of the target. [Example]

The present invention will be described more specifically through the following examples.

example 1 As shown in FIG. 1 , on the carrier substrate 12, the peeling functional layer 14 (the first peeling functional layer 14a and the second peeling functional layer 14b) and the metal layer 16 (the first metal layer 16a and the second metal layer 16b) are sequentially formed into films to produce a laminate 10. The specific steps are as follows.

(1) Preparation of carrier As the carrier substrate 12, a silicon wafer (manufactured by Wakatec Co., Ltd.) with a thickness of 100 mm was prepared.

(2) Formation of the first peeling functional layer 14a On the carrier substrate 12, as the first peeling functional layer 14a, a titanium layer with a thickness of 100 nm was formed by sputtering. This sputtering was performed using the following equipment under the following conditions. - Device: Leaf type RF magnetron sputtering device (manufactured by Canon Tokki Co., Ltd., MLS464) - Target: 8-inch (203.2mm) diameter titanium target (purity: 99.999%) - Reached vacuum: less than 1×10 ^-4 Pa - Carrier gas: argon (flow rate: 100sccm) - Sputtering pressure: 0.35Pa - Sputtering power: 1000W (3.1W/cm ² ) ‐ Film forming temperature: 40°C

(3) Formation of the second peeling functional layer 14b on the surface of the first peeling functional layer 14a, as the second peeling functional layer 14b, a copper layer with a thickness of 100nm was formed by sputtering. This sputtering was performed using the following equipment under the following conditions. - Device: leaf type DC sputtering device (manufactured by Canon Tokki Co., Ltd., MLS464) - Target: copper target with a diameter of 8 inches (203.2mm) (purity: 99.98%) - Reached vacuum: less than 1×10 ^-4 Pa - Gas: Argon (flow rate: 100sccm) - Sputtering pressure: 0.35Pa - Sputtering power: 1000W (6.2W/cm ² ) - Cheng Film temperature: 40°C

(4) Formation of fluorinated surface On the surface of the second peeling functional layer 14b, a fluorinated surface is formed by reactive ion etching. This reactive ion etching was performed using the following equipment under the following conditions. - Device: Reactive ion etching device (manufactured by SAMCO Co., Ltd., 10NR) - Reactive gas: carbon tetrafluoride gas (flow: 50sccm) and oxygen (flow: 5sccm) - Handling pressure: 5Pa - RF output: 300W - Response time: 3 minutes

(5) Formation of the first metal layer 16a On the fluorinated surface of the second peeling functional layer 14b, as the first metal layer 16a, a titanium layer with a thickness of 100nm was formed by sputtering. This sputtering was performed using the following equipment under the following conditions. - Device: Leaf type RF magnetron sputtering device (manufactured by Canon Tokki Co., Ltd., MLS464) - Target: 8-inch (203.2mm) diameter titanium target (purity: 99.999%) - Reached vacuum: less than 1×10 ^-4 Pa - Carrier gas: argon (flow rate: 100sccm) - Sputtering pressure: 0.35Pa - Sputtering power: 1000W (3.1W/cm ² ) ‐ Film forming temperature: 40°C

(6) Formation of the second metal layer 16b On the surface of the first metal layer 16a, a copper layer having a thickness of 300 nm was formed as the second metal layer 16b by sputtering. This sputtering was performed using the following equipment under the following conditions. - Device: leaf type DC sputtering device (manufactured by Canon Tokki Co., Ltd., MLS464) - Target: copper target with a diameter of 8 inches (203.2mm) (purity: 99.98%) - Reached vacuum: less than 1×10 ^-4 Pa - Carrier gas: argon (flow rate: 100sccm) - Sputtering pressure: 0.35Pa - Sputtering power: 1000W (3.1W/cm ² ) - Film forming temperature: 40°C

Example 2 A laminate was produced in the same manner as in Example 1, except that reactive ion etching for forming the fluorinated surface was performed under the following conditions.

(Reactive ion etching processing conditions) - Reactive gas: carbon tetrafluoride (flow rate: 50sccm) - Handling pressure: 5Pa - RF output: 300W - Response time: 5 minutes

Example 3 (comparison) A laminate was produced in the same manner as in Example 1, except that the fluorinated surface was not formed, that is, reactive ion etching was not performed.

Evaluate Various evaluations were performed on the laminates of Examples 1 to 3 as shown below.

＜Assessment 1: Quantitative analysis of peeled functional layer＞ In Examples 1 and 3, elemental analysis in the depth direction of the produced laminate 10 was performed by XPS on the basis of the following conditions and analysis conditions. This analysis was carried out while the laminate 10 was penetrated by Ar ion etching from the surface of the second metal layer 16b toward the depth direction under the following conditions.

(Ar ion etching conditions) - Accelerating voltage: 500V - Etching area: 2mm×2mm - Etching rate: 1.4nm/min in terms of _SiO2

(measurement conditions) - Device: X-ray photoelectron spectroscopy device (manufactured by ULVAC･PHI Co., Ltd., Quantum2000) - Excitation X-ray: Monochromatic Al-Kα line (1486.6eV) - Output: 100W - Acceleration voltage: 15kV - X-ray irradiation aperture: diameter 100μm - Measuring area: diameter 100μm×1mm - Channel energy: 23.5eV - Energy spacing: 0.1eV - Neutralizing gun: Yes - Determination of elements and orbits: (number of sweeps: Ratio: number of Cycles) O 1s:(5:6:1) Cu 2p3:(2:6:1) C 1s:(3:6:1) Ti 2p:(2:6:1) Si 2p:(1:6:1) F 1s:(15:6:1)

(analysis condition) XPS data analysis was performed using data analysis software (manufactured by ULVAC･PHI Co., Ltd., "multi-pack Ver9.4.0.7"). The leveling system is performed at 9 o'clock, and the background mode system uses Shirley. However, the background range of each element calculated quantitatively is as follows. -O 1s:528.0~540.0eV - Cu 2p3:927.0~939.0eV - C 1s:280.0~292.0eV ‐Ti 2p:451.2~464.5eV - Si 2p: Set as 0 because the peak value is below the lower limit of detection. - F 1s:686.0~686.5eV

The results of the fluorine quantitative values in the depth direction of the laminate 10 are shown in FIG. 6 . In FIG. 6 , the fluorine quantitative value of Example 1 is shown by a solid line, and the fluorine quantitative value of Example 3 is shown by a broken line. In addition, the thickness in the range where the sum of the fluorine content and nitrogen content of the peeling functional layer 14 is 1.0 atomic % or more, and the thickness in the range where the sum of the fluorine content and nitrogen content is 2.0 atomic % or more are shown in Table 1. However, in Example 2, although the elemental analysis in the depth direction of the laminate 10 was not carried out, but from the case where the reactive ion etching was performed using the carbon tetrafluoride gas at the same flow rate as in Example 1 and the reaction time was longer than that in Example 1, and the fluorinated surface was formed, the thicknesses in the above ranges were considered to be equal to or greater than those in Example 1.

＜Evaluation 2: Detachability of the metal layer＞ The peel strength after performing the annealing treatment as the thermal history of the laminate 10 was measured. Specifically, on the side of the second metal layer 16 b of the laminate 10 , panel electrolytic copper plating with a thickness of 18 μm was applied to form a copper plating layer, and a sample for peelability evaluation was prepared. The sample for peelability evaluation was heated at 400° C. for 2 hours in a nitrogen atmosphere. About the sample for peelability evaluation after heating, the said electrolytic copper plating layer integrated with the 2nd metal layer 16b was peeled based on JIS Z 0237-2009, and it was judged whether peeling was possible. The results are shown in Table 1.

12: Carrier substrate 14: Peel off the functional layer 14a: The first peeling functional layer 14b: The second peeling functional layer 16: metal layer 16a: The first metal layer 16b: The second metal layer 110: laminated body 114: adhesion layer 116:Peel off subsidy layer 118: peeling layer 120: metal layer

[ Fig. 1 ] is a schematic cross-sectional view showing an example of the laminate of the present invention. [FIG. 2] An enlarged view of the area between the peeled functional layer and the metal layer of the laminate in FIG. 1. [FIG. [ Fig. 3 ] is a schematic cross-sectional view showing an example of a conventional laminated body. [ Fig. 4 ] is a graph showing the peel strength of the conventional laminate shown in Fig. 3 after heating at various temperatures for 1 hour. [ Fig. 5 ] is an enlarged view of the area between the delamination assisting layer and the metal layer in the conventional laminate shown in Fig. 3 . [FIG. 6] It is a figure which shows the result of the quantitative value of the fluorine by XPS of the laminated body produced in Example 1 and Example 3.

10: laminated body

12: Carrier substrate

14: Peel off the functional layer

14a: The first peeling functional layer

14b: The second peeling functional layer

16: metal layer

16a: The first metal layer

16b: The second metal layer

Claims (5)

A laminate, which is sequentially provided with a carrier substrate, a peeling functional layer and a metal layer, wherein The aforementioned peeling functional layer contains metal elements; The surface of the metal layer side of the peeling functional layer is a fluoride-treated surface and/or a nitriding-treated surface, and in the peeling functional layer, the range in which the sum of the fluorine content and the nitrogen content is 1.0 atomic % or more exists throughout the thickness of 10 nm or more. The laminate according to claim 1, wherein in the exfoliation functional layer, the range in which the sum of the fluorine content and the nitrogen content is 2.0 atomic % or more exists over a thickness of 5 nm or more. The laminate according to claim 1 or claim 2, wherein the thickness of the peeling functional layer is not less than 10 nm and not more than 1000 nm. The laminate according to claim 1 or claim 2, wherein the aforementioned metal element contained in the aforementioned peeling functional layer has a negative standard electrode potential. The laminate according to claim 1 or claim 2, wherein the aforementioned carrier substrate is a glass substrate, a ceramic substrate or a silicon wafer.

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