TWI305585B - A wiring substrate and method using the same - Google Patents

Description

1305585

93042TW IX. Description of the Invention: [Technical Field of the Invention] The present invention relates mainly to a wiring board used in a display panel and a method of manufacturing the same. [Prior Art] A liquid crystal display panel is formed by sealing a liquid crystal between a wiring board and a color light-emitting board which are aligned. Recently, an active matrix liquid crystal display panel in which a gate line and a signal line intersect each other on the wiring substrate are wired in parallel. In addition, the two are also equipped with a film

Thin Film Transistors (hereinafter referred to as TFT). At present, the gate line and the signal line of the wiring substrate use a metal whose main component is aluminum A1 or aluminum A1 alloy, such as Xiang Mo/Ming alloy Alalloy or pure aluminum A1, and then use phosphoric acid (Phosph〇ric)/Acetic acid (Acetic) / Nitric This series of engraved liquids (hereinafter referred to as PAN series) is subjected to an etching step to form a trapezoidal shape in cross section. Recently, with the high quality of the panel and the large screen, the wiring impedance and the parasitic capacitance have increased greatly, and the problem of delay in wiring has been highlighted. However, in the current situation, if the aperture ratio is not affected, only the wiring film thickness is increased 'but this is the case, the chemical vapor deposition cv 〇 insulating film is disposed thereon, • if the lining is not increased, Absolute and miscellaneous (4) places do not care about the required insulation, and it is easy to cause poor step coverage, which leads to a decrease in manufacturing yield. • In the future, it may be possible to use a lower-impedance material such as copper Cu as a wiring material to solve this problem. However, the use of copper Cu as a wiring material has the following problems to be overcome: (1) a method for effectively suppressing copper Cu 'diffusion; (2) improving copper Cu • Adhesion between plates; (3) A method that requires trapezoidal patterning. The above-mentioned (1) suppression method is necessary to suppress the internal diffusion of copper Cu in the amorphous silicon of the preparation TFT, resulting in the inferiority of the semi-conducting ship, and the above (2) Cu and substrate-prone problems, mainly the glass substrate and the rotation Heart metal (_ job) Cu's adhesion is not good, so at 1305585

93042TW When the step of preparing Cu is made, it is easy to cause Cu to fall off the substrate. In addition, unlike the gold-stained oysters, after the metal is finished, the speed of the butterfly is faster than that of the Mo. Therefore, after the aging, the surface of the Cu roof (cover) is opened, and the upper Mo layer is easy to cut. In a similar factory, when the covered wiring is applied to the subsequent insulating layer, the covering production is reduced: the product is defective. Therefore, it is necessary to solve the problem. It is difficult to form hundreds of people in such a way that the diffusion of the CU in the Cu Cu 1 method (4) A film with a degree of % and a smooth surface. Therefore, how to integrate with the liquid crystal display manufacturing industry becomes a problem.

The three-layer construction of IsTa/copper Cu/boring is a consideration. The upper group

Ta is used as a contact metal (c〇ntactmetai) as a diffusion suppressing film for copper. The lower layer is used as a contact with glass. However, the Ta#Cu_ engraving method will become dry _-secret-dry_multi-stage _, and there are still some problems to be solved in terms of production cost and wiring shape. [Patent Document 1] Patent Publication 2 〇〇3 - 3 5 3 2 2 2 ([23] to % [3 1]) [Invention] [The present invention provides a close-contact, low-impedance value with a substrate A high-quality and high-quality wiring substrate that sufficiently prevents Cu from diffusing. A wiring substrate comprising: a substrate; and a copper wiring layer disposed on the substrate, wherein the copper wiring layer is copper or copper as a main component; a diffusion suppression layer, the diffusion suppression layer is disposed on The upper portion and the side surface of the copper wiring layer, and the diffusion suppressing layer is a nitrogen-containing metal. An adhesive adhesion layer may be disposed on the lower portion of the copper wiring layer, wherein the adhesion adhesion layer comprises a metal or a nitrogen-containing metal layer; in addition, the copper wiring is coated on the upper and side portions of the copper wiring. The layer is prevented, so the section is preferably trapezoidal. This 1305585

The 93042 TW outer copper wire layer may also be referred to as a core metal in the present invention. The diffusion suppression layer includes a nitrided M〇N and a nitrided nitride having an amorpnous structure. Among them, the adhesive layer is formed to have an amorphous structure _ Μ. Nitriding, _, titanium, and gasification. The invention provides a method for a lion to form a wiring substrate, the method comprising the steps of: depositing a substrate; and depositing and adhering a layer on the wire plate, the adhesion layer comprising a metal layer containing a nitrogen atom; and a deposition-sensitive line The layered layer of the layered layer ±, which looks for the ship county as a thief _ is the main component. The copper wiring layer is patterned to form a copper wiring layer pattern; the deposition-diffusion suppression layer, the diffusion (four) is disposed in the copper The wiring layer pattern and wherein the diffusion (4) is a nitrogen-containing metal layer; the diffusion suppression layer is patterned to be distributed on the upper portion and the side surface of the copper wiring layer pattern. The method for forming a transfer substrate, wherein the step of dispersing the film (4) comprises: applying a photoresist to the diffusion suppression layer; and performing back exposure of the copper wiring layer as a mask from the glass substrate side; When the photoresist is developed, the diffusion suppression layer has a photoresist coverage area and a photoresist exposure area; the diffusion suppression layer of the photoresist exposure area is surnamed. The method for forming a wiring substrate, wherein the step of etching the adhesion layer can be performed on the side step of the patterned copper compound and the side of the contact layer or on the side of the diffusion suppression (four) side step The etching process of attaching the adhesion layer is performed after the etching step of the suppression layer is performed. The method for forming a wiring substrate, wherein the adhesion adhesion layer or the diffusion suppression layer comprises titanium nitride having an amorphous structure, wherein the step of depositing the adhesion adhesion layer and the diffusion suppression layer comprises performing a nitrogen gas The step of reactive sputtering treatment in which the flow rate accounts for 5% to 3% of the total flow rate of argon gas plus nitrogen gas. The above method of forming a wiring substrate, wherein the adhesion adhesion layer or the diffusion suppression layer comprises molybdenum nitride having an amorphous structure. The step of depositing the adhesion adhesion layer and the diffusion suppression layer includes the step of performing a reactive sputtering treatment in which a nitrogen gas flow rate accounts for 30% or less of the total flow rate of the argon gas plus nitrogen gas. In addition, if the flow rate of nitrogen relative to the above-mentioned flow rate of the total sputtering gas is 〇%, at 1305585

93042TW In this case, reactive sputtering is carried out. In this specification, it is defined that the diffusion preventing layer and the dense layer are formed of molybdenum or titanium having an amorphous structure. The impedance of the wiring core metal has been greatly improved. In addition, the sheet resistivity can be reduced by half even if the wiring is laminated. By reducing the wiring delay caused by the impedance, it is possible to develop toward large-scale high definition and improve the aperture ratio. [Embodiment] An embodiment of the present invention will be described with reference to Fig. 1 . The present invention is a wiring board capable of suppressing copper diffusion, and can be applied to a panel in which a copper wiring layer is formed, particularly a liquid crystal display panel or an organic EL panel. As shown in Fig. 1 (a), the wiring board 1 可 which suppresses copper diffusion according to the present invention includes a substrate 1 2 ' and an adhesion adhesion layer 14 formed of a metal or a metal nitride film formed on the substrate 12, and is attached. The copper wiring layer 16 formed on the Φ layer and the diffusion suppressing layer 18 formed of the metal nitride film which is laminated on the upper portion and the side portion of the copper wiring layer 16 are formed, and another embodiment is shown in FIG. 1 ( b) the wiring substrate 5 可 which can suppress the copper diffusion of the present invention, or a substrate 5 2 and an adhesion layer 5 4 formed of a metal or metal nitride film formed on the substrate 52, and The copper wiring layer 5 形成 formed on the adhesion layer 504 is adhered, and the diffusion suppression layer 58 which is laminated on the upper portion of the copper wiring layer 615 is completed.

On the substrate 12 or 52, light-transmissive glass, quartz or the like is used. The substrate 12 or 52 of the following embodiment is exemplified by a glass substrate, and the present invention is not limited to the glass substrate, and other substrates may be used. The lower portion of the wiring 5 6 or 16 or the wiring itself can be formed as a metal film or a metal nitride film such as molybdenum Mo, molybdenum nitride m〇N, titanium Ti, titanium nitride TiN by a film formation method such as sputtering. The adhesion layer 14 or 5 4 or the diffusion suppression layer 18 or 58 is formed into a film. Providing the adhesion layer 14 or 54 is to increase the adhesion between the substrate 12 or 52 and the copper wiring layer 16 or 56, and to prevent ions in the substrate from diffusing to the copper wiring layer i 6 or 5 during the process. 6 internal influence into nature. Providing the diffusion suppressing layer 18 or 58 to prevent the copper wiring layer 1 or 65 from being formed into a film, and when the insulating film or the semiconductor layer is formed by a CVD apparatus, the copper wiring layer 丄6 or 5 6 is melted 1305585

The 93042TW low point causes the copper to diffuse into the semiconductor layer, and even worse, it is polluting its occupation. This diffusion suppression layer 18 or 58 is required to suppress the diffusion of the copper wiring layer. The diffusion of the copper wiring layer 16 or 5 6 _ gold is mainly caused by the diffusion between the interfaces of the contact layer copper wiring layer. Therefore, the wiring board of the present invention! In order to suppress the above-mentioned copper diffusion, it is necessary to use diffusion suppression of 6 or 5 6 which is a small woven and female amorphous structure to suppress the interfacial diffusion between the copper and the contact layer. The present invention proposes to control the nitrogen content of these lions by titanium nitride (10)), nitriding (_), etc., to control the nitrogen content of these lions, and to make a microscopic and dense amorphous structure without colliding with the ship line. Layer or electrode layer

8 or 5 8 〇 [Table 1] Table 1 below shows the steps of forming the wiring substrate 1 of Fig. 1(a) using the present invention, and the steps 1 to 7 and the guard steps 8 to u are described. Step content 1 - Wash 2 Splash money MoN 150A Cu 3000A 3 Photoresist coating 4 Exposure __ 5 6 Wet meal engraved PAN system 7 Resistor 53⁄4 8 9 —----- 10 S5 ~~~ - MoN 500A photoresist Paint i - back exposure. Development 1305585

93042TW 11 fishing 1 insect PAN system 12 photoresist peeling the wiring substrate 1 of the present invention 〇 before the engineering steps 1 to 7, including (1) preparing the glass substrate 1 2 and washing it, (2) coating the substrate 10 a bonding layer 14 made of a metal such as molybdenum nitride MoN or titanium nitride TiN or a metal nitride film, and a step of coating the copper layer (Cu) after the adhesion layer 14 is adhered, and (3) a layer of copper ( The step of performing the photoresist coating on the Cu layer, and (4) the step of exposing from the photoresist side, after the substrate 12 is irradiated, the light acts on the photoresist on the copper layer % (Cu). (5) a step of developing a copper wiring 16 pattern, and (6) performing an etching solution such as a PAN system (Phosphoric/Acetic/Nitric; phosphoric acid, acetic acid, nitric acid) to form a steel wiring layer 16 pattern. Step, (7) the step of stripping the photoresist. Further, the pre-engineering of the above-mentioned wiring board 1 is basically the same as the manufacturing process of manufacturing a wiring board by aluminum (A1) conventionally, and it is not necessary to introduce a new device. There are two points of change, that is, when the film type of the splash is changed from aluminum A1 or aluminum-arc alloy AiNd to copper Cu, and the composition of the etching wiring pAN is changed. Next, the engineering steps 8 to u in the subsequent stage of the wiring substrate of the present invention are described. The latter stage engineering includes (8) • using a diffusion suppression layer 18 8 formed of a metal nitride film formed of a molybdenum nitride MoN or a titanium nitride TiN on the copper wiring layer 16 to be sputtered. The step of applying the photoresist on the suppression layer 8 is carried out, (1 〇) from the side of the glass substrate, the copper Cu layer is used as a mask for the back surface exposure and then the steps are reduced, (the paste PAN is secretly secreted) The step of attaching the adhesion layer 14 to the diffusion suppression layer 18, and the step of (丄2) the lion photoresist. Figure 5 (a), (b), and (c) correspond to the above steps (8), ( 9) (丄〇), (丄^) The wiring board 1 of the present invention is a cross-sectional view, that is, Fig. 5 (a) is a complete coating and adhesion of the substrate 12 of the above steps (1) and (7) completed by the former engineering. The layer 14 is defined with a copper wiring layer 16 on the pattern of the hetero-diffusion inhibitor 8 as in step (8), and FIG. 5 (s) is shown in the diffusion suppression layer 1305585.

93042TW 1 8 is performed on the light Μ20 coating as step (9), and τ is applied to perform the reverse exposure of (i 〇) and (work 1) from the surface side of the glass substrate 12, because the back wiring is used, the copper wiring layer pattern 1 The 6-zone _exposure level, such as uv light, cannot pass, and the uv light of the surface wiring layer pattern area can pass, so that the light M 2 Q is made of the material, so that the unilluminated route layer pattern 丄 6 ' region is left over the diffusion suppression layer 1 8, so, when the fish is engraved with PAN-based money engraving. • As shown in Fig. 5(C), the photoresist layer 2 (10) and the PAN system are adhered as described above. The step of the adhesion layer 14 and the diffusion suppression layer 18 can be performed in the copper wiring layer 6 The pattern is completed by leaving only the diffusion suppression layer 18. The wiring substrate of the present invention manufactured according to the above description, wherein the step of attaching the adhesion layer 丄4 to the side may be engraved with the copper wiring layer 6 during the patterned copper wiring layer 丄6_etching step When the step of patterning the diffusion-inhibiting layer 18 is similar to the diffusion-suppressing layer, the diffusion-inhibiting layer is etched or after the diffusion-inhibiting layer is etched, the adhesion layer 14 is applied. Etching step. (Example 1) The amount of nitrogen (ν2) added during the reactive hetero-film formation of titanium (Ti) and titanium nitride (TiN) was changed, and structural analysis was carried out by a transmission electron microscope (ΤΕΜ). Among the crystals in which no nitrogen is added to form a % film, as shown in Fig. 2 U), a columnar crystal structure can be found. In the next reactive argon, nitrogen (n2) is added to the argon (Ar) gas to change the crystal structure. When the ratio of argon gas to N2 gas is 9 5 : 5, as shown in Fig. 2 (8), the above columnar crystal structure will be seen. If more nitrogen is added, the ratio of argon to n2 gas is 7 〇 : 3 0, and the columnar crystal structure of Fig. 2 (a) disappears. At this point, a compact, fine amorphous structure similar to Figure 2 (c) can be found. (Example 2) Next, 'the same as in the first embodiment', the specific resistance of titanium (Ti) and titanium nitride (TiN) which are ruthenium can be measured by changing the amount of nitrogen (N2) added during reactive sputtering. With surface roughness 1305585

93042TW (Rms) is shown as g 3. In the case where the diffusion suppressing layer (10) is in close contact with the layer, the ratio of the gas to the gas can be controlled to control the specific impedance and the surface roughness. It can be seen from Fig. 3 that the higher the ratio of helium, the higher the specific impedance but the lower the surface roughness, that is, the flatter; and the ratio of nitrogen to about 30% is a stable value of the specific impedance and surface roughness. Therefore, as shown in Fig. 3, if the helium flow rate accounts for only 5 to 30% of the total flow rate of argon gas plus nitrogen gas, a film having a desired impedance and a flat film can be sufficiently produced in this range. (Example 3) In the actual c* example 3, in order to understand the evaluation of the diffusion suppression property (barrier), the reliability test of dielectric breakdown under high % temperature and high pressure was carried out in this experiment, and the experimental conditions were at a temperature of 15 Under the condition of this, the SiN insulating film with a film thickness of 150 〇A and the test substance of this experiment were placed under an electric field to record that the SiN insulating film was diffused by the substance to be tested, resulting in a decrease in insulation. Time, its Fail time to simulate its diffusion inhibition ability. The test substance was prepared into a cylindrical test piece with an area of 1.3 4 6 mm 2 , and the test substance was (Mo) used as a control group, and the experimental group was respectively a copper (Cu) monomer, and the nitrogen addition amount was 30% (N 2 gas). It is a titanium nitride of 3 〇% of argon gas. As can be seen from Fig. 4, the nitrogen addition amount of 30% (the amount of nitrogen is only 3% of argon) of titanium nitride shows that it is better than the copper monomer and is better than the control group under the action of different electric fields (M〇 g is good or almost equivalent to the control (Mo), and it is proved to have sufficient effect of inhibiting diffusion. On the other hand, although not shown, titanium nitride having a nitrogen addition amount of less than 5% (the amount of nitrogen is only 5%) does not have an effect of suppressing diffusion. (Example 4) As shown in Table 2, a conventional Mo/AINd laminate structure was compared with a TiN/Cu/Ti laminate structure according to one embodiment of the present invention. For both configurations, the diffusion suppression layer and the core metal thickness ' are 5 〇 〇 A and 30,000 A, respectively. In addition, the adhesion adhesion layer of the TiN/Cu/Ti laminate structure is also the thickness of the ruthenium film, which is 150 Å. 138 1305585

93042TW [Table 2] Mo/AINd TiN/Cu/Ti Top Mo TiN Resistivity [Ε—6Ω . cm] 20 200 Thickness [A] 500 500 Core AlNd2% Cu Resistivity [Ε—6Ω · cm] 4.8 2.2 Thickness [A] 3000 3000 Bottom — Ti Resistivity [Ε—6Ω · cm] 0 200 Thickness [A] 0 150 Sheet Resistivity [m Ω /□] 153.8 73.2 According to Table 2, when the core metal is AINd, the specific impedance is 4.8 〇cm . In contrast, if the core metal is Cu, the specific impedance is 2. 2 y Qcm. As a result, the specific impedance of the wiring core metal is greatly improved. In addition, even if the wiring is used as a base structure, the sheet resistance is reduced by about half. The wiring of Mo/AINd has a sheet resistance of i 5 4ιηΩ/port. In contrast, % uses the base layer structure τwTi of the present invention, which is only 7 3 □, and is similarly lower than Μ〇/Α·. The wiring board according to the above-described invention and capable of suppressing the diffusion of copper has been described by way of example, but the wiring board of the present invention is not limited to the above embodiment. The core metal is a core metal layer of copper Cu < copper Cu as a main component, and the diffusion suppression layer and the adhesion adhesion layer are formed in either MoN or TiN. In the present invention, it is possible to prevent the implementation of the copper diffusion wiring board needle, and it is mainly to use the wiring board 1 (10) row and the main body of the wiring board 1 (10), but the wiring board 5 〇 or the like may be included. 14 8 ) 1305585 "―————

• 93042TW Takeuchi-.1 Qiu 3曰 Correction Replacement I In addition, the present invention can prevent the thickness of each layer of the wiring-layered structure of the copper diffusion wiring board, and is not limited to the thickness mentioned in the above-mentioned Example 4. The thickness of each layer is not particularly limited, and therefore, the thickness ratio of each layer of the laminated structure is not particularly limited. The manufacturing process of the present invention and the wiring board 5 (10) is roughly the same as that of the wiring board i. That is, the pre-engineering (2) of the wiring substrate 50 of the present invention is covered with an adhesion layer 504 made of a metal or a metal nitride film of MoN, Ti, TiN, Ti, etc., and then the copper layer is coated on the adhesion layer 504. The layer (〇〇5 6 'in this copper layer is stepped on with M〇N, TiN# metal or metal nitride film to tightly laminate the diffusion suppression layer 58. Next, through the above-mentioned work (3)~( 7), the wiring board 5 of the present invention as shown in Fig. 1(b) can be obtained by φ. In addition, the present invention can be made by each of the companies according to their own expertise without departing from the scope of the invention. Knowledge, improvement, correction, and change. The wiring board made of a copper wiring layer, especially the wiring board used for a liquid crystal television, a personal computer screen, and other displays, can apply the result of this invention. [FIG. 1] (a) 75 is a partial cross-sectional view of a wiring board capable of suppressing copper diffusion and forming a steel wiring layer, and (8) is a wiring board which can suppress the diffusion of steel according to another aspect of the present invention. Partial cross-sectional view of the copper wiring layer. • [Fig. 2] An analytical photograph of a cross-section of the wiring structure was taken by a transmission electron microscope (TEM). (a) It is a diffusion suppression of a film formed by adding no nitrogen (N2) during reactive splashing (7). 'The ratio of money to nitrogen is g 5 : 5 The diffusion-inhibiting layer (4) is a reactive inhibitor. The ratio of argon to nitrogen is 7 〇: 3 〇 The diffusion-suppressing layer is formed. 】 Change the ratio of argon to nitrogen to form a diffusion suppression layer of the film, which is a graph of the impedance and surface roughness (RTM5) measured value. [Fig. 4] In the dielectric breakdown life test, it is detected. The substance is copper ((5) monomer, nitrided 15; r 1305585

93042TW (ΤιΝ ‘% gas accounts for only 33% of Ar gas) and molybdenum (M〇) electrode, according to the input insulation failure life of each test substance and the electric field of each material. [Fig. 5] (a) is a cross-section of the wiring layer forming portion of the present invention, the wiring layer which can suppress the fine diffusion, and the wiring layer of the manufacturing step (8). (8) is a cross-sectional view showing a portion in which the thin layer is formed in the process step (10) which is related to the present invention and which suppresses the diffusion of copper. (c) is a cross-sectional view of the portion of the thin layer of the film with the = phase, the suppressable _ _ _ substrate, and the _ ( i i ). [Fig. 6] A diagram of a defective wiring structure. DESCRIPTION OF SYMBOLS 1〇, 5 0 : Wiring board 12 and 5 2 · Substrate 14 and 5 4 : Adhesive adhesion layer 16 and 56 : Copper wiring layer (core metal) 18 , 5 8 : Diffusion suppression layer 2 0 : Light Resistance layer

Claims (1)

, I3〇5585 93042TW X. Patent application scope: h-type wiring substrate, comprising: a substrate, and a copper wiring layer, wherein the copper wiring layer is disposed above the substrate, wherein the copper wiring layer is steel or copper as a main component; A diffusion suppression layer '3H diffusion suppression layer is disposed on the upper and side faces of the copper wiring layer, and the 扩散 diffusion suppression layer is a nitrogen-containing metal' wherein the diffusion suppression layer and the copper wiring layer form a trapezoidal cross-sectional structure. A wiring board comprising: a substrate; and a copper wiring layer disposed on the substrate, wherein the copper wiring layer is copper or copper as a main component; and an adhesion layer is disposed on the substrate a lower portion of the copper wiring layer, wherein the adhesion adhesion layer comprises a metal or a nitrogen-containing metal layer; a diffusion suppression layer disposed on an upper portion and a side surface of the copper wiring layer, and the diffusion suppression layer is a nitrogen-containing metal The diffusion suppression layer, the adhesion adhesion layer and the copper wiring layer form a trapezoidal cross-sectional structure. 3. The wiring substrate according to claim 1 or claim 2, wherein the diffusion inhibiting layer comprises a nitrided steel MoN having an amorphous structure, and a TiN. The wiring board according to claim 2, wherein the adhesion adhesion layer comprises molybdenum Mo, molybdenum nitride m〇N, titanium Ti, and titanium iodide having an amorphous structure. 17 1305585 93042TW 5. A method for forming a wiring substrate, the method comprising: preparing a substrate; depositing an adhesion layer on the substrate, the adhesion layer comprising a metal or a metal layer containing nitrogen; depositing a copper wiring a layer on the adhesion layer, wherein the copper wiring layer is copper or copper as a main component; the copper wiring layer is patterned to form a copper wiring layer pattern; Depositing a diffusion suppression layer disposed on the copper wiring layer pattern and wherein the diffusion suppression layer is a nitrogen-containing metal layer; patterning the diffusion suppression layer to be distributed over the copper wiring layer pattern a side surface, wherein the patterned diffusion suppression layer and the copper wiring layer pattern form a trapezoidal cross-sectional structure. 6. The method of claim 5, wherein the step of diffusing the diffusion inhibiting comprises: coating a photoresist on the diffusion inhibiting layer; using the copper wiring layer as a mask from the side of the glass substrate Performing backside exposure; thinning the photoresist, _ suppressing (4) the silk coverage area and the exposed area; etching the diffusion suppression layer of the photoresist exposed area. 7. The method of claim 5, wherein the step of attaching the adhesion layer is performed by the side of the patterned copper wiring layer and the layer of the ship layer The _transition time of the layer and the diffusion suppression are initiated by _, or after the scatter of the diffusion suppression layer _ after the _ _ close layer _ engraving step. The method of claim 5, wherein the adhesion adhesion layer or the diffusion suppression layer comprises an amorphous structure. 9. The method of claim 8, wherein the step of depositing the adhesion layer and the diffusion inhibiting layer comprises performing a nitrogen flow rate of 5% to 30% of the total flow rate of the argon gas plus nitrogen. /〇, the step of reactive rhodium plating. 10. The method according to claim 5, wherein the adhesion layer or the diffusion suppression layer comprises a molybdenum nitride having an amorphous structure. 11. The method according to claim 10, wherein the step of depositing the adhesion adhesion layer and the diffusion suppression layer comprises performing a reactive sputtering with a nitrogen flow rate of 3% or less of a total flow rate of argon gas plus nitrogen gas. The steps of mine treatment. 12. The wiring substrate according to claim 1, wherein the side surface of the copper wiring layer is an inclined surface. 13. The wiring substrate according to the application scope, wherein the substrate forms a pure angle with the diffusion suppressing layer formed on the side surface. H. The wiring substrate of claim 1, wherein the diffusion inhibiting layer is a claw light permeable material. 19