JP7196372B2 - LAMINATED STRUCTURE AND METHOD FOR MANUFACTURING LAMINATED STRUCTURE - Google Patents

Description

The present invention relates to a laminated structure in which a first titanium layer, an aluminum layer, and a second titanium layer are sequentially laminated, and a method for manufacturing the laminated structure.

Laminated structures of this type are used as source/drain electrodes of switching elements (thin film transistors) in electronic devices such as displays, smartphones, and electronic paper (see, for example, Patent Document 1). On the other hand, with the development of flexible electronic devices in recent years, there has been a demand for high bending resistance for laminated structures having relatively high-hardness titanium layers.

In general, a titanium layer and an aluminum layer of a laminated structure are consistently formed by a sputtering method in a vacuum atmosphere (see, for example, Patent Document 1). For example, when forming a titanium layer or an aluminum layer, after evacuating a vacuum chamber in which a titanium or aluminum target and a substrate are arranged to face each other to a predetermined pressure, a rare gas (for example, argon) is introduced into the vacuum chamber. gas) is introduced, DC power with a negative potential is applied to the target to form plasma, the target is sputtered by ionized noble gas ions in the plasma, and the sputtered particles scattered from the target adhere to the substrate. , to form a titanium layer or an aluminum layer with a desired film thickness (eg, a first titanium layer of 50 nm, an aluminum layer of 500 nm, and a second titanium layer of 50 nm). At this time, various sputtering conditions such as input power to the target, amount of rare gas introduced, and total pressure in the vacuum chamber during film formation are set in consideration of productivity and film thickness distribution (for example, input power 20-40 kW, total pressure 0.2-1.0 Pa).

Here, in order to confirm the bending resistance of the laminated structure, a test substrate having a predetermined shape was used, and a first titanium layer, an aluminum layer, and a second titanium layer were sequentially formed on the surface of the test substrate under predetermined sputtering conditions. After lamination, when a tensile test was performed on the laminated structure peeled from the test base material, the laminated structure elongated by more than double just by applying a tensile load necessary to give an elongation amount of 5%. It has been found. Further, when the state of the surface of the laminated structure (that is, the surface of the titanium layer) after the tensile test was observed, it was found that many cracks extending in the thickness direction were generated in the titanium layer. Therefore, the present inventors have made intensive studies and found that the crystal structure has a crystal structure in which relatively small crystal grains are aligned in the film thickness direction and the crystal grain boundaries are connected so as to extend in the film thickness direction. It was discovered that when hard and brittle titanium compounds such as titanium nitride and titanium oxide were formed at the grain boundaries due to impurities such as nitrogen molecules and oxygen molecules taken into the layers, the laminated structure could not obtain strong bending resistance. I came to do it.

JP 2015-177105 A

The present invention has been made based on the above findings, and an object of the present invention is to provide a laminated structure having strong bending resistance and a method for producing the laminated structure.

In order to solve the above problems, a laminated structure of the present invention in which a first titanium layer, an aluminum layer, and a second titanium layer are laminated in this order is provided. It has a crystal structure with diffraction peaks on the (002) plane and the (100) plane in the Miller index measured by diffraction measurement, the half width of the diffraction peak on the (002) plane is 1.0 deg or less, and the (100) plane The diffraction peak has a half width of 0.6 deg or less. In this case, the aluminum layer preferably has a crystal structure having a diffraction peak in the (111) plane in the Miller index measured by X-ray diffraction.

Further, in order to solve the above problems, a method for manufacturing a laminated structure according to the present invention for producing a laminated structure in which a first titanium layer, an aluminum layer, and a second titanium layer are sequentially laminated includes a sputtering method. A first step of forming a first titanium layer on the base material, a second step of forming an aluminum layer on the first titanium layer, and a second titanium layer on the aluminum layer by In each of the first and third steps, the partial pressure of nitrogen gas is 3.0 × 10 ^-4 Pa or less and the partial pressure of oxygen gas is 9.0 × 10 ^-5 Pa. Thereafter, the titanium target and the substrate were placed until the partial pressure of water vapor gas reached 8.0×10 ⁻⁴ Pa or less and the partial pressure of hydrogen gas reached 5.0×10 ⁻⁵ Pa or less. An evacuation step of evacuating the inside of the vacuum chamber, introducing a rare gas so that the total pressure in the vacuum chamber is maintained within the range of 0.2 Pa to 0.5 Pa, and applying a predetermined power to the titanium target. and a film forming step of forming the first and second titanium layers at a film forming rate within the range of 3 nm/sec to 5 nm/sec. In this case, the second step includes introducing a rare gas such that the total pressure in the vacuum chamber in which the aluminum target and the base material are arranged is maintained within a range of 0.2 Pa to 0.5 Pa, It is preferable to further include a film forming step of applying a predetermined electric power to a target made of aluminum to form an aluminum layer at a film forming rate within the range of 7 nm/sec to 10 nm/sec.

According to the above, prior to depositing the first titanium layer, the aluminum layer, and the second titanium layer in the vacuum chamber in a vacuum atmosphere, an impurity gas (for example, nitrogen gas) is introduced into the vacuum chamber. , oxygen gas, water vapor gas, and hydrogen gas) is evacuated until the partial pressure reaches a predetermined value or less, whereby titanium compounds such as titanium nitride and titanium oxide are formed at the grain boundaries of the first and second titanium layers. formation is suppressed as much as possible. Then, when the first and second titanium layers are formed, if the film formation rate is set within the range of 3 nm/sec to 5 nm/sec, the first and second titanium layers can be formed with a large grain size. It can have a crystal structure in which the crystal grains overlap irregularly in the film thickness direction and the crystal grain boundaries do not connect in the film thickness direction.

When the titanium layer formed as described above was subjected to X-ray diffraction, a diffraction peak on the (002) plane and a diffraction peak on the (100) plane were confirmed. The intensity ratio of diffraction peaks on the 100) plane was 0.20 or more. At this time, the half-value width of the diffraction peak on the (002) plane is 1.0 deg or less, and the half-value width of the diffraction peak on the (100) plane is 0.6 deg or less. This suppresses the formation of a titanium compound at the crystal grain boundaries of the first and second titanium layers, and crystal grains having a large grain size overlap unevenly in the film thickness direction, preventing the crystal grain boundaries from connecting. It has a crystal structure. Further, even when a tensile load necessary to give an elongation of 5% or 10% is applied to the laminated structure similar to the above, the elongation of the laminated structure is suppressed to within 10%, and Observation of the surface of the laminated structure after the tensile test also confirmed that no cracks occurred. As a result, the laminate structure of the present invention has a higher resistance to bending than that of the conventional example.

BRIEF DESCRIPTION OF THE DRAWINGS The figure which illustrates typically the laminated structure of embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS The figure which illustrates typically the sputtering apparatus which enforces the manufacturing method of the laminated structure of embodiment of this invention. FIG. 3 is a diagram schematically explaining a film forming chamber Pc1 shown in FIG. 2; The graph which shows the experimental result which confirms the effect of this invention. 4(a) to 4(c) are diagrams for schematically explaining the crystal structures of titanium layers deposited in Comparative Experiments 1 to 3. FIG.

Hereinafter, embodiments of the laminated structure and the method for manufacturing the laminated structure of the present invention will be described with reference to the drawings.

As shown in FIG. 1, in the laminated structure LS of the present embodiment, the substrate Sw is made by attaching a polyimide film Pf to the surface of a glass substrate Sg (separable at the interface between the glass substrate Sg and the polyimide film Pf). ), a first titanium layer L1, an aluminum layer L2, and a second titanium layer L3 are formed (stacked) in sequence on the surface of the substrate Sw consistently by sputtering in a vacuum atmosphere.

As shown in FIG. 2, the sputtering apparatus Sm that can be used for film formation of the laminated structure LS is of a so-called cluster tool type, and includes a central transfer chamber Tc having a transfer robot R. Then, through the gate valve Gv, a load lock chamber Lc, a vacuum chamber (hereinafter referred to as "deposition chamber") Pc1 for depositing a first titanium layer L1, and a deposition for depositing an aluminum layer L2. The chamber Pc2 and the deposition chamber Pc3 for depositing the second titanium layer L3 are connected to each other. Here, since the same structural parts are provided in the deposition chambers Pc1, Pc2, and Pc3 except for the targets used, the deposition chamber Pc1 will be described as an example with reference to FIG. The chamber Pc1 is connected to an exhaust pipe 11 leading to a vacuum pump unit Pu composed of a turbomolecular pump, a rotary pump, or the like, and the film formation chamber Pc1 is evacuated to a predetermined degree of vacuum (eg, 1×10 ⁻⁶ Pa). can be done. A gas pipe 13 in which a mass flow controller 12 is interposed is connected to the side wall of the vacuum chamber Pc1, and a rare gas (for example, argon gas) whose flow rate is controlled can be introduced into the deposition chamber Pc1. A target 2 made of titanium (a target made of aluminum in the film formation chamber Pc2) is arranged in the upper part of the film formation chamber Pc1 so as to face the substrate Sw, and a known magnet unit 3 is arranged above it. .

The titanium target 2 has a purity of 99.9% or higher, and the aluminum target has a purity of 99.99% or higher. An output from a sputtering power source Ps is connected to the target 2 , and DC power having a negative potential can be supplied to the target 2 . A stage 4 is arranged in the lower part of the film forming chamber Pc1 so as to face the target 2, and the substrate Sw can be placed thereon. The deposition chamber Pc1 is provided with a measuring instrument 5 for measuring the total internal pressure and the partial pressures of impurity gases (for example, nitrogen gas, oxygen gas, water vapor gas, and hydrogen gas). Known devices such as an ionization vacuum gauge and a mass spectrometer can be used as such a measuring device 5, so further explanation is omitted. A method for manufacturing the laminated structure LS by the sputtering apparatus Sm will be specifically described below.

The substrate Sw is put into the load-lock chamber Lc in the atmosphere, and the load-lock chamber Lc is evacuated. Prior to loading the substrate Sw into the load lock chamber Lc, the transfer chamber Tc and each of the film forming chambers Pc1, Pc2, and Pc3 are previously evacuated to a predetermined pressure (1×10 ⁻³ Pa) and are in a standby state. ing. When the substrate Sw is placed on the stage 4 of the deposition chamber Pc1, the evacuation is continued, and the partial pressure of the nitrogen gas measured by the mass spectrometer 5 is 3.0 × 10 ^-4 Pa or less, and the oxygen gas film formation until the partial pressure of 9.0 × 10 ^-5 Pa or less, the partial pressure of water vapor gas reaches 8.0 × 10 ^-4 Pa or less, and the partial pressure of hydrogen gas reaches 5.0 × 10 ^-5 Pa or less. The inside of the chamber Pc1 is evacuated (evacuation step of the first step).

Next, when the partial pressure of each gas becomes equal to or less than a predetermined value, argon gas is introduced into the evacuated deposition chamber Pc1 so that the total pressure is maintained within the range of 0.2 Pa to 0.5 Pa. is introduced, and 20 kW to 30 kW of DC power having a negative potential is applied to the target 2 from the sputtering power source Ps. Then, plasma is formed in the deposition chamber Pc1. The target 2 is sputtered by argon gas ions ionized in the plasma. As a result, the sputtered particles scattered from the target 2 adhere to and accumulate on the film formation surface (polyimide film Pf) of the base material Sw, and the first titanium layer L1 is formed on the base material Sw at a rate of 3 nm/sec to 5 nm/sec. The film is formed at the film speed (film formation step in the first step). At this time, the sputtering time is appropriately set so that the thickness of the first titanium layer L1 is, for example, 10 nm to 50 nm.

After completion of the first step, the substrate Sw is transported to the film forming chamber Pc2, and an evacuation step is performed in the same manner as in the first step. When the partial pressure of each gas becomes equal to or less than a predetermined value, argon gas is introduced into the evacuated deposition chamber Pc2 so that the total pressure is maintained within the range of 0.2 Pa to 0.5 Pa. , DC power of 30 kW to 40 kW having a negative potential is applied to the target 2 made of aluminum from the sputtering power source Ps. Then, plasma is formed in the deposition chamber Pc2, and the sputtered particles scattered from the target 2 adhere and deposit on the surface of the first titanium layer L1, forming an aluminum layer L2 of 7 nm/sec on the first titanium layer L1. A film is formed at a film formation rate of ~10 nm/sec (film formation step in the second step). At this time, the sputtering time is appropriately controlled so that the thickness of the aluminum layer L2 is, for example, 200 nm to 800 nm.

After completion of the second step, the substrate Sw is transported to the film forming chamber Pc3, and an evacuation step is performed in the same manner as in the first step. When the partial pressure of each gas becomes equal to or less than a predetermined value, the second titanium layer L3 is formed on the aluminum layer L2 at a film formation rate of 3 nm/sec to 5 nm/sec under the same sputtering conditions as in the first step. A film is formed (film formation step in the third step). At this time, the film thickness of the second titanium layer L3 is set to the same film thickness (for example, 10 to 50 nm) as the first titanium layer L1 by appropriately controlling the sputtering time.

When the laminated structure LS is manufactured as described above, the introduction of impurities into the titanium layers L1 and L3 is suppressed as much as possible, and titanium compounds such as titanium nitride and titanium oxide are formed at the grain boundaries Cf. (See the part enclosed by the dashed line in FIG. 1). In addition, by forming the titanium layers L1 and L3 at a film formation rate within the range of 3 nm/sec to 5 nm/sec, the grain size of the crystal grains Cg becomes larger than that of the conventional example, and moreover, , these crystal grains Cg overlap irregularly in the film thickness direction, and as a result, a crystal structure in which the crystal grain boundaries Cf are not connected in the film thickness direction can be obtained (see FIG. 1). When the X-ray diffraction of the titanium layers L1 and L3 was measured, a diffraction peak on the (002) plane and a diffraction peak on the (100) plane were confirmed, and a diffraction peak on the (002) plane was confirmed. The intensity ratio of the diffraction peak on the (100) plane to the peak was 0.20 or more. At this time, the half width of the diffraction peak on the (002) plane was 1.0 deg or less, and the half width of the diffraction peak on the (100) plane was 0.6 deg or less.

Next, in order to confirm the above effect, the following experiment was conducted using the sputtering apparatus Sm.

In the invention experiment, the substrate Sw is assumed to be a glass substrate Sg with a polyimide film Pf attached on its upper surface, and after the substrate Sw is placed on the stage 4 of the deposition chamber Pc1, the nitrogen gas measured by the mass spectrometer 5 is 1.0×10 ⁻⁴ Pa, the partial pressure of oxygen gas is 8.0×10 ⁻⁵ Pa, the partial pressure of water vapor gas is 5.0×10 ⁻⁴ Pa, and the partial pressure of hydrogen gas is 5 Evacuation was performed until the pressure reached 0×10 ⁻⁵ Pa (first step, evacuation step). At this time, the total pressure in the vacuum chamber Pc1 was 7.3×10 ⁻⁴ Pa. After the evacuation process, argon gas is introduced into the vacuum chamber Pc1 at a flow rate of 120 sccm so that the total pressure in the vacuum chamber Pc1 is maintained at 0.3 Pa, and at the same time, a DC power of 20 to 30 kW is applied to the target 2. Then, the titanium target 2 was sputtered to form a first titanium layer L1 with a film thickness of 50 nm on the surface of the substrate Sw at a film formation rate of 3 nm/sec (first film formation step). The solid line in FIG. 4 shows the result of measuring the X-ray diffraction of the deposited first titanium layer L1. Also referring to Table 1, a diffraction peak on the (002) plane is confirmed near the diffraction angle (2θ) of 38 to 39°, and a diffraction peak on the (100) plane is confirmed near the diffraction angle of 35 to 36°. The intensity ratio of the diffraction peak on the (100) plane to the diffraction peak on the (002) plane is 0.25, the half width of the diffraction peak on the (002) plane is 0.5 deg, and the half width of the diffraction peak on the (100) plane is 0.25. The price range was 0.6deg. After the first step, the substrate Sw is transported to the film forming chamber Pc2, and after performing the evacuation step in the same manner as in the first step, argon is supplied so that the total pressure in the film forming chamber Pc2 is maintained at 0.3 Pa. A gas is introduced into the film formation chamber Pc2 at a flow rate of 120 sccm, and at the same time, DC power of 35 to 40 kW is applied to the target 2 made of aluminum to sputter the target 2, and the first film is formed at a film formation rate of 7 nm/sec. An aluminum layer L2 having a film thickness of 500 nm was formed on the titanium layer L1. When the X-ray diffraction of the deposited aluminum layer L2 was measured, a diffraction peak on the (111) plane was confirmed near the diffraction angle (2θ) of 38 to 39°. After the second step, the substrate Sw is transported to the film forming chamber Pc3, and the evacuation step is performed in the same manner as in the first step. A second titanium layer L3 having a thickness of 50 nm was formed on the aluminum layer L2, thereby obtaining a laminated structure LS. When the X-ray diffraction of the deposited second titanium layer L3 was measured, a diffraction pattern (see FIG. 4) similar to that of the first titanium layer L1 was obtained. Then, in order to confirm the bending resistance of the laminated structure LS thus obtained, a test substrate (polyimide film Pf) having a known shape (width 5 mm, length 20 mm, thickness 0.02 mm) was placed on a glass. After forming on the substrate Sg and successively laminating the first titanium layer L1, the aluminum layer L2, and the second titanium layer L3 on the surface of the test substrate under the sputtering conditions described above, the interface between the glass substrate Sg and the polyimide film Pf A tensile test (tensile speed: 0.5 mm/min) was performed using a tensile tester ("STA-1150" manufactured by ORIENTEC) on the laminated structure LS obtained by peeling in . It was confirmed that the elongation of the laminated structure can be suppressed to within 10% (5%, 8%) even if a tensile load required to give an elongation of 10% is applied. In addition, the resistance R when a tensile load that gives an elongation of 5% and 10% is applied is measured using a resistance measuring instrument ("AD7461A" manufactured by ADVANTEST), and the resistance R0 when no tensile load is applied. When the resistance increase rate (=(R−R0)/R0) was determined, it was confirmed that it could be suppressed within 10% (5%, 8%). Moreover, when the surface state of the laminated structure LS after the tensile test was observed using a commercially available microscope, it was confirmed that no cracks occurred. From these results, it was found that the laminated structure LS obtained in the experiment of the present invention has a higher bending resistance than that of the conventional example.

(Table 1)

Next, the following comparative experiment was conducted for comparison with the above invention experiment. In Comparative Experiment 1, the above invention was used except that the total pressure in the film formation chamber Pc1 was maintained at 0.6 Pa and the film formation rate was 2 nm/sec in the film formation steps of the first and third steps. A laminated structure LS was obtained in the same manner as in the experiment. When a tensile test was performed under the same conditions as the above invention experiment, it was confirmed that the elongation amount of the laminated structure LS was more than doubled. Further, when the rate of increase in resistance was obtained in the same manner as in the experiment of the invention, it was 30% and 400%. Further, when the surface state of the laminated structure LS after the tensile test was observed in the same manner as in the above invention experiment, it was confirmed that cracks were generated and whitened. From these results, it was found that the laminated structure LS obtained in Comparative Experiment 1 had weak bending resistance. When the X-ray diffraction of the first titanium layer L1 formed in Comparative Experiment 1 was measured, no diffraction peak was observed on the (100) plane, as indicated by the dashed line in FIG. ) plane was confirmed, and the half width of the diffraction peak on the (002) plane was 0.9 deg. In the case of having such a diffraction pattern, as shown in FIG. 5A, it has a crystal structure in which small crystal grains Cg are aligned in the film thickness direction and crystal grain boundaries Cf are connected so as to extend in the film thickness direction. Then it is inferred.

In Comparative Experiment 2, the laminated structure LS was obtained in the same manner as in the Experiment of the Invention except that the first and third steps did not perform the evacuation step (only the film formation step was performed). rice field. That is, when the total pressure in the vacuum chamber Pc1 reached a predetermined degree of vacuum (2.8×10 ⁻³ Pa), the rare gas was introduced into the vacuum chamber Pc1 regardless of the partial pressure of the impurity gas. When the partial pressure of the impurity gas at this time was measured, the partial pressure of the nitrogen gas was 5.0×10 ⁻⁴ Pa, the partial pressure of the oxygen gas was 2.0×10 ⁻⁴ Pa, and the partial pressure of the water vapor gas was 2. 0×10 ⁻³ Pa, and the partial pressure of hydrogen gas was 5.0×10 ⁻⁵ Pa, which were below the standard values except for hydrogen gas. When a tensile test was performed under the same conditions as the above invention experiment, it was confirmed that the elongation amount of the laminated structure LS was more than doubled. Further, when the rate of increase in resistance was obtained in the same manner as in the experiment of the invention, the results were 120% and 650%, which are even worse than those in the comparative experiment 1. Further, when the surface state of the laminated structure LS after the tensile test was observed in the same manner as in the above invention experiment, it was confirmed that cracks were generated and whitened. From these results, it was found that the laminated structure LS obtained in Comparative Experiment 2 had weak bending resistance. When X-ray diffraction of the formed first titanium layer L1 was measured, a diffraction peak was observed not only for the (002) plane but also for the (100) plane. The intensity ratio of the diffraction peak in the (100) plane to the diffraction peak in the (100) plane was 0.11, which is less than 0.20. Also, the half width of the diffraction peak on the (100) plane was 0.7 deg, which is larger than 0.6 deg. In the case of having such a diffraction pattern, as shown in FIG. 5B, it is presumed that a titanium compound Im such as titanium nitride or titanium oxide is formed at the grain boundary Cf.

In Comparative Experiment 3, the total pressure in the film forming chambers Pc1 and Pc3 during the film formation in each of the first and third steps was maintained at 0.6 Pa and the film forming rate was set to 2 nm/sec. A laminated structure LS was obtained in the same manner as in the experiment of the invention, except that the evacuation step was not performed in each of the third steps (only the film formation step was performed). When a tensile test was performed under the same conditions as the above invention experiment, it was confirmed that the elongation amount of the laminated structure LS was more than doubled. In addition, when the rate of increase in resistance was obtained in the same manner as in the experiment of the invention, it was 300% and 900%, which is worse than that of the comparative experiment 2. Further, when the surface state of the laminated structure LS after the tensile test was observed in the same manner as in the above invention experiment, it was confirmed that cracks were generated and whitened. From these results, it was found that the laminated structure LS obtained in Comparative Experiment 3 had weaker bending resistance than Comparative Experiments 1 and 2 described above. When the X-ray diffraction of the first titanium layer L1 formed in Comparative Experiment 3 was measured, no diffraction peak on the (100) plane was confirmed, and only a diffraction peak on the (002) plane was confirmed. The half width of the diffraction peak on the (002) plane was 0.8 deg. When having such a diffraction pattern, as shown in FIG. 5(c), it has a crystal structure in which small crystal grains Cg are aligned in the film thickness direction and crystal grain boundaries Cf are connected so as to extend in the film thickness direction. Moreover, it is presumed that the titanium compound Im is formed at the grain boundaries Cf.

Although the embodiments of the present invention have been described above, various modifications are possible without departing from the scope of the technical idea of the present invention. In the above-described embodiment, the laminated structure LS is described as an example in which the first titanium layer L1, the aluminum layer L2, and the third titanium layer L3 are laminated. The present invention can also be applied to laminated layers.

Further, in the above embodiment, the substrate Sw is transferred in-situ among the film forming chambers Pc1, Pc2, and Pc3, and the first titanium layer L1, the aluminum layer L2, and the second titanium layer L3 are formed in a vacuum atmosphere. However, the present invention is not limited to this, and the present invention can also be applied to the case where the first and second titanium layers L1 and L3 and the aluminum layer L2 are formed by different sputtering apparatuses. can be applied. Also, the first titanium layer L1 and the second titanium layer L3 may be formed in the same film formation chamber.

LS... Laminated structure, L1... First titanium layer, L2... Aluminum layer, L3... Second titanium layer, Sw... Base material, Pc1, Pc2, Pc3... Film formation chamber (vacuum chamber), 2... Target.

Claims (4)

In a laminated structure in which a first titanium layer, an aluminum layer, and a second titanium layer are sequentially laminated,
Each of the first and second titanium layers has a crystal structure with diffraction peaks in the (002) plane and the (100) plane in the Miller index measured by X-ray diffraction, and half of the diffraction peak in the (002) plane A laminated structure having a value width of 1.0 deg or less and a diffraction peak half width of 0.6 deg or less on the (100) plane. 2. The laminated structure according to claim 1, wherein said aluminum layer has a crystal structure having a diffraction peak in the (111) plane in the Miller index measured by X-ray diffraction. In a method for manufacturing a laminated structure in which a first titanium layer, an aluminum layer, and a second titanium layer are sequentially laminated,
A first step of forming a first titanium layer on a substrate by a sputtering method, a second step of forming an aluminum layer on the first titanium layer, and a second titanium layer on the aluminum layer a third step of depositing a layer;
In each of the first and third steps, the partial pressure of nitrogen gas is 3.0×10 ⁻⁴ Pa or less, the partial pressure of oxygen gas is 9.0×10 ⁻⁵ Pa or less, and the partial pressure of steam gas is 8.0×10 −5 Pa or less. Evacuation step of evacuating the vacuum chamber in which the titanium target and the substrate are arranged until the partial pressure of hydrogen gas reaches 0×10 ⁻⁴ Pa or less and the hydrogen gas partial pressure reaches 5.0×10 ⁻⁵ Pa or less, respectively. Then, a rare gas is introduced so that the total pressure in the vacuum chamber is maintained within the range of 0.2 Pa to 0.5 Pa, and a predetermined power is applied to the titanium target to achieve 3 nm/sec to 5 nm/sec. and a film forming step of forming the first and second titanium layers at a film forming rate within a range. In the second step, a rare gas is introduced so that the total pressure in the vacuum chamber in which the aluminum target and the substrate are arranged is maintained within a range of 0.2 Pa to 0.5 Pa, and the aluminum 4. The manufacturing of the laminated structure according to claim 3, further comprising a film forming step of applying a predetermined power to the target and forming the aluminum layer at a film forming rate within a range of 7 nm/sec to 10 nm/sec. Method.

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