JP6380837B2 - Sputtering target material for forming coating layer and method for producing the same - Google Patents

Description

  The present invention relates to a sputtering target material for forming a coating layer used for forming a coating layer on a thin film layer made of Cu or Cu alloy, which becomes a main wiring of an electronic component, for example, and a method for manufacturing the same.

  Electrophoretic type used in liquid crystal display (Liquid Crystal Display: hereinafter referred to as “LCD”), plasma display panel (Plasma Display Panel: hereinafter referred to as “PDP”), electronic paper, etc. for forming a thin film device on a glass substrate In addition to flat display devices such as displays (flat panel displays; hereinafter referred to as “FPD”), thin film electronic components such as various semiconductor devices, thin film sensors, and magnetic heads require wiring films with low electrical resistance. It is. For example, FPDs such as LCDs, PDPs, and organic EL displays are required to have low resistance in their wiring films in accordance with large screens, high definition, and high speed response. In recent years, new products such as a touch panel for adding operability to the FPD and a flexible FPD using a resin substrate have been developed.

In recent years, it is necessary to reduce the resistance of a wiring film of a thin film transistor (hereinafter referred to as “TFT”) used as a driving element of an FPD, and the material of the main wiring thin film layer is lower than that of conventional Al. Studies are underway to change to resistive Cu.
In addition, the touch panel substrate screen that provides direct operability while viewing the screen of the FPD is also increasing in size, and a thin film layer made of Cu or Cu alloy having a lower resistance than Al (hereinafter referred to as “Cu thin film layer”). Studies are underway to use as the main wiring thin film layer.
Generally, indium tin oxide (hereinafter referred to as “ITO”), which is a transparent conductive film, is used as a position detection electrode of a touch panel used in a portable terminal, a tablet PC, or the like. . Cu can be contacted with ITO, but has low adhesion to the substrate and poor weather resistance. For this reason, in order to ensure the adhesion of the Cu thin film layer and to improve the weather resistance, it is necessary to form a laminated wiring film in which the Cu thin film layer is coated with a coating layer such as a Ni alloy.

  On the other hand, a sputtering method using a sputtering target material is optimal as a method for forming the above-described thin film wiring. Sputtering is one of the physical vapor deposition methods, and it is a method that can stably form a large area as compared with other vacuum vapor deposition and ion plating, and an excellent thin film layer with little composition fluctuation is obtained. It is an effective technique.

Since Ni, which is the main component in the coating layer, is a magnetic substance at room temperature, in the magnetron sputtering apparatus generally used in FPD applications, the sputtering target material absorbs the magnetic flux of the magnetic circuit and is stable efficiently. Difficult to perform sputtering.
In response to such a problem, the applicant of the present invention uses 1 to 25 atomic% of Cu as a coating layer for a thin film layer of Ag or Cu, and further includes Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W. A multilayer wiring film using a Ni alloy having 1 to 25 atomic% of selected elements and a total addition amount of 35 atomic% or less is proposed. (Patent Document 1)
The coating layer proposed in Patent Document 1 is weakly magnetized by using a Ni alloy to which a predetermined amount of transition metals such as Ti, V, and Cr are added, so that film formation by sputtering can be performed stably and for a long time. This is a useful technology in terms of points.
Further, for the purpose of improving the etchability of the Ni alloy coating layer with respect to the Cu etchant, a Ni—Cu alloy in which Cu is added to Ni in an amount of 25 to 45 wt. A Ni—Cu alloy in which Fe or Mn is added to 5 wt% or less to a Ni—Cu alloy added to ˜25 wt% has been proposed. (Patent Document 2)
Similarly, for the purpose of improving etching properties and improving weather resistance and adhesion to a Cu etchant, Ni—Cu alloy mainly containing 15 to 55 wt% of Cu and Ni—Cu containing 10 wt% or less of Cr and Ti are mainly used. Cu-based alloys have been proposed. (Patent Document 3)
These Ni—Cu alloys disclosed in Patent Document 2 and Patent Document 3 are useful techniques in that each can improve etching properties.

JP 2006-310814 A JP 2011-052304 A JP 2012-193444 A

In recent years, FPDs are rapidly increasing in definition, and therefore it is desired to perform etching with a narrower wiring width with high accuracy. However, since Cu is not easy to perform dry etching, which is a highly accurate etching method, wet etching is mainly used in FPD applications.
However, there is a problem in that a residue is easily generated when a laminated wiring film composed of a Cu thin film layer and the coating layer is wet-etched. For this reason, the residue is suppressed by over-etching using an etchant to which highly volatile hydrogen peroxide is added. However, the amount of side etching increases, and the wiring film with a narrow width expected in the future can be stabilized. It has become clear that there are issues that are difficult to obtain.

According to the study of the present inventor, when the laminated wiring film formed of the Cu thin film layer and the coating layer made of the Ni alloy disclosed in Patent Document 1 described above is wet-etched, it is made of the Ni alloy within the substrate surface. It has been confirmed that there is a new problem that the etching of the coating layer becomes uneven, unevenness is likely to occur, and the wiring width varies.
In addition, in the Ni—Cu-based alloys proposed in Patent Document 2 and Patent Document 3, when the amount of Cu added is increased in order to improve the etching property, the oxidation resistance decreases, and the glass substrate and the resin It was confirmed that the adhesion with the film substrate such as ITO or the transparent conductive film was lowered and the oxidation resistance was greatly lowered.

  The object of the present invention is to ensure adhesion with a low-resistance Cu thin film layer, weather resistance, and oxidation resistance, and to stably form a new coating layer that enables stable wet etching. Another object is to provide a sputtering target material for forming a coating layer and a method for producing the same.

  In view of the above problems, the present inventor has intensively studied a sputtering target material for forming a coating layer on a Cu thin film layer. As a result, by adding a specific amount of a specific element to Ni, it has been found that a novel coating layer in which unevenness is hardly generated during etching can be formed while ensuring adhesion, weather resistance, and oxidation resistance, and the present invention has been achieved. did.

That is, the present invention provides a sputtering target material for forming a coating layer of a thin film layer made of Cu or a Cu alloy, containing 5 to 25 atomic% of Mn, and one or more selected from Mn, Mo, Cu and Fe It is a sputtering target material for forming a coating layer containing a total of 60 atomic% or less of the elements, the balance being made of Ni and inevitable impurities, and having a Curie point of room temperature or lower.
In the sputtering target material for forming a coating layer of the present invention, the Mn is 5 to 25 atomic%, the Mo is 5 to 40 atomic%, and the total amount of the Mn and Mo is 15 to 50 atomic%. preferable.
In the sputtering target material for forming a coating layer of the present invention, the Mn is 5 to 25 atomic%, the Mo is 5 to 30 atomic%, the Cu is 10 to 40 atomic%, and the Fe is 0 to 5 atomic%. Preferably there is.
Furthermore, in the sputtering target material for forming a coating layer of the present invention, the Mn is 7 to 20 atomic%, the Mo is 10 to 25 atomic%, the Cu is 10 to 25 atomic%, the Fe is 0 to 3 atomic%, And it is preferable that the total amount of said Mn, said Mo, said Cu, and said Fe is 27-50 atomic% or less.

Further, the present invention is a method for producing a sputtering target material for forming a coating layer of a thin film layer made of Cu or a Cu alloy, containing 5 to 25 atomic% of Mn, selected from the Mn, Cu, Mo, and Fe It can be obtained by pressure-sintering alloy powder having a total of 60 atomic% or less and the balance of Ni and inevitable impurities and having a Curie point of room temperature or lower.
In the present invention, the alloy powder preferably contains 5 to 25 atomic% of Mn, 5 to 40 atomic% of Mo, and 15 to 50 atomic% of the total amount of Mn and Mo.
Moreover, it is preferable that the said alloy powder is 5-25 atomic% of said Mn, 5-30 atomic% of said Mo, 10-40 atomic% of said Cu, and 0-5 atomic% of said Fe.
Further, the alloy powder has the Mn of 7 to 20 atomic%, the Mo of 10 to 30 atomic%, the Cu of 10 to 25 atomic%, the Fe of 0 to 3 atomic%, the Mn, the Mo, The total amount of Cu and Fe is preferably 27 to 50 atomic%.

  Since the present invention can stably provide a sputtering target material capable of forming a coating layer in which unevenness is unlikely to occur during wet etching while ensuring adhesion, weather resistance, and oxidation resistance with a Cu thin film layer, manufacturing of electronic components This is a useful technique for improving the reliability of the obtained electronic components.

It is an example of the photograph which observed the cross-sectional microstructure of the sputtering target material for coating layer formation of this invention with the optical microscope.

The present invention is a sputtering target material for forming a coating layer used for forming a coating layer that covers a Cu thin film layer, containing 5 to 25 atomic% of Mn, and selected from the above Mn, Mo, Cu, and Fe One or more elements are contained in a total amount of 60 atomic% or less, the balance is made of Ni and inevitable impurities, and the Curie point is normal temperature or lower.
Ni is an element that is superior in adhesion to a substrate, a Cu thin film layer, or a transparent conductive film, and also in weather resistance, as compared with Cu, and is formed using the sputtering target material for forming a coating layer of the present invention. Even in the coated layer, it is possible to obtain an effect of improving adhesion and weather resistance by coating a thin film layer made of Cu or Cu alloy.

  In the present invention, Mn, Mo, Cu and Fe added to Ni are both elements that have an effect of improving the etching property for an etchant for a laminated wiring film composed of a thin film layer and a coating layer made of Cu or Cu alloy. It is. The improvement effect is the highest in Mn, followed by Fe, Cu, and Mo. This improvement effect can be improved when the total amount of these additive elements is 15 atomic% or more. However, when the total amount of addition exceeds 60 atomic%, the weather resistance inherent to Ni is greatly reduced. For this reason, the sum total of these additive elements shall be 60 atomic% or less.

  The sputtering target material for coating layer formation of this invention makes a Curie point below normal temperature. As described above, Ni is a magnetic material. In the present invention, in order to perform efficient and stable sputtering, it is necessary to make the nonmagnetic, that is, the Curie point, or less at room temperature at which the sputtering target material is used. In the present invention, “Curie point is below room temperature” means zero when saturation magnetization is measured at room temperature (25 ° C.).

When Mn is added to Ni, the Curie point is lowered to about 15 atomic%, which is a region where Mn is dissolved. On the other hand, if the amount of Mn added to Ni exceeds about 20 atomic%, the Curie point increases, and if it exceeds 25 atomic%, a compound phase appears due to phase transformation, and the Curie point becomes higher than that of pure Ni. The problem that the sputtering target material becomes brittle and it becomes difficult to perform stable processing becomes significant. In addition, the Curie point cannot be lowered to room temperature or less simply by adding Mn, and it is necessary to reduce the thickness of the sputtering target material in order to perform stable sputtering, and there is a problem that the production efficiency is lowered. For this reason, in this invention, in order to make Curie point below room temperature, it adds in combination with the other element effective in demagnetization.
In addition, Mn is an element that is more easily oxidized than Ni, and when Mn is added to Ni by 5 atomic% or more, it is easy to form an oxide at the interface of the film with respect to the substrate, Cu thin film layer, or transparent conductive film. While having the effect of further improving the properties, the oxidation resistance may be lowered if it exceeds 25 atomic%. For this reason, in this invention, the addition amount of Mn shall be 5-25 atomic%. Preferably, the amount of Mn added is 7 to 20 atomic%.

  When Cu is added to Ni, the Curie point is lowered. On the other hand, when the laminated wiring film coated with the Cu thin film layer is heated, the oxidation resistance is lowered and the thin film layer made of Cu or Cu alloy is protected. In addition, the electrical resistance value is likely to increase and the adhesion to the substrate, the Cu thin film layer, the transparent conductive film, or the like decreases. For this reason, in this invention, it is preferable that the addition amount of Cu shall be 10-40 atomic%. More preferably, it is 10 to 25 atomic%.

The effect of lowering the Curie point of Ni, which is a magnetic substance, is the highest for Mo, which is a nonmagnetic element, and when Mo is added to Ni by about 8 atomic%, the Curie point becomes below room temperature. In addition, Ni dissolves Mo at about 30 atomic% in the high temperature range, and the solid solution amount decreases in the low temperature range. If the amount of Mo exceeds 30 atomic%, a compound phase appears, and if it exceeds about 40 atomic%, the compound phase increases and the sputtering target material becomes brittle, making it difficult to perform stable machining.
In addition, increasing the amount of addition of Mo, which has a high demagnetization effect, has the effect of improving the adhesion to the substrate, Cu thin film layer, or transparent conductive film, but the weather resistance tends to decrease, Etching unevenness is likely to occur when etching is performed with a Cu etchant. For this reason, in this invention, it is preferable to make the addition amount of Mo into 5-40 atomic%. More preferably, it is 5-30 atomic%, More preferably, it is the range of 10-25 atomic%.

  Mn and Fe have a high effect of improving etching properties. However, when Fe, which is a magnetic substance, is added to Ni, the Curie point is greatly increased. Further, Fe has a small solid solution region with Cu and easily expresses a compound with Mo. If it is added too much, it causes embrittlement of the sputtering target material. For this reason, in this invention, it is preferable to add Fe in the range with which sputtering target material satisfy | fills nonmagnetic and etching property, and does not embrittle, The addition amount is 5 atomic% or less. More preferably, it is 3 atomic% or less.

From the above, the coating of the present invention that can stably sputter a coating layer that provides the adhesion, weather resistance, oxidation resistance and etching properties required for the coating layer of the Cu thin film layer, and has a Curie point of room temperature or lower In the sputtering target material for layer formation, Mn added to Ni is 5 to 25 atomic%, and the total amount of Mn and one or more elements selected from Mo, Cu and Fe is 60 atomic% or less.
In addition, as the type and amount of the additive element to Ni increase, the amount of compound phase in the sputtering target material increases, and machining for producing a large sputtering target material required for FPD applications Cracking is likely to occur during bonding. For this reason, in this invention, it is preferable that Mn is 5-25 atomic%, Mo is 5-40 atomic%, and the total amount of Mn and Mo is 15-50 atomic%.
Moreover, it is preferable that Mn is 5 to 25 atomic%, Mo is 5 to 30 atomic%, Cu is 10 to 40 atomic%, and Fe is 0 to 5 atomic%.
Moreover, 7-20 atomic% of Mn, 10-25 atomic% of Mo, 10-25 atomic% of Cu, 0-3 atomic% of Fe, and the total amount of Mn, Mo, Cu, and Fe are The range is preferably 27 to 50 atomic%.

Next, the manufacturing method of the sputtering target material for coating layer formation of this invention is demonstrated.
An important feature in the method for producing a sputtering target material for forming a coating layer of the present invention is that an element to be added to Ni that is a magnetic material is selected, and an alloy powder having a Curie point below room temperature is pressure sintered. . The reason for this is that, as described above, Ni is a magnetic material, and when the amount of Ni increases, a Ni ferromagnetic phase that is easily magnetized remains in the sputtering target material, and is generally used in the manufacture of FPDs. This is because in sputtering, the sputtering rate may be reduced and the life of the sputtering target material may be shortened.
Conventionally, an ingot produced by melting a raw material adjusted to a predetermined composition has been subjected to plastic working to form a plate and machined to produce a sputtering target material. On the other hand, the present invention has a specific composition in order to stably produce a large-sized sputtering target material for FPD because the amount of Mn and Mo added is large and the plastic workability is reduced as described above. A manufacturing method in which an alloy powder having a pressure is sintered is most preferable.
In the present invention, the alloy powder contains 5 to 25 atomic% of Mn, contains 60 M% or less in total of the Mn and one or more elements selected from Mo, Cu and Fe, and the balance is An alloy powder consisting of Ni and inevitable impurities and having a Curie point of room temperature or lower is used.
In the present invention, the alloy powder is an alloy powder in which Mn is 5 to 25 atomic%, Mo is 5 to 40 atomic%, the total amount of Mn and Mo is 15 to 50 atomic%, and the balance is Ni and inevitable impurities. Is preferably used.
The alloy powder contains 5 to 25 atomic% of Mn, 5 to 30 atomic% of Mo, 10 to 40 atomic% of Cu, and 0 to 5 atomic% of Fe, with the balance being Ni and inevitable impurities. It is preferable to become.
Further, the alloy powder contains 7 to 20 atomic% of Mn, 10 to 30 atomic% of Mo, 10 to 25 atomic% of Cu, and 0 to 3 atomic% of Fe, with the balance being Ni and inevitable impurities. And the total amount of Mn, Mo, Cu and Fe is preferably 27 to 50 atomic%.

An alloy powder having a Curie point of room temperature or lower can be easily obtained by an atomizing method using an alloy adjusted to a final composition. It is also possible to pulverize the melted ingot to produce an alloy powder. In addition, a method of producing various alloy powders and mixing them to obtain a final composition can also be applied.
Moreover, the impurity in the sputtering target material obtained as the average particle diameter of alloy powder is less than 5 micrometers will increase. On the other hand, when the average particle size of the alloy powder exceeds 300 μm, it becomes difficult to obtain a high-density sintered body. Therefore, the average particle size of the alloy powder is preferably 5 to 300 μm.
In addition, the average particle diameter as used in the field of this invention is represented by D50 of cumulative particle size distribution using the spherical equivalent diameter by the light-scattering method using a laser beam prescribed | regulated by JISZ8901.

  As the pressure sintering used in the method for producing the sputtering target material for forming a coating layer of the present invention, a hot isostatic press (hereinafter referred to as “HIP”) or a hot press can be applied. It is preferable to carry out under conditions of 200 MPa and 1 to 10 hours. The selection of these conditions depends on the pressure sintering apparatus. For example, HIP is easy to apply conditions of low temperature and high pressure, and hot press is easy to apply conditions of high temperature and low pressure. In the production method of the present invention, it is preferable to use a hot isostatic press that can be sintered at a low temperature to suppress the diffusion of the alloy and can be sintered at a high pressure to obtain a high-density sintered body.

If the sintering temperature is less than 800 ° C., the sintering is difficult to proceed and it is difficult to obtain a high-density sintered body. On the other hand, when the sintering temperature exceeds 1250 ° C., a liquid phase appears or crystal growth of the sintered body becomes remarkable, making it difficult to obtain a uniform and fine structure. By sintering in the range of 800 to 1250 ° C., a high-density coating target forming sputtering target material can be easily obtained.
Moreover, if the applied pressure at the time of sintering is less than 10 MPa, sintering does not proceed easily and a high-density sintered body cannot be obtained. On the other hand, if the pressure exceeds 200 MPa, there is a problem that the devices that can withstand are limited.
Further, if the sintering time is less than 1 hour, it is difficult to sufficiently advance the sintering, and it is difficult to obtain a high-density sintered body. On the other hand, sintering time exceeding 10 hours is better avoided from the viewpoint of production efficiency.
When performing pressure sintering with HIP or hot press, it is desirable to deaerate under reduced pressure while heating after filling the alloy powder into a pressure vessel or a pressure die. The vacuum degassing is desirably performed under a reduced pressure lower than the atmospheric pressure (101.3 kPa) in the heating temperature range of 100 to 600 ° C. This is because oxygen in the obtained sintered body can be further reduced, and a high-purity sputtering target material for forming a coating layer can be obtained.

  Moreover, it is preferable that the sputtering target material for coating layer formation of this invention has few elements other than Ni and Mn of a main component, Cu, Mo, and Fe as much as possible. When there are many impurities other than the main component, the electrical resistance value of the obtained multilayer wiring film may increase, or the characteristics such as adhesion and weather resistance may be deteriorated by reacting with other multilayer thin films depending on the kind of element. In particular, oxygen and nitrogen as gas components are easily taken into the thin film, thereby reducing adhesion and causing defects in the thin film. Accordingly, the sputtering target material for forming a coating layer according to the present invention has a purity of 99.9% by mass or more, and impurities such as oxygen are preferably 1000 ppm by mass or less, and more preferably 300 ppm by mass or less.

In order to prepare a sputtering target material for forming a coating layer in which the balance of 10% Mn-25% Cu-10% Mo-3% Fe consists of Ni and unavoidable impurities in atomic ratio, first, the purity of the above composition is 99.9. % Alloy powder having an average particle diameter of 65 μm was prepared by a gas atomization method.
When the obtained alloy powder was brought close to the SmCo magnet, it was confirmed that it did not adhere to the magnet. Moreover, when the obtained alloy powder was put in a powder case for measuring magnetic properties and the magnetic properties were measured at room temperature (25 ° C.) using a vibrating sample magnetometer VSM-5 manufactured by Riken Denshi Co., Ltd., It was confirmed to be non-magnetic.

Next, the alloy powder obtained above was filled in a mild steel container having an inner diameter of 133 mm, a height of 30 mm, and a thickness of 3 mm, and heated at 450 ° C. for 10 hours for degassing treatment. Sealed and sintered by a HIP apparatus at 1000 ° C., 148 MPa for 5 hours.
After cooling this mild steel container, it was taken out from the HIP device, and the mild steel container was removed by machining to obtain a coating target forming sputtering target material having a diameter of 100 mm and a thickness of 5 mm. Moreover, the test piece was cut out from the remainder.

The relative density of the obtained test piece was measured by the Archimedes method. The relative density as used in the present invention is a bulk density measured by Archimedes method, obtained as a weighted average of elemental elements calculated by a mass ratio obtained from the composition ratio of the sputtering target material for coating layer formation of the present invention. The value obtained by multiplying the value divided by the theoretical density by 100.
As a result, it was confirmed that the relative density was 99.9%. According to the production method of the present invention, it was confirmed that a high-density coating target forming sputtering target material can be obtained.

  Next, quantitative analysis of the metal element of the obtained test piece is performed with an inductively coupled plasma emission spectrometer (ICP) (model number: ICPV-1017) manufactured by Shimadzu Corporation, and non-dispersive infrared absorption is determined for oxygen. When measured by the method, the total purity of the analysis values of Ni, Mn, Cu, Mo, and Fe is 99.9% and the oxygen concentration is 500 ppm by mass. According to the manufacturing method of the present invention, high purity coating It was confirmed that a sputtering target material for layer formation was obtained.

  The test piece obtained above is mirror-polished, then corroded with a Nital reagent, and the result of observing the structure with an optical microscope is shown in FIG. As shown in FIG. 1, the sputtering target material for forming a coating layer of the present invention has a fine recrystallized structure in a spherical alloy powder obtained by a gas atomization method, and the average crystal grain size is 35 μm. there were. In addition, the sputtering target material for forming a coating layer according to the present invention was confirmed to be a sputtering target material suitable for sputtering film formation without confirming large defects such as segregation and vacancies.

  Next, the sputtering target material for forming the coating layer obtained above is brazed to a copper backing plate, and then attached to a sputtering apparatus (model number: CS-200) manufactured by ULVAC, Inc., Ar atmosphere, pressure 0.5 Pa The sputtering test was conducted under the condition of power of 500W. It was confirmed that when sputtering was performed using the coating layer forming sputtering target of the present invention, stable sputtering could be performed without abnormal discharge.

Next, a Cu sputtering target material cut out from an oxygen-free copper plate material manufactured by Hitachi Cable, Ltd. (currently Hitachi Metals, Ltd.) and a sputtering target material for forming a coating layer of the present invention prepared in Example 1 were used. Using a 25 mm × 50 mm glass substrate (product number: EagleXG) manufactured by Corning, under the same sputtering conditions as in Example 1, a coating layer having a thickness of 50 nm, a Cu thin film layer having a thickness of 200 nm on the glass substrate, A sample of a laminated wiring film in which a coating layer having a thickness of 50 nm was sequentially formed was prepared, and moisture resistance and heat resistance were evaluated as adhesion and weather resistance.
The evaluation of adhesion was performed by the method defined in JIS K 5400. First, a transparent adhesive tape (product name: transparent beautiful color) manufactured by Sumitomo 3M Co., Ltd. is applied to the surface of the coating layer formed above, and a square of 2 mm square is put with a cutter knife, and the transparent adhesive tape is peeled off. Evaluation was made based on whether or not the coating layer remained. It was confirmed that the coating layer formed using the sputtering target material for forming a coating layer according to the present invention did not peel off even a single layer and had high adhesion.

  For the evaluation of moisture resistance, the sample prepared above was left in an atmosphere of 85 ° C. and 85% humidity for 300 hours, and the presence or absence of discoloration on the surface of the coating layer was visually confirmed. It was confirmed that the coating layer formed using the sputtering target material for forming a coating layer of the present invention did not change color even when exposed to a high-temperature and high-humidity atmosphere and had high moisture resistance.

  In the evaluation of heat resistance, the sample prepared above was heated in an atmosphere of 350 ° C. in the atmosphere for 30 minutes, and the presence or absence of discoloration on the surface of the coating layer was visually confirmed. It was confirmed that the coating layer formed using the sputtering target material for forming a coating layer of the present invention did not change color even when heated at a high temperature and was a coating layer having high heat resistance.

First, the sputtering target material for coating layer formation of the present invention produced in Example 1 and the Cu sputtering target material produced in Example 2 were prepared. As a comparison, ingots of respective alloys having atomic ratios of Ni-18% Mo and Ni-30% Cu-3% Ti are cast by vacuum melting, and sputtering with a diameter of 100 mm and a thickness of 5 mm is performed by machining. A target material was produced. Next, each sputtering target material was brazed to a copper backing plate and attached to the same sputtering apparatus as in Example 2. And the sample for etching evaluation which formed the coating layer of thickness 100nm on the same conditions as Example 2 on the glass substrate (product number: EagleXG) made from Corning by 25 mm x 50 mm was obtained.
Further, on the 25 mm × 50 mm glass substrate (product number: EagleXG) manufactured by Corning under the same sputtering conditions as in Example 1, using the sputtering target material for forming a coating layer of the present invention and the Cu sputtering target material prepared above. A sample for etching evaluation comprising a laminated wiring film in which a coating layer having a thickness of 50 nm, a Cu thin film layer having a thickness of 200 nm, and a coating layer having a thickness of 50 nm were sequentially formed was also prepared.

Each sample obtained above is etched by immersing in CU-02 manufactured by Kanto Chemical Co., Ltd., which is an etchant of Cu, and visually observed until the coating layer on the glass substrate is completely transparent, and the time is measured. At the same time, unevenness during etching was also confirmed.
As a result, Cu was uniformly etched in about 25 seconds in the 100 nm single layer film sample. On the other hand, the coating layer made of a Ni-18 atomic% Mo alloy required 90 seconds for completion of etching, and it was confirmed that unevenness was generated by etching in an island shape at an early etching portion and a late etching portion.
In addition, it is confirmed that the coating layer made of a Ni-30 atomic% Cu-3 atomic% Ti alloy requires 100 seconds to complete the etching, and the early etching portion and the slow etching portion are etched in stripes. It was done.
On the other hand, it was confirmed that the coating layer formed with the sputtering target material for forming a coating layer of the present invention was uniformly etched in about 40 seconds.
In addition, the etching evaluation sample in which the laminated wiring film is formed by using the coating layer forming sputtering target material of the present invention takes about 90 seconds to complete the etching and can be uniformly etched without unevenness. Met.
From the above, the coating layer formed with the sputtering target material for forming a coating layer of the present invention can be etched uniformly at a narrow pitch using a Cu etchant even when it is laminated with a Cu thin film layer. It can be estimated that there is.

  In order to produce a sputtering target material having the composition shown in Table 1, Ni, Mn, Cu, and Mo raw materials having a purity of 3N or more are prepared, weighed so as to have a predetermined composition, and melt casting in a vacuum melting furnace. An ingot was prepared. The adhesion of the produced ingot to the magnet, machinability and sputter discharge were evaluated. In addition, the evaluation of the machinability of the sputtering target material is as follows: ◯ if there was no crack generation and good cutting, △ if cracking occurred during machining, △ cracking before machining It evaluated as x. In addition, the sputter discharge property was evaluated as “Good” when there was no abnormal discharge and sputtering was good. The results are shown in Table 1.

When the SmCo magnet was brought close to the ingot, the sample No. 3 was confirmed to be a magnetic substance because it adhered to the magnet. On the other hand, samples made of other alloys were confirmed to be nonmagnetic without adhering to the SmCo magnet.
Sample No. 2 and Sample No. In No. 4, cracking occurred when the ingot was taken out from the ingot case. And sample no. 2 discontinued further evaluation.
Using each of the above ingots, an alloy powder was produced by the atomizing method in the same manner as in Example 1, and a sintered body was produced by HIP. Each of the sintered bodies was cut with a wire cut and an attempt was made to produce a sputtering target material having a diameter of 100 mm and a thickness of 5 mm. 3 and sample no. No. 10 cracked during processing. Sample No. No. 4 could not produce a sputtering target due to cracking.
Next, sample No. 1, sample no. 3, Sample No. 5-No. Ten sputtering target materials were brazed to a copper backing plate. Then, it attached to the sputtering apparatus (model number: CS-200) by ULVAC, Inc., and performed the sputter test on conditions of Ar atmosphere, pressure 0.5Pa, and electric power 500W.
It was confirmed that when sputtering was performed using the coating layer forming sputtering target of the present invention, stable sputtering could be performed without abnormal discharge.

After the discharge test performed in Example 4, a coating layer having a thickness shown in Table 2 was formed on a 25 mm × 50 mm glass substrate to prepare a sample for etching evaluation. Evaluation of etching property was performed using Cu etchant (CU-02) manufactured by Kanto Chemical Co., Ltd. as in Example 3. In order to form a coating layer with a small amount of side etching, it is necessary to suppress unevenness in etching time, reduce overetching time, and moderately suppress wettability to an etchant.
Etching unevenness was visually confirmed as in Example 3. In order to obtain a clearer difference, each sample was immersed in an etchant solution, and a time difference between a time during which part of the film permeated and a just etching time during which the entire surface permeated was measured. This means that the smaller the time difference, the less the etching unevenness. Further, 20 μl of an etchant was dropped on the film surface, and the spread diameter after 2 minutes was measured. This means that the smaller the spread diameter is, the more the side etching can be suppressed, and the more accurate etching can be performed. The evaluation results are shown in Table 2.

  As shown in Table 2, the coating layer formed of the sputtering target material for forming a coating layer containing an appropriate amount of Mn of the present invention has a small time difference between the start and end of permeation during etching, and the spread diameter of the etchant is also small. It was confirmed that it is possible to perform highly accurate etching that is almost the same as Cu, with less etching unevenness and side etching.

Next, in the same manner as in Example 2, a sample of a laminated wiring film in which a coating layer having a thickness of 50 nm, a Cu thin film layer having a thickness of 300 nm, and a coating layer having a thickness of 50 nm were sequentially formed on a glass substrate was prepared. . And the adhesiveness and oxidation resistance of each sample were evaluated. Evaluation of adhesion was performed in the same manner as in Example 2. Then, the case where none of the coating layer was peeled off was evaluated as “◯”, the case where the covering layer was peeled off was evaluated as “Δ”, and the case where the covering layer was peeled off was evaluated as “x”.
In addition, the oxidation resistance was evaluated by subjecting each sample to a heat treatment at a temperature of 200 ° C. to 300 ° C. for 30 minutes in an air atmosphere, and measuring the reflectance. The reflectance was a spectrocolorimeter (model number: CM2500d) manufactured by Konica Minolta, Inc. The evaluation results are shown in Table 3.

As shown in Table 3, Sample No. 1 and sample no. No. 11 had low adhesion. Sample No. 5 showed that the adhesion was improved by containing 4% of Mn, but it was still not sufficient.
On the other hand, it was confirmed that the adhesion of the laminated film in which the coating film was formed using the coating layer forming sputtering target material of the present invention was greatly improved.
Sample No. In No. 1, the reflectance decreased greatly at high temperatures, and the oxidation resistance was low.
In contrast, a laminated film in which a coating film is formed using a sputtering target material for forming a coating layer suppresses a decrease in reflectance even when heated to a high temperature of 350 ° C., and provides sufficient oxidation resistance. It was confirmed that

  Next, evaluation of moisture resistance, which is one of weather resistance, was performed using the sample manufactured in Example 6. The evaluation method of moisture resistance was performed in the same manner as in Example 2, and the reflectance was measured in the same manner as in Example 6. The evaluation results are shown in Table 4.

As shown in Table 4, the laminated film in which the coating layer was formed using the sputtering target material for coating layer formation of the present invention has little decrease in reflectance due to discoloration even if left in a high temperature and high humidity atmosphere for a long time, It was confirmed that sufficient moisture resistance was obtained.
From the above, by using the sputtering target material for forming a coating layer according to the present invention, the adhesion, weather resistance, and oxidation resistance of the Cu thin film layer are secured, and a coating layer capable of stable wet etching is stably formed. It was confirmed that it was possible.

Claims (4)

In a sputtering target material for forming a coating layer of a thin film layer made of Cu or Cu alloy, Mn is contained in 7 to 25 atomic% , Mo is contained in 5 to 30 atomic%, Cu is contained in 10 to 40 atomic%, and Fe is contained in 0 to 5 atomic%. And the total amount of Mn , Mo, Cu, and Fe is 60 atomic% or less, the balance is Ni and inevitable impurities, and the Curie point is room temperature or lower. Target material.   The Mn is 7 to 20 atomic%, the Mo is 10 to 25 atomic%, the Cu is 10 to 25 atomic%, the Fe is 0 to 3 atomic%, and the Mn, Mo, Cu, and Fe The total amount is 27-50 atomic%, The sputtering target material for coating layer formation of Claim 1 characterized by the above-mentioned. The method of manufacturing a Cu or Cu of an alloy thin layer for forming a coating layer sputtering target material, Mn and 7-25 atomic%, Mo 5 to 30 atomic%, Cu is 10 to 40 atomic%, Fe 0 to 5 Atomic% contains , Mn , Mo, Cu, and Fe in total contain 60 atomic% or less, the remainder is made of Ni and inevitable impurities, and the alloy powder having a Curie point below room temperature is pressure sintered. The manufacturing method of the sputtering target material for coating layer formation characterized by the above-mentioned. In the alloy powder, the Mn is 7 to 20 atomic%, the Mo is 10 to 30 atomic%, the Cu is 10 to 25 atomic%, the Fe is 0 to 3 atomic%, the Mn, the Mo, and the The total amount of Cu and said Fe is 27-50 atomic%, The manufacturing method of the sputtering target material for coating layer formation of Claim 3 characterized by the above-mentioned.