JP2605593B2 - Cu-based conductor alloy material, etching method thereof, and magnetic head using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film magnetic head used for a magnetic disk or a VTR, a magnetoresistive head, a magnetic sensor used for a rotation angle center, etc., or a flat type transistor transducer, a printed circuit board, a semiconductor device, etc. C used as a thin film conductor pattern
u-based thin film conductor alloy material, its etching method, and C
The present invention relates to a magnetic thin film device using a u-based thin film conductor alloy material.

[0002]

2. Description of the Related Art In a device using a magnetic thin film such as a thin film magnetic head and a magnetoresistive element, thin film conductor patterns of various shapes and configurations are used. Metals are mainly used as materials for forming the thin film conductor pattern, and Cu and its alloys, Au, Al and its alloys, P
Typical examples include t, W, and alloys thereof. C in these
Materials other than u are used for thin film fine wiring and electrodes for semiconductor devices. Compared to these materials, Cu and its alloys are initially less expensive and more resource-rich than Au, Pt, W and its alloys. In addition, a product having a higher purity than Al and its alloys can be easily obtained at low cost, is excellent in ductility and malleability, and is excellent as a conductive wire.

[0003] On the other hand, as a Cu alloy material, as disclosed in the Japan Institute of Metals, Metal Data Book, 1974, p. Things have been devised. These are bulk alloy materials that have been designed to maximize surface properties such as strength, toughness, and conductivity. However, bulk alloy materials have become alloy designs that require relatively large-scale metallographic material modification, such as long-range diffusion of alloy components in the Cu matrix due to heat treatment and precipitation of the second phase. Therefore, when the diffusion distance of the added alloy component cannot be secured or the heat treatment temperature cannot be freely set due to the device configuration, as in the case of a thin film conductor alloy material, it is not possible to obtain various characteristics by thinning the bulk material as it is. Impossible. Prior to that, the basic required characteristics are different from the emphasis on the fact that the thin film conductor alloy material of the present invention can be easily etched.

As a thin film material, pure Cu formed by a frame plating method on a thin film magnetic head, a printed circuit board or the like has been widely used. As a thin film conductor alloy material containing Cu, as disclosed in Japanese Patent Application Laid-Open No. 64-53548, an alloy containing a small amount of Cu in Al,
Alloys containing trace amounts of i and Cu are widely used as wiring materials for semiconductor devices. However, the alloy material is C
This is a composition range (an alloy containing 4 wt% or less of Cu) which should be almost called an Al alloy rather than a u alloy.

On the other hand, as a method for producing a fine pattern of a Cu-based thin film conductor material, Ohno et al.
There is one disclosed in IEICE Technical Report, [Silicon Materials and Devices], SDM90-182, 1990, page 37. In the known document, a desired resist pattern is formed on a pure Cu film on a substrate, the resist pattern is hard baked, and then a substrate temperature of 280 is obtained.
° C., N ₂ -SiCl ₄ gas mixture, the gas pressure 2 Pa, under the conditions of input power _{200W, SiCl 4, N 2,} Cl 2, and subjected to reactive ion etching using a mixed gas of NH _3, with the resist pattern The Cu film other than the portion covered is removed by etching, and the desired pure Cu
A thin film conductor pattern is formed.

Further, as an example of a device that generally uses a Cu-based thin film conductor material, a method for producing a coiled thin film conductor pattern using pure Cu for generating a magnetic field / induced current in a thin film magnetic head is described. Kazhiko Yamada et al., Journal of Applied Physics, Vol. 55, No. 6, 1984, p. 2235. According to this, the thin film magnetic head has a form in which a lower magnetic material pattern, an insulating film, a thin film conductor coil pattern, an insulating film, an upper magnetic material pattern, and a protective film are sequentially stacked on a substrate. Here, a nonmagnetic oxide ceramic material is used as the substrate, and Ni-F is used as the upper and lower magnetic material patterns.
e alloy, aluminum oxide as an insulating film and a protective film,
Silicon oxide, baked photoresist and the like are widely used. Further, in particular, a method of manufacturing the thin film conductor pattern is disclosed in detail, for example, in Kazuhiko Yamada et al., Proceedings of the 1983 IEEJ General Conference, page 1-186. Here, the above-described frame plating method is used. This is a technique in which a resist pattern having an inverted shape of a desired pattern is first formed, and Cu is buried in a void portion (having a desired pattern shape) by a plating method.

Finally, in a conventional magnetoresistive head, pure Cu or A by sputtering or vacuum evaporation is used.
u is used. As disclosed in Hayama, Japanese Utility Model Publication No. 2-6491, Japanese Unexamined Patent Publication No. 2-6491, the conventional magnetoresistive head has a soft magnetic film on a substrate made of an Al ₂ O ₃ —TiC sintered body with an alumina film. A multilayer film pattern of a magnetoresistive element (MR element) including a magnetic shield, an insulating film, a magnetoresistive film, and the like is formed, and pure Cu or Au is formed thereon.
After forming a thin-film conductor pattern according to (1), an insulating film and a magnetic shield are formed again. An argon ion milling method using a photoresist as a mask is used for manufacturing the thin film conductor pattern.

[0008]

As shown in the prior art, as a thin film conductor alloy material containing Cu, Al, which is widely used as a wiring material for semiconductor devices, is used.
Alloys containing trace amounts of Cu and Al containing trace amounts of Si and Cu are most known. However, as described above, the alloy material has a composition range that should be called an Al alloy rather than a Cu alloy (Cu is at most 4 wt%, and in practice, an alloy of 0.5 wt% or less is generally used) More importantly, it has been found that such alloys are problematic in terms of migration resistance. Migration is a phenomenon in which atoms constituting a conductive material self-diffuse when a current is applied to a thin-film conductor pattern, causing breakage in a wiring pattern. A document on electromigration in semiconductor integrated circuits, edited by Reliability Center for Electronic Components of Japan A survey report was disclosed in detail in 1987. The use of a material system that causes migration is a major problem in the long-term reliability of a product using the device. This is similar to a magnetoresistive head,
This is particularly remarkable in the case of a device that must be driven at a high current density (1 × 10 ⁶ A / cm ² or more),
Use of an i-Cu alloy is not preferred. To solve this problem, a material system having a high Cu composition is advantageous. Therefore, the current magnetoresistive head and thin film magnetic head use the pure Cu thin film conductor pattern formed by the frame plating method described above. However, even in the Al-Si-Cu alloy system,
According to the study of the present inventors, the Cu composition was about 2.6 at% (about 6 at%).
(% by weight) or more, the migration resistance was sharply improved. Incidentally, the Cu-based thin film conductor alloy material of the present invention,
Since a higher concentration Cu region is used, the resistance to such migration is sufficient.

The Cu-based thin film conductor alloy material of the present invention
The greatest feature is that it is a material that can perform reactive ion etching, which is general as a microfabrication technology, at a low temperature. In a conventional thin film conductor pattern forming process by reactive ion etching of a Cu thin film, the sample temperature is raised to about 280 ° C. as described in the previous section, so that peeling of the hard baked and carbonized resist from the Cu pattern does not occur. The problem of becoming possible is inevitable.
In semiconductor devices, in order to take advantage of the easiness of microfabrication processes using ordinary resist patterns that are easy to peel off,
The use of a material containing Cu as a main component as a conductor wiring material has not been performed so far, and Al—Si—
Dry etching is performed at a low temperature using a Cu alloy. Further, since the carbonized resist contains chlorine as an etching gas component adsorbed during the reactive ion etching, corrosion of the Cu pattern is likely to occur due to the reaction with moisture in the atmosphere after the production of the conductive thin film pattern, Use of a material and a manufacturing method that cannot remove such a resist has a problem in long-term reliability of a product.

Furthermore, the etching process at 280 ° C. can be said to have no problem if the hard-baked resist can be stripped, if the semiconductor device is made of a relatively heat-resistant material. In the case of (1), a soft magnetic material (for example, an artificial lattice material having a multilayer structure of Fe / NiFe or a Co-based amorphous material) that is not suitable for heat treatment to maintain the characteristics is often used as a device component material. 2 as material
It is necessary to use a material that can be dry-etched at a temperature lower than 80 ° C. This problem of maintaining the characteristics of the magnetic material during the manufacturing process is particularly remarkable in the manufacturing process of a magnetoresistive head which requires control of the characteristics of an ultrathin magnetic film having a thickness of 50 nm or more. It can be said that this is a high-temperature treatment that is critical for the production of the resistance effect head.

On the other hand, Miyazaki et al., JP-A-62-265331.
In the method of etching copper or a copper alloy disclosed in Japanese Patent Laid-Open Publication No. H11-27139, the material can be etched using nitrogen, oxygen, or nitrogen oxide, thereby enabling etching at a lower temperature than before. However, according to the study of the present inventor, a Cu thin film having a thickness of 1.5 μm contains oxygen molecules or molecules (such as nitrogen oxides) containing oxygen as a constituent element in an amount of 5% or more in terms of oxygen partial pressure. When etching is performed using a suitable gas system, the generated Cu pattern having a width of 5 μm or less is completely oxidized, and a fine pattern of copper or a copper alloy (available as a conductor) cannot be manufactured. It has been found that a fine pattern of oxides (not usable as conductors) is produced. It is considered that accurate evaluation of the characteristics of the manufactured wiring pattern was not carried out in the above-mentioned known literature, and thus it was considered that the occurrence of oxidation was not apparent. As is generally well known, Cu is very easily oxidized, and Al
It is not an oxidized form in which a non-conductive film is formed on the surface and oxidation does not proceed as described above, but has a characteristic that oxidation easily proceeds further from the surface to the inside. Since the Cu thin film conductor pattern used in the magnetic thin film device of the present invention requires a pattern width of 5 μm or less, which is a problem in the method of the known document, the method of the known document is not suitable as a method of manufacturing a thin film conductor pattern. Absent.

Further, the conventional method of manufacturing a pure Cu thin-film conductor coil pattern for a thin-film magnetic head by a frame plating method has many problems as described below.

It is difficult to form an inverted resist pattern having a high aspect ratio and an inverted trapezoidal cross section.

The resist is easily peeled off in the plating bath.

[0015] Because of the wet process, it is difficult to manufacture while maintaining process continuity.

Since the film formation of another material is a dry process, there is a limit in improving the throughput.

It is difficult and expensive to maintain the quality of the plating bath;

It is almost impossible to make an arbitrary Cu-based alloy.

To address these problems, techniques such as ion milling (ion beam etching) and lift-off are common techniques for manufacturing magnetic thin film devices, but are not optimal as methods for manufacturing fine thin film conductor patterns. Absent. This is because, in these two processes, a resist pattern having a high aspect ratio, which is difficult to manufacture, must be formed as in the case of manufacturing the Cu thin film conductor pattern by plating. The reason for this is that ion milling requires a thick-film resist mask because the selectivity with the mask material is small, and lift-off also requires a thick-film resist pattern to dissolve and remove the photoresist after Cu conductor deposition. Is mentioned. It is clear that a process requiring a resist pattern having such a high aspect ratio cannot meet the demand for miniaturization in the near future. In addition, although ion milling is used in the actual manufacturing process of the magnetoresistive head as described above, overetching is not possible because the etching selectivity with the magnetic film layer, which is the underlying layer of the thin film conductor pattern, cannot be obtained. In such a case, the magnetoresistive element which is a magnetic film layer is etched. This is a major cause of a decrease in yield of wafers in manufacturing the magnetoresistive head. If the ion milling process is cut off early for fear of over-etching, the thin film conductor pattern is often still in a short-circuit state before patterning,
After all, it cannot be used as a magnetic head. In addition, since it is impossible to completely eliminate the ion beam intensity distribution in the wafer surface, there is a problem that what has just been etched and what has been over-etched are mixed in the wafer. The fact is that there are variations in the characteristics.

From the above, although features such as low resistance and high migration resistance of Cu and an alloy containing Cu as a main component are characteristics necessary for a thin film conductor material, a conventional thin film conductor material maintaining such characteristics has been developed. Not only has not been found, but it can be seen that when an alloy containing Cu as a main component is formed into a fine thin film conductor pattern, it cannot be manufactured by a low-temperature dry process.

An object of the present invention is to provide a Cu-based thin film conductor alloy material capable of realizing the following three items, to provide a method for etching the material, and to use the material to manufacture a thin film conductor pattern. Another object of the present invention is to provide a magnetic thin film device such as a magnetic head and a magnetic sensor, which are manufactured without deteriorating the performance of the magnetic thin film and have high long-term reliability. By using this material, the manufacturing process of the thin film conductor pattern by the conventional frame plating method can be simplified by maintaining the continuity of the process by the dry process, reducing the total number of processes from the conventional manufacturing process, and simplifying the apparatus. Reduce costs,
And it enables to manufacture quickly. By using this material, a photoresist that can be easily peeled off after etching and that can simplify the process can be used as an etching mask material when forming a thin film conductor pattern. Enable. By using this material, it is possible to lower the temperature during etching while using an etching gas that does not deteriorate the properties of the conductor material due to oxidation or the like during etching, and to form a fine thin film conductor pattern having a width of 5 μm or less. .

[0022]

The Cu-based thin film conductor alloy material of the present invention is characterized in that B, C, N, Al, Si,
P, S, Ga, Ge, As, Se, In, Sn, Sb,
Te, Bi, Po, Be, Ti, V, Zr, Nb, M
At least one of o, Tc, Hf, Ta, W, Re, Pa, and U is added, and the lower limit (W ⁿ [at%]) of the amount of the additional element is added to each of the additional elements k . quantity and, between the boiling point of the chloride of the additive element ^{(T b k [K])} , equation 1 is satisfied, an appropriate amount of the upper limit of the additive element at the same time, pure Cu and the same crystal structure at least a It is characterized in that an additive element is added in a range having a part.

[0023]

(Equation 1)

The method of etching a Cu-based thin film conductor alloy material of the present invention is characterized in that etching is performed using a gas containing chlorine in a temperature range of 180 ° C. or less.

The thin-film magnetic head of the present invention has a non-magnetic layer forming a gap on a substrate, a spiral conductor on an insulator, and applying a current to the conductor from the outside to generate a magnetic field near the center. In a thin-film magnetic head in which upper and lower magnetic poles made of a soft magnetic film are arranged with a thin-film conductor pattern capable of generating an induced current in a conductor by changing or generating a magnetic field near the center, The thin film conductor pattern is formed of the Cu-based thin film conductor alloy material.

Further, a magnetoresistive head according to the present invention is a magnetoresistive head having at least a magnetoresistive element and a pair of thin-film conductor patterns arranged in contact with the magnetoresistive element, wherein the thin-film conductor pattern is It is characterized by being formed of the Cu-based thin film conductor alloy material.

[0027]

The present inventor made various thin films of a Cu-based alloy, which have not been studied so far, and conducted several experiments. As a result, when Al is added to Cu instead of adding Cu to Al as in the conventional thin film wiring material, there is a correlation between the Al concentration and the temperature at which reactive ion etching is possible. Is as shown in FIG.
A parallel plate type reactive ion etching apparatus was used for etching, the gas was SiCl ₄ at 5 sccm, and the input power was 1
00W. FIG. 1 shows C at various concentrations of 200 nm.
Indicates the lowest temperature at which the u-Al alloy film can be removed by etching for 10 minutes, and the lowest etching temperature for obtaining an effective etching rate from the viewpoint of throughput when using a Cu-based alloy in a manufacturing process. Is shown. According to the study, at a temperature lower than this by 10 ° C. or more, the reaction product with the etching gas is not desorbed while being deposited, and the etching does not proceed. As can be seen from FIG. 1, increasing the amount of added Al can reduce the temperature during etching, and the addition of about 10 at% or more achieves etching at 180 ° C. or less, which enables reactive ion etching using a photoresist as a mask. Was revealed.

Although the tendency of lowering the etching temperature due to such alloying is shown here only for Al,
Other alloying elements of the present invention (B, C, N, S, Ga, G
e, Se, In, Sb, Te, Hg, Bi, Po, B
e, Ti, V, Zr, Nb, Mo, Tc, Hf, Ta,
The same tendency is observed when one or a plurality of (Re, Pa, U) are used, and the reactive ion etching technique using a photoresist mask was also applicable. And as a result of synthesizing experiments on these various additional elements, Cu
(W ⁿ [at%])
If, between the boiling point of the chloride of the additive element ^{(T b k [K])} , was observed is shown by the formula 1.

[0029]

(Equation 1)

Here, the etching temperature is defined as a minimum temperature at which a 200-nm thick Cu-based alloy film having a thickness of 200 nm can be removed by etching for 10 minutes , similarly to the above. This can effect <br/> results against the reduced etching temperature by the addition element species are different, also the degree of the effect has a boiling point and strong correlation of additive element species of chloride, further alloying additions species Indicates that the effect is obtained by adding up when a plurality of types are increased instead of one type. In other words, when adding an additive element having a low boiling point of chloride, the etching temperature sharply decreases with an increase in the added amount,
Whereas the etching ratio at 180 ° C. or less was realized with a relatively small amount of addition, in the case of a material having a high boiling point of chloride, on the other hand, the etching temperature gradually decreased with respect to the added amount. For the first time, etching at 180 ° C. or less was realized. Such a relationship with the boiling point of chloride can be understood from the fact that in the etching reaction, elimination of chloride of the reaction product needs to occur.

Now, such an additive element that is effective in lowering the etching temperature is not something that can be added unnecessarily. Investigations of the present inventor have revealed that the effect of reducing the etching temperature is not observed when the amount of the added element is increased and the alloy structure is formed only of an alloy having a crystal structure different from that of the Cu matrix. . This is shown in FIG.
This corresponds to the fact that the etching temperature is high in the Al composition near the sample, and a crystal structure different from Cu was observed in the sample near 35 at%. In general, alloys having a structure different from these parent phases are called intermetallic compounds, and are described in detail in Masao Doyama, Masaya Yabe, Intermetallic Compounds Data Handbook, Says Forum, Tokyo, 1989. As described above, it has physical properties different from those of the base metal constituting the alloy. In other words, in each of these phases, each constituent atom is in a more chemically stable state than a solid solution in a discrete state with respect to the parent phase. . As a result, it is considered that the chemical reactivity with chlorine was directly affected, and the result that the added element was not effective in reducing the etching temperature was obtained. From the above, the Cu-based thin film conductor alloy material of the present invention needs to include at least a part of the same crystal structure as the Cu matrix in the actual material structure. Also, the same crystal structure as the Cu mother phase is different for each additional element,
The existing composition range changes depending on the method of forming the thin film or the heat treatment process, and the composition range cannot be specified unconditionally. In general, it is known that, in a film forming method involving rapid cooling of atoms such as a sputtering method, a composition range is expanded to a high addition concentration side, and the composition range is narrowed to a low concentration side by performing heat treatment. Actually, it is necessary to directly observe the alloy structure and determine whether or not the Cu matrix can be confirmed. As a guide of the composition range after the heat treatment, M. Hansen, Constitution of Binary Alloys, McGraw-Hill Book Company, New York, 19
In the equilibrium state diagram disclosed in, for example, 1958, it can be roughly determined whether the amount of the added element is within the composition range of the phase including the Cu mother phase. However, this standard is not effective for alloy systems of three or more elements (three kinds of added elements) or thin films before heat treatment.

[0032]

【Example】

(Example 1) Next, in order to show the features of the CU-based thin film conductor alloy material of the present invention, a method of manufacturing a thin film conductor pattern using the material will be described in detail with reference to FIG. (A) First, a Cu-based thin film conductor alloy material 2 of the present invention is formed on a substrate 1. Here, S with thermal oxide film is used as substrate 1.
An i substrate was used. As a method of forming the Cu-based thin film conductor alloy material 2, any method such as a sputtering method, a vacuum deposition method, a metal organic chemical vapor deposition growth method, and an electrolytic / electroless plating method may be used. In this embodiment, a Cu-9.4 at% Al alloy, Cu-4.5 at
% Si alloy, Cu-15at% W alloy, Cu-8at%
As was deposited to a thickness of 1 μm each. (B) Next, a photoresist 3 is applied on the Cu-based thin film conductor alloy material 2 and is patterned into a desired thin film conductor pattern. In this embodiment, AZ manufactured by Shipley Co., Ltd.
A line and space pattern was formed using 1350J. The photoresist 3 has a thickness of 2 μm and a pattern width of 0.5 μm. (C) Subsequently, they are introduced into a reactive ion etching apparatus. The equipment contains SiCl ₄ as chlorine-based gas for 5 seconds.
ccm, 20 sccm of N ₂ and 10 sccm of NH ₃ as a mixed gas, gas pressure 3 Pa, input power 200
Under the conditions of W and a substrate temperature of 180 ° C., high-frequency plasma 4 of 13.56 MHz was generated, and reactive ion etching was performed. (D) Finally, the substrate 1 after etching the Cu-based thin film conductor alloy material 2 is taken out of the etching apparatus,
The photoresist 3 was peeled off using an organic solvent. Substrate 1
As a result of observation with a scanning electron microscope from the fracture surface direction of
All alloys have good rectangularity and both width and thickness are 1.5
A μm thin film conductor pattern 5 was formed. At this time, since the etching gas did not contain oxygen, the pattern was not oxidized by micro Auger analysis. (Embodiment 2) Next, an embodiment of a thin film magnetic head using the Cu type thin film conductor alloy material of the present invention will be described with reference to FIG. (A) On the alumina insulating film 7 formed on the lower magnetic material pattern 6 made of NiFe on the substrate 1 made of the Al ₂ O ₃ —TiC sintered body with the alumina film,
After forming the film 8 to a thickness of 50 nm, the Cu-based thin film conductor alloy material 2 of the present invention is formed. In this embodiment, Cu-25 at% B
e alloy was formed into a film having a thickness of 3 μm. Further, a Cr film 8 was further formed thereon as an adhesion layer to a thickness of 50 nm. All film formation was performed by using a sputtering method. (B) Next, a photoresist 3 is applied on the Cu-based thin film conductor alloy material 2, and this is turned into a desired thin film conductor pattern. In this embodiment, AZ4 manufactured by Shipley Co., Ltd. is used.
620 was used to form a conductor coil-shaped resist pattern. The thickness of the photoresist 3 is 3 μm, and the minimum portion of the pattern width is 2 μm. (C) Subsequently, they are introduced into a reactive ion beam etching apparatus. The device contains SiCl ₄ as chlorine-based gas.
The 3.7sccm, 21.3sc the N ₂ as a mixed gas
cm, NH ₃ is supplied at 5 sccm, the substrate temperature is 160 ° C., and the substrate rotation speed is 12 r. p. Under a condition of m and an acceleration voltage of 800 V, the multilayer film of Cr / Cu / Cr structure was irradiated with an ion beam 9 made of a reactive gas to perform etching. (D) As a final step of pattern formation, the substrate 1 after etching is taken out of the reactive ion beam etching apparatus, and the photoresist 3 is peeled off using an organic solvent. As a result, the substrate 1 has a rectangular shape with a width of 2 μm and a thickness of about 3 μm. The thin film conductor coil pattern 10 could be formed. (E) On the thin-film conductor coil pattern 10 thus formed, an alumina insulating film 7 also serving as a gap layer is formed by using the bias sputtering method to flatten the unevenness, and the lower magnetic material pattern 6 is formed on the upper surface thereof. N partially connected to
The upper magnetic body pattern 11 made of iFe is formed. After this,
The whole was covered with a protective film 12 made of alumina to form a thin-film magnetic head on the substrate 1. The thin-film magnetic head manufactured through the above steps had no problem in characteristics as a magnetic head. In addition, since the manufacturing process of the thin film conductor coil pattern has been greatly simplified, the time required for manufacturing the thin film conductor coil pattern, which previously required about 20 hours for electrolytic plating, has been greatly reduced, and the production can be performed in about 2 hours. became. Further, with the simplification of the process, the number of people required for the work and the number of required devices can be greatly reduced as compared with the related art, and the manufacturing cost of the thin film magnetic head can be suppressed as a whole. Note that the various materials and process methods used in the above-described thin film magnetic head manufacturing process are merely examples, and the effects of the present invention are not impaired by using other materials and methods. (Embodiment 3) Next, an embodiment of a magnetoresistive head using the Cu-based thin film conductor alloy material of the present invention will be described with reference to FIG. (A) on the substrate 1 made of alumina film with Al ₂ O ₃ -TiC sintered body, the soft magnetic film made of magnetic shield 13, the insulating film 7, the multilayer film of the magnetoresistive element made of a magnetoresistive film 14 A pattern is formed, and the C
The u-based thin film conductor alloy material 2 is formed. In this embodiment, NiFe (permalloy) is used as the magnetoresistive effect film 14,
Cu-8 at% Sn- as the Cu-based thin film conductor alloy material 2
A 0.1% P alloy was deposited to a thickness of 1 μm. The multilayer film pattern of the magnetoresistive element was formed by an ultra-high vacuum evaporation method, and the Cu-based thin film conductor alloy material 2 was formed by a sputtering method. (B) Next, a photoresist 3 is applied on the Cu-based thin film conductor alloy material 2 and is patterned into a desired thin film conductor pattern. In this embodiment, AZ manufactured by Shipley Co., Ltd.
Using 1350J, a resist pattern was formed such that the thin film conductor pattern was placed in contact with both ends of the magnetoresistive film 14. The film pressure of the photoresist 3 is 2 μm,
The minimum width of the pattern is 2 μm. (C) Subsequently, they are introduced into a reactive ion etching apparatus. The equipment contains SiCl ₄ as chlorine-based gas for 5 seconds.
ccm, Cl ₂ at 3 sccm, and N ₂ as a mixed gas.
0 sccm, 5 sccm of NH ₃ , gas pressure 3P
a, 1 at 200 W input power and 180 ° C. substrate temperature
A high-frequency plasma 4 of 3.56 MHz was generated, and reactive ion etching was performed. (D) As a final step of pattern formation, the substrate 1 after etching is taken out of the reactive ion etching apparatus, and the photoresist 3 is peeled off using an organic solvent. As a result, a thin film having a rectangular shape and a width of 2 μm and a thickness of about 1 μm is obtained. The conductor pattern 5 was able to be formed. Further, since the selectivity of NiFre between the Cu-based thin film conductor alloy material 2 and the magnetoresistive effect film 14 can be made very large, etching damage to the magnetoresistive effect film 14 which is a part of the base during etching is caused by the scanning electron beam. Neither was observed under a microscope nor on soft magnetic characteristics. In addition, since the wafer was sufficiently smaller than the high frequency plasma 4 for etching, the in-plane distribution of the amount of 4 etching also showed a value close to zero. These problems, which have been a problem in the prior art, can prevent the magnetoresistive film 14 from being damaged by overetching.
This shows that the problem can be avoided by using the u-based conductor wiring material 2. (E) On the thin-film conductor pattern 5 thus formed, an insulating film 7 made of alumina also serving as a gap layer is formed by a sputtering method, and a pattern of the magnetic shield 13 is formed again on the upper surface thereof. Thereafter, the whole was covered with a protective film 12 made of alumina to form a magnetoresistive head on the substrate 1. Since the magnetoresistive head manufactured through the above-described steps has undergone only a low-temperature process, there was no problem in characteristics as a magnetic head. The various materials and process methods used in the manufacturing process of the magnetoresistive head are merely examples, and the effects of the present invention are not impaired by using other materials and methods.

[0033]

As described above, by using the Cu-based thin film conductor alloy material of the present invention, a long-term reliable magnetic head and a magnetic head manufactured without deteriorating the performance of the magnetic film during the production of the thin film conductor pattern. A magnetic thin film device such as a sensor can be manufactured. Further, by using the material,
Conventional process for manufacturing thin film conductor patterns by plating maintains the continuity of the process by a dry process, reduces the total number of processes compared to the conventional manufacturing process, simplifies it, reduces equipment costs, and manufactures quickly In addition, a photoresist which can be easily peeled off after etching and which can simplify the process can be used as a mask material for etching when forming a thin film conductor pattern.
Reactive ion etching becomes possible at temperatures below ℃,
In addition, it is possible to lower the temperature during etching while using an etching gas that does not deteriorate the properties of the conductor material due to oxidation or the like during etching, and to form a fine thin film conductor pattern having a width of 5 μm or less.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the etching temperature and the amount of Al added to show the effect of the Cu-based thin film conductor alloy material of the present invention.

FIG. 2 is a sectional view showing a manufacturing process of a thin film conductor pattern using the Cu-based thin film conductor alloy material of the present invention.

FIG. 3 is a sectional view of a manufacturing process of a thin-film magnetic head using the Cu-based thin-film conductor alloy material of the present invention.

FIG. 4 is a sectional view showing a manufacturing process of a magnetoresistive head using the Cu-based thin film conductor alloy material of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Cu-based thin film conductor alloy material 3 Photoresist 4 High frequency plasma 5 Thin film conductor pattern 6 Lower magnetic body pattern 7 Insulating film 8 Cr film 9 Ion beam 10 Thin film conductor coil pattern 11 Upper magnetic body pattern 12 Protective film 13 Magnetic shield 14 Magnetoresistive film

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location H05K 1/09 H05K 1/09 A // H01B 5/14 H01B 5/14 Z

Claims (4)

(57) [Claims] 1. B, C, N, Al, S for Cu
i, P, S, Ga, Ge, As, Se, In, Sn, S
b, Te, Bi, Po, Be, Ti, V, Zr, Nb,
A Cu-based thin film conductor alloy material to which at least one of Mo, Tc, Hf, Ta, W, Re, Pa, and U is added, wherein the lower limit (W ⁿ [at
As%]), and the addition amount of each additive element k, between the boiling point of the chloride of the additive element ^{(T b k [K])} , Equation 1 is satisfied, the amount of additive elements for Cu As an upper limit,
A Cu-based thin film conductor alloy material, characterized by adding an additional element within a range having at least a part of the same crystal structure as pure Cu. (Equation 1) 2. The method for etching a Cu-based thin film conductor alloy material according to claim 1, wherein the etching is performed using a gas containing chlorine in a temperature range of 180 ° C. or lower. 3. A non-magnetic layer forming a gap on a substrate, a spiral conductor on an insulator, and generating a magnetic field near the center by applying a current to the conductor from the outside, or In a thin-film magnetic head having upper and lower magnetic poles made of a soft magnetic film sandwiched between a thin-film conductor pattern capable of generating an induced current in a conductor by changing a magnetic field in the vicinity thereof, the thin-film conductor pattern is Item 7. A thin film magnetic head made of the Cu-based thin film conductor alloy material according to Item 1. 4. The Cu-based thin-film conductor alloy according to claim 1, wherein the thin-film conductor pattern has at least a magneto-resistance effect element and a thin-film conductor pattern arranged in contact with the magneto-resistance effect element. A magnetoresistive head, which is formed of a material.