JP2004206822A - Manufacturing method of thin film magnetic head having magnetoresistve effect element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a thin film magnetic head having an MR element, with which the MR element whose track width is 200nm or less and where a current is made to flow in a direction vertical to a laminating plane can be easily manufactured. <P>SOLUTION: An MR lamination body taking out the output by making the current flow in the direction vertical to a lamination plane and a cap body made of a low coercive force ferromagnetic material laminated on the MR lamination body and having conductivity are formed on a lower part electrode film. Insulation films are laminated on the formed cap body and the lower part electrode film. The laminated insulation films are removed until at lease a part of the cap body is protruded on the laminated insulation film. The upper part electrode film is formed on the removed insulation film and the cap body. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a thin film magnetic head having a magnetoresistive (MR) element for reading out a magnetic field intensity of a magnetic recording medium or the like as a signal.
[0002]
2. Description of the Related Art High-capacity and high-output thin-film magnetic heads have been required as hard disk drives (HDDs) have become larger and smaller. To meet this demand, the characteristics of the current product, a GMR head having a giant magnetoresistive effect (GMR) element, are being improved, while the tunnel magnetoresistive effect, which can expect a resistance change rate more than twice that of the GMR head, is expected. Development of a TMR head having a (TMR) element is also being vigorously conducted.
[0003]
The head structures of a TMR head and a general GMR head are different from each other due to a difference in the direction in which a sense current flows. A head structure in which a sense current flows in parallel to a lamination surface (film surface) like a general GMR head is called a CIP (Current In Plane) structure, and a sense current is perpendicular to the film surface like a TMR head. Is called a CPP (Current Perpendicular to Plane) structure.
[0004]
In recent years, a GMR head having a CPP structure instead of a CIP structure has been developed (for example, Patent Document 1). Further, a GMR head having a CPP structure having an antiferromagnetic coupling type magnetic multilayer film composed of a plurality of magnetic layers stacked via non-magnetic layers (Cu, Ag, Au, etc.) is also known (Patent Documents 2, 3, and 5). 4).
[0005]
As a recent GMR head having a CPP structure, a GMR head having a spin valve magnetic multilayer film (including a specular magnetic multilayer film and a dual spin valve magnetic multilayer film) similar to the case of the CIP structure GMR head has been studied. .
[0006]
In the case of forming a GMR head or a TMR head having such a CPP structure, conventionally, a lift-off method, a contact hole method, or the like has been used.
[0007]
FIG. 1 is a cross-sectional view showing a partial step of forming a GMR head having a CPP structure by a lift-off method.
[0008]
As shown in FIG. 1A, first, a lower electrode film 11 and an MR multilayer film 12 'are sequentially laminated on an insulating film 10 formed on a substrate (not shown).
[0009]
Next, as shown in FIG. 2B, a two-layer photoresist pattern 13 is formed thereon, and as shown in FIG. 2C, the MR multilayer film 12 'is patterned by ion milling to form an MR stack. Obtain body 12.
[0010]
Next, an insulating film 14 'is formed as shown in FIG. 4D, and the photoresist pattern 13 is peeled off as shown in FIG. 4E, that is, the insulating film 14 is obtained by lift-off.
[0011]
Thereafter, as shown in FIG. 1F, an upper electrode film 15 is formed thereon.
[0012]
In such a lift-off method, it is necessary to prevent the insulating film 14 'from adhering to the side wall of the step portion of the two-layer photoresist pattern 13 and connecting the insulating film 14' across the step portion. Therefore, the lift-off property is usually improved by forming an eaves-like undercut using a two-layer photoresist pattern.
[0013]
However, if the amount of undercut of the photoresist pattern 13 is small, an insulating film is deposited on the side wall of the base 13a of the two-layered photoresist pattern 13, and unnecessary deposition is performed around the position where the photoresist pattern 13 exists after lift-off. Burrs are generated. By increasing the amount of undercut, the occurrence of such burrs can be suppressed, but the resist width of the base portion 13a, which is the undercut portion, becomes extremely thin, and there is a possibility that pattern collapse or the like may occur.
[0014]
Further, as shown in FIG. 3E, the insulating film 14 which has wrapped around the undercut portion overlaps the upper surface of the MR laminate 12, and the track width becomes unclear. Limits arise. Since the overlap by the lift-off method is about 100 nm, when the track width becomes 200 nm or less, for example, 100 nm like a recent TMR element or GMR element, the function as the GMR element or TMR element no longer functions. I can't expect anything at all.
[0015]
Generally, in an MR stack of a TMR element and a GMR element, the free layer is located in the middle of the MR stack, and the width thereof defines the track width. Therefore, when the MR laminate is formed by ion milling using a conventional photoresist as a mask, the skirt of the MR laminate is widened, and the effective track width is increased. Ideally, the side walls of the MR stack are desirably perpendicular to the substrate surface, and this can be achieved by ion milling using a hard mask, reactive ion etching (RIE), or the like. Exists. However, none of these can be used in principle for the lift-off method.
[0016]
FIG. 2 is a cross-sectional view showing a partial step of forming a GMR head having a CPP structure by a contact hole method.
[0017]
As shown in FIG. 1A, first, a lower electrode film 21 and an MR multilayer film 22 'are sequentially laminated on an insulating film 20 formed on a substrate (not shown).
[0018]
Next, as shown in FIG. 4B, a photoresist pattern 23 is formed thereon, and as shown in FIG. 4C, the MR multilayer film 22 'is patterned by ion milling to form the MR multilayer body 22. obtain.
[0019]
Next, as shown in FIG. 3D, after the photoresist pattern 23 is peeled off, an insulating film 24 'is formed.
[0020]
Next, as shown in FIG. 3E, a photoresist pattern 26 having an opening 26a corresponding to the contact hole is formed on the insulating film 24 '.
[0021]
Next, as shown in FIG. 2F, after the insulating film 24 'is subjected to ion milling to obtain an insulating film 24 having a contact hole 24a on the MR laminate 22, the photoresist pattern 26 is peeled off.
[0022]
Thereafter, as shown in FIG. 3G, an upper electrode film 25 is formed thereon.
[0023]
In such a contact hole method, two photo processes for the resist pattern are performed, and therefore, an overlap generated by misalignment caused by the photo process is about 30 nm. This is not negligible as in the case of the lift-off method.
[0024]
According to the conventional techniques described above, it is extremely difficult to realize a GMR head or a TMR head having a CPP structure with a track width of 200 nm or less, and it is required to establish a new method capable of avoiding these. .
[0025]
As a method of fabricating a GMR head or a TMR head having a CPP structure without using a contact hole method, a lower electrode, a magnetic sensor film, and a protective film made of a soft magnetic material are laminated on a substrate, and the magnetic sensor film and the protective film are etched. After the burying layer is deposited on the entire surface, the entire surface is polished by a planarization technique such as chemical mechanical polishing (CMP) until the protective film made of a soft magnetic material is exposed. The sensor film, protective film and planarization buried layer are patterned by etching, an insulating layer is deposited on the entire surface, and then polished again by a planarization technique such as CMP until the protective film made of a soft magnetic material is exposed, and the whole is polished. After planarization, a method of forming an upper electrode thereon has been proposed (Patent Document 5).
[0026]
[Patent Document 1]
JP-A-5-275770
[Patent Document 2]
JP-A-4-360009
[Patent Document 3]
JP-A-5-90026
[Patent Document 4]
JP-A-9-129445
[Patent Document 5]
JP 2002-123916 A
[0027]
However, as in the technique described in Patent Document 5, the entire surface is flattened by a flattening technique such as CMP until the protective film is exposed, and an upper electrode is formed thereon. According to the method, it is very difficult to uniformly control the planarization over the entire surface of the wafer, and it is not possible to efficiently manufacture a highly accurate element. In addition, since it is difficult to control the CMP with an accuracy of about several nm, when the planarization is performed by this, in an extreme case, the insulating layer 34 between the lower electrode film 31 and the upper electrode film 35 is formed as shown in FIG. Is not uniform, and also varies between the elements in the wafer. In the figure, reference numeral 32 denotes an MR laminated body, and 33 denotes a protective film made of a soft magnetic material laminated thereon, that is, a cap body. In the case of actually manufacturing such a head, it is very difficult to planarize the protective film 33 so that the protective layer 33 and the insulating layer 34 coincide with each other. High-precision planarization cannot be performed over the entire surface.
[0028]
Therefore, an object of the present invention is to provide a method of manufacturing a thin film magnetic head having an MR element, which can easily manufacture an MR element having a track width of 200 nm or less and in which a current flows in a direction perpendicular to the lamination plane. is there.
[0029]
Another object of the present invention is to provide a method of manufacturing a thin-film magnetic head having an MR element, which can easily perform patterning of the MR element using a hard mask.
[0030]
Still another object of the present invention is to provide a method of manufacturing a thin film magnetic head having an MR element, in which it is not necessary to flatten a cap body and an insulating layer on an MR stack.
[0031]
[Means for Solving the Problems]
According to the present invention, an MR laminated body for taking out an output by flowing a current in a direction perpendicular to the laminating plane on a lower electrode film, and a cap made of a low-coercivity ferromagnetic material having conductivity laminated on the MR laminated body And an insulating film is laminated on the formed cap body and the lower electrode film, and the laminated insulating film is removed until at least a part of the cap body protrudes above the laminated insulating film, and the removed insulating film is removed. And a method of manufacturing a thin-film magnetic head having an MR element for forming an upper electrode film on a cap body.
[0032]
A cap body made of a low coercivity ferromagnetic material having conductivity is formed on the MR laminated body, and an insulating film is laminated thereon and on the lower electrode film until at least a part of the cap body protrudes on the insulating film. By removing the laminated insulating film and forming the upper electrode film on the removed insulating film and the cap body, the cap body is regarded as a part of the upper electrode film, and the lead gap width is reduced to the MR laminated body. The thickness can be determined. Since the read gap width can be strictly defined in this way, it is possible to prevent the magnetic properties from deteriorating. Further, since the lead gap width is determined by the thickness of the MR laminate, a narrower read gap can be achieved.
[0033]
In particular, in the present invention, instead of flattening the insulating film by CMP or the like until the cap body is exposed as in Patent Document 5, a cue that removes the insulating film until a part of the cap body protrudes from the insulating film. Since only the treatment is performed, the insulating film can be uniformly removed, so that the upper and lower electrode films can be arranged in parallel with each other. In addition, since the insulating film can be uniformly removed over the entire surface of the wafer, a highly accurate element having no variation can be efficiently manufactured. Moreover, since the insulating film is removed so that a part of the cap body protrudes from the insulating film, a margin for removing the insulating film can be larger than when the cap body and the insulating film are flattened. Thus, the production can be facilitated.
[0034]
Furthermore, according to such a manufacturing method, generation of burrs, overlaps, and the like of the insulating film cannot occur, and a more strict definition of the track width becomes possible. Therefore, the track width is 200 nm or less, and the track width is 200 nm or less. An MR element in which current flows in one direction can be easily manufactured.
[0035]
Laminating an MR multilayer film on the lower electrode film, laminating a cap film made of a low coercivity ferromagnetic material having conductivity on the MR multilayer film, forming a mask on the laminated cap film, and patterning the cap film. It is preferable to form an MR laminated body by forming a cap body by using and then patterning the MR multilayer film using the cap body as a hard mask. By using the cap body as a hard mask, it is possible to use RIE for patterning, which can suppress the spread of the MR multilayer body.
[0036]
An MR multilayer film is laminated on the lower electrode film, a cap film made of a low coercivity ferromagnetic material having conductivity is laminated on the MR multilayer film, and a mask is formed on the laminated cap film to form the cap film and the MR film. After patterning the multilayer film, it is also preferable to form the cap body and the MR laminated body by removing the mask.
[0037]
After stacking the MR multilayer film on the lower electrode film, forming a resist trench pattern on the MR multilayer film, and forming a cap film of a low coercivity ferromagnetic material having conductivity through the formed resist trench pattern. It is also preferable to form a cap by removing the resist trench pattern and pattern the MR multilayer film using the cap as a hard mask to form an MR multilayer. In this case, it is more preferable that the cap film is formed by a dry thin film formation method or a frame plating method.
[0038]
After the insulating film is selectively removed until the protruding height (b) of the insulating film on the cap body is smaller than the height (a) of the cap body (b <a). Preferably, the entire insulating film is removed until at least a part of the cap body protrudes above the insulating film.
[0039]
The removal of the insulating film is performed by etching, and the etching rate of the cap body in this etching is preferably lower than the etching rate of the insulating film. This is because, if the etching rate of the insulating film is lower, as soon as the cap body is exposed, the etching of the cap body proceeds, and a desired shape may not be obtained.
[0040]
It is preferable to remove the insulating film so that a part of the cap body projects from the lower surface of the upper electrode film.
[0041]
It is most preferable that the cap body is formed of the same material as the upper electrode film, but it is also effective to form the cap body with a material different from the upper electrode film as long as it is a conductive ferromagnetic material having a small coercive force. . For example, based on iron, nickel, and cobalt, such as NiFe and CoFe, alloys such as tantalum, zirconium, and hafnium mixed, and sendust-based alloys doped with aluminum and silicon, and nitrogen-, boron-, and carbon-added alloys Alloys. However, it is important to use a cap material having an etching rate lower than the etching rate of the insulating film when etching the lead gap insulating film. This is because, if the etching rate of the insulating film is lower, as soon as the cap body is exposed, the etching of the cap body proceeds, and a desired shape may not be obtained.
[0042]
It is also preferable that a non-magnetic conductive gap film is laminated between the lower electrode film and the MR laminate, and a non-magnetic conductive gap film is further laminated between the MR laminate and the cap.
[0043]
The MR stack has a TMR stack, a GMR stack having a CPP structure, a TMR stack including a bias layer for defining a magnetization direction for a free layer, or a CPP structure including a bias layer for defining a magnetization direction for a free layer. It is preferably a GMR laminate.
[0044]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 4 is a sectional view showing a partial step of forming a TMR head or a GMR head having a CPP structure as one embodiment of the present invention.
[0045]
First, as shown in FIG. 1A, a lower electrode film 41 also serving as a magnetic shield film, a gap film 42 'made of a nonmagnetic conductive material, and an MR multilayer are formed on an insulating film 40 formed on a substrate (not shown). A film 43 ′, a gap film 44 ′ made of a non-magnetic conductive material and a cap film 45 ″ are sequentially laminated by being formed using a dry thin film formation method, and a photoresist pattern having straight-shaped side walls thereon is formed. 46 is formed. The dry thin film formation method is a vacuum thin film formation method including an evaporation method, a sputtering method, a CVD method, and the like.
[0046]
In this embodiment, the cap film 45 ″ is formed by forming the same material as the upper electrode film 48 described later, for example, NiFe (permalloy) by using a dry thin film forming method.
[0047]
Next, as shown in FIG. 3B, the cap layer 45 '' is etched using the photoresist pattern 46 as a mask to form a cap body 45 'serving as a hard mask.
[0048]
Next, as shown in FIG. 5C, after the resist pattern 46 is peeled off, the gap film 42 ', the MR multilayer film 43' and the gap film 42 'are subjected to reactive ion etching (RIE) using the cap body 45 as a hard mask. 44 'is patterned to obtain a gap film 42, an MR laminated body 43, and a gap film 44 as shown in FIG.
[0049]
The MR laminated body 43 includes a TMR laminated body, a GMR laminated body having a CPP structure, a TMR laminated body including a bias layer for defining a magnetization direction with respect to a free layer, a GMR laminated body having a CPP structure, and an antiferromagnetic coupling type magnetic multilayer film. For example, a GMR laminate having a CPP structure, a GMR laminate having a CPP structure having a specular spin-valve magnetic multilayer film, a GMR laminate having a CPP structure having a dual spin valve magnetic multilayer film, or the like.
[0050]
Next, as shown in FIG. 9E, the junction portion which is the upper surface portion of the MR laminate 43 and the cap body 45 ′ has a convex shape, for example, Al. ₂ O ₃ Or SiO ₂ Is formed on the entire surface by a dry thin film forming method such as a sputtering method. The insulating film 47 ″ is formed such that the convex protrusion height b is larger than the height a of the cap body 45 ′.
[0051]
Thereafter, as shown in FIG. 2F, the upper portion of the convex junction of the insulating film 47 '' is removed by selective etching using high bias RIE. This selective removal is performed until the protruding height b of the insulating film 47 'becomes smaller than the height a of the cap body 45' (b <a).
[0052]
Next, the entire insulating film 47 'is milled at the same milling rate, and the upper surface (junction) of the cap body 45' is exposed, and the insulating film 47 'is removed by milling until a part thereof protrudes from the insulating film 47'. I do. As a result, the cap body 45 is caught, that is, the top is exposed, and a part thereof is protruded from the upper surface of the insulating film 47. In this case, the insulating film 47 'is not removed to the bottom surface of the cap body 45. That is, as shown in FIG. 9G, the insulating film 47 'is removed so that the depth c downward from the upper surface of the insulating film 47 of the cap body 45 becomes larger than zero (c> 0). This c is generally several to several tens of degrees or more.
[0053]
Next, as shown in FIG. 3H, an upper electrode film 48 also serving as a magnetic shield film is formed on the insulating film 47 and the cap body 45 by a dry thin film forming method such as a sputtering method.
[0054]
In the present embodiment, since the cap body 45 and the upper electrode film 48 are formed of the same material, the cap body 45 can be regarded as a part of the upper electrode film 48, and the read gap width is set to the gap film 42 and the MR film. It can be defined as the total thickness of the stacked body 43 and the gap film 44. As a result, the read gap width can be strictly defined, so that deterioration of the magnetic characteristics can be prevented. Further, since the read gap width is the total thickness of the gap film 42, the MR stack 43, and the gap film 44, a narrower read gap can be achieved.
[0055]
The cap body 45 is effective even if it is made of a conductive ferromagnetic material having a small coercive force and a material different from that of the upper electrode film 48. For example, in addition to NiFe, an alloy in which tantalum, zirconium, hafnium, or the like is mixed based on iron, nickel, or cobalt, a sendust-based alloy in which aluminum or silicon is doped, nitrogen, boron, carbon, or the like is added in addition to NiFe. Alloys of the following series. However, it is important to use a material having an etching rate lower than the etching rate of the insulating film 47 'when performing cueing of the cap body 45'. This is because if the etching rate of the insulating film 47 'is lower, as soon as the cap body 45' is exposed, the etching of the cap body may proceed, and a desired shape may not be obtained.
[0056]
Further, in the present embodiment, an insulating film 47 ″ is stacked on the MR multilayer 43, the cap 45 ′, and the lower electrode film 41, and the insulating film 47 ″ is formed until at least the upper surface of the cap 45 ′ is exposed. Since the MR laminate 43, the cap body 45 and the insulating film 47 around the MR laminate 43 are formed by selective etching and cue milling, an ordinary straight resist pattern or hard mask having no reverse taper should be used. Therefore, it is possible to form a finer MR laminated body than in the case of forming using a lift-off method. In addition, since the cap body 45 is used as a hard mask when the MR laminate 43 is milled, RIE or the like that can reduce the occurrence of tailing can be used, and this greatly contributes to improving the shape of the MR laminate 43. be able to. Furthermore, no burrs or overlaps of the insulating film 47 can occur, and a more strict definition of the track width is possible, so that an MR element having a track width of 200 nm or less can be easily manufactured.
[0057]
In addition, in the present embodiment, the insulating film 47 'is not planarized by CMP or the like until the cap body 45' is exposed, but the insulating film 47 'is not flattened until a part of the cap body 45' protrudes from the insulating film 47 '. Since the insulating film 47 'can be uniformly removed since the 47' is removed by milling, the upper and lower electrode films 48 and 41 can be arranged in parallel with each other. Further, since the insulating film 47 'can be uniformly removed over the entire surface of the wafer, a highly accurate device having no variation can be efficiently manufactured. In addition, since the insulating film 47 'is removed so that a part of the cap body 45' protrudes from the insulating film 47 ', a margin for removing the insulating film can be reduced as compared with the case where the cap body and the insulating film are flattened. Since it can be made large, production can be facilitated also in that sense.
[0058]
FIG. 5 is a sectional view schematically showing an example of the layer structure of the TMR head formed as described above.
[0059]
As shown in the figure, a lower electrode film 41 also serving as a magnetic shield film is laminated on the insulating film 40 to a thickness of about 2000 nm, and a lower layer 43a of a thickness of 0 to about 20 nm and A pinned layer 43b having a thickness of 10 to 20 nm, a pinned layer 43c having a thickness of about 5 to 6 nm, a tunnel barrier layer 43d having a thickness of about 1 nm, and a free layer 43e having a thickness of about 4 to 6 nm. An MR laminated body 43 is formed by sequentially laminating, and a cap body 45 and an upper electrode film 48 also serving as a magnetic shield film are laminated thereon to a thickness of about 2000 nm. The insulating film 47 is formed so as to surround the MR laminate 43 and the cap body 45. Note that the underlayer 43a having a thickness of 0 nm corresponds to a case without this underlayer.
[0060]
In the case of the GMR head having the CPP structure, the other configuration is the same as that of the TMR head except that a non-magnetic metal layer having a thickness of about 2 to 5 nm is formed in the portion of the tunnel barrier layer 43d. .
[0061]
FIG. 6 is a sectional view schematically showing another example of the layer structure of the TMR head.
[0062]
In this example, the TMR stacked body includes a bias layer that defines a magnetization direction with respect to the free layer. As shown in the figure, a lower electrode film 41 also serving as a magnetic shield film is laminated on the insulating film 40 to a thickness of about 2000 nm, and a lower layer 43a of a thickness of 0 to about 20 nm and A pinned layer 43b having a thickness of 10-20 nm, a pinned layer 43c having a thickness of about 5-6 nm, a tunnel barrier layer 43d having a thickness of about 1 nm, and a free layer 43e having a thickness of about 4-6 nm; An MR laminate 43 is formed by sequentially laminating a nonmagnetic metal layer 43f having a thickness of about 0.1 to 3 nm and an antiferromagnetic layer 43g having a thickness of about 10 nm, and a cap body 45 and a magnetic shield film are formed. And an upper electrode film 48, which also serves as a layer, is laminated to a thickness of about 2000 nm. The insulating film 47 is formed so as to surround the MR laminate 43 and the cap body 45. Note that the underlayer 43a having a thickness of 0 nm corresponds to a case without this underlayer.
[0063]
In the case of the GMR head having the CPP structure, the other configuration is the same as that of the TMR head except that a non-magnetic metal layer having a thickness of about 2 to 5 nm is formed in the portion of the tunnel barrier layer 43d. .
[0064]
FIG. 7 is a cross-sectional view showing a partial step of forming a TMR head or a GMR head having a CPP structure as another embodiment of the present invention.
[0065]
First, as shown in FIG. 1A, a lower electrode film 71 also serving as a magnetic shield film, a gap film 72 'made of a nonmagnetic conductive material, and an MR multilayer are formed on an insulating film 70 formed on a substrate (not shown). A film 73 ′, a gap film 74 ′ made of a non-magnetic conductive material, and a cap film 75 ″ are sequentially laminated by being formed using a dry thin film formation method, and a photoresist pattern having straight-shaped side walls thereon is formed. 76 is formed. The dry thin film formation method is a vacuum thin film formation method including an evaporation method, a sputtering method, a CVD method, and the like.
[0066]
In the present embodiment, the cap film 75 ″ is formed by forming the same material as the upper electrode film 78 described later, for example, NiFe (permalloy) by using a dry thin film forming method.
[0067]
Next, as shown in FIG. 3B, the cap layer 75 '' is etched using the photoresist pattern 76 as a mask to form a cap body 75 'serving as a hard mask.
[0068]
Next, as shown in FIG. 3C, after the resist pattern 76 is peeled off, RIE using the cap body 75 as a hard mask is performed to pattern the gap film 72 ′, the MR multilayer film 73 ′, and the gap film 74 ′. As shown in FIG. 3D, a gap film 72, an MR stack 73, and a gap film 74 are obtained.
[0069]
The MR laminated body 73 includes a TMR laminated body, a GMR laminated body having a CPP structure, a TMR laminated body including a bias layer for defining a magnetization direction with respect to a free layer, a GMR laminated body having a CPP structure, and an antiferromagnetic coupling type magnetic multilayer film. For example, a GMR laminated body having a CPP structure having a CPP structure, a GMR laminated body having a CPP structure having a specular spin-valve magnetic multilayer film, or a GMR laminated body having a CPP structure having a dual spin valve magnetic multilayer film.
[0070]
Next, as shown in FIG. 7E, the junction portion, which is the upper surface portion of the MR multilayer body 73 and the cap body 75 ', has a convex shape such as Al. ₂ O ₃ Or SiO ₂ Is formed on the entire surface by a dry thin film forming method such as a sputtering method. The insulating film 77 ″ is formed such that the convex protrusion height b is larger than the height a of the cap body 75 ′.
[0071]
Thereafter, as shown in FIG. 5F, the upper portion of the convex junction of the insulating film 77 '' is removed by dry flattening. This selective removal is performed until the protruding height b of the insulating film 77 'becomes smaller than the height a of the cap body 75' (b <a).
[0072]
The dry flattening process is a flattening process by low angle ion beam etching (IBE) in which a beam is incident at a low angle (an angle between an incident beam and the stacking surface is 0 to 40 degrees) with respect to the stacking surface. On the other hand, a flattening process using a low-angle IBE at which a beam is incident at a low angle and a low-rate IBE at a low etching rate, a low-angle IBE at which a beam is incident at a low angle with respect to a stacked surface, and a gas cluster ion beam (GCIB) are used. Means a flattening process using a low-rate IBE with a low etching rate, or a flattening process using a low-rate IBE with a low etching rate and a process using GCIB. The process using GCIB means that, for example, a gas such as Ar is injected into a high vacuum and rapidly cooled to form a cluster of the gas. This is to perform flattening.
[0073]
Next, the entire insulating film 77 'is milled at the same milling rate, and the upper surface (junction) of the cap body 75' is exposed, and the insulating film 77 'is removed by milling until a part thereof protrudes from the insulating film 77'. I do. As a result, the cap body 75 is caught, that is, the top is exposed, and a part thereof is protruded from the upper surface of the insulating film 77. In this case, the insulating film 77 ′ is not removed to the bottom of the cap body 75. That is, as shown in FIG. 9G, the insulating film 77 'is removed so that the depth c downward from the upper surface of the insulating film 77 of the cap body 75 becomes larger than zero (c> 0). This c is generally several to several tens of degrees or more.
[0074]
Next, as shown in FIG. 2H, an upper electrode film 78 which also serves as a magnetic shield film is formed on the insulating film 77 and the cap body 75 by a dry thin film forming method such as a sputtering method.
[0075]
In the present embodiment, since the cap body 75 and the upper electrode film 78 are formed of the same material, the cap body 75 can be considered as a part of the upper electrode film 78, and the read gap width is set to the gap film 72 and the MR film. It can be defined as the total thickness of the stacked body 73 and the gap film 74. As a result, the read gap width can be strictly defined, so that deterioration of the magnetic characteristics can be prevented. Further, since the read gap width is the total thickness of the gap film 72, the MR stack 73, and the gap film 74, a narrower read gap can be achieved.
[0076]
The cap body 75 is effective even if it is made of a conductive ferromagnetic material having a small coercive force and a material different from that of the upper electrode film 78. For example, in addition to NiFe, an alloy in which tantalum, zirconium, hafnium, or the like is mixed based on iron, nickel, or cobalt, a sendust-based alloy in which aluminum or silicon is doped, nitrogen, boron, carbon, or the like is added in addition to NiFe. Alloys of the following series. However, it is important to use a material having an etching rate lower than the etching rate of the insulating film 77 'when performing cueing of the cap body 75'. This is because if the etching rate of the insulating film 77 'is lower, as soon as the cap body 75' is exposed, the etching of the cap body proceeds, and a desired shape may not be obtained.
[0077]
In the present embodiment, an insulating film 77 ″ is stacked on the MR multilayer 73, the cap 75 ′, and the lower electrode film 71, and the insulating film 77 ″ is formed until at least the upper surface of the cap 75 ′ is exposed. Since the MR laminated body 73, the cap body 75, and the insulating film 77 around the MR laminated body 73 are formed by dry flattening and cue milling, an ordinary straight resist pattern or hard mask having no reverse taper should be used. Therefore, it is possible to form a finer MR laminated body than in the case of forming using a lift-off method. In addition, since the cap body 75 is used as a hard mask when the MR laminate 73 is milled, RIE or the like that can reduce the occurrence of tailing can be utilized, and greatly contributes to the improvement of the shape of the MR laminate 73. be able to. Furthermore, no burr or overlap of the insulating film 77 can occur, and a more strict definition of the track width is possible. Therefore, an MR element having a track width of 200 nm or less can be easily manufactured.
[0078]
In addition, in the present embodiment, the insulating film 77 'is not planarized by CMP or the like until the cap body 75' is exposed, but the insulating film 77 'is not flattened until a part of the cap body 75' protrudes from the insulating film 77 '. Since the insulating film 77 'can be uniformly removed because the 77' is removed by milling, the upper and lower electrode films 78 and 71 can be arranged in parallel with each other. In addition, since the insulating film 77 'can be uniformly removed over the entire surface of the wafer, a highly accurate device having no variation can be efficiently manufactured. In addition, since the insulating film 77 'is removed so that a part of the cap body 75' protrudes from the insulating film 77 ', the margin for removing the insulating film is greater than when the cap body and the insulating film are flattened. Since it can be made large, production can be facilitated also in that sense.
[0079]
FIG. 8 is a cross-sectional view showing a partial step of forming a TMR head or a GMR head having a CPP structure as still another embodiment of the present invention.
[0080]
First, as shown in FIG. 1A, a lower electrode film 81 also serving as a magnetic shield film, a gap film 82 'made of a nonmagnetic conductive material, and an MR multilayer are formed on an insulating film 80 formed on a substrate (not shown). A film 83 ′, a gap film 84 ′ made of a nonmagnetic conductive material, and a cap film 85 ″ are sequentially formed by being formed using a dry thin film formation method, and a photoresist pattern having straight-shaped side walls thereon is formed. 86 is formed. The dry thin film formation method is a vacuum thin film formation method including an evaporation method, a sputtering method, a CVD method, and the like.
[0081]
In the present embodiment, the cap film 85 ″ is formed by forming the same material as the upper electrode film 88 described later, for example, NiFe (permalloy) by using a dry thin film forming method.
[0082]
Next, IBE is performed using the photoresist pattern 86 as a mask, the cap layer 85 ″, the gap film 84 ′, the MR multilayer film 83 ′ and the gap film 82 ′ are patterned, and the resist pattern 86 is peeled off. As shown in (B), a gap film 82, an MR stack 83, a gap film 84, and a cap body 85 'are obtained.
[0083]
The MR laminated body 83 includes a TMR laminated body, a GMR laminated body having a CPP structure, a TMR laminated body including a bias layer for defining a magnetization direction with respect to a free layer, a GMR laminated body having a CPP structure, and an antiferromagnetically coupled magnetic multilayer film. For example, a GMR laminated body having a CPP structure having a CPP structure, a GMR laminated body having a CPP structure having a specular spin-valve magnetic multilayer film, or a GMR laminated body having a CPP structure having a dual spin valve magnetic multilayer film.
[0084]
Next, as shown in FIG. 7C, the junction portion, which is the upper surface portion of the MR laminate 83 and the cap body 85 ′, has a convex shape such as Al. ₂ O ₃ Or SiO ₂ Is formed on the entire surface by a dry thin film forming method such as a sputtering method. The insulating film 87 ″ is formed such that its convex protrusion height b is larger than the height a of the cap body 85 ′.
[0085]
Thereafter, as shown in FIG. 3D, the upper portion of the convex junction of the insulating film 87 ″ is removed by dry flattening. This selective removal is performed until the protruding height b of the insulating film 87 'becomes smaller than the height a of the cap body 85' (b <a).
[0086]
The dry flattening process is a flattening process by a low angle IBE in which a beam is incident at a low angle (an angle between an incident beam and the stacking surface is 0 to 40 degrees) with respect to the stacking surface, and a beam at a low angle with respect to the stacking surface A low-angle IBE with a low angle IBE and a low-rate IBE with a low etching rate, a low-angle IBE with a beam incident at a low angle on the stacking surface, and a processing with a GCIB and a low-rate IBE with a low etching rate. Or a flattening process using GCIB and a low-rate IBE with a low etching rate.
[0087]
Next, the entire insulating film 87 'is milled at the same milling rate, and the upper surface (junction) of the cap body 85' is exposed, and the insulating film 87 'is removed by milling until a part thereof protrudes from the insulating film 87'. I do. As a result, a capped body 85 is obtained, that is, a top is exposed, that is, the top is exposed, and a part thereof protrudes from the upper surface of the insulating film 87. In this case, the insulating film 87 ′ is not removed to the bottom of the cap body 85. That is, as shown in FIG. 9E, the insulating film 87 'is removed so that the depth c downward from the upper surface of the insulating film 87 of the cap body 85 becomes larger than zero (c> 0). This c is generally several to several tens of degrees or more.
[0088]
Next, as shown in FIG. 3F, an upper electrode film 88 which also serves as a magnetic shield film is formed on the insulating film 87 and the cap body 85 by a dry thin film forming method such as a sputtering method.
[0089]
In the present embodiment, since the cap body 85 and the upper electrode film 88 are formed of the same material, the cap body 85 can be regarded as a part of the upper electrode film 88, and the read gap width can be reduced by the gap film 82 and the MR film. It can be defined as the total thickness of the stacked body 83 and the gap film 84. As a result, the read gap width can be strictly defined, so that deterioration of the magnetic characteristics can be prevented. Further, since the read gap width is the total thickness of the gap film 82, the MR stack 83, and the gap film 84, a narrower read gap can be achieved.
[0090]
The cap body 85 is effective even if it is made of a conductive ferromagnetic material having a small coercive force and a material different from that of the upper electrode film 88. For example, in addition to NiFe, an alloy in which tantalum, zirconium, hafnium, or the like is mixed based on iron, nickel, or cobalt, a sendust-based alloy in which aluminum or silicon is doped, nitrogen, boron, carbon, or the like is added in addition to NiFe. Alloys of the following series. However, it is important to use a material having an etching rate lower than the etching rate of the insulating film 87 'when performing cueing of the cap body 85'. This is because if the etching rate of the insulating film 87 'is lower, as soon as the cap body 85' is exposed, the etching of the cap body may proceed, and a desired shape may not be obtained.
[0091]
In the present embodiment, an insulating film 87 '' is laminated on the MR laminated body 83, the cap body 85 ', and the lower electrode film 81, and the insulating film 87''is formed until at least the upper surface of the cap body 85' is exposed. Since the MR laminated body 83, the cap body 85, and the insulating film 87 around the MR laminated body 83, the cap body 85, and the surrounding insulating film 87 are formed by dry flattening and cue milling, an ordinary straight resist pattern or hard mask having no reverse taper should be used. Therefore, it is possible to form a finer MR laminated body than in the case of forming using a lift-off method. In addition, since IBE that can reduce the occurrence of tailing when the MR stack 83 is milled is used, it can greatly contribute to improving the shape of the MR stack 83. Furthermore, burrs and overlaps of the insulating film 87 cannot occur, and a more strict definition of the track width is possible. Therefore, an MR element having a track width of 200 nm or less can be easily manufactured.
[0092]
In addition, in the present embodiment, the insulating film 87 'is not flattened by CMP or the like until the cap body 85' is exposed, but the insulating film 87 'is not flattened until a part of the cap body 85' protrudes from the insulating film 87 '. Since the insulating film 87 'can be removed uniformly by milling the 87', the upper and lower electrode films 88 and 81 can be arranged in parallel with each other. Further, since the insulating film 87 'can be uniformly removed over the entire surface of the wafer, a highly accurate device having no variation can be efficiently manufactured. In addition, since the insulating film 87 'is removed so that a part of the cap body 85' protrudes from the insulating film 87 ', a margin for removing the insulating film can be reduced as compared with the case where the cap body and the insulating film are flattened. Since it can be made large, production can be facilitated also in that sense.
[0093]
FIG. 9 is a cross-sectional view showing a partial step of forming a TMR head or a GMR head having a CPP structure as still another embodiment of the present invention.
[0094]
First, as shown in FIG. 1A, a lower electrode film 91 also serving as a magnetic shield film, a gap film 92 'made of a nonmagnetic conductive material, and an MR multilayer are formed on an insulating film 90 formed on a substrate (not shown). A film 93 ′ and a gap film 94 ′ made of a non-magnetic conductive material are sequentially laminated by being formed using a dry thin film forming method, and a photoresist trench pattern 96 is formed thereon, and then a cap film is formed thereon. 95 '' is deposited. The dry thin film formation method is a vacuum thin film formation method including an evaporation method, a sputtering method, a CVD method, and the like.
[0095]
In the present embodiment, the cap film 95 ″ is formed by forming the same material as the upper electrode film 98 described later, for example, NiFe (permalloy) using a dry thin film forming method.
[0096]
Next, as shown in FIG. 7B, the photoresist trench pattern 96 is peeled off, that is, lifted off to form a cap body 95 ′ serving as a hard mask.
[0097]
Next, the gap film 92 ', the MR multilayer film 93' and the gap film 94 'are patterned by milling or RIE using this hard mask, and as shown in FIG. And a gap film 94 is obtained.
[0098]
The MR laminated body 93 includes a TMR laminated body, a GMR laminated body having a CPP structure, a TMR laminated body including a bias layer for defining a magnetization direction with respect to a free layer, a GMR laminated body having a CPP structure, and an antiferromagnetically coupled magnetic multilayer film. For example, a GMR laminated body having a CPP structure having a CPP structure, a GMR laminated body having a CPP structure having a specular spin-valve magnetic multilayer film, or a GMR laminated body having a CPP structure having a dual spin valve magnetic multilayer film.
[0099]
Next, as shown in FIG. 4D, the junction portion which is the upper surface portion of the MR laminated body 93 and the cap body 95 ′ has a convex shape such as Al. ₂ O ₃ Or SiO ₂ Is formed on the entire surface by a dry thin film forming method such as a sputtering method. The insulating film 97 ″ is formed such that its convex protrusion height b is larger than the height a of the cap body 95 ′.
[0100]
Thereafter, as shown in FIG. 3E, the upper portion of the convex junction of the insulating film 97 '' is removed by selective etching using high bias RIE. This selective removal is performed until the convex protrusion height b of the insulating film 97 'becomes smaller than the height a of the cap body 95' (b <a).
[0101]
Next, the entire insulating film 97 'is milled at the same milling rate, and the upper surface (junction) of the cap body 95' is exposed, and the insulating film 97 'is removed by milling until a part thereof protrudes from the insulating film 97'. I do. As a result, the cap body 95 is caught, that is, the top is exposed, and a part thereof is protruded from the upper surface of the insulating film 97. In this case, the insulating film 97 ′ is not removed to the bottom of the cap body 95. That is, as shown in FIG. 9F, the insulating film 97 'is removed so that the depth c downward from the upper surface of the insulating film 97 of the cap body 95 becomes larger than zero (c> 0). This c is generally several to several tens of degrees or more.
[0102]
Next, as shown in FIG. 3G, an upper electrode film 98 also serving as a magnetic shield film is formed on the insulating film 97 and the cap body 95 by a dry thin film forming method such as a sputtering method.
[0103]
In the present embodiment, since the cap body 95 and the upper electrode film 98 are formed of the same material, the cap body 95 can be regarded as a part of the upper electrode film 98, and the read gap width is set to the gap film 92 and the MR film. It can be defined as the total thickness of the stacked body 93 and the gap film 94. As a result, the read gap width can be strictly defined, so that deterioration of the magnetic characteristics can be prevented. Further, since the read gap width is the total thickness of the gap film 92, the MR stack 93, and the gap film 94, a narrower read gap can be achieved.
[0104]
The cap body 95 is effective even if it is made of a conductive ferromagnetic material having a small coercive force and a material different from that of the upper electrode film 98. For example, in addition to NiFe, an alloy in which tantalum, zirconium, hafnium, or the like is mixed based on iron, nickel, or cobalt, a sendust-based alloy in which aluminum or silicon is doped, nitrogen, boron, carbon, or the like is added in addition to NiFe. Alloys of the following series. However, it is important to use a material having an etching rate lower than the etching rate of the insulating film 97 ′ when the cap 95 ′ is caught. This is because if the etching rate of the insulating film 97 'is lower, as soon as the cap body 95' is exposed, the etching of the cap body may proceed, and a desired shape may not be obtained.
[0105]
In the present embodiment, an insulating film 97 ″ is stacked on the MR stack 93, the cap body 95 ′, and the lower electrode film 91, and the insulating film 97 ″ is formed until at least the upper surface of the cap body 95 ′ is exposed. Since the MR laminate 93, the cap body 95, and the insulating film 97 around the MR laminate 93 are formed by selective etching and cue milling, an ordinary straight resist pattern or hard mask having no reverse taper should be used. Therefore, it is possible to form a finer MR laminated body than in the case of forming using a lift-off method. In addition, since the cap body 95 is used as a hard mask when the MR laminate 93 is milled, RIE or the like that can reduce the occurrence of tailing can be utilized, and greatly contributes to the improvement of the shape of the MR laminate 93. be able to. Further, since burrs and overlaps of the insulating film 97 cannot occur and the track width can be more strictly defined, an MR element having a track width of 200 nm or less can be easily manufactured.
[0106]
In addition, in the present embodiment, the insulating film 97 ′ is not flattened by CMP or the like until the cap body 95 ′ is exposed, but the insulating film 97 ′ is not flattened until a part of the cap body 95 ′ projects from the insulating film 97 ′. Since the insulating film 97 'can be removed uniformly by milling the 97', the upper and lower electrode films 98 and 91 can be arranged in parallel with each other. Further, since the insulating film 97 'can be uniformly removed over the entire surface of the wafer, a highly accurate element having no variation can be efficiently manufactured. In addition, since the insulating film 97 'is removed so that a part of the cap body 95' protrudes from the insulating film 97 ', the margin for removing the insulating film is greater than when the cap body and the insulating film are flattened. Since it can be made large, production can be facilitated also in that sense.
[0107]
FIG. 10 is a sectional view showing a partial step of forming a TMR head or a GMR head having a CPP structure as still another embodiment of the present invention.
[0108]
First, as shown in FIG. 1A, a lower electrode film 101 also serving as a magnetic shield film, a gap film 102 'made of a nonmagnetic conductive material, and an MR multilayer are formed on an insulating film 100 formed on a substrate (not shown). A film 103 'and a gap film 104' made of a non-magnetic conductive material are sequentially laminated by being formed using a dry thin film formation method, and a photoresist trench pattern 106 is formed thereon. The dry thin film formation method is a vacuum thin film formation method including an evaporation method, a sputtering method, a CVD method, and the like.
[0109]
The photoresist trench pattern 106 transfers a mask pattern to the photoresist layer by applying a photoresist material by a spin coating method or the like, heating as necessary, and exposing the photoresist layer through a mask. Next, after heating if necessary, it can be obtained by washing with developing water. The photoresist trench pattern 106 thus formed may be reduced in width by using a chemical narrowing method or the like.
[0110]
Next, as shown in FIG. 2B, a lower electrode film 101, a gap film 102 'made of a nonmagnetic conductive material, an MR multilayer film 103', and a gap film 104 'made of a nonmagnetic conductive material are used as electrode films. Frame plating is performed using the photoresist trench pattern 106 as a mask to form a cap body 105 '.
[0111]
In this embodiment, the cap body 105 'is formed of the same material as the upper electrode film 108 described later, for example, NiFe (permalloy).
[0112]
Next, as shown in FIG. 3C, the photoresist trench pattern 106 is peeled off using an organic solvent such as acetone to form a cap body 105 'serving as a hard mask. The cap body 105 ′ may be subjected to dry etching such as ion milling in an oblique direction to perform a slimming process to narrow the width.
[0113]
Then, the gap film 102 ′, the MR multilayer film 103 ′, and the gap film 104 ′ are patterned by performing milling or RIE using the hard mask, and as shown in FIG. And a gap film 104 is obtained.
[0114]
The MR laminated body 103 includes a TMR laminated body, a GMR laminated body having a CPP structure, a TMR laminated body including a bias layer for defining a magnetization direction with respect to a free layer, a GMR laminated body having a CPP structure, and an antiferromagnetically coupled magnetic multilayer film. For example, a GMR laminate having a CPP structure, a GMR laminate having a CPP structure having a specular spin-valve magnetic multilayer film, a GMR laminate having a CPP structure having a dual spin valve magnetic multilayer film, or the like.
[0115]
Next, as shown in FIG. 4E, the junction portion, which is the upper surface portion of the MR laminate 103 and the cap body 105 ', is made of, for example, Al ₂ O ₃ Or SiO ₂ Is formed on the entire surface by a dry thin film forming method such as a sputtering method. The insulating film 107 ″ is formed such that the convex protrusion height b is larger than the height a of the cap body 105 ′. A magnetic domain control film and an insulating film may be stacked over the insulating film 107 ''.
[0116]
Thereafter, as shown in FIG. 2F, the upper portion of the convex junction of the insulating film 107 '' is removed by selective etching using high bias RIE. This selective removal is performed until the protruding height b of the insulating film 107 'becomes smaller than the height a of the cap body 105' (b <a).
[0117]
Next, the entire insulating film 107 'is milled at the same milling rate, and the upper surface (junction) of the cap body 105' is exposed, and the insulating film 107 'is removed by milling until a part thereof protrudes from the insulating film 107'. I do. As a result, the cap 105 is caught, that is, the top is exposed, and a part of the cap 105 is protruded from the upper surface of the insulating film 107. In this case, the insulating film 107 ′ is not removed to the bottom of the cap body 105. That is, as shown in FIG. 9G, the insulating film 107 'is removed so that the depth c of the cap body 105 from the upper surface of the insulating film 107 downward becomes greater than zero (c> 0). This c is generally several to several tens of degrees or more.
[0118]
Next, as shown in FIG. 2H, an upper electrode film 108 also serving as a magnetic shield film is formed on the insulating film 107 and the cap body 105 by a dry thin film forming method such as a sputtering method.
[0119]
In the present embodiment, since the cap body 105 and the upper electrode film 108 are formed of the same material, the cap body 105 can be regarded as a part of the upper electrode film 108, and the read gap width is set to the gap film 102 and the MR film. It can be defined as the total thickness of the stack 103 and the gap film 104. As a result, the read gap width can be strictly defined, so that deterioration of the magnetic characteristics can be prevented. Furthermore, since the read gap width is the total thickness of the gap film 102, the MR stack 103, and the gap film 104, a narrower read gap can be achieved. In particular, in the present embodiment, since the cap body 105 is formed by the frame plating method, a narrower lead gap can be easily achieved, and the manufacturing process can be simplified.
[0120]
Note that, as long as the cap body 105 is a ferromagnetic material having conductivity and a small coercive force, a material different from that of the upper electrode film 108 is effective. For example, in addition to NiFe, an alloy in which tantalum, zirconium, hafnium, or the like is mixed based on iron, nickel, or cobalt, a sendust-based alloy in which aluminum or silicon is doped, nitrogen, boron, carbon, or the like is added in addition to NiFe. Alloys of the following series. However, it is important to use a material having an etching rate lower than the etching rate of the insulating film 107 'when performing cueing of the cap body 105'. This is because if the etching rate of the insulating film 107 ′ is lower, as soon as the cap body 105 ′ is exposed, the etching of the cap body may proceed, and a desired shape may not be obtained.
[0121]
In the present embodiment, an insulating film 107 ″ is stacked on the MR multilayer 103, the cap 105 ′, and the lower electrode film 101, and the insulating film 107 ″ is formed until at least the upper surface of the cap 105 ′ is exposed. Since the MR laminate 103, the cap body 105, and the insulating film 107 around the MR laminate 103 are formed by selective etching and cue milling, an ordinary straight resist pattern or hard mask having no reverse taper should be used. Therefore, it is possible to form a finer MR laminated body than in the case of forming using a lift-off method. In addition, since the cap body 105 is used as a hard mask when the MR laminate 103 is milled, RIE or the like that can reduce the occurrence of tailing can be utilized, and greatly contributes to the improvement of the shape of the MR laminate 103. be able to. Furthermore, no burr or overlap of the insulating film 107 can occur, and a more strict definition of the track width is possible, so that an MR element having a track width of 200 nm or less can be easily manufactured.
[0122]
In addition, in the present embodiment, the insulating film 107 'is not flattened by CMP or the like until the cap body 105' is exposed, but the insulating film 107 'is not flattened until a part of the cap body 105' protrudes from the insulating film 107 '. Since the insulating film 107 'can be uniformly removed because the 107' is removed by milling, the upper and lower electrode films 108 and 101 can be arranged in parallel with each other. Further, since the insulating film 107 'can be uniformly removed over the entire surface of the wafer, a highly accurate device having no variation can be efficiently manufactured. In addition, since the insulating film 107 'is removed so that a part of the cap body 105' protrudes from the insulating film 107 ', the margin for removing the insulating film is greater than when the cap body and the insulating film are flattened. Since it can be made large, production can be facilitated also in that sense.
[0123]
The embodiments described above are merely examples of the present invention and are not intended to limit the present invention, and the present invention can be embodied in other various modifications and alterations. Therefore, the scope of the present invention should be defined only by the appended claims and their equivalents.
[0124]
【The invention's effect】
As described above in detail, according to the present invention, a cap body made of a low coercivity ferromagnetic material having conductivity is formed on an MR stack, and an insulating film is stacked thereover and on a lower electrode film. The cap body is regarded as a part of the upper electrode film by removing the insulating film laminated until at least a part of the body protrudes above the insulating film and forming the upper electrode film on the removed insulating film and the cap body. And the read gap width can be determined by the thickness of the MR stack. Since the read gap width can be strictly defined in this way, it is possible to prevent the magnetic properties from deteriorating. Further, since the lead gap width is determined by the thickness of the MR laminate, a narrower read gap can be achieved.
[0125]
In particular, in the present invention, the insulating film is not planarized by CMP or the like until the cap body is exposed, but only a cueing process for removing the insulating film until a part of the cap body protrudes from the insulating film is performed. Therefore, since the insulating film can be removed uniformly, the upper and lower electrode films can be arranged in parallel with each other. In addition, since the insulating film can be uniformly removed over the entire surface of the wafer, a highly accurate element having no variation can be efficiently manufactured. Moreover, since the insulating film is removed so that a part of the cap body protrudes from the insulating film, a margin for removing the insulating film can be larger than when the cap body and the insulating film are flattened. Thus, the production can be facilitated.
[0126]
Furthermore, according to such a manufacturing method, generation of burrs, overlaps, and the like of the insulating film cannot occur, and a more strict definition of the track width becomes possible. Therefore, the track width is 200 nm or less, and the track width is 200 nm or less. An MR element in which current flows in one direction can be easily manufactured.
[0127]
If the cap body is used as a hard mask, it is possible to use RIE for patterning that can suppress the spread of the MR stack.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a partial step of forming a GMR head having a CPP structure by a lift-off method.
FIG. 2 is a sectional view showing a partial step of forming a GMR head having a CPP structure by a contact hole method.
FIG. 3 is a cross-sectional view for explaining a problem of a conventional technique in an MR head having a CPP structure.
FIG. 4 is a sectional view showing a partial step of forming a TMR head or a GMR head having a CPP structure as one embodiment of the present invention.
5 is a sectional view schematically showing an example of a layer structure of a TMR head formed according to the embodiment of FIG.
FIG. 6 is a sectional view schematically showing another example of the layer structure of the TMR head formed according to the embodiment of FIG. 4;
FIG. 7 is a cross-sectional view showing a partial process of forming a TMR head or a GMR head having a CPP structure as another embodiment of the present invention.
FIG. 8 is a cross-sectional view showing a partial step of forming a TMR head or a GMR head having a CPP structure as still another embodiment of the present invention.
FIG. 9 is a cross-sectional view showing a partial step of forming a TMR head or a GMR head having a CPP structure as still another embodiment of the present invention.
FIG. 10 is a cross-sectional view showing a partial step of forming a TMR head or a GMR head having a CPP structure as still another embodiment of the present invention.
[Explanation of symbols]
10, 14, 14 ', 20, 24, 24', 34, 47, 47 ', 47 ", 77, 77', 77", 87, 87 ', 87 ", 97, 97', 97 '', 107, 107', 107 '' insulating film
11, 21, 31, 41, 71, 81, 91, 101 Lower electrode film
12, 22, 43, 73, 83, 93, 103 MR laminated body
12 ', 22', 32, 43 ', 73', 83 ', 93', 103 'MR multilayer
13,23,26,46,76,86 Photoresist pattern
13a base
15, 25, 35, 35 ', 35 ", 48, 78, 88, 98, 108 Upper electrode film
24a contact hole
26a opening
33, 33 ', 33 ", 45, 75, 85, 95, 105 Cap body
40, 70, 80, 90, 100 substrate
42, 42 ', 44, 44', 72, 72 ', 74, 74', 82, 82 ', 84, 84', 92, 92 ', 94, 94', 102, 102 ', 104, 104' Gap film
43a Underlayer
43b pin layer
43c pinned layer
43d Tunnel barrier layer
43e free layer
43f non-magnetic metal layer
43g antiferromagnetic layer
45 ', 45 ", 75', 75", 85 ', 85 ", 95', 95", 105 'Cap film
96, 106 Photoresist trench pattern

Claims (14)

A magnetoresistive effect laminate on which a current flows in a direction perpendicular to the lamination surface to extract output on the lower electrode film, and a cap body made of a conductive low coercive force ferromagnetic material laminated on the magnetoresistive effect laminate Forming an insulating film on the formed cap body and the lower electrode film, removing the laminated insulating film until at least a portion of the cap body protrudes above the laminated insulating film, Forming a top electrode film on the removed insulating film and the cap body. A magnetoresistive multilayer is laminated on the lower electrode film, a cap film of a low coercivity ferromagnetic material having conductivity is laminated on the magnetoresistive multilayer, and a mask is formed on the laminated cap film. Forming the cap body by patterning the cap film, and then patterning the magnetoresistive multilayer film using the cap body as a hard mask, thereby forming the magnetoresistive laminate. The manufacturing method according to claim 1, wherein After laminating a magnetoresistive multilayer on the lower electrode film, laminating a cap film of a low coercivity ferromagnetic material having conductivity on the magnetoresistive multilayer, a mask is formed on the laminated cap film. The method according to claim 1, wherein the cap body and the magnetoresistive laminate are formed by forming and patterning the cap film and the magnetoresistive multilayer film. A magnetoresistive multilayer is laminated on the lower electrode film, a resist trench pattern is formed on the magnetoresistive multilayer, and a low coercivity ferromagnetic material having conductivity through the formed resist trench pattern. After forming the cap film, the resist trench pattern is removed to form the cap body, and the magnetoresistive effect multilayer is patterned by patterning the magnetoresistive multilayer film using the cap body as a hard mask. The method according to claim 1, wherein a body is formed. The method according to claim 4, wherein the cap film is formed by a dry thin film formation method. The method according to claim 4, wherein the cap film is formed by a frame plating method. The removal of the insulating film selectively removed the insulating film on the cap body until the protrusion height (b) of the insulating film on the cap body became smaller than the height (a) of the cap body. The method according to any one of claims 1 to 6, further comprising removing the entire insulating film until at least a part of the cap body protrudes above the insulating film. 8. The method according to claim 1, wherein the removal of the insulating film is performed by etching, and an etching rate of the cap body in the etching is lower than an etching rate of the insulating film. The method according to any one of claims 1 to 8, wherein the insulating film is removed so that a part of the cap body projects from a lower surface of the upper electrode film. A non-magnetic conductive gap film is laminated between the lower electrode film and the magnetoresistive effect laminate, and a non-magnetic conductive gap film is laminated between the magnetoresistive effect laminate and the cap body. The method according to any one of claims 1 to 9, wherein: The method according to any one of claims 1 to 10, wherein the magnetoresistive laminate is a tunnel magnetoresistive laminate. The method according to any one of claims 1 to 10, wherein the magnetoresistive laminate is a giant magnetoresistive laminate of a vertical current passing type. The method according to any one of claims 1 to 10, wherein the magnetoresistive stack is a tunnel magnetoresistive stack including a bias layer for defining a magnetization direction with respect to a free layer. 11. The giant magnetoresistive laminate of the vertical direction passing current including a bias layer for defining a magnetization direction with respect to a free layer, wherein the magnetoresistive laminate is any one of claims 1 to 10. The manufacturing method as described.

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