JP3164736B2 - Thin film magnetic head - 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 provided in a floating magnetic head for a hard disk drive and exhibiting a reproducing function, and more particularly to a hard bias type thin-film magnetic head.

[0002]

2. Description of the Related Art FIG. 10 is an enlarged front view (cross-sectional view) of a conventional thin film magnetic head of a hard bias type as viewed from a recording medium side. In this thin-film magnetic head, a lower insulating layer 1 of Al ₂ O ₃ or the like is laminated on a lower shield layer of permalloy or the like, and a head element laminate 2 is provided on the lower insulating layer 1. The head element laminate 2 includes a soft magnetic (SAL) layer 3, a nonmagnetic (SHUNT) layer 4, and a magnetoresistive (MR) layer 5, which are laminated in this order from the lower insulating layer 1 side. Further, an upper insulating layer 6 such as Al ₂ O ₃ and an upper shield layer such as permalloy are formed thereon. On both sides of the head element laminate 2 in the track width direction (x direction), the hard bias layer 7 and the lead layer 8 are laminated in this order from the lower insulating layer 1 side. The hard bias layer 7 is connected and connected to both ends of the magnetoresistive layer 5 in the track width direction.

In this thin-film magnetic head, the hard bias layer 7 functions as a magnet magnetized in the x direction, and the longitudinal magnetic field applied from the hard bias layer 7 to the magnetoresistive layer 5 causes the magnetoresistive layer 5 to move in the x direction. It is magnetized and becomes a single magnetic domain. The detection current is supplied to the magnetoresistive layer 5 through the lead layer 8 and the hard bias layer 7, and is applied to the magnetoresistive layer 5 by the magnetostatic coupling energy provided by the soft magnetic layer 3 when the detection current flows through the magnetoresistive layer 5. On the other hand, a lateral bias magnetic field is applied in the y direction, whereby the resistance change with respect to the magnetic field change of the magnetoresistive layer 5 is set to have a linear state. In the reproducing operation, the recording medium faces in the direction facing the paper surface of FIG. 10, and the relative movement direction between the magnetic head and the recording medium is the z direction. When the magnetic head moves relative to the recording medium, the resistance value of the magnetoresistive layer 5 changes due to the magnetoresistive effect (HR effect) of the magnetoresistive layer 5,
This is detected as a change in the voltage of the detection current.

[0004]

The characteristics required for the hard bias layer 7 of the magnetic head are as follows. (1) Barkhausen noise can be reduced by making the magnetoresistive layer 5 a single magnetic domain in the x direction with high precision. However, in order to make the magnetoresistive layer 5 a single magnetic domain with high precision, the hard bias layer 7 must be maintained. It is necessary to use a material having excellent magnetic properties such as high values of the magnetic force Hc and the saturation magnetization Bs. (2) A lead layer 8 is formed on the hard bias layer 7 as an upper ground layer, and a base layer is formed below the hard bias layer 7 as necessary. The coercive force Hc of the hard bias layer 7 may be affected by the interface of the formation layer. Therefore, it is necessary to appropriately select a combination of the material of the hard bias layer 7 and the materials of the upper and lower layers.

(3) The thickness of the hard bias layer 7 affects the coercive force Hc of the hard bias layer 7 and the squareness of the BH loop. This will affect the coercive force and the like. Therefore, it is necessary that the material of the hard bias layer 7 and the upper layer and the lower layer be made of a material that satisfies the conditions (1) to (3).

[0006] The present invention is to solve the above problems,
A thin-film magnetic head that optimizes the magnetic properties of the hard bias layer and reduces Barkhausen noise by optimizing the material of the hard bias layer, and further optimizing the thickness of the hard bias layer and the thickness of the underlayer. The purpose is to provide.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a magnetoresistive layer.
When, in the above thin film magnetic head having a hard bias layer connected to both sides of the track width direction of the magnetoresistive layer, the hard bias layer is formed of a magnetic film of Co _x -Cr _y -Ta _z, x = 76 to 92 at%, y
= 4 to 24 at%, z = 0 to 16 at% (x + y
+ Z = 100) .

Further, x = 80-90 at%, y = 10
２０20 at%, z = 0 to 10 at% (however, x + y + z
= 100).

Further, the magnetic film of the Co _x -Cr _y -Ta _z
Preferably has a thickness of 50 to 600 angstroms.
Preferred, more preferably, the Co _x -Cr _y -Ta _z
The thickness of the magnetic film is 50 to 1000 angstroms.
You.

Further, the magnetic film of the Co _x -Cr _y -Ta _z
Film as an underlayer of the hard bias layer formed by
A Cr film with a thickness of 10 Å or more must be provided.
Is preferred.

Further, the magnetic film of the Co _x -Cr _y -Ta _z
As the upper layer of the hard bias layer formed by
The magnetoresistive layer is provided with a Cr film for applying a detection current.
Preferably.

[0012]

According to the present invention, the hard bias layer is made of Co-Cr.
It is characterized by using a magnetic film of -Ta. This Co—Cr—Ta magnetic film has a high coercive force and a high saturation magnetization, has an appropriate BH loop squareness ratio, and has an excellent bias function for making the magnetoresistive layer a single magnetic domain. ing. In particular, since the variation in coercive force and saturation magnetization due to temperature change is small, it becomes suitable as a hard bias layer of a thin film head exposed to a high temperature environment during manufacture or use.

Further, it is appropriate to provide a Cr film as an underlayer and an upper layer of the hard bias layer formed of the Co—Cr—Ta magnetic film. When the upper layer is a Cr film, its thickness dimension hardly affects magnetic properties such as the coercive force of the hard bias layer. Further, the influence on the magnetic properties of the hard bias layer can be made very small by setting the thickness of the Cr film as the underlayer to 10 Å or more, more preferably 50 Å or more.

Co-Cr-T serving as a hard bias layer
The composition ratio of a is x: y: z of atomic% and x = 76-9.
2, y = 4 to 24, z = 0 to 16 (where x + y + z =
100), and in this case, the coercive force Hc
Is 200 Oe or more, and the saturation magnetization is 4 Kg or more. In addition, Co-Cr-T
In the case where the magnetic film a has this composition ratio, the film thickness is 50 to 600
By setting it in the angstrom range, 200
The coercive force Hc of (Oe) or more can be secured.

A more preferable range of the composition ratio of Co—Cr—Ta is x: y: z in atomic%, and x = 80-9.
0, y = 10 to 20, z = 0 to 10 (x + y + z
= 100). In this case, the coercive force Hc of the hard bias layer can be set to 500 (Oe) or more, and the saturation magnetization Bs can be set to 6 (kG) or more. In addition, Co-
With a Cr-Ta magnetic film, the coercive force Hc can be made 500 (Oe) or more when the film thickness is in the range of 50 to 1000 angstroms.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an enlarged front view (cross-sectional view) of the thin-film magnetic head of the present invention as viewed from a surface facing a recording medium. This thin-film magnetic head is used, for example, by being provided on the trailing side end face of a floating magnetic head used in a hard disk drive. This magnetic head functions as a reproducing head. In the case of a recording / reproducing head, a recording magnetic head portion is formed as a thin film on the upper shield layer of the thin film magnetic head shown in FIG. The recording surface of a recording medium such as a hard disk faces the magnetic head in a direction parallel to the paper of FIG. The x direction is the track width direction, and the z direction is the relative movement direction of the magnetic head with respect to the recording medium.

The lower shield layer is made of permalloy or the like, on which a lower insulating layer 1 of an Al ₂ O ₃ film is formed, and a head element laminate 2 is provided on the lower insulating layer 1. The head element laminate 2 is formed by sequentially laminating a soft magnetic (SAL) layer 3, a nonmagnetic (SHUNT) layer 4, and a magnetoresistive (MR) layer 5 from the lower insulating layer 1 side. For example, the soft magnetic layer 3 is a 250-Å-thick Fe—Ni—Nb-based material film, the non-magnetic layer 4 is a 200-Å-thick Ta film, and the magnetoresistive layer 5 is a 300-Å-thick Fe—Ni-based material film. It is.

On both sides of the head element laminate 2 in the track width direction (x direction), an underlayer 1
1, a 200 angstrom thick Cr film is formed, and a 600 angstrom thick Co—Cr—Ta magnetic film 12 is formed thereon as a hard bias layer 12. On the hard bias layer 12, the upper ground layer 13
Is formed as a Cr film having a thickness of 300 Å. The upper layer 13 functions as a lead layer, and the detected current is transmitted from the upper layer 13 to the hard bias layer 1.
2 to the magnetoresistive layer 5. Note that another conductive material may be laminated on the upper layer 13 as a lead layer.

The surfaces of the magnetoresistive layer 5 and the upper layer 13 are
An upper insulating layer 6 made of Al ₂ O ₃ is formed, and a permalloy upper shield layer is further formed thereon. The hard bias layer 12 is magnetized in the x direction, a longitudinal bias magnetic field in the x direction is applied to the magnetoresistive layer 5 from the hard bias layer 12, and the magnetoresistive layer 5 is magnetized in the x direction to form a single magnetic domain. Is done. In order to apply a sufficient longitudinal bias magnetic field to the magnetoresistive layer 5 by the hard bias layer 12, it is necessary that the hard bias layer 12 can obtain high coercive force and residual magnetization.

FIG. 2 shows the magnetic material (hard bias layer) B-
This shows an H loop, where H indicates the magnitude of the external magnetic field, and B indicates the magnitude of the magnetization of the magnetic material (hard bias layer). Hc is the coercive force, Br is the residual magnetization (residual magnetic flux density), and Bs is the saturation magnetization (saturated magnetic flux density). S ^* and S in ^Equation 1 indicate the squareness ratio of the BH loop,
(0 <S ^* <1) and (0 <S <1).

[0021]

(Equation 1)

The residual magnetization of the hard bias layer 12 is Br,
Assuming that the thickness of the hard bias layer is δ1, the saturation magnetization of the magnetoresistive layer 5 is Bs ′, and the thickness of the magnetoresistive layer 5 is δ2, the relationship is expressed by Equation 2. In Equation 2, A is a constant.

[0023]

(Equation 2)

From equation (2), the hard bias layer needs to have a high residual magnetization Br. Therefore, it is preferable that the hard bias layer has a high saturation magnetization Bs and a squareness ratio S close to 1. Further, the hard bias layer needs to have a high coercive force Hc, and therefore, it is preferable that S ^* is close to 1.

FIG. 3 shows a coercive force Hc (Oe), a saturation magnetization Bs (T; Tesla), and a residual magnetization Br (T) in the BH loop of the Co—Cr—Ta magnetic film used as the hard bias layer 12. , And squareness ratios S ^* and S. Magnetic film used for the measurement of the B-H loop characteristic shown in FIG. 3 is a Co _x -Cr _y -Ta _z, of the composition ratio x:
y: z was 86: 12: 2 in atomic weight%. That is, C
o ₈₆ Cr ₁₂ Ta ₂ was used. A 200 Å thick Cr film was formed as a base layer on a glass substrate, and a Co ₈₆ Cr ₁₂ Ta ₂ film was formed thereon to a thickness of 600 Å, and the BH loop was measured.

The result shown in FIG.
From 260 ° C. to 260 ° C. for 5 minutes in a temperature stepwise changing every 20 ° C., and the Co ₈₆ Cr ₁₂ Ta ₂ film is ± 10 (k
The BH loop was measured by applying the magnetic flux G). In the measurement results of FIG. 3, a value close S ^* 1, moreover S ^* it can be seen that not affected at all by temperature. The magnitude of the saturation magnetization Bs and the magnitude of the residual magnetization Br are generally high values, and their decrease is small even in a high-temperature environment. Further, the coercive force Hc decreases at high temperatures, but still shows a high value of 300 (Oe) or more in a high-temperature environment of 260 ° C.

Thus, the magnetic film of Co—Cr—Ta is
It can be seen that Bs, Br and Hc are high values, and S ^* is close to 1, which is suitable as a material for the hard bias layer. Also, in the thin film magnetic head, when used in the manufacturing process and hard disk device, etc.,
Although it is often placed in a high temperature environment, FIG.
It can be seen that the magnetic properties of the -Cr-Ta magnetic film are not extremely deteriorated even in a high temperature environment, and there is no problem in use as a hard bias layer.

Next, FIG. 4 shows the composition ratio of Co _x -Cr _y -Ta _z film used as the hard bias layer 12, the relationship between the magnitude of the coercive force Hc and saturation magnetization Bs. The base of the triangle in FIG. 4 is the atomic weight% (at%) of Co.
That is, x is shown, and the right side shows y of the atomic weight% of Cr,
The left side shows z of the atomic weight% of Ta. Further, the coercive force Hc is indicated by a dashed line, and the magnitude of the saturation magnetization Bs is indicated by a dashed line. x is not less than 76 and not more than 92 (76 to 9
2) A region having a composition ratio where y is 4 or more and 24 or less (4 to 24) and z is 16 or less (0 to 16) is defined as (A). However _{Co x -Cr y -Ta x + y} + z in the _z always 100
It is. Co-Cr having a composition ratio in this region (a)
In -Ta, the coercive force Hc is 200 (Oe) or more and the saturation magnetization Bs is 4 (kG) or more.

When x is 80 or more and 90 or less (80 to 9)
0), y is 10 or more and 20 or less (10 to 20), z is 1
A region having a composition ratio of 0 or less (0 to 10) is defined as (b). Similarly x + y + z in the Co _x -Cr _y -Ta _z is always 100. Co having a composition ratio in this region (b)
In -Cr-Ta, the coercive force Hc is 500 (Oe) or more, and the saturation magnetization Bs is almost 6 (kG) or more. Hard bias layer 12 for applying a longitudinal bias magnetic field to magnetoresistive layer 5
Is sufficient for practical use if the coercive force Hc is 200 (Oe) or more and the saturation magnetization Bs is 4 (kG) or more, and the magnetic resistance layer 5 is made into a single magnetic domain in the x-direction to obtain Barkhausen noise. Effect can be sufficiently exhibited. When the coercive force Hc is 500 (Oe) or more and the saturation magnetization Bs is 6
Above (kG), the magnetic domain of the magnetoresistive layer 5 can be formed into a single magnetic domain in the x direction with extremely high accuracy, which is extremely effective in reducing Barkhausen noise.

[0030] Thus, the Co _x -Cr _y -Ta _z used as a hard bias layer 12, the composition ratio is atomic weight%
And x is 76 or more and 92 or less (76 to 92), y is 4 or more and 24 or less (4 to 24), and z is 16 or less (0 to 16). More preferably, x is 80 or more and 90 or less. (80-90), y is 10 or more and 20 or less (10-2
0) and z are 10 or less (0 to 10).

Next, the magnetic characteristics of the hard bias layer 12 change depending on its thickness. 5 and 6 show Co-
It shows the relationship between the thickness of the magnetic film of Cr-Ta and the magnetic properties. In FIG. 5, the horizontal axis represents the thickness of the Co—Cr—Ta film (in Angstroms), and the vertical axis represents Co—Cr—Ta.
The graph shows the coercive force Hc (Oe) of the -Ta film and the squareness ratios S * and S of the BH loop. FIG. 6 shows Co on the horizontal axis.
-The thickness of the Cr-Ta film is taken, and the vertical axis represents the saturation magnetization Bs (k
G).

The lines α1 to α4 shown in FIG. 5 and FIG.
7 is a characteristic line relating to Co—Cr—Ta of the composition ratio in the region (b) shown in FIG. The measured film has a composition ratio indicated by α in FIG. 4 and is Co ₈₆ in which x is 86, y is 12, and z is 2.
Cr is a ₁₂ Ta ₂ film. On a glass substrate, a Cr film was formed as a base layer with a thickness of 200 angstroms, and a Co ₈₆ Cr ₁₂ Ta ₂ film was formed thereon by changing the film thickness. The characteristics of the BH loop were examined by applying a magnetic flux of (kG). α
1 is the coercive force Hc, α2 is the squareness ratio S ^* , α3 is the squareness ratio S,
α4 is the saturation magnetization Bs.

Co ₈₆ C, which is the composition ratio of α in the region (b)
At r ₁₂ Ta ₂ , as shown in FIG. 6, the saturation magnetization Bs hardly changes due to the change in the film thickness. As shown in FIG. 5, the coercive force Hc gradually decreases as the film thickness increases. However, when the film thickness is 600 Å, the coercive force Hc is 600 (Oe) and the film thickness is 10 (Oe).
At the time of 00 angstrom, the coercive force Hc is 500 (O
e), which is always a high value. The squareness ratio S ^* Contact and <br/> S are both in thickness 200 angstroms 0.
It becomes close to 1 when it is 8 or more. When the film thickness is 50 angstroms, S ^* is about 0.9 and S is about 0.7. 5 and 6, Co ₈₆ Cr ₁₂ Ta in the region (b)
_It can be seen that the _two films can exhibit sufficient magnetic characteristics regardless of the film thickness. However, the thickness of the hard bias layer is required to be at least 50 Å or more due to the relationship with the thickness of each layer of the thin film magnetic head. And the structural balance between them is lost. In addition, from FIG. 5, when the film thickness is less than 50 angstroms, the squareness ratio S becomes too low. From above
When the hard bias layer 12 is formed of a Co—Cr—Ta film having the composition ratio of the region (b) , the thickness is 50
It is preferable that the thickness be greater than or equal to Å and less than or equal to 1000 Å.

Next, the line indicated by β in FIG.
The relationship between the film thickness and the coercive force Hc of the Co—Cr—Ta film having the composition ratio in the region (a) is shown. The measurement was performed by forming a 200 Å Cr film on a glass substrate, forming a Co—Cr—Ta film on the Cr film by changing the film thickness, and ± 1.
The BH loop is measured by applying a magnetic flux of 0 (kG). The composition ratio of the film is indicated by β in FIG. 4, where x is 92, y is 6, z is 2, and Co ₉₂ Cr ₆ T
a ₂ film. In this film, similarly to α1, the coercive force Hc decreases as the film thickness increases, and the coercive force Hc is 200 (Oe) at a film thickness of 600 Å. It is necessary that the hard bias layer 12, the coercive force Hc is 200 (Oe) or more, thus Co-C composition in the region of (b)
When an r-Ta film is used as a hard bias layer, the film thickness is preferably not less than 50 Å and not more than 600 Å. However, the coercive force of the magnetic film can be adjusted by a film forming method, an annealing process, and the like, and the coercive force is adjusted even for a film such as Co ₉₂ Cr ₆ Ta ₂ in the region (a). Thus, it is possible to use even a film having a thickness of about 1000 Å.

FIGS. 7 and 8 show the relationship between the thickness of the Cr film serving as the underlayer and the magnetic characteristics of the Co—Cr—Ta film. A Cr film serving as an underlayer is formed on a glass substrate by changing the film thickness, and a Co ₈₆ Cr ₁₂ Ta ₂ film having a composition ratio of the region (b) is formed thereon.
The BH loop characteristics (with an externally applied magnetic flux of ± 10 kG) were measured for the r film. 7 and 8
It can be seen that the saturation magnetization Bs and the squareness ratios S ^* and S hardly change even when the thickness of the Cr film serving as the underlayer changes, and the Cr film is suitable as the underlayer of the Co—Cr—Ta film. I understand that there is.

However, the coercive force Hc of the Co—Cr—Ta layer decreases as the thickness of the Cr film of the underlayer decreases. This is because when the thickness of the underlayer becomes thin and the crystal orientation of the underlayer becomes unstable, the crystal structure of the Co—Cr—Ta layer is affected by the underlayer at the interface with the underlayer Cr layer, and −
It is considered that the crystal orientation of the Cr-Ta film slightly changed and the coercive force in the magnetization direction (x direction) was affected. FIG.
The curve shows that the coercive force Hc decreases when the thickness of the Cr film of the underlayer falls below 50 angstroms. However, this is because the Cr film is 5
It is difficult to form a film thinner than 0 Å, and if the film thickness is smaller than 50 Å, C
The film thickness of r is 0, and the measured value of 50 angstroms and the measured value of 0 are connected by a line, resulting in a curve shown in FIG.

Therefore, in practice, the formation of the Cr film as the underlayer can increase the coercive force Hc of the Co—Cr—Ta film to a relatively high value. However, the lower limit of the thickness of the Cr film is 10 angstroms due to the film forming conditions, and the thickness of the Cr layer must be at least 50 angstroms or more in relation to the thickness of other films of the thin-film magnetic head. is there. Therefore, the thickness of the Cr film of the underlayer is preferably 10 Å or more, more preferably 50 Å or more. Even if the thickness of the Cr film of the underlayer is large, there is no adverse effect on the magnetic properties of the Co—Cr—Ta film, but considering the structural balance with the thickness of the other layers of the thin-film magnetic head, The upper limit of the thickness of the Cr film is preferably about 600 Å or less.

Next, FIG. 9 shows the result of examining the relationship between the thickness of the Cr film as the upper layer of the Co-Cr-Ta film and the magnetic characteristics of the Co-Cr-Ta layer. As a sample, a Cr film was formed as a base layer on a glass substrate to a thickness of 200 angstroms, and a magnetic layer of Co ₈₆ Cr ₁₂ Ta ₂ was formed thereon to a thickness of 600 angstroms. A BH loop characteristic was examined for each of the Cr films formed and the film thickness of the upper layer changed. In FIG. 9, a black circle and a solid line connecting the black circles are obtained by applying a magnetic flux of ± 10 kG to the three layers formed and examining the BH loop. The BH loop was similarly examined for annealed at 250 ° C. for 2 hours after forming the film. FIG.
In the above, the change in the thickness of the Cr film of the upper layer is caused by Co—Cr—Ta
It can be seen that the magnetic properties of the film are hardly affected. Therefore, it can be seen that when the hard bias layer is a Co—Cr—Ta layer, a Cr film is suitable as the upper layer.

When the Cr film is provided as the upper layer as described above, there is no limitation on the film thickness. However, in order to achieve a structural balance with the film thickness of the other layers of the thin-film magnetic head, the upper layer is formed. It is preferable that the film thickness is about 10 Å or more or 50 Å or more and about 1000 Å or less, about 1500 Å or less, or about 2000 Å or less.

As described above, when the Co—Cr—Ta film is formed as the hard bias layer of the thin film head, the composition ratio is preferably within the region (a) of FIG. 4 and further within the region (b). It is preferable that The underlayer and the upper layer are preferably Cr films. Further, it is preferable that the thickness of the Co—Cr—Ta film and the thicknesses of the underlayer and the upper layer be in the above-described ranges. It should be noted that the thin-film magnetic head of the present invention is not limited to a floating magnetic head, and can be used for other magnetic heads and magnetic detection devices.

[0041]

As described above, in the present invention, by using a Co—Cr—Ta film as the hard bias layer, it is possible to obtain the coercive force Hc and the residual magnetization Br required for the hard bias layer. By applying a sufficient longitudinal bias magnetic field to the magnetoresistive layer, the magnetoresistive layer can be made into a single magnetic domain with high accuracy, and a thin-film magnetic head with extremely low Barkhausen noise can be obtained. When a Cr film is provided as an underlayer and an upper layer of the hard bias layer, the underlayer does not affect the magnetic characteristics of the hard bias layer of the Co—Cr—Ta film.

Further, Co _x -Cr _y -Ta composition ratio of _z x:
By setting y: z: in the region (a), the coercive force Hc and the saturation magnetization Bs can be increased. By setting y: z: in the region (b), the coercive force Hc and the saturation magnetization Bs can be further increased. Can be.

A high coercive force can be obtained by properly setting the thicknesses of the hard bias layer, the underlayer and the upper layer.

[Brief description of the drawings]

FIG. 1 is an enlarged front view (cross-sectional view) showing an embodiment of a thin-film magnetic head according to the present invention;

FIG. 2 is a BH loop diagram of a magnetic film constituting a hard bias layer;

FIG. 3 is a diagram showing the relationship between the temperature of a Co—Cr—Ta film and BH loop characteristics;

FIG. 4 is a diagram showing the relationship between the composition ratio of a Co—Cr—Ta film and coercive force and saturation magnetization.

FIG. 5 is a diagram showing a relationship between a film thickness of a Co—Cr—Ta film and a coercive force;

FIG. 6 is a diagram showing the relationship between the thickness of a Co—Cr—Ta film and saturation magnetization;

FIG. 7 is a diagram showing a relationship between a film thickness of an underlayer and a coercive force of a Co—Cr—Ta film,

FIG. 8 is a diagram showing the relationship between the thickness of an underlayer and the saturation magnetization of a Co—Cr—Ta film;

FIG. 9 is a diagram showing a relationship between a film thickness of an upper layer and a coercive force of a Co—Cr—Ta film,

FIG. 10 is an enlarged front view (cross-sectional view) of a conventional thin-film magnetic head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower insulating layer 2 Head element laminated body 3 Soft magnetic layer 4 Nonmagnetic layer 5 Magnetoresistance layer 6 Upper insulating layer 11 Underlayer 12 Hard bias layer 13 Upper ground layer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G11B 5/39 G11B 5/31

Claims (7)

(57) [Claims] And 1. A magnetoresistive layer, a thin film magnetic head having said magnetoresistive layer hard bias layer connected to both sides of the track width direction of the hard bias layer
Co _x -Cr _y -Ta _z are formed by magnetic film, x = 76~92at%, y = 4~24at%, z = 0~
A thin film magnetic head characterized by 16 at% (x + y + z = 100) . 2. x = 80-90 at% , y = 10-20
at% , z = 0 to 10 at% (where x + y + z = 10
0) A thin film magnetic head according to claim 1, wherein. Wherein the Co _x -Cr _y -Ta _z thin film magnetic head according to claim 1, wherein the thickness of the magnetic film is 50 to 600 Angstroms Wherein said Co _x -Cr _y -Ta _z thin film magnetic head according to claim 2, wherein the thickness of the magnetic film is 50 to 1000 angstroms. Wherein said Co _x -Cr _y -Ta as an underlying layer of hard bias layer formed by the magnetic film of _z, the thin film magnetic head according to any one of 4 to claims 1 Cr film is provided . 6. A film thickness of a Cr film as an underlayer is 10
6. The thin-film magnetic head according to claim 5 , wherein the thickness is equal to or more than Å. 7. The magnetic film of the Co _x -Cr _y -Ta _z
The magnetic bias is formed as an upper layer on the hard bias layer formed by
Check that a Cr film that gives a detection current to the resistance layer is provided.
A thin-film magnetic head according to any one of claims 1 to 6.