JP2009140546A - Method for manufacturing perpendicular recording magnetic head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a fine neck height into a fine and precise shape as designed in a method for manufacturing a perpendicular recording magnetic head.
A first concave portion 3 for embedding a thin rectangular light pole 6 having a width of 50 to 500 nm as a front end portion and a second concave portion 4 for embedding a rear end portion 7 having a large area are embedded. When forming the buried insulating film 2, they are formed by different mask processes.
[Selection] Figure 1

Description

  The present invention relates to a method of manufacturing a perpendicular recording magnetic head, and more particularly to a method of manufacturing a perpendicular recording magnetic head characterized by a configuration for precisely processing the neck height of a write head for perpendicular recording.

  In recent years, hard disk drive devices have been used as storage means in various information processing devices, and perpendicular magnetic heads using a single magnetic pole core have been used as write heads that constitute magnetic heads in such hard disk drive devices. Yes.

Since such a perpendicular recording write head generally needs to process a magnetic material having a high saturation magnetic flux density B _s into a fine and precise shape, the conventional perpendicular recording write will be described with reference to FIG. The configuration of the core main magnetic pole part of the head will be described.

See FIG.
FIG. 12 is a schematic plan view of a core main magnetic pole portion of a conventional perpendicular recording write head, that is, a shape seen from the wafer surface. A core main magnetic pole portion 50 of a recent perpendicular recording write head is made of ABS. A width detail called a rectangular neck height 51 is provided in the vicinity of the (floating surface).
The processing accuracy of the neck height 51 is a very important part that determines the characteristics of the perpendicular recording write head, that is, characteristics such as magnetic flux intensity, write width, and leakage of magnetic flux during writing.

Conventionally, this portion is processed using an exposure mask process in a wafer process.
In particular, it is necessary to accurately form the fine core main magnetic pole portion 50 including the neck height 51 in order to meet the demand for high density recording. However, in the conventional method, when the neck height 51 is finely formed, it is oblique. Although ion milling from the direction is performed to form an inverted trapezoidal shape, there is a problem that the neck height 51 falls when miniaturization progresses.

Therefore, it has been proposed to form a main pole by embedding a ferromagnetic film in the recess after forming a recess for forming the main pole in the Al ₂ O ₃ film as the base insulating film by a photoetching process. (For example, refer to Patent Document 1).
JP 2006-139898 A

  However, with the recent increase in the density of magnetic disk devices, the size of the magnetic disk head has become smaller, and the length of the portion called the neck height is about 200 nm (the width is about 300 nm) in the recent head. Is expected to be even smaller.

  At this time, even if the design as shown in FIG. 10 is employed, since a method of forming a neck height portion and a large rear portion with a single mask as in the prior art is adopted, as a result, the light pole on the ABS surface is obtained. There was a problem with the accuracy of the width.

  In other words, as the neck height becomes shorter, it becomes difficult to process the shape as designed, and the neck height portion becomes a curve instead of a straight line, resulting in a significant obstacle to the control of the core width in the ABS. Therefore, this situation will be described with reference to FIG.

See FIG.
FIG. 13 is an explanatory diagram of problems caused by miniaturization. As shown in the figure, at the corners and bends of the neck height pattern, in the exposure process and the etching process, in particular, in the exposure process, in the processing capability, A straight part forming the neck height is dragged in the large area part to form a curved part, and it is difficult to form a straight line of the edge.
That is, even if the design is shown by a broken line in the figure, the neck height 52 becomes inclined on the actual wafer as the neck height 51 becomes shorter.

  In this way, the fact that a pattern that is faithful as designed is not possible is also a fundamental problem of lithography. As the resolution itself improves, the fidelity will improve, but when forming a light head in the near future, Since the height is particularly short and has become 200 nm or less, this problem has particularly emerged.

  Accordingly, an object of the present invention is to form a fine neck height into a fine and precise shape as designed.

FIG. 1 is a diagram illustrating the basic configuration of the present invention. Means for solving the problems in the present invention will be described with reference to FIG.
To solve the above-described problem, the present invention provides a first concave portion for embedding a thin rectangular light pole 6 having a width of 50 to 500 nm as a tip portion in a method of manufacturing a perpendicular recording magnetic head. 3 and the second concave portion 4 for embedding the rear end portion 7 of a large area are formed in the buried insulating film 2 by separate mask processes.

  In this way, two masks are used, the first one is a mask for forming only the straight portion, that is, the rectangular light pole 6, and the second one is the rear end portion 7 of the large rear area. By using the mask, the straight portion that forms the light pole 6 is not dragged at the rear end 7 of the large area so that a curved portion is not formed, thereby avoiding instability of the shape due to the mask process. be able to.

  In this case, after forming the first recess 3, the second recess 4 is formed, and then the first recess 3 and the second recess 4 are completely filled with the soft magnetic film 5. It is desirable to flatten by polishing, and the first recess 3 can be formed with higher accuracy than the case where the second recess 4 is formed first.

  Further, it is desirable that the second concave portion 4 exposes the surface of the main magnetic pole auxiliary layer 1 provided under the buried insulating film 2, and thereby the rear end portion 7 having a large area and Magnetic coupling with the main magnetic pole auxiliary layer 1 can be maintained.

  In this case, in the step of forming the second recess 4, a part of the main magnetic pole auxiliary layer 1 is dug in the projection overlapped portion with the first recess 3, and the first recess 3 The thick part of the projected overlapping part is absorbed by the main magnetic pole auxiliary layer 1, and the influence of the thick part can be reduced.

  Alternatively, the rear end portion 7 having a large area may also serve as the main magnetic pole auxiliary layer 1, thereby eliminating the need to provide the main magnetic pole auxiliary layer 1 under the buried insulating film 2. It becomes.

  In addition, it is desirable that the depth of the second recess 4 be greater than the depth of the first recess 3, whereby the magnetic flux density from the light pole 6 can be increased.

  In addition, it is desirable that the planar shape of the second concave portion 4 is a rectangle, so that the alignment margin with the linear first concave portion 3 becomes very large, thereby simplifying the manufacturing process. At the same time, the production yield is improved.

  According to the present invention, the plane shape of the light pole of the main magnetic pole is not rounded or slanted as in the past, and a beautiful straight line as designed can be obtained, and the accuracy of the core width of the ABS is improved. High density recording is possible.

Here, the forming process of the perpendicular recording write head according to the embodiment of the present invention will be described with reference to FIGS. 2 to 6. Here, only the forming process of the main magnetic pole will be described.
See Figure 2
First, for example, after providing an Al ₂ O ₃ buried layer 12 having a thickness of, for example, 0.5 μm on the main magnetic pole auxiliary layer 11 made of NiFe, a positive resist 13 is applied, and then a rectangular shape is formed. Exposure is performed using the first mask 14 on which a pattern is formed.
Process conditions at this time are mask exposure using a KRF stepper using a general KRF excimer resist.

See Figure 3
Next, the positive resist 13 is developed using, for example, a TMAH 2.38 percent solution to form a rectangular opening 15 having a width of, for example, 500 nm and a length of 5 μm. The first recess 16 having a depth of, for example, 500 nm is formed by performing ion milling with Ar gas.

See Figure 4
Next, after removing the positive resist 13, a new positive resist 17 is applied, and then the first recess 16 and a part of the first recess 16 are formed using a second mask 18 in which a large area rectangular pattern is formed. Are exposed so that they overlap.
Also in this process condition, mask exposure is performed using a KRF stepper using a general KRF excimer resist.

See Figure 5
Next, the positive resist 17 is developed using, for example, TMAH 2.38 percent solution to form a rectangular large-area opening 19 having a width of, for example, 10 μm and a length of 10 μm. A second recess 20 reaching the main magnetic pole auxiliary layer 11 is formed by ion milling with Ar gas through the opening 19.
At this time, the main magnetic pole auxiliary layer 11 is dug in the projected overlapping portion of the first recess 16 and the second recess 20.

See FIG.
Next, after removing the positive resist 17, a CoNiFe film is formed by sputtering so as to completely fill the first recess 16 and the second recess 20, and then the Al ₂ O ₃ buried layer 12 is formed by CMP. The main magnetic pole 21 embedded in the Al ₂ O ₃ buried layer 12 is formed by polishing and flattening the surface of the Al ₂ O ₃ layer.

In this case, the main magnetic pole 21 is composed of, for example, a light pole 22 having a neck height of 100 nm, a large-area rear end portion 23, and an overlapping portion 24 therebetween.
In this case, since the overlapping portion 24 bites into the main magnetic pole auxiliary layer 11, the presence of the overlapping portion 24 does not adversely affect magnetically.

  As described above, since the linear light pole part and the large area rear end part are formed by different masks, the straight line part that forms the neck height at the rear large area rear end part in the exposure / development process. The curved portion is not formed by being dragged, and it is possible to form a write magnetic pole having a neck height portion that is extremely straight and has high fidelity to the design.

Next, a first modification will be described with reference to FIG. 7, but only the final cross-sectional shape of the main magnetic pole will be described here.
See FIG.
FIG. 7 is a schematic cross-sectional view of the first modified example. In the first modified example, the depth of the first concave portion and the second concave portion are made the same, so that The thickness of the area rear end 23 is the same.

Next, a second modification will be described with reference to FIG. 8, but only the final cross-sectional shape of the main magnetic pole will be described here.
See FIG.
FIG. 8 is a schematic cross-sectional view of the second modified example. In the second modified example, the large-area rear end portion 25 is formed thick so that it also serves as the main magnetic pole auxiliary layer. Accordingly, the main magnetic pole auxiliary layer 11 is unnecessary.

Next, a third modification will be described with reference to FIGS. 9 and 10. Here, the mask shape and the final main magnetic pole shape will be described.
See FIG.
FIG. 9 is an explanatory diagram of a mask according to a third modified example. Here, as the first mask 14 and the second mask 26 which are exactly the same as those described above, a pentagonal shape with a top angle of, for example, 120 degrees is illustrated. A mask having a large area pattern is used.

See FIG.
FIG. 10 is a diagram for explaining the configuration of the third modification, in which the upper diagram is a schematic plan view and the lower diagram is a schematic cross-sectional view.
Also in the third modification, the cross-sectional shape is the same as that of the above-described embodiment, but the planar shape is configured such that the obtuse angle top portion of the pentagonal large-area rear end portion 27 and the light pole 22 overlap. .

  In the third modified example, the connection portion of the large area rear end portion 27 with the light pole 22 is tapered, so that good magnetic characteristics can be obtained, but the obtuse angle top portion of the large area rear end portion 27 is obtained. And the light pole 22 need to be aligned with high accuracy, so that the alignment margin is reduced.

Based on the above, a composite thin film magnetic head for perpendicular recording according to Embodiment 1 of the present invention will be described next with reference to FIG.
See FIG.
FIG. 11 is a diagram for explaining the configuration of a composite thin film magnetic head for perpendicular recording according to Embodiment 1 of the present invention. First, an Al ₂ O ₃ film (whichever is used) is formed on an Al ₂ O ₃ —TiC substrate which is a base of a slider. Also, a lower magnetic shield layer 31, a TMR film 32, a magnetic domain control film 33, an Al ₂ O ₃ film 34, and an upper magnetic shield layer 35 are provided.

Next, after an Al ₂ O ₃ film 36 is provided on the entire surface of the upper magnetic shield layer 35, a thickness of 1 to ₃ μm, for example, 1.0 μm, is formed on the Al ₂ O ₃ film 36 using a selective electrolytic plating method. A main magnetic pole auxiliary layer 11 made of NiFe is provided.
In addition, description is abbreviate | omitted about the plating base layer in an electrolytic plating process.

Next, after depositing an Al ₂ O ₃ film on the entire surface using a sputtering method, and planarizing using a CMP (chemical mechanical polishing) method, the thickness on the main magnetic pole auxiliary layer 11 is, for example, provided with a Al ₂ O ₃ burying layer 12 of 2.0 .mu.m, embedding recess of the head air bearing surface side Al ₂ O ₃ burying layer 12.

Next, after forming the first recess and the second recess reaching the main magnetic pole auxiliary layer 11 by the two-step ion milling process using the two types of masks described in the above embodiment, the positive resist is removed. Then, a CoNiFe film is formed using an electroplating method so as to completely fill the first and second recesses on the entire surface.
Again, description of the plating base layer in the electrolytic plating step is omitted.

Next, by polishing and flattening until the surface of the Al ₂ O ₃ buried layer 12 is exposed by CMP, the light pole 22 and the large area rear end portion 23 constituting the main magnetic pole are formed.

Next, a gap layer 37 made of a nonmagnetic material, for example, Al ₂ O ₃ , having a thickness of 30 to 100 nm, for example, 60 nm, is provided on the entire surface by sputtering.
In this case, the thickness of the gap layer 37 is set to be about 1 to 2 times the distance from the head medium facing surface to the surface of the backing layer of the perpendicular recording medium in the final magnetic head structure.

  Next, Cu is selectively formed on the gap layer 37 using a selective electrolytic plating method to form a planar spiral write coil 38, and then a photoresist is provided so as to cover the write coil 38. Is a covering insulating film 39.

Next, the NiFe layer is deposited again using the selective electrolytic plating method, and the NiFe layer deposited on the coating insulating film 39 is used as the return yoke 40, and the NiFe layer deposited on the side surface of the coating insulating film 39 on the head medium facing surface side. Is a shield layer 41.
The write coil 38 is wound around a connecting portion 42 formed integrally with the return yoke 40 that magnetically connects the large-area rear end portion 23 of the main magnetic pole and the return yoke 40.
Finally, the basic structure of the composite thin film magnetic head for perpendicular recording is obtained by cutting the head medium facing surface side and polishing the ABS surface so as to adjust the element height.

  The embodiments and examples of the present invention have been described above, but the present invention is not limited to the configurations and conditions described in the embodiments and examples, and various modifications can be made. In the description of the above embodiment, the first recess and the second recess are formed by ion milling using argon ions, but reactive ion etching using a chlorine-based gas may be used. It is.

  In the description of the above embodiment, a positive resist is used as a resist. However, the resist is not limited to a positive resist, and a negative resist may be used. What is necessary is just to reverse the light-shielding pattern provided in a mask.

  In the description of the above embodiment, the main magnetic pole is formed of CoNiFe. However, the present invention is not limited to CoNiFe, and other soft magnetic materials such as NiFe and CoFe may be used.

  In the description of the above embodiment, the second recess is formed after the first recess is formed. However, the formation of the second recess is not excluded.

The detailed features of the present invention will now be described with reference to FIG. 1 again.
Again see Figure 1
(Supplementary Note 1) The first concave portion 3 for embedding a thin rectangular light pole 6 having a width of 50 to 500 nm as the tip portion and the second concave portion 4 for embedding the rear end portion 7 of a large area are buried. A method of manufacturing a perpendicular recording magnetic head, wherein the formation is made in a different mask process when forming in the buried insulating film 2.
(Appendix 2) After forming the first recess 3, the second recess 4 is formed, and then the first recess 3 and the second recess 4 are completely embedded with the soft magnetic film 5. The method for manufacturing a perpendicular recording magnetic head according to appendix 1, further comprising a step of flattening by chemical mechanical polishing.
(Supplementary Note 3) The perpendicular recording magnetism according to Supplementary Note 1 or 2, wherein the surface of the main magnetic pole auxiliary layer 1 provided under the buried insulating film 2 is exposed by the second concave portion 4. Manufacturing method of the head.
(Supplementary Note 4) In the step of forming the second concave portion 4, a part of the main magnetic pole auxiliary layer 1 is dug in a projection overlapping portion with the first concave portion 3. A method of manufacturing a perpendicular recording magnetic head according to appendix 3.
(Supplementary Note 5) The supplementary note 1 or 2, wherein the rear end portion 7 of the large area also serves as a main magnetic pole auxiliary layer, and the main magnetic pole auxiliary layer 1 is not provided under the buried insulating film 2. Manufacturing method of perpendicular recording magnetic head.
(Additional remark 6) The depth of the said 2nd recessed part 4 is deeper than the depth of the said 1st recessed part 3, The manufacturing method of the perpendicular recording magnetic head of any one of Additional marks 1 thru | or 5 characterized by the above-mentioned.
(Additional remark 7) The manufacturing method of the perpendicular recording magnetic head of any one of Additional remark 1 thru | or 6 characterized by the planar shape of said 2nd recessed part 4 being a rectangle.

  As a practical example of the present invention, a write head constituting a composite thin film magnetic head for perpendicular recording is typical, but it is also applied to a write-only magnetic head.

It is explanatory drawing of the fundamental structure of this invention. It is explanatory drawing of the formation process to the middle of the write head for perpendicular recording of an embodiment of the invention. It is explanatory drawing of the formation process until the middle of FIG. 2 after the write head for perpendicular recording of embodiment of this invention. It is explanatory drawing of the formation process to the middle after FIG. 3 of the write-head for perpendicular recording of embodiment of this invention. FIG. 5 is an explanatory diagram of a forming process up to the middle of FIG. 4 and subsequent drawings of the perpendicular recording write head according to the embodiment of the present invention; FIG. 6 is an explanatory diagram of the formation process after FIG. 5 of the perpendicular recording write head according to the embodiment of the present invention; It is a schematic sectional drawing of the 1st modification. It is a schematic sectional drawing of the 2nd modification. It is explanatory drawing of the mask of a 3rd modification. It is composition explanatory drawing of the 3rd modification. 1 is a configuration explanatory diagram of a composite thin film magnetic head for perpendicular recording according to Embodiment 1 of the present invention. FIG. It is a schematic plan view of a core main magnetic pole part of a conventional perpendicular recording write head. It is explanatory drawing of the problem by refinement | miniaturization.

Explanation of symbols

1 main pole auxiliary layer 2 buried insulating film 3 first recess 4 second recess 5 soft magnetic film 6 write pole 7 rear portion 11 main pole auxiliary layer 12 Al ₂ O ₃ burying layer 13 positive resist 14 second 1 mask 15 opening 16 first recess 17 positive resist 18 second mask 19 large area opening 20 second recess 21 main magnetic pole 22 light pole 23 large area rear end 24 overlap portion 25 large area rear end Part 26 second mask 27 large area rear end part 31 lower magnetic shield layer 32 TMR film 33 magnetic domain control film 34 Al ₂ O ₃ film 35 upper magnetic shield layer 36 Al ₂ O ₃ film 37 gap layer 38 write coil 39 covering insulation Film 40 Return yoke 41 Shield layer 42 Connection 50 Core main magnetic pole 51 Neck height 52 Neck height

Claims (5)

When forming a first concave portion for embedding a thin rectangular light pole having a width of 50 to 500 nm as a front end portion and a second concave portion for embedding a rear end portion of a large area in the buried insulating film. And a method of manufacturing a perpendicular recording magnetic head, wherein the perpendicular recording magnetic head is formed by different mask processes. After forming the first recess, the second recess is formed, and then the first recess and the second recess are completely filled with a soft magnetic film, and then planarized by chemical mechanical polishing. 2. The method of manufacturing a perpendicular recording magnetic head according to claim 1, further comprising the step of: 3. The method of manufacturing a perpendicular recording magnetic head according to claim 1, wherein the surface of the main magnetic pole auxiliary layer provided under the buried insulating film is exposed by the second recess. 4. The perpendicular recording according to claim 3, wherein in the step of forming the second concave portion, a part of the main magnetic pole auxiliary layer is dug in a projection overlapping portion with the first concave portion. Manufacturing method of magnetic head. 3. The perpendicular recording magnetic head according to claim 1, wherein a rear end portion of the large area also serves as a main magnetic pole auxiliary layer, and no main magnetic pole auxiliary layer is provided under the buried insulating film. Method.

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