Abstract:
A manufacturing method of a thin-film magnetic head provided with an MR element includes a step of forming an MR multi-layered structure in which a current flows in a direction perpendicular to surfaces of layers of the MR multi-layered structure, on a lower electrode film, a step of depositing an insulation film on the formed MR multi-layered structure and the lower electrode film, a step of flattening the deposited insulation film until at least upper surface of the MR multi-layered structure is exposed, and a step of forming an upper electrode film on the flattened insulation film and the MR multi-layered structure.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a manufacturing method of a thin-film magnetic head with a magnetoresistive effect (MR) element for detecting magnetic intensity in a magnetic recording medium and for outputting a read signal. 
     DESCRIPTION OF THE RELATED ART 
     Recently, in order to satisfy the demand for higher recording density and downsizing in a hard disk drive (HDD) apparatus, higher sensitivity and larger output of a thin-film magnetic head are required. Thus, improvement in characteristics of a general giant magnetoresistive effect (GMR) head with a GMR element which is current-manufactured are now strenuously proceeding and also development of a tunnel magnetoresistive effect (TMR) head with a TMR element is energetically performed. 
     Because of the difference in flowing directions of their sense currents, structures of these TMR head and general GMR head differ from each other. One head structure in which a sense current flows in a direction parallel with surfaces of laminated layers as in the general GMR head is called as a current in plane (CIP) structure, whereas the other head structure in which a sense current flows in a direction perpendicular to surfaces of laminated layers as in the TMR head is called as a current perpendicular to plane (CPP) structure. 
     In recent years, CPP-GMR heads not CIP-GMR heads are being developed. For example, Japanese patent publication No. 05275769A discloses such a CPP-GMR head. Japanese patent publication Nos. 04360009A, 05090026A and 09129445A disclose CPP-GMR heads having anti-ferromagnetic coupling magnetic multi-layered films consisting of a plurality of magnetic layers stuck with each other via nonmagnetic layers (Cu, Ag, Au or others). 
     Also, provided are CPP-GMR heads with spin valve magnetic multi-layered films including such as specular type magnetic multi-layered films or dual-spin valve type magnetic multi-layered films. 
     Conventionally a lift-off method or a contact-hole method has been used for fabricating such CPP-GMR heads or TMR heads. 
     FIGS. 1 a  to  1   f  show sectional views illustrating a part of a conventional fabrication process of a CPP-GMR head by the lift-off method. 
     First, as shown in FIG. 1 a,  a lower electrode film  11  and a MR multi-layered film  12 ′ are sequentially deposited on an insulation film  10  formed on a substrate (not shown). 
     Then, a photo-resist pattern  13  of a two-layers structure is formed thereon as shown in FIG. 1 b,  and the MR multi-layered film  12 ′ is patterned by ion milling to obtain a MR multi-layered structure  12  as shown in FIG. 1 c.    
     Then, an insulation film  14 ′ is deposited thereon as shown in FIG. 1 d,  and the photo-resist pattern  13  is removed or lifted off to obtain a patterned insulation film  14  as shown in FIG. 1 e.    
     Thereafter, an upper electrode film  15  is deposited thereon as shown in FIG. 1 f.    
     In executing this lift-off method, it is necessary that no insulation film  14 ′ deposited on the side surface of a stepped portion of the photo-resist pattern  13  is bridged over the stepped portion. Thus, in general, a T-shaped two-layers structure photo-resist pattern with an undercut is used in order to improve the lift-off performance. 
     However, if the amount or depth of the undercut of the photo-resist pattern  13  is small, the insulation film may be deposited on a side surface of a base  13   a  of the two-layers structure photo-resist pattern  13  causing occurrence of unnecessary burr around the removed photo-resist pattern. Contrary to this, if the undercut amount is large, a burr will be prevented from occurrence but the width of the base  13   a  of the photo-resist pattern  13  will become extremely narrow causing lost of the pattern. 
     Also, according to the lift-off method, a part of the insulation film  14  intruded into the undercut portion may be remained to overlap with a top surface of the MR multi-layered structure  12  as shown in FIG. 1 e.  Such overlapped insulation film causes ambiguity in a track width and limits fine micromachining of the track width. Since the length of each overlapped insulation film on the MR multi-layered structure is about 100 nm, it is impossible to fabricate by the lift-off method a recent TMR element or GMR element with an extremely narrow track width of 200 nm or less, such as around 100 nm. 
     In typical MR multi-layered structure of the TMR or GMR element, a free layer is located at a middle of the MR multi-layered structure and its width determines the track width. Therefore, if the MR multi-layered structure is formed by ion milling using the conventional photo-resist mask, the bottom of the MR multi-layered structure will widen causing an effective track width to increase. It is desired that the side surface of the MR multi-layered structure is perpendicular to the substrate surface and this may be implemented by an ion milling method using a hard mask or by a reactive ion etching (RIE) method. However, in principal, such methods cannot be utilized in the lift-off method. 
     FIGS. 2 a  to  2   g  show sectional views illustrating a part of a conventional fabrication process of a CPP-GMR head by the contact-hole method. 
     First, as shown in FIG. 2 a,  a lower electrode film  21  and a MR multi-layered film  22 ′ are sequentially deposited on an insulation film  20  formed on a substrate (not shown). 
     Then, a photo-resist pattern  23  is formed thereon as shown in FIG. 2 b,  and the MR multi-layered film  22 ′ is patterned by ion milling to obtain a MR multi-layered structure  22  as shown in FIG. 2 c.    
     Then, after the photo-resist pattern  23  is removed, an insulation film  24 ′ is deposited thereon as shown in FIG. 2 d.    
     Then, as shown in FIG. 2 e,  a photo-resist pattern  26  with an opening  26   a  located at a contact hole is formed on the insulation film  24 ′. 
     Then, as shown in FIG. 2 f,  the insulation film  24 ′ is patterned by ion milling to obtain an insulation film  24  provided with a contact hole  24   a  on the MR multi-layered structure  22 , and thereafter the photo-resist pattern  26  is removed. 
     After that, an upper electrode film  25  is deposited thereon as shown in FIG. 2 g.    
     According to this contact-hole method, however, since two photo processes with respect to the photo-resist patterns are executed, the amount of the overlap due to a deviation between both the alignments will become about 30 nm. Such overlap amount of the insulation film cannot be negligible as well as in case of the lift-off method. 
     As aforementioned, according to the conventional manufacturing method, it is quite difficult to fabricate a GMR head with the CPP structure or a TMR head having a very narrow track width of 200 nm or less, and therefore it has been demanded to provide a novel fabrication method capable of fabricating such CPP-GMR head or TMR head with the extremely narrow track width. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a manufacturing method of a thin-film magnetic head with an MR element, whereby an MR element with a structure in which a sense current flows in a direction perpendicular to surfaces of laminated layers and with a track width of 200 nm or less can be easily manufactured. 
     According to the present invention, a manufacturing method of a thin-film magnetic head provided with an MR element includes a step of forming an MR multi-layered structure in which a current flows in a direction perpendicular to surfaces of layers of the MR multi-layered structure, on a lower electrode film, a step of depositing an insulation film on the formed MR multi-layered structure and the lower electrode film, a step of flattening the deposited insulation film until at least upper surface of the MR multi-layered structure is exposed, and a step of forming an upper electrode film on the flattened insulation film and the MR multi-layered structure. 
     Without using a lift-off method, an insulation film is deposited on the MR multi-layered structure and the lower electrode film, and then this insulation film is flattened until at least the upper surface of the MR multi-layered structure is exposed or appeared to form a flattened insulation film on and around the MR multi-layered structure. 
     Since a normal resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using the lift-off method can be formed. 
     Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure, a very precise shape of the MR multi-layered structure can be expected. 
     Furthermore, because no burr nor overlap of the insulation film will occur and thus a very strict track width can be defined, it is possible to easily fabricate an MR element with a structure in which a sense current flows in a direction perpendicular to surfaces of laminated layers and with an extremely narrow track width of 200 nm or less. 
     It is preferred that the forming step of the MR multi-layered structure includes depositing a MR multi-layered film on the lower electrode film, forming a mask on the deposited MR multi-layered film, patterning the deposited MR multi-layered film using the formed mask, and removing the mask to form the MR multi-layered structure. 
     It is also preferred that the forming step of the MR multi-layered structure includes depositing a MR multi-layered film on the lower electrode film, forming a mask on the deposited MR multi-layered film, and patterning the deposited MR multi-layered film using the formed mask to form the MR multi-layered structure, the mask being remained to use as a cap layer of the MR multi-layered structure. 
     It is further preferred that the flattening step includes executing a low angle ion beam etching (IBE) that uses a beam having a low incident angle with surfaces of laminated films. 
     Also, it is preferred that the flattening step includes executing a low angle IBE that uses a beam having a low incident angle with surfaces of laminated films, and executing a low rate IBE with a low etching rate. 
     It is further preferred that the flattening step includes executing a low angle IBE that uses a beam having a low incident angle with surfaces of laminated films, executing a flattening process using gas clusters ion beam (GCIB), and executing a low rate IBE with a low etching rate. 
     It is preferred that the low incident angle in the IBE is 0 to 40 degrees. 
     It is also preferred that the flattening step includes executing a flattening process using GCIB, and executing a low rate IBE with a low etching rate. 
     It is further preferred that the flattening step includes executing a chemical mechanical polishing (CMP). In this case, preferably the method further includes a step of forming a contact hole on the insulation film on the MR multi-layered structure before executing the flattening step. 
     It is preferred that termination of the flattening step is managed by monitoring a flattening step time or by executing endpoint detection. The endpoint detection may be executed by using a secondary ion mass spectroscopy (SIMS). 
     It is also preferred that the MR multi-layered structure is a TMR multi-layered structure, a CPP-GMR multi-layered structure, a TMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer in the TMR multi-layered structure, or a CPP-GMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer in the CPP-GMR multi-layered structure. 
     According to the present invention, also, a manufacturing method of a thin-film magnetic head provided with a MR element includes a step of forming an MR multi-layered structure in which a current flows in a direction perpendicular to surfaces of layers of the MR multi-layered structure, on a lower electrode film, a step of depositing an insulation film on a cover film formed on an upper surface of the formed MR multi-layered structure and the lower electrode film, a step of removing the deposited insulation film on the cover film formed on the MR multi-layered structure until the cover film is exposed or before the cover film is exposed by executing CMP, and a step of forming an upper electrode film on the cover film or the MR multi-layered structure and the insulation film. 
     Without using a lift-off method, an insulation film is deposited on the MR multi-layered structure and the lower electrode film, and then this insulation film is removed by CMP until or before a cover film on the upper surface of the MR multi-layered structure is exposed or appeared to form an insulation film on and around the MR multi-layered structure. 
     Since a normal resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using the lift-off method can be formed. 
     Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure, a very precise shape of the MR multi-layered structure can be expected. 
     Furthermore, because no burr nor overlap of the insulation film will occur and thus a very strict track width can be defined, it is possible to easily fabricate an MR element with a structure in which a sense current flows in a direction perpendicular to surfaces of laminated layers and with an extremely narrow track width of 200 nm or less. 
     In addition, when the insulation film is deposited, a recess may be produced around the MR multi-layered structure. Thus, a part of the deposited upper electrode film will enter the recess and a magnetic field passing through this electrode film part will be applied to the MR multi-layered structure causing its MR characteristics to deteriorate. However, according to the present invention, since the recess is removed by CMP, it is possible to improve MR characteristics. 
     It is preferred that the forming step of the MR multi-layered structure includes depositing a MR multi-layered film on the lower electrode film, forming a mask on the deposited MR multi-layered film, and patterning the deposited MR multi-layered film using the formed mask to form the MR multi-layered structure. 
     It is also preferred that the cover film is the formed mask. In this case, the removing step includes removing the deposited insulation film on the mask formed on the MR multi-layered structure until a part of the mask is removed by executing the CMP, and removing remained part of the mask is removed after the CMP. 
     It is further preferred that the forming step of the MR multi-layered structure includes depositing sequentially a MR multi-layered film and a first CMP stop film on the lower electrode film, forming a mask on the deposited first CMP stop film, and patterning the deposited first CMP stop film and the deposited MR multi-layered film using the formed mask to form the MR multi-layered structure. 
     It is preferred that the cover film is the first CMP stop film. 
     It is also preferred that the method further includes a step of depositing a second CMP stop film on the deposited insulation film. 
     It is further preferred that the removing step includes removing the deposited insulation film on the first CMP stop film formed on the MR multi-layered structure until the first CMP stop film is exposed by executing the CMP. 
     It is more preferred that the method further includes a step of removing the first and second CMP stop films after the CMP. 
     It is further preferred that the forming step of the MR multi-layered structure includes depositing sequentially a MR multi-layered film and a milling stop film on the lower electrode film, forming a mask on the deposited milling stop film, and patterning the deposited milling stop film and the deposited MR multi-layered film using the formed mask to form the MR multi-layered structure. 
     Preferably, the cover film is the milling stop film. 
     It is preferred that the removing step includes removing the deposited insulation film on the milling stop film formed on the MR multi-layered structure before the milling stop film is exposed by executing the CMP. 
     It is further preferred that the method further includes a step of removing the insulation film on the milling stop film by milling after the CMP, the milling stop film being remained. 
     Preferably, the CMP is a precise CMP with a low lapping rate for remaining a low height difference. A lapping rate of the precise CMP is preferably 50 nm/min or less. 
     It is preferred that the precise CMP is executed using a slurry consisting of one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite, or of a mixture containing one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite. 
     It is further preferred that the precise CMP is executed using a slurry with an average particle diameter of 100 nm or less. 
     It is also preferred that termination of the CMP is managed by monitoring a polishing process time. 
     It is further preferred that the MR multi-layered structure is a tunnel MR multi-layered structure or a CPP-GMR multi-layered structure. 
     Further objects and advantages of the present invention will be apparent from the following description of preferred embodiments of the invention as illustrated in the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1 a  to  1   f  already disclosed show sectional views illustrating a part of a conventional fabrication process of a CPP-GMR head by a lift-off method; 
     FIGS. 2 a  to  2   g  already disclosed show sectional views illustrating a part of a conventional fabrication process of a CPP-GMR head by a contact-hole method; 
     FIGS. 3 a  to  3   f  show sectional views illustrating a part of a fabrication process of a TMR head or a CPP-GMR head as a preferred embodiment according to the present invention; 
     FIGS. 4 a  to  4   c  show sectional views illustrating in detail an actual flattening process in the embodiment of FIGS. 3 a  to  3   f;    
     FIG. 5 shows a sectional view schematically illustrating an example of a multi-layered structure of the TMR head fabricated by the embodiment of FIGS. 3 a  to  3   f;    
     FIG. 6 shows a sectional view schematically illustrating another example of a multi-layered structure of the TMR head fabricated by the embodiment of FIGS. 3 a  to  3   f;    
     FIGS. 7 a  to  7   g  show sectional views illustrating a part of a fabrication process of a TMR head or a CPP-GMR head as another embodiment according to the present invention; 
     FIGS. 8 a  to  8   g  show sectional views illustrating a part of a fabrication process of a TMR head or a CPP-GMR head as a further embodiment according to the present invention; 
     FIGS. 9 a  to  9   h  show sectional views illustrating a part of a fabrication process of a TMR head or a CPP-GMR head as a still further embodiment according to the present invention; 
     FIGS. 10 a  to  10   f  show sectional views illustrating a part of a fabrication process of a TMR head or a CPP-GMR head as a further embodiment according to the present invention; 
     FIGS. 11 a  to  11   h  show sectional views illustrating a part of a fabrication process of a TMR head or a CPP-GMR head as a still further embodiment according to the present invention; 
     FIGS. 12 a  to  12   g  show sectional views illustrating a part of a fabrication process of a TMR head or a CPP-GMR head as a still more further embodiment according to the present invention; 
     FIGS. 13 a  to  13   h  show sectional views illustrating a part of a fabrication process of a TMR head or a CPP-GMR head as a further embodiment according to the present invention; and 
     FIGS. 14 a  to  14   g  show sectional views illustrating a part of a fabrication process of a TMR head or a CPP-GMR head as a still further embodiment according to the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 3 a  to  3   f  illustrate a part of a fabrication process of a TMR head or a CPP-GMR head as a preferred embodiment according to the present invention. 
     First, as shown in FIG. 3 a,  a lower electrode film  31  which also functions as a magnetic shield film and a MR multi-layered film  32 ′ are sequentially deposited on an insulation film  30  formed on a substrate (not shown). 
     Then, a photo-resist pattern  33  with a straight shaped side wall is formed thereon as shown in FIG. 3 b.    
     Then, the MR multi-layered film  32 ′ with a thickness of about 35-55 nm is patterned by IBE, RIE, reactive ion beam etching (RIBE) or sputtering using the photo-resist pattern  33  as a mask to obtain a MR multi-layered structure  32  as shown in FIG. 3 c.  The upper surface of this MR multi-layered structure  32  operates as a junction. 
     The MR multi-layered structure  32  may be for example a TMR multi-layered structure, a CPP-GMR multi-layered structure, a TMR or CPP-GMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer, a CPP-GMR multi-layered structure with an anti-ferromagnetic coupling type magnetic films, a CPP-GMR multi-layered structure with a specular type spin-valve magnetic films, or a CPP-GMR multi-layered structure with a dual spin-valve type magnetic films. 
     Then, after the photo-resist pattern  33  used as a mask is removed, an insulation film  34 ′ of Al 2 O 3  or SiO 2  for example with a thickness of about 50-100 nm is deposited on the entire surface as shown in FIG. 3 d.  Thus, the insulation film  34 ′ is protruded at the junction. In order to ensure reliable electrical insulation, it is desired that the thickness of this insulation film  34 ′ is determined to a value equal to or thicker than that of the MR multi-layered structure  32 . 
     Thereafter, as shown in FIG. 3 e,  the insulation film  34 ′ is flattened until at least the upper surface or junction of the MR multi-layered structure  32  is exposed or appeared by executing a low angle IBE using a beam having a low incident angle with surfaces of laminated layers, and thus a flattened insulation film  34  is obtained. 
     In this case, it is preferred that an angle of the incident ion beam of the low angle IBE with the surfaces of laminated layers is 0-40 degrees. If this angle of the incident ion beam is more than 40 degrees, the flattening of the insulation film becomes difficult. The angle of the incident ion beam of the low angle IBE with the surfaces of laminated layers is more preferably 0-30 degrees, and most preferably 0-20 degrees. 
     Termination of the flattening may be managed by monitoring a flattening process time or by executing an endpoint-detection process using a SIMS. In the latter case, because of a very small top surface area of the MR multi-layered structure  32 , it is desired to laminate a film specifically used for endpoint detection using the SIMS in order to easily perform the endpoint-detection process. Concretely, the insulation film  34 ′ is deposited to a height equal to or somewhat lower than that of the MR multi-layered structure  32 , then an extremely thin film specially used for endpoint detection such as Co, Mn, Ti, Ta, Cr or else is deposited, and thereafter the insulation film  34 ′ is again deposited thereon to make the endpoint detection process easier. 
     Etching conditions of an example of the low angle IBE are as follows: 
     Beam incident angle: 20 degrees; 
     Acceleration voltage: 300 V; 
     Beam current: 0.35 mA/cm 2 ; 
     Ar gas pressure: 2.4×10 −4  Torr; 
     Substrate temperature: 30° C.; 
     Etching time: about 15 minutes. 
     After that, an upper electrode film  35  which also functions as a magnetic shield film is deposited on the flattened insulation film  34  and the MR multi-layered structure  32  as shown in FIG. 3 f.    
     A hard mask may be used instead of the photo-resist pattern  33 . When a conductive hard mask is used, this hard mask may be remained without removing and used as a part of a cap layer of the MR multi-layered structure  32 . 
     FIGS. 4 a  to  4   c  illustrate in detail an actual flattening process in the embodiment of FIGS. 3 a  to  3   f.    
     As shown in these figures, in this embodiment, due to the flattening process of the insulation film  34 , an upper portion of a cap layer  32   f  of the MR multi-layered structure  32  is in fact etched and thus a triangular protrusion  32   f ′ of the cap layer with a height that is equal to several percents of a width of the upper surface of the MR multi-layered structure  32  (junction width) is formed at this portion. Thus, it is desired to deposit a layer with a thickness larger than the height of the protrusion  32   f ′ as the cap layer  32   f.    
     FIG. 5 schematically illustrates an example of a multi-layered structure of the TMR head fabricated by the embodiment of FIGS. 3 a  to  3   f.    
     As shown in the figure, the lower electrode film  31  with a thickness of about 2000 nm, which also functions as a magnetic shield film, is laminated on the insulation film  30 , the MR multi-layered structure  32  is laminated thereon, and the upper electrode film  35  with a thickness of about 2000 nm, which also functions as a magnetic shield film is laminated thereon. The MR multi-layered structure  32  is composed of an under layer  32   a  with a thickness of about 0-20 nm, a pinning layer  32   b  with a thickness of about 10-20 nm, a pinned layer  32   c  with a thickness of about 5-6 nm, a tunnel barrier layer  32   d  with a thickness of about 1 nm, a free layer  32   e  with a thickness of about 4-6 nm, and a cap layer  32   f  with a thickness of about 5-10 nm sequentially laminated in this order. The under layer  32   a  with a thickness of 0 nm corresponds to a case where there is no under layer. The insulation film  34  is also formed on the lower electrode film  31  around the MR multi-layered structure  32 . 
     The structure of a CPP-GMR head is the same as that of the TMR head except that a nonmagnetic metal layer with a thickness of about 2-5 nm is formed instead of the tunnel barrier layer  32   d.    
     It is desired that the cap layer  32   f  is made of one of tantalum (Ta), rhodium (Rh), ruthenium (Ru), osmium (Os), tungsten (W), palladium (Pd), platinum (Pt) and gold (Au), or an alloy containing one of Ta, Rh, Ru, Os, W, Pd, Pt and Au. 
     FIG. 6 schematically illustrates another example of a multi-layered structure of the TMR head fabricated by the embodiment of FIGS. 3 a  to  3   f.    
     In this example, the TMR multi-layered structure has a bias layer for defining a magnetization direction of a free layer. As shown in the figure, the lower electrode film  31  with a thickness of about 2000 nm, which also functions as a magnetic shield film, is laminated on the insulation film  30 , the MR multi-layered structure  32  is laminated thereon, and the upper electrode film  35  with a thickness of about 2000 nm, which also functions as a magnetic shield film is laminated thereon. The MR multi-layered structure  32  is composed of an under layer  32   a  with a thickness of about 0-20 nm, a pinning layer  32   b  with a thickness of about 10-20 nm, a pinned layer  32   c  with a thickness of about 5-6 nm, a tunnel barrier layer  32   d  with a thickness of about 1 nm, a free layer  32   e  with a thickness of about 4-6 nm, a nonmagnetic metal layer  32   g  with a thickness of about 0.1-3 nm, an anti-ferromagnetic layer  32   h  with a thickness of about 10 nm, and a cap layer  32   f  with a thickness of about 5-10 nm sequentially laminated in this order. The under layer  32   a  with a thickness of 0 nm corresponds to a case where there is no under layer. The insulation film  34  is also formed on the lower electrode film  31  around the MR multi-layered structure  32 . 
     The structure of a CPP-GMR head is the same as that of the TMR head except that a nonmagnetic metal layer with a thickness of about 2-5 nm is formed instead of the tunnel barrier layer  32   d.    
     It is desired that the cap layer  32   f  is made of one of tantalum (Ta), rhodium (Rh), ruthenium (Ru), osmium (Os), tungsten (W), palladium (Pd), platinum (Pt) and gold (Au), or an alloy containing one of Ta, Rh, Ru, Os, W, Pd, Pt and Au. 
     As aforementioned, according to this embodiment, the insulation film  34 ′ is deposited on the MR multi-layered structure  32  and the lower electrode film  31 , and then this insulation film  34 ′ is flattened until at least the upper surface of the MR multi-layered structure  32  is exposed or appeared by executing a low angle IBE to form a flattened insulation film  34  on and around the MR multi-layered structure  32 . 
     Since a resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using a lift-off method can be formed. Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure  32 , a very precise shape of the MR multi-layered structure  32  can be expected. Furthermore, because no burr nor overlap of the insulation film  34  will occur and thus a very strict track width can be defined, it is possible to easily fabricate a TMR element or GMR element with an extremely narrow track width of 200 nm or less. In fact, a TMR element with a track width of 100 nm and good output characteristics could be fabricated according to this embodiment. 
     FIGS. 7 a  to  7   g  illustrate a part of a fabrication process of a TMR head or a CPP-GMR head as another embodiment according to the present invention. 
     First, as shown in FIG. 7 a,  a lower electrode film  71  which also functions as a magnetic shield film and a MR multi-layered film  72 ′ are sequentially deposited on an insulation film  70  formed on a substrate (not shown). 
     Then, a photo-resist pattern  73  with a straight shaped side wall is formed thereon as shown in FIG. 7 b.    
     Then, the MR multi-layered film  72 ′ is patterned by IBE, RIE, RIBE or sputtering using the photo-resist pattern  73  as a mask to obtain a MR multi-layered structure  72  as shown in FIG. 7 c.  The upper surface of this MR multi-layered structure  72  operates as a junction. 
     The MR multi-layered structure  72  may be for example a TMR multi-layered structure, a CPP-GMR multi-layered structure, a TMR or CPP-GMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer, a CPP-GMR multi-layered structure with an anti-ferromagnetic coupling type magnetic films, a CPP-GMR multi-layered structure with a specular type spin-valve magnetic films, or a CPP-GMR multi-layered structure with a dual spin-valve type magnetic films. 
     Then, after the photo-resist pattern  73  used as a mask is removed, an insulation film  74 ″ is deposited on the entire surface as shown in FIG. 7 d.  Thus, the insulation film  74 ″ is protruded at the junction. In order to ensure reliable electrical insulation, it is desired that the thickness of this insulation film  74 ″ is determined to a value equal to or thicker than that of the MR multi-layered structure  72 . 
     Thereafter, as shown in FIG. 7 e,  the insulation film  74 ″ is flattened by executing a low angle IBE using a beam having a low incident angle with surfaces of laminated layers, and thus a flattened insulation film  74 ′ is obtained. This flattening is stopped before at least the upper surface or junction of the MR multi-layered structure  72  is exposed or appeared. 
     In this case, it is preferred that an angle of the incident ion beam of the low angle IBE with the surfaces of laminated layers is 0-40 degrees. If this angle of the incident ion beam is more than 40 degrees, the flattening of the insulation film becomes difficult. The angle of the incident ion beam of the low angle IBE with the surfaces of laminated layers is more preferably 0-30 degrees, and most preferably 0-20 degrees. 
     Termination of the flattening may be managed by monitoring a flattening process time. 
     Etching conditions of an example of the low angle IBE are as follows: 
     Beam incident angle: 20 degrees; 
     Acceleration voltage: 300 V; 
     Beam current: 0.35 mA/cm 2 ; 
     Ar gas pressure: 2.4×10 −4  Torr; 
     Substrate temperature: 30° C.; 
     Etching time: about 12 minutes. 
     Then, as shown in FIG. 7 f,  the insulation film  74 ′ is flattened until at least the upper surface or junction of the MR multi-layered structure  72  is exposed or appeared by executing a low rate IBE with a low etching rate such as an etching rate of 2 nm/min or less for etching of SiO 2 , and thus a flattened insulation film  74  is obtained. 
     Termination of the latter flattening may be managed by monitoring a flattening process time or by executing an endpoint-detection process using a SIMS. In the latter case, because of a very small top surface area of the MR multi-layered structure  72 , it is desired to laminate a film specifically used for endpoint detection using the SIMS in order to easily perform the endpoint-detection process. Concretely, the insulation film  74 ″ is deposited to a height equal to or somewhat lower than that of the MR multi-layered structure  72 , then an extremely thin film specially used for endpoint detection is deposited, and thereafter the insulation film  74 ″ is again deposited thereon to make the endpoint detection process easier. 
     Etching conditions of an example of the low rate IBE are as follows: 
     Beam incident angle: 90 degrees; 
     Acceleration voltage: 250 V; 
     Beam current: 0.1 MA/cm 2 ; 
     Ar gas pressure: 2×10 −4  Torr; 
     Substrate temperature: 50° C.; 
     Etching time: about 10 minutes. 
     After that, an upper electrode film  75  which also functions as a magnetic shield film is deposited on the flattened insulation film  74  and the MR multi-layered structure  72  as shown in FIG. 7 g.    
     A hard mask may be used instead of the photo-resist pattern  73 . When a conductive hard mask is used, this hard mask may be remained without removing and used as a part of a cap layer of the MR multi-layered structure  72 . 
     Thickness and material of each film or each layer in this embodiment are the same as those in the embodiment of FIGS. 3 a - 3   f.  Also, configuration of the MR multi-layered structure  72  is the same as that of the MR multi-layered structure  32  in the embodiment of FIGS. 3 a - 3   f.    
     As aforementioned, according to this embodiment, the insulation film  74 ″ is deposited on the MR multi-layered structure  72  and the lower electrode film  71 , then this insulation film  74 ″ is flattened to a certain extent, and thereafter the insulation film  74 ′ is flattened by the low rate IBE using endpoint-detection of SIMS until at least the upper surface of the MR multi-layered structure  72  is exposed to form a flattened insulation film  74  on and around the MR multi-layered structure  72 . 
     Since a resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using a lift-off method can be formed. Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure  72 , a very precise shape of the MR multi-layered structure  72  can be expected. Furthermore, because no burr nor overlap of the insulation film  74  will occur and thus a very strict track width can be defined, it is possible to easily fabricate a TMR element or GMR element with an extremely narrow track width of 200 nm or less. In fact, a TMR element with a track width of 100 nm and good output characteristics could be fabricated according to this embodiment. 
     In addition, according to this embodiment, since the upper surface of the MR multi-layered structure  72  is exposed by the low rate IBE using endpoint-detection of SIMS, the termination of the flattening process can be very easily and precisely managed. 
     FIGS. 8 a  to  8   g  illustrate a part of a fabrication process of a TMR head or a CPP-GMR head as a further embodiment according to the present invention. 
     First, as shown in FIG. 8 a,  a lower electrode film  81  which also functions as a magnetic shield film and a MR multi-layered film  82 ′ are sequentially deposited on an insulation film  80  formed on a substrate (not shown). 
     Then, a photo-resist pattern  83  with a straight shaped side wall is formed thereon as shown in FIG. 8 b.    
     Then, the MR multi-layered film  82 ′ is patterned by IBE, RIE, RIBE or sputtering using the photo-resist pattern  83  as a mask to obtain a MR multi-layered structure  82  as shown in FIG. 8 c.  The upper surface of this MR multi-layered structure  82  operates as a junction. 
     The MR multi-layered structure  82  may be for example a TMR multi-layered structure, a CPP-GMR multi-layered structure, a TMR or CPP-GMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer, a CPP-GMR multi-layered structure with an anti-ferromagnetic coupling type magnetic films, a CPP-GMR multi-layered structure with a specular type spin-valve magnetic films, or a CPP-GMR multi-layered structure with a dual spin-valve type magnetic films. 
     Then, after the photo-resist pattern  83  used as a mask is removed, an insulation film  84 ″ is deposited on the entire surface as shown in FIG. 8 d.  Thus, the insulation film  84 ″ is protruded at the junction. In order to ensure reliable electrical insulation, it is desired that the thickness of this insulation film  84 ″ is determined to a value equal to or thicker than that of the MR multi-layered structure  82 . 
     Thereafter, as shown in FIG. 8 e,  the insulation film  84 ″ is flattened by executing a GCIB, and thus a flattened insulation film  84 ′ is obtained. This flattening is stopped before at least the upper surface or junction of the MR multi-layered structure  82  is exposed or appeared. 
     The flattening process using GCIB consists of producing gas clusters by ejecting a gas such as Ar gas into a high vacuum environment and rapidly cooling the gas, and bumping the produced gas clusters against a surface of an object so as to flatten the surface. 
     Termination of the flattening may be managed by monitoring a flattening process time. 
     Flattening conditions of an example of the GCIB are as follows: 
     Acceleration voltage: 15 kV; 
     Dose amount: 1×10 16  ions/cm 2 . 
     Then, as shown in FIG. 8 f,  the insulation film  84 ′ is flattened until at least the upper surface or junction of the MR multi-layered structure  82  is exposed or appeared by executing a low rate IBE with a low etching rate such as an etching rate of 2 nm/min or less for etching of SiO 2 , and thus a flattened insulation film  84  is obtained. 
     Termination of the latter flattening may be managed by monitoring a flattening process time or by executing an endpoint-detection process using a SIMS. In the latter case, because of a very small top surface area of the MR multi-layered structure  82 , it is desired to laminate a film specifically used for endpoint detection using the SIMS in order to easily perform the endpoint-detection process. Concretely, the insulation film  84 ″ is deposited to a height equal to or somewhat lower than that of the MR multi-layered structure  82 , then an extremely thin film specially used for endpoint detection is deposited, and thereafter the insulation film  84 ″ is again deposited thereon to make the endpoint detection process easier. 
     Etching conditions of an example of the low rate IBE are as follows: 
     Beam incident angle: 90 degrees; 
     Acceleration voltage: 250 V; 
     Beam current: 0.1 mA/cm 2 ; 
     Ar gas pressure: 2×10 −4  Torr; 
     Substrate temperature: 50° C.; 
     Etching time: about 15 minutes. 
     After that, an upper electrode film  85  which also functions as a magnetic shield film is deposited on the flattened insulation film  84  and the MR multi-layered structure  82  as shown in FIG. 8 g.    
     A hard mask may be used instead of the photo-resist pattern  83 . When a conductive hard mask is used, this hard mask may be remained without removing and used as a part of a cap layer of the MR multi-layered structure  82 . 
     Thickness and material of each film or each layer in this embodiment are the same as those in the embodiment of FIGS. 3 a - 3   f.  Also, configuration of the MR multi-layered structure  82  is the same as that of the MR multi-layered structure  32  in the embodiment of FIGS. 3 a - 3   f.    
     As aforementioned, according to this embodiment, the insulation film  84 ′ is deposited on the MR multi-layered structure  82  and the lower electrode film  81 , then this insulation film  84 ″ is flattened using GCIB to a certain extent, and thereafter the insulation film  84 ′ is flattened by the low rate IBE using endpoint-detection of SIMS until at least the upper surface of the MR multi-layered structure  82  is exposed to form a flattened insulation film  84  on and around the MR multi-layered structure  82 . 
     Since a resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using a lift-off method can be formed. Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure  82 , a very precise shape of the MR multi-layered structure  82  can be expected. Furthermore, because no burr nor overlap of the insulation film  84  will occur and thus a very strict track width can be defined, it is possible to easily fabricate a TMR element or GMR element with an extremely narrow track width of 200 nm or less. In fact, a TMR element with a track width of 100 nm and good output characteristics could be fabricated according to this embodiment. 
     In addition, according to this embodiment, since the upper surface of the MR multi-layered structure  82  is exposed by the low rate IBE using endpoint-detection of SIMS, the termination of the flattening process can be very easily and precisely managed. As an etching rate of GCIB is very low, it is difficult to flatten the insulation film until the upper surface of the MR multi-layered structure  82  is exposed by executing GCIB only. 
     FIGS. 9 a  to  9   h  illustrate a part of a fabrication process of a TMR head or a CPP-GMR head as a still further embodiment according to the present invention. 
     First, as shown in FIG. 9 a,  a lower electrode film  91  which also functions as a magnetic shield film and a MR multi-layered film  92 ′ are sequentially deposited on an insulation film  90  formed on a substrate (not shown). 
     Then, a photo-resist pattern  93  with a straight shaped side wall is formed thereon as shown in FIG. 9 b.    
     Then, the MR multi-layered film  92 ′ is patterned by IBE, RIE, RIBE or sputtering using the photo-resist pattern  93  as a mask to obtain a MR multi-layered structure  92  as shown in FIG. 9 c.  The upper surface of this MR multi-layered structure  92  operates as a junction. 
     The MR multi-layered structure  92  may be for example a TMR multi-layered structure, a CPP-GMR multi-layered structure, a TMR or CPP-GMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer, a CPP-GMR multi-layered structure with an anti-ferromagnetic coupling type magnetic films, a CPP-GMR multi-layered structure with a specular type spin-valve magnetic films, or a CPP-GMR multi-layered structure with a dual spin-valve type magnetic films. 
     Then, after the photo-resist pattern  93  used as a mask is removed, an insulation film  94 ′″ is deposited on the entire surface as shown in FIG. 9 d.  Thus, the insulation film  94 ′″ is protruded at the junction. In order to ensure reliable electrical insulation, it is desired that the thickness of this insulation film  94 ′″ is determined to a value equal to or thicker than that of the MR multi-layered structure  92 . 
     Thereafter, as shown in FIG. 9 e,  the insulation film  94 ′″ is flattened by executing a low angle IBE using a beam having a low incident angle with surfaces of laminated layers, and thus a flattened insulation film  94 ″ is obtained. 
     In this case, it is preferred that an angle of the incident ion beam of the low angle IBE with the surfaces of laminated layers is 0-40 degrees. If this angle of the incident ion beam is more than 40 degrees, the flattening of the insulation film becomes difficult. The angle of the incident ion beam of the low angle IBE with the surfaces of laminated layers is more preferably 0-30 degrees, and most preferably 0-20 degrees. 
     Termination of the flattening may be managed by monitoring a flattening process time. 
     Etching conditions of an example of the low angle IBE are as follows: 
     Beam incident angle: 20 degrees; 
     Acceleration voltage: 300 V; 
     Beam current: 0.35 mA/cm 2 ; 
     Ar gas pressure: 2.4×10 −4  Torr; 
     Substrate temperature: 30° C.; 
     Etching time: about 12 minutes. 
     Thereafter, as shown in FIG. 9 f,  the insulation film  94 ″ is flattened by executing a GCIB, and thus a flattened insulation film  94 ′ is obtained. This flattening is stopped before at least the upper surface or junction of the MR multi-layered structure  92  is exposed or appeared. 
     The flattening process using GCIB consists of producing gas clusters by ejecting a gas such as Ar gas into a high vacuum environment and rapidly cooling the gas, and bumping the produced gas clusters against a surface of an object so as to flatten the surface. 
     Termination of the flattening may be managed by monitoring a flattening process time. 
     Flattening conditions of an example of the GCIB are as follows: 
     Acceleration voltage: 15 kV; 
     Dose amount: 1×11 16  ions/cm 2 . 
     Then, as shown in FIG. 9 g,  the insulation film  94 ′ is flattened until at least the upper surface or junction of the MR multi-layered structure  92  is exposed or appeared by executing a low rate IBE with a low etching rate such as an etching rate of 2 nm/min or less for etching of SiO 2 , and thus a flattened insulation film  94  is obtained. 
     Termination of the latter flattening may be managed by monitoring a flattening process time or by executing an endpoint-detection process using a SIMS. In the latter case, because of a very small top surface area of the MR multi-layered structure  92 , it is desired to laminate a film specifically used for endpoint detection using the SIMS in order to easily perform the endpoint-detection process. Concretely, the insulation film  94 ′″ is deposited to a height equal to or somewhat lower than that of the MR multi-layered structure  92 , then an extremely thin film specially used for endpoint detection is deposited, and thereafter the insulation film  94 ′″ is again deposited thereon to make the endpoint detection process easier. 
     Etching conditions of an example of the low rate IBE are as follows: 
     Beam incident angle: 90 degrees; 
     Acceleration voltage: 250 V; 
     Beam current: 0.1 mA/cm 2 ; 
     Ar gas pressure: 2×10 −4  Torr; 
     Substrate temperature: 50° C.; 
     Etching time: about 15 minutes. 
     After that, an upper electrode film  95  which also functions as a magnetic shield film is deposited on the flattened insulation film  94  and the MR multi-layered structure  92  as shown in FIG. 9 h.    
     A hard mask may be used instead of the photo-resist pattern  93 . When a conductive hard mask is used, this hard mask may be remained without removing and used as a part of a cap layer of the MR multi-layered structure  92 . 
     Thickness and material of each film or each layer in this embodiment are the same as those in the embodiment of FIGS. 3 a - 3   f.  Also, configuration of the MR multi-layered structure  92  is the same as that of the MR multi-layered structure  32  in the embodiment of FIGS. 3 a - 3   f.    
     As aforementioned, according to this embodiment, the insulation film  94 ′″ is deposited on the MR multi-layered structure  92  and the lower electrode film  81 , then this insulation film  94 ′″ is flattened using the low angle IBE and GCIB to a certain extent, and thereafter the insulation film  94 ′ is flattened by the low rate IBE using endpoint-detection of SIMS until at least the upper surface of the MR multi-layered structure  92  is exposed to form a flattened insulation film  94  on and around the MR multi-layered structure  92 . 
     Since a resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using a lift-off method can be formed. Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure  92 , a very precise shape of the MR multi-layered structure  92  can be expected. Furthermore, because no burr nor overlap of the insulation film  94  will occur and thus a very strict track width can be defined, it is possible to easily fabricate a TMR element or GMR element with an extremely narrow track width of 200 nm or less. In fact, a TMR element with a track width of 100 nm and good output characteristics could be fabricated according to this embodiment. 
     In addition, according to this embodiment, since the upper surface of the MR multi-layered structure  92  is exposed by the low rate IBE using endpoint-detection of SIMS, the termination of the flattening process can be very easily and precisely managed. As an etching rate of GCIB is very low, it is difficult to flatten the insulation film until the upper surface of the MR multi-layered structure  92  is exposed by executing GCIB only. 
     FIGS. 10 a  to  10   f  illustrate a part of a fabrication process of a TMR head or a CPP-GMR head as a further embodiment according to the present invention. 
     First, as shown in FIG. 10 a,  a lower electrode film  101  which also functions as a magnetic shield film and a MR multi-layered film  102 ′ are sequentially deposited on an insulation film  100  formed on a substrate (not shown). 
     Then, a photo-resist pattern  103  with a straight shaped side wall is formed thereon as shown in FIG. 10 b.    
     Then, the MR multi-layered film  102 ′ is patterned by IBE, RIE, RIBE or sputtering using the photo-resist pattern  103  as a mask to obtain a MR multi-layered structure  102  as shown in FIG. 10 c.  The upper surface of this MR multi-layered structure  102  operates as a junction. 
     The MR multi-layered structure  102  may be for example a TMR multi-layered structure, a CPP-GMR multi-layered structure, a TMR or CPP-GMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer, a CPP-GMR multi-layered structure with an anti-ferromagnetic coupling type magnetic films, a CPP-GMR multi-layered structure with a specular type spin-valve magnetic films, or a CPP-GMR multi-layered structure with a dual spin-valve type magnetic films. 
     Then, after the photo-resist pattern  103  used as a mask is removed, an insulation film  104 ′ is deposited on the entire surface as shown in FIG. 10 d.  Thus, the insulation film  104 ′ is protruded at the junction. In order to ensure reliable electrical insulation, it is desired that the thickness of this insulation film  104 ′ is determined to a value equal to or thicker than that of the MR multi-layered structure  102 . 
     Thereafter, as shown in FIG. 10 e,  the insulation film  104 ′ is flattened until at least the upper surface or junction of the MR multi-layered structure  102  is exposed or appeared by executing a precise CMP, and thus a flattened insulation film  104  and the MR multi-layered structure  102  with the appeared upper surface are obtained. 
     The precise CMP is a process of more precisely controlled CMP than a normal CMP process. In the precise CMP process, a dry or wet CMP remaining a low height difference is executed and a low lapping rate of 50 nm/min or less, preferably of 20 nm/min or less, more preferably of 10 nm/min or less is used. If the lapping rate exceeds 50 nm/min, a precise CMP will become difficult to perform. 
     For this purpose, a slurry consisting of one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite, or of a mixture containing one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite may be additionally used. The slurry has an average particle diameter of 100 nm or less, preferably 50 nm or less, more preferably 10 nm or less. If the average particle diameter of the slurry exceeds 100 nm, a precise CMP will become difficult to perform. A rotational speed of a rotation table is 1 to 10,000 rpm. If the rotational speed is less than 1 rpm, because of too low lapping rate, a productivity will decrease. Contrary to this, if the rotational speed exceeds 10,000 rpm, a precise CMP will become difficult to perform. 
     Termination of the flattening may be managed by monitoring a flattening process time. 
     After that, an upper electrode film  105  which also functions as a magnetic shield film is deposited on the flattened insulation film  104  and the MR multi-layered structure  102  as shown in FIG. 10 f.    
     A hard mask may be used instead of the photo-resist pattern  103 . When a conductive hard mask is used, this hard mask may be remained without removing and used as a part of a cap layer of the MR multi-layered structure  102 . 
     Thickness and material of each film or each layer in this embodiment are the same as those in the embodiment of FIGS. 3 a - 3   f.  Also, configuration of the MR multi-layered structure  102  is the same as that of the MR multi-layered structure  32  in the embodiment of FIGS. 3 a - 3   f.    
     As aforementioned, according to this embodiment, the insulation film  104 ′ is deposited on the MR multi-layered structure  102  and the lower electrode film  101 , then this insulation film  104 ′ is flattened by a precise CMP until at least the upper surface of the MR multi-layered structure  102  is exposed to form a flattened insulation film  104  on and around the MR multi-layered structure  102 . 
     Since a resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using a lift-off method can be formed. Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure  102 , a very precise shape of the MR multi-layered structure  102  can be expected. Furthermore, because no burr nor overlap of the insulation film  104  will occur and thus a very strict track width can be defined, it is possible to easily fabricate a TMR element or GMR element with an extremely narrow track width of 200 nm or less. In fact, a TMR element with a track width of 100 nm and good output characteristics could be fabricated according to this embodiment. 
     When the insulation film  104 ′ is deposited, a recess may be produced around the MR multi-layered structure  102 . Thus, a part of the deposited upper electrode film  105  will enter the recess and a magnetic field passing through this electrode film part will be applied to the MR multi-layered structure  102  causing its MR characteristics to deteriorate. However, according to this embodiment, since the recess is removed by CMP, it is possible to improve MR characteristics. 
     FIGS. 11 a  to  11   h  illustrate a part of a fabrication process of a TMR head or a CPP-GMR head as a still further embodiment according to the present invention. 
     First, as shown in FIG. 11 a,  a lower electrode film  111  which also functions as a magnetic shield film and a MR multi-layered film  112 ′ are sequentially deposited on an insulation film  110  formed on a substrate (not shown). 
     Then, a photo-resist pattern  113  with a straight shaped side wall is formed thereon as shown in FIG. 11 b.    
     Then, the MR multi-layered film  112 ′ is patterned by IBE, RIE, RIBE or sputtering using the photo-resist pattern  113  as a mask to obtain a MR multi-layered structure  112  as shown in FIG. 11 c.  The upper surface of this MR multi-layered structure  112  operates as a junction. 
     The MR multi-layered structure  112  may be for example a TMR multi-layered structure, a CPP-GMR multi-layered structure, a TMR or CPP-GMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer, a CPP-GMR multi-layered structure with an anti-ferromagnetic coupling type magnetic films, a CPP-GMR multi-layered structure with a specular type spin-valve magnetic films, or a CPP-GMR multi-layered structure with a dual spin-valve type magnetic films. 
     Then, after the photo-resist pattern  113  used as a mask is removed, an insulation film  114 ″ is deposited on the entire surface as shown in FIG. 11 d.  Thus, the insulation film  114 ″ is protruded at the junction. In order to ensure reliable electrical insulation, it is desired that the thickness of this insulation film  114 ″ is determined to a value equal to or thicker than that of the MR multi-layered structure  112 . 
     Then, as shown in FIG. 11 e,  a photo-resist pattern  116  with an opening  116   a  located at a contact hole is formed on the insulation film  114 ″. 
     Then, as shown in FIG. 11 f,  the insulation film  114 ″ is patterned using the photo-resist pattern  116  as a mask by ion milling to obtain an insulation film  114 ′ provided with a contact hole  114   a ′ on the MR multi-layered structure  112 , and thereafter the photo-resist pattern  116  is removed. 
     Thereafter, as shown in FIG. 11 g,  the insulation film  114 ′ is flattened until at least the upper surface or junction of the MR multi-layered structure  112  is exposed or appeared by executing a precise CMP, and thus a flattened insulation film  114  and the MR multi-layered structure  112  with the appeared upper surface are obtained. 
     The precise CMP is a process of more precisely controlled CMP than a normal CMP process. In the precise CMP process, a dry or wet CMP remaining a low height difference is executed and a low lapping rate of 50 nm/min or less, preferably of 20 nm/min or less, more preferably of 10 nm/min or less is used. If the lapping rate exceeds 50 nm/min, a precise CMP will become difficult to perform. 
     For this purpose, a slurry consisting of one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite, or of a mixture containing one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite may be additionally used. The slurry has an average particle diameter of 100 nm or less, preferably 50 nm or less, more preferably 10 nm or less. If the average particle diameter of the slurry exceeds 100 nm, a precise CMP will become difficult to perform. A rotational speed of a rotation table is 1 to 10,000 rpm. If the rotational speed is less than 1 rpm, because of too low lapping rate, a productivity will decrease. Contrary to this, if the rotational speed exceeds 10,000 rpm, a precise CMP will become difficult to perform. 
     Termination of the flattening may be managed by monitoring a flattening process time. 
     After that, an upper electrode film  115  which also functions as a magnetic shield film is deposited on the flattened insulation film  114  and the MR multi-layered structure  112  as shown in FIG. 11 h.    
     A hard mask may be used instead of the photo-resist pattern  113 . When a conductive hard mask is used, this hard mask may be remained without removing and used as a part of a cap layer of the MR multi-layered structure  112 . 
     Thickness and material of each film or each layer in this embodiment are the same as those in the embodiment of FIGS. 3 a - 3   f.  Also, configuration of the MR multi-layered structure  112  is the same as that of the MR multi-layered structure  32  in the embodiment of FIGS. 3 a - 3   f.    
     As aforementioned, according to this embodiment, the insulation film  114 ″ is deposited on the MR multi-layered structure  112  and the lower electrode film  111 , then a contact hole is formed on this insulation film  114 ″, and thereafter the insulation film  114 ′ is flattened by a precise CMP until at least the upper surface of the MR multi-layered structure  112  is exposed to form a flattened insulation film  114  on and around the MR multi-layered structure  112 . 
     Since a resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using a lift-off method can be formed. Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure  112 , a very precise shape of the MR multi-layered structure  112  can be expected. Furthermore, because no burr nor overlap of the insulation film  114  will occur and thus a very strict track width can be defined, it is possible to easily fabricate a TMR element or GMR element with an extremely narrow track width of 200 nm or less. In fact, a TMR element with a track width of 100 nm and good output characteristics could be fabricated according to this embodiment. 
     When the insulation film  114 ″ is deposited, a recess may be produced around the MR multi-layered structure  112 . Thus, a part of the deposited upper electrode film  115  will enter the recess and a magnetic field passing through this electrode film part will be applied to the MR multi-layered structure  112  causing its MR characteristics to deteriorate. However, according to this embodiment, since the recess is removed by CMP, it is possible to improve MR characteristics. 
     In general, if protruded portions of the insulation film to be lapped by CMP have different sizes with each other, lapping conditions of CMP will become very severe and thus a dishing phenomenon where a part of the insulation film located in recess portions is never flattened but grown concave or a thinning phenomenon where the insulation film itself is unnecessarily thinned may occur. In order to prevent such phenomena from occurrence, it is preferred that center portions of the protrude portions are removed in different sizes by photo-milling to form contact holes with different diameters. As a result, substantial sizes of the protruded portions after milling become nearly equal and therefore a margin in lapping conditions of CMP increases. 
     A part of the fabrication process according to this embodiment is the same as a part of the contact-hole method. However, the fabrication process of this embodiment quite differs from that of the contact-hole method in that, after making contact holes, a part of the insulation film overlapped on the upper surface of the MR multi-layered structure  112  is completely removed by the CMP lapping process. 
     FIGS. 12 a  to  12   g  illustrate a part of a fabrication process of a TMR head or a CPP-GMR head as a still more further embodiment according to the present invention. 
     First, as shown in FIG. 12 a,  a lower electrode film  121  which also functions as a magnetic shield film and a MR multi-layered film  122 ′ are sequentially deposited on an insulation film  120  formed on a substrate (not shown). 
     Then, a photo-resist pattern  123  with a straight shaped side wall is formed thereon as shown in FIG. 12 b.    
     Then, the MR multi-layered film  122 ′ with a thickness of about 35-55 nm is patterned by IBE, RIE, RIBE or sputtering using the photo-resist pattern  123  as a mask to obtain a MR multi-layered structure  122  as shown in FIG. 12 c . The upper surface of this MR multi-layered structure  122  operates as a junction. 
     The MR multi-layered structure  122  may be for example a TMR multi-layered structure, a CPP-GMR multi-layered structure, a TMR or CPP-GMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer, a CPP-GMR multi-layered structure with an anti-ferromagnetic coupling type magnetic films, a CPP-GMR multi-layered structure with a specular type spin-valve magnetic films, or a CPP-GMR multi-layered structure with a dual spin-valve type magnetic films. 
     Then, while the photo-resist pattern  123  used as a mask is remained without removing, an insulation film  124 ′ made of Al 2 O 3  or SiO 2  for example with a thickness of about 50-100 nm is deposited on the entire surface as shown in FIG. 12 d.  Thus, the insulation film  124 ′ is protruded at the junction. In order to ensure reliable electrical insulation, it is desired that the thickness of this insulation film  124 ′ is determined to a value equal to or thicker than that of the MR multi-layered structure  122 . 
     Thereafter, as shown in FIG. 12 e,  the insulation film  124 ′ is lapped until a part of the photo-resist pattern  123  on the upper surface or junction of the MR multi-layered structure  122  remains by executing a precise CMP, and thus an insulation film  124  is obtained. 
     The precise CMP is a process of more precisely controlled CMP than a normal CMP process. In the precise CMP process, a dry or wet CMP remaining a low height difference is executed and a low lapping rate of 50 nm/min or less, preferably of 20 nm/min or less, more preferably of 10 nm/min or less is used. If the lapping rate exceeds 50 nm/min, a precise CMP will become difficult to perform. 
     For this purpose, a slurry consisting of one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite, or of a mixture containing one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite may be additionally used. The slurry has an average particle diameter of 100 nm or less, preferably 50 nm or less, more preferably 10 nm or less. If the average particle diameter of the slurry exceeds 100 nm, a precise CMP will become difficult to perform. A rotational speed of a rotation table is 1 to 10,000 rpm. If the rotational speed is less than 1 rpm, because of too low lapping rate, a productivity will decrease. Contrary to this, if the rotational speed exceeds 10,000 rpm, a precise CMP will become difficult to perform. 
     Termination of the lapping may be managed by monitoring a lapping process time. 
     Then, as shown in FIG. 12 f,  the remained part of the photo-resist pattern  123 ′ is removed by a solvent. 
     After that, an upper electrode film  125  which also functions as a magnetic shield film is deposited on the insulation film  124  and the MR multi-layered structure  122  as shown in FIG. 12 g.    
     A hard mask may be used instead of the photo-resist pattern  123 . When a conductive hard mask is used, this hard mask may be remained without removing and used as a part of a cap layer of the MR multi-layered structure  122 . 
     Configuration of the MR multi-layered structure  122  is the same as that of the MR multi-layered structure  32  in the embodiment of FIGS. 3 a - 3   f.  Namely, the layer structure of this TMR head is the same as that shown in FIG.  5 . 
     The cap layer  122   f  is preferably made of one of tantalum, rhodium, ruthenium, osmium, tungsten, palladium, platinum and gold, or an alloy containing one of tantalum, rhodium, ruthenium, osmium, tungsten, palladium, platinum and gold. 
     As aforementioned, according to this embodiment, the insulation film  124 ′ is deposited on the MR multi-layered structure  122  and the lower electrode film  121  without removing the photo-resist pattern  123  used as a mask but remaining whole of it, then the deposited insulation film  124 ′ is lapped by a precise CMP until a part of the photo-resist pattern  123  located on the upper surface of the MR multi-layered structure  102  remains, and the insulation film  124  on and around the MR multi-layered structure  122  is obtained by removing the remained part of the photo-resist pattern  123 . 
     Since a resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using a lift-off method can be formed. Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure  102 , a very precise shape of the MR multi-layered structure  102  can be expected. Furthermore, because no burr nor overlap of the insulation film  124  will occur and thus a very strict track width can be defined, it is possible to easily fabricate a TMR element or GMR element with an extremely narrow track width of 200 nm or less. In concrete, a TMR element with a track width of 100 nm and good output characteristics can be fabricated according to this embodiment. 
     When the insulation film  124 ′ is deposited, a recess may be produced around the MR multi-layered structure  122 . Thus, a part of the deposited upper electrode film  125  will enter the recess and a magnetic field passing through this electrode film part will be applied to the MR multi-layered structure  122  causing its MR characteristics to deteriorate. However, according to this embodiment, since the recess is removed by CMP, it is possible to improve MR characteristics. 
     In most cases, termination of a CMP process is managed by monitoring a lapping process time. As for a precise CMP process, it is necessary to perform this termination management in an extremely precise manner. In this embodiment, in order to more easily execute this termination management, the insulation film  124 ′ is deposited without removing the photo-resist pattern  123  after the milling process, then the deposited insulation film  124 ′ is lapped by the CMP until a part of the photo-resist pattern  123  remains, and thereafter the remained photo-resist is removed by a solvent. Therefore, according to this embodiment, the CMP process may be terminated at an arbitrary time before a part of the photo-resist pattern  123  remains. In other words, this embodiment will allow a rough termination management. 
     FIGS. 13 a  to  13   h  illustrate a part of a fabrication process of a TMR head or a CPP-GMR head as a further embodiment according to the present invention. 
     First, as shown in FIG. 13 a , a lower electrode film  131  which also functions as a magnetic shield film, a MR multi-layered film  132 ′ and a CMP stop film  136 ′ are sequentially deposited on an insulation film  130  formed on a substrate (not shown). 
     The CMP stop film  136 ′ is made of a material that is harder to be lapped than materials to be lapped by CMP. By using such CMP stop film, because the lapping rate will extremely decrease and thus the lapping will substantially stop, or a necessary torque for lapping will suddenly increase, due to exposure of the CMP stop film during the CMP process, it is possible to know when the CMP process should be terminated. For example, in case that the insulation film  134 ′ is SiO 2 , Al 2 O 3  that has a lower lapping rate than SiO 2  is used as the CMP stop film  136 ′. In case that Al 2 O 3  is used as the insulation film  134 ′, DLC that has a lower lapping rate than Al 2 O 3  is used as the CMP stop film  136 ′. 
     Then, a photo-resist pattern  133  with a straight shaped side wall is formed thereon as shown in FIG. 13 b.    
     Then, the CMP stop film  136 ′ and the MR multi-layered film  132 ′ are patterned by IBE, RIE, RIBE or sputtering using the photo-resist pattern  133  as a mask to obtain a CMP stop film  136  and a MR multi-layered structure  132  as shown in FIG. 13 c.  The upper surface of this MR multi-layered structure  132  operates as a junction. 
     The MR multi-layered structure  132  may be for example a TMR multi-layered structure, a CPP-GMR multi-layered structure, a TMR or CPP-GMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer, a CPP-GMR multi-layered structure with an anti-ferromagnetic coupling type magnetic films, a CPP-GMR multi-layered structure with a specular type spin-valve magnetic films, or a CPP-GMR multi-layered structure with a dual spin-valve type magnetic films. 
     Then, the photo-resist pattern  133  used as a mask is removed as shown in FIG. 13 d.    
     Then, an insulation film  134 ′ is deposited on the entire surface. Thus, the insulation film  134 ′ is protruded at the junction. Furthermore, as shown in FIG. 13 e,  a CMP stop film  137 ′ is deposited on the entire surface of the insulation film  134 ′. This CMP stop film  137 ′ is formed to augment functions of the CMP stop film  136 ′, so that the upper surface thereof is substantially equal to the level of the upper surface of the CMP stop film  136 ′. A material of this CMP stop film  137 ′ is the same as that of the CMP stop film  136 ′. 
     Thereafter, as shown in FIG. 13 f,  the insulation film  134 ′ above the upper surface or junction of the MR multi-layered structure  132  is lapped and removed until the CMP stop film  134 ′ is exposed or appeared by executing a precise CMP. 
     The precise CMP is a process of more precisely controlled CMP than a normal CMP process. In the precise CMP process, a dry or wet CMP remaining a low height difference is executed and a low lapping rate of 50 nm/min or less, preferably of 20 nm/min or less, more preferably of 10 nm/min or less is used. If the lapping rate exceeds 50 nm/min, a precise CMP will become difficult to perform. 
     For this purpose, a slurry consisting of one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite, or of a mixture containing one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite may be additionally used. The slurry has an average particle diameter of 100 nm or less, preferably 50 nm or less, more preferably 10 nm or less. If the average particle diameter of the slurry exceeds 100 nm, a precise CMP will become difficult to perform. A rotational speed of a rotation table is 1 to 10,000 rpm. If the rotational speed is less than 1 rpm, because of too low lapping rate, a productivity will decrease. Contrary to this, if the rotational speed exceeds 10,000 rpm, a precise CMP will become difficult to perform. 
     Termination of this lapping process may be managed by monitoring a flattening process time. 
     Then, as shown in FIG. 13 g,  the CMP stop films  136  and  137 ′ are removed by IBE, RIE, RIBE or sputtering. 
     After that, an upper electrode film  135  which also functions as a magnetic shield film is deposited on the flattened insulation film  134  and the MR multi-layered structure  132  as shown in FIG. 13 h.    
     A hard mask may be used instead of the photo-resist pattern  133 . When a conductive hard mask is used, this hard mask may be remained without removing and used as a part of a cap layer of the MR multi-layered structure  132 . 
     It is desired that a selective lapping ratio between the CMP stop films  136  and  137 ′ and the insulation film  134 ′ for CMP is four or more. 
     Thickness and material of each film or each layer in this embodiment are the same as those in the embodiments of FIGS. 3 a - 3   f  and FIGS. 12 a - 12   g.    
     As aforementioned, according to this embodiment, the CMP stop films  136  and  137 ′ are deposited on the MR multi-layered structure  132  and the insulation film  134 ′, then the CMP stop film  137 ′ and the insulation film  134 ′ on the junction of the MR multi-layered structure  132  are lapped by a precise CMP until the CMP stop film  136  is exposed, and thereafter the CMP stop films  136  and  137  are removed to form an insulation film  134  on and around the MR multi-layered structure  132 . 
     Since a resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using a lift-off method can be formed. Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure  132 , a very precise shape of the MR multi-layered structure  132  can be expected. Furthermore, because no burr nor overlap of the insulation film  134  will occur and thus a very strict track width can be defined, it is possible to easily fabricate a TMR element or GMR element with an extremely narrow track width of 200 nm or less. Concretely, a TMR element with a track width of 100 nm and good output characteristics can be fabricated according to this embodiment. 
     When the insulation film  134 ′ is deposited, a recess may be produced around the MR multi-layered structure  132 . Thus, a part of the deposited upper electrode film  135  will enter the recess and a magnetic field passing through this electrode film part will be applied to the MR multi-layered structure  132  causing its MR characteristics to deteriorate. However, according to this embodiment, since the recess is removed by CMP, it is possible to improve MR characteristics. 
     Particularly, according to this embodiment, since the CMP stop films  136  and  137 ′ are used for the CMP process, a uniformity in the lapping amount on a wafer can be assured. 
     FIGS. 14 a  to  14   g  illustrate a part of a fabrication process of a TMR head or a CPP-GMR head as a still further embodiment according to the present invention. 
     First, as shown in FIG. 14 a,  a lower electrode film  141  which also functions as a magnetic shield film, a MR multi-layered film  142 ′ and a milling stop film  147 ′ are sequentially deposited on an insulation film  140  formed on a substrate (not shown). 
     Then, a photo-resist pattern  143  with a straight shaped side wall is formed thereon as shown in FIG. 14 b.    
     Then, the milling stop film  147 ′ and the MR multi-layered film  142 ′ are patterned by IBE, RIE, RIBE or sputtering using the photo-resist pattern  143  as a mask to obtain a milling stop film  147  and a MR multi-layered structure  142  as shown in FIG. 14 c.  The upper surface of this MR multi-layered structure  142  operates as a junction. 
     The milling stop film  147 ′ is made of a material that is not contained in the films to be milled and has a high sensitivity so as to be easily detected. Thus, a transition element is preferable for the material. More concretely, the milling stop film  147 ′ may be made of one of cobalt, tantalum, rhodium, ruthenium, osmium, tungsten, palladium, platinum and gold, or an alloy containing one of cobalt, tantalum, rhodium, ruthenium, osmium, tungsten, palladium, platinum and gold. 
     The MR multi-layered structure  142  may be for example a TMR multi-layered structure, a CPP-GMR multi-layered structure, a TMR or CPP-GMR multi-layered structure with a bias layer for defining a magnetization direction of a free layer, a CPP-GMR multi-layered structure with an anti-ferromagnetic coupling type magnetic films, a CPP-GMR multi-layered structure with a specular type spin-valve magnetic films, or a CPP-GMR multi-layered structure with a dual spin-valve type magnetic films. 
     Then, as shown in FIG. 14 d,  an insulation film  144 ″ is deposited on the entire surface. Thus, the insulation film  144 ″ is protruded at the junction. 
     Thereafter, as shown in FIG. 14 e,  a part of the insulation film  144 ″ above the upper surface or junction of the MR multi-layered structure  142  is lapped and removed by executing a precise CMP. This lapping and removing is stopped before the upper surface or junction of the MR multi-layered structure  142  is exposed or appeared. 
     The precise CMP is a process of more precisely controlled CMP than a normal CMP process. In the precise CMP process, a dry or wet CMP remaining a low height difference is executed and a low lapping rate of 50 nm/min or less, preferably of 20 nm/min or less, more preferably of 10 nm/min or less is used. If the lapping rate exceeds 50 nm/min, a precise CMP will become difficult to perform. 
     For this purpose, a slurry consisting of one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite, or of a mixture containing one of colloidal silica, cerium oxide, corundum, boron nitride, diamond, chromium oxide, iron oxide, fumed silica, alumina and zeolite may be additionally used. The slurry has an average particle diameter of 100 nm or less, preferably 50 nm or less, more preferably 10 nm or less. If the average particle diameter of the slurry exceeds 100 nm, a precise CMP will become difficult to perform. A rotational speed of a rotation table is 1 to 10,000 rpm. If the rotational speed is less than 1 rpm, because of too low lapping rate, a productivity will decrease. Contrary to this, if the rotational speed exceeds 10,000 rpm, a precise CMP will become difficult to perform. 
     Termination of this CMP process may be managed by monitoring a flattening process time. 
     Then, as shown in FIG. 14 f,  the insulation film  144 ′ on the milling stop film  147  is removed by IBE, RIE, RIBE or sputtering. The milling stop film  147  is not removed but remained. Termination of this milling process may be managed by using a SIMS. 
     After that, an upper electrode film  145  which also functions as a magnetic shield film is deposited on the insulation film  144  and the milling stop film  147  as shown in FIG. 14 g.    
     A hard mask may be used instead of the photo-resist pattern  143 . 
     Thickness and material of each film or each layer in this embodiment are the same as those in the embodiments of FIGS. 3 a - 3   f  and FIGS. 12 a - 12   g.    
     As aforementioned, according to this embodiment, the milling stop film  147  is deposited on the MR multi-layered structure  142 , then the insulation film  144 ′ on the junction of the MR multi-layered structure  142  is lapped by a precise CMP. This precise CMP is stopped before the upper surface or junction of the MR multi-layered structure  142  is exposed or appeared, and thereafter the remaining insulation film is removed by milling to form an insulation film  144  on and around the MR multi-layered structure  142 . 
     Since a resist pattern or a hard mask with a straightly shaped side surface but no inversely tapered side surface can be used according to this method, more a finely micromachined MR multi-layered structure than that fabricated by using a lift-off method can be formed. Also, since an RIE method or a hard mask that will prevent widening of the bottom of the MR multi-layered structure can be utilized for milling the MR multi-layered structure  142 , a very precise shape of the MR multi-layered structure  142  can be expected. Furthermore, because no burr nor overlap of the insulation film  144  will occur and thus a very strict track width can be defined, it is possible to easily fabricate a TMR element or GMR element with an extremely narrow track width of 200 nm or less. Concretely, a TMR element with a track width of 100 nm and good output characteristics can be fabricated according to this embodiment. 
     When the insulation film  144 ″ is deposited, a recess may be produced around the MR multi-layered structure  142 . Thus, a part of the deposited upper electrode film  145  will enter the recess and a magnetic field passing through this electrode film part will be applied to the MR multi-layered structure  132  causing its MR characteristics to deteriorate. However, according to this embodiment, since the recess is removed by CMP, it is possible to improve MR characteristics. 
     In most cases, termination of a CMP process is managed by monitoring a lapping process time. As for a precise CMP process, it is necessary to perform this termination management in an extremely precise manner. In this embodiment, in order to more easily execute this termination management, the milling stop film  147  is deposited on the junction, then the insulation film  144 ′ is lapped by the CMP to its middle position, and thereafter the remained insulation film  144 ′ is removed by milling until the milling stop film  147  is exposed or appeared. Therefore, according to this embodiment, the CMP process may be terminated at an arbitrary time before a part of the insulation film  144 ′ remains. In other words, this embodiment will allow a rough termination management. 
     Many widely different embodiments of the present invention may be constructed without departing from the spirit and scope of the present invention. It should be understood that the present invention is not limited to the specific embodiments described in the specification, except as defined in the appended claims.