HK1144977B - Method and system for providing a perpendicular magnetic recording head - Google Patents

Description

Method and system for providing a perpendicular magnetic recording head

Background

FIG. 1 is a flow chart depicting one conventional method 10 of fabricating a conventional Perpendicular Magnetic Recording (PMR) transducer. Some steps are omitted for simplicity. The conventional method 10 is used to provide a PMR pole. An intermediate layer, a Chemical Mechanical Planarization (CMP) stop layer and a hard mask layer are provided, via step 12. The intermediate layer is typically alumina. The CMP stop layer may comprise ruthenium (Ru) and the hard mask layer may comprise nickel chromium (NiCr). A photoresist mask is provided over the hard mask layer, via step 14. The photoresist mask includes an opening over a portion of the intermediate layer in which the PMR pole is to be formed. Conventional openings are formed in the hard mask layer, via step 16. Typically, this is achieved by using conventional ion milling. Step 16 also includes forming conventional openings in the CMP stop layer. Thus, the pattern of the photoresist mask is transferred to the hard mask and CMP stop layer in a conventional manner by ion milling in step 16.

A trench is formed in the aluminum oxide layer using the hard mask and the photoresist mask, via step 18. Step 18 is typically performed using an alumina Reactive Ion Etch (RIE). It is desirable that the top of the trench is wider than the bottom of the trench. Additionally, the trench may extend through the aluminum oxide interlayer. Thus, the top surface of the PMR pole formed therein will be wider than its bottom. Thus, the sidewalls of the PMR pole have a reverse angle. A conventional PMR pole material is deposited, via step 20. Step 20 may include plating or sputtering the ferromagnetic pole material and seed layer(s) or seed layer(s). CMP is then performed, via step 22. The stop layer provided in step 12 is used to stop the CMP.

Bevel(s) may also be provided in the conventional PMR pole, via step 24. If a top bevel is to be provided, step 24 may include removing a top portion of the ferromagnetic pole material in the area of the Air Bearing Surface (ABS). Thus, the top surface of the conventional PMR pole near the ABS is lower than the yoke (yoke) portion of the PMR pole. If step 24 is used to form the bottom bevel, step 24 is generally performed earlier in method 10, for example, before step 20. In this case, step 24 may include masking a portion of the trench formed in step 18 and refilling the trench bottom near the ABS area. Thus, a bottom bevel can be formed. Thus, a conventional PMR pole is provided. Subsequent structures, such as write gaps and shields, may then be provided.

Although the conventional method 10 may provide a conventional PMR transducer, there may be disadvantages. The use of photoresist masks and hard masks can result in relatively large variations in the critical dimensions of conventional PMR poles. The critical dimension corresponds to the track width of a conventional PMR pole. Such variations in track width may adversely affect manufacturing and performance. In addition, conventional PMR poles may be relatively large in size. Using conventional photolithographic techniques, the critical diameter of the opening formed in step 16, and thus the trench provided in step 18, is typically greater than one hundred fifty nanometers. Thus, in this regard only, conventional PMR poles formed using the conventional method 10 may not be usable in high density magnetic recording techniques.

Accordingly, there is a need for an improved method of manufacturing a PMR transducer.

Disclosure of Invention

A method and system for providing a PMR pole in a magnetic recording sensor is disclosed. The method and system include providing a mask over the intermediate layer. The mask includes a line having at least one side. The method and system further include providing a hard mask layer over the mask. At least a portion of the hard mask is located on the side(s) of the line. The method and system further include removing at least a portion of the hard mask that is located on the side(s) of the line. Thereby, at least a portion of the wiring is exposed. The line is then removed. Thus, an opening is provided in the hard mask corresponding to the line. The method and system also include forming a trench in the intermediate layer below the opening. The trench has a bottom and a top wider than the bottom. The method and system further include providing a PMR pole, at least a portion of the PMR pole being located in the trench. In one aspect, the trench has a first width in the ABS area and a second width in the yoke area of the PMR pole. The first width is less than the second width. In this regard, a nonmagnetic layer may be deposited such that the ABS portion of the nonmagnetic layer on the bottom of the trench in the ABS area is thicker than the yoke portion of the nonmagnetic layer on the bottom of the trench in the yoke area. Thereby, a bottom slope can be formed.

Drawings

FIG. 1 is a flow chart depicting a conventional method of fabricating a PMR head.

FIG. 2 is a flow chart depicting an exemplary embodiment of a method of fabricating a PMR transducer.

FIG. 3 is a flow chart describing another embodiment of a method of fabricating a PMR transducer.

FIGS. 4-13 are diagrams depicting exemplary embodiments of a perpendicular magnetic recording transducer during fabrication.

Fig. 14 is a flow chart describing an exemplary embodiment of a method of manufacturing a magnetic pole.

FIGS. 15-22 are diagrams depicting an exemplary embodiment of a perpendicular magnetic recording transducer during fabrication.

Detailed Description

FIG. 2 is a flow chart describing an exemplary embodiment of a method 100 of manufacturing a PMR pole for a PMR transducer. Some steps are omitted for simplicity. The PMR transducer being fabricated may be part of a merged head that also includes a read head (not shown) and is located on a slider (not shown) in a disk drive. The method 100 may also begin after other portions of the PMR transducer are formed. The method 100 is also described in the context of providing a single PMR pole in a single magnetic recording transducer. However, the method 100 may be used to fabricate multiple transducers substantially simultaneously. The method 100 and system are also described in the context of a particular layer, such as a bottom anti-reflective coating (i.e., a BARC layer). However, in some embodiments, such a layer may comprise a plurality of sub-layers.

In one embodiment, the method 100 begins after the formation of the intermediate layer(s) where the PMR pole is located. In one embodiment, the intermediate layer is an insulator such as alumina. The middle layer may be located above the under-liner layer. Further, in one embodiment, the underlying layer may be an etch stop layer. A mask is provided on the intermediate layer, via step 102. The mask includes a line corresponding to the position of the PMR pole. In one embodiment, the mask is a photoresist mask and may be formed using photolithographic techniques. For example, a bottom anti-reflective coating (BARC) may be used in order to improve the formation of the lines. The BARC reduces reflections when a photoresist mask is formed over the BARC layer. In this embodiment, the formation of the mask may further include removing all BARCs exposed by the mask. A hard mask layer is provided on the mask, via step 104. For example, step 104 may include depositing a material such as nickel-chromium (NiCr), nickel-iron (NiFe), chromium (Cr), and/or ruthenium (Ru).

A portion of the hard mask layer is removed to expose the lines, via step 106. In one embodiment, the hard mask layer is removed by high angle ion milling. For example, in one embodiment, the ion milling is performed at an angle of at least seventy degrees and no more than ninety degrees from a normal to a surface of the transducer. In one such embodiment, the angle is at least seventy-seven degrees and no more than eighty-three degrees. Thereby, at least the portions of the hard mask layer on the sides of the lines are removed. Thereby, at least a part of the side of the wiring is exposed.

The lines in the mask are removed, via step 108. In one embodiment, step 106 includes performing lift-off of the wire. This stripping is possible because at least a portion of the line is exposed at step 106 and thus made accessible to the etchant used. Thereby forming a hard mask including openings corresponding to the lines. The openings in the hard mask are located substantially where occupied by the lines.

A trench is formed in the intermediate layer under the opening, via step 110. The trench has a bottom and a top wider than the bottom. Thus, the formed trench is suitable for a PMR pole. In one embodiment, the trench extends through the intermediate layer. However, in another embodiment, the trench may extend only partially through the intermediate layer. In one embodiment, step 110 includes performing a RIE.

The PMR pole is provided, via step 112. At least a portion of the PMR pole is located in the trench. In one embodiment, only a portion of the PMR pole is located within a trench in the intermediate layer. Thus, the top of the PMR pole will be higher than the top of the middle layer. In an alternative embodiment, the entire PMR pole is located within the trench. The forming of the PMR pole in step 112 may include providing one or more nonmagnetic layers in the trench. Such nonmagnetic layer(s) may be used to adjust the critical dimension of the PMR pole and the corresponding track width. In addition, seed layer(s) may also be provided. Thus, the PMR pole will be located above such nonmagnetic layer(s). In one embodiment, Atomic Layer Deposition (ALD) may be utilized to provide nonmagnetic layer(s) for track width adjustment. A planarization stop layer may also be provided as part of step 112. In one embodiment, a planarization stop layer is provided on the nonmagnetic layer(s). The planarization stop layer may be a CMP stop layer. In one such embodiment, the planarization stop layer comprises ruthenium (Ru). In another embodiment, the planarization stop layer may also serve as a seed layer. The layer(s) of the PMR pole may also be deposited uniformly. Planarization such as CMP may be performed. Additionally, the geometry of the PMR pole can be further tuned using ion beam etching. Top and/or bottom ramps may also be formed for the PMR pole. The bottom bevel may be formed by continuously filling the trench with nonmagnetic layer(s) such that the portion of the PMR pole near the ABS is higher than the portion of the PMR pole in the yoke region. After performing CMP, a top bevel may be formed by removing a portion of the PMR pole material. Thus, a PMR pole can be formed. Although described above as part of the formation of the PMR pole, at least some of the steps of providing the nonmagnetic layer, planarization stop layer, and/or seed layer may be considered separate from providing the PMR pole.

Using the method 100, at least a portion of a PMR transducer may be formed. The method 100 uses photoresist lines to provide openings in a hard mask. In one embodiment, the lines in the mask may have a critical dimension or width of no more than two hundred nanometers. The critical dimension of the lines may also not exceed one hundred nanometers. Thus, in one embodiment, the critical dimension of the PMR pole may not exceed two hundred nanometers. In another embodiment, the critical dimension may not exceed one hundred nanometers. The resulting PMR transducer can be used at higher densities. For example, the PMR transducer formed may be used as a 400Gb/in²(gigabits per square inch) or higher density transducers. Further, use of bottoms and/orThe top ramps may further concentrate the magnetic flux in a desired manner. Additionally, because lift-off of the traces may be performed at step 108, the fabrication of the PMR transducer may be simplified. Thus, using the method 100, PMR transducers can be manufactured that can be used at higher densities.

FIG. 3 is a flow chart depicting another exemplary embodiment of a method 150 of fabricating a PMR transducer. Some steps are omitted for simplicity. Fig. 4-13 are diagrams depicting an exemplary embodiment of the PMR transducer 200 from an ABS perspective during fabrication. For clarity, FIGS. 4-13 are not drawn to scale. Referring to fig. 3-13, the method 150 is described in the context of a PMR transducer 200. However, the method 150 may be used to form another device (not shown). The PMR transducer 200 as manufactured may be part of a merged head that also includes a read head (not shown) and is located on a slider (not shown) in a disk drive. The method 150 may also begin after other portions of the PMR transducer 200 are formed. The method 150 is also described in the context of providing a single PMR pole. However, the method 150 may be used to fabricate multiple transducers substantially simultaneously. The method 150 and apparatus 200 are also described in the context of a special layer, such as a bottom anti-reflective coating, or BARC layer. However, in some embodiments, such a layer may include multiple sub-layers.

An etch stop layer or underlayer is provided, via step 152. This layer can be used to terminate the alumina RIE. An intermediate layer is provided on the etch stop layer, via step 154. The intermediate layer is nonmagnetic and may be a dielectric layer, such as an aluminum oxide layer. A BARC is provided over the intermediate layer, via step 156. A photoresist mask is provided over the BARC, via step 158. The photoresist mask includes lines corresponding to the locations of the PMR poles. Fig. 4 depicts a portion of the PMR transducer 200 after step 158 is performed. In the illustrated embodiment, an underlying layer 202 is shown that may also serve as an etch stop layer 202. Additionally, an intermediate layer 204 is also depicted. BARC206 and mask 208 are also shown. In the illustrated embodiment, the mask 208 is comprised of wires. However, in another embodiment, the mask 208 may include other features. In addition, the mask 208 used may include a line for each PMR pole to be formed.

The pattern of mask 208 is transferred to BARC206, via step 160. Fig. 5 depicts the PMR transducer 200 after step 160 is performed. Thus, BARC 206' is located only under line 208. The remaining portion of the BARC layer 206 has been removed. A hard mask layer is provided on the PMR transducer 200, via step 162. Step 162 may include the placement of deposition materials such as nickel-chromium (NiCr), chromium (Cr), nickel-iron (NiFe), and/or ruthenium (Ru). Fig. 6 depicts the PMR transducer 200 after step 162 is performed. Thus, a hard mask layer 210 is provided.

An ion mill is performed at an angle to expose the lines of the mask 208, via step 164. In one embodiment, lapping is performed at a large angle from the surface normal of the PMR transducer 200. For example, in one embodiment, the angle may be at least seventy degrees and no more than ninety degrees. In another embodiment, the angle is at least seventy-seven degrees and no more than eighty-three degrees. In one embodiment, endpoint detection is used to control the amount of hard mask layer 210 removed from the sides of line 208. Fig. 7 depicts the PMR transducer after step 164 is performed. Thus, a hard mask layer 210' is formed from the hard mask layer 210. A portion 210' of the hard mask layer may remain on the mask 208. However, the sides of the lines of the mask 208 are at least partially exposed.

Stripping is performed, via step 166. Thereby, the remaining portion 208 of the line is removed. Additionally, the remaining portion 206' of the BARC under the lines is removed, via step 168. Fig. 8 depicts the PMR transducer 200 after step 168 is completed. Thus, an opening 212 is formed in hard mask 210'. The opening 212 exposes the underlying intermediate layer 204. The openings 212 correspond to the lines of the mask 208. Thus, the position and size of the opening 212 matches the position and size of the wiring.

A RIE is performed to form trenches in the intermediate layer 204, via step 170. In one embodiment, the RIE is performed with a chlorine-containing gas. Fig. 9 depicts the PMR transducer after step 170 is performed. Thus, a trench 213 is formed in the intermediate layer 204'. For clarity, the opening 212 is not marked again, but instead the trench 213 formed below the opening is marked. The trench 213 has a bottom and a top that is wider than the bottom.

The PMR pole is then formed. This may take many steps, such as steps 172 through 178. In one embodiment, at least one nonmagnetic layer is provided in the trench 213, via step 172. At least a portion of the nonmagnetic layer is located in the trench 213. In one embodiment, step 172 may include providing a track width adjusting layer and a seed layer. For example, the track width adjusting layer may be formed by depositing alumina using ALD. However, in another embodiment, another method and/or material for adjusting the layer to the track width may be used. The track width adjusting layer may be used to reduce the critical diameter of the formed magnetic pole, since it is magnetically separated from the formed magnetic pole. In other words, in one embodiment, the nonmagnetic layer may be viewed as making the width of the trench 213 smaller and shallower. Thus, the thickness of the nonmagnetic layer may be used to adjust the width and height of the PMR pole formed. In particular, the width of the PMR pole may be reduced by a factor of two the thickness of the nonmagnetic layer. In addition, the trench formed in step 168 may be configured to be thinner near the final location of the ABS than at the yoke region. In this embodiment, the trench 213 may be partially filled with nonmagnetic layer(s) in the ABS area. In this case, a bottom slope may be formed. In addition, a seed layer may be deposited on the track width adjusting layer. In some embodiments, the seed layer may also be a CMP stop layer. Alternatively, the hard mask layer 210' may be used as a stop layer. In another embodiment, the seed layer may be magnetic. Alternatively, step 172 may be omitted.

Fig. 10 depicts the PMR transducer 200 after step 172 is performed. Thus, the nonmagnetic layer 214 and the seed layer 216 are all visible. Each of the nonmagnetic track width adjusting layer 214 and a part of the seed layer 216 is located in the groove 213. However, another portion of each of the nonmagnetic layer 214 and the seed layer 216 may also be located over the hard mask 210 'and against the hard mask 210'. Thus, a portion of the nonmagnetic layer 214 is over the top of the intermediate layer 204'.

The PMR pole layer(s) may be provided, via step 174. Step 174 may include plating the PMR pole layer(s). In one embodiment, a single layer is used. However, in another embodiment, multiple layers may be used for the PMR pole. Thus, multiple layers may be deposited at step 174. In the described embodiment, the PMR pole layer(s) are uniformly deposited. However, in another embodiment, a mask may be used. In one embodiment, the PMR pole layer is plated on the planarization stop layer 216. In embodiments using a separate seed layer, the PMR pole layer may also be plated on the seed layer 218, and if employed, the nonmagnetic layer 214 may also be plated. Fig. 11 depicts the PMR transducer 200 after step 174 is performed. Thus, the PMR pole layer 220 is located in the trench 213. However, another portion of the PMR pole piece layer 220 may also be located on the hard mask 210 'and next to the hard mask 210'. Thus, a portion of the PMR pole layer 220 is on top of the middle layer 204'.

CMP or other selected planarization is performed, via step 176. CMP planarization may be terminated while at least a portion of the planarized hard mask 210' is still present. Fig. 12 depicts the PMR transducer 200 after step 176 is performed. Thus, the PMR pole 220' is formed from the PMR pole layer(s) 220. In addition, a portion of the seed layer 216 and the track width adjusting layer 214 is removed. Therefore, after step 176 is performed, only portions of the seed layer 216 'and the track width adjustment layer 214' remain. In addition, only a portion 210 "of the hard mask layer remains. In the illustrated embodiment, only a portion of the PMR pole 220' is present within the trench 213. This portion of the PMR pole 220' has a top that is wider than a bottom. In other words, the portions of the sidewalls of the PMR pole 220' have a negative angle (measured from the vertical). The remaining portion of the PMR pole 220 ' abuts the hard mask layer 210 ', the nonmagnetic layer 220, and the remaining planarization stop layer 222 '. The sidewalls of this portion of the PMR pole 220' are substantially vertical.

Additionally, a top ramp may optionally be provided at step 178. In one embodiment, step 178 would include masking the portion of the PMR pole 220' away from the ABS location area and removing the top portion of the PMR pole near the ABS location. Therefore, in the ABS area, the height of the PMR pole 220' will be lower. Thus, using the method 150, a bottom bevel, a top bevel, or both may be formed.

Fabrication of the PMR transducer 200 may then end. For example, write gaps, shields, and other structures may be provided. Fig. 13 depicts the PMR transducer 200 after these structures are provided. Thus, a write gap 222 and a top shield 224 are shown. In one embodiment, the write gap 222 may be an insulator, such as alumina. In another embodiment, other material(s) may be used.

Using the method 150, at least a portion of the PMR transducer 200 may be formed. Method 150 utilizes the photoresist lines of mask 208 to provide openings 212 in hard mask 210'. The line is exposed using ion milling, which can be better controlled using endpoint detection. Thus, peeling can be used to remove the wiring. The hard mask 210' may have sharper edges at the openings 212 because stripping may be performed. Thus, the edges of the PMR pole 220' may be better defined. In one embodiment, the lines in the mask 208' may have a critical dimension or width of no greater than two hundred nanometers. The critical dimension of the line 208 may also not exceed one hundred nanometers. Thus, in one embodiment, the 220' critical dimension of the PMR pole may not exceed two hundred nanometers. In another embodiment, the critical dimension may not exceed one hundred nanometers. The PMR transducer 200 can be used at higher densities. For example, the PMR transducer 200 may be used as a 400Gb/in²(gigabits per square inch) or higher density transducers. Thus, using the method 150, PMR transducers 200 can be manufactured that can be used at higher densities.

As described above, the PMR pole 220' may be provided with top and bottom slopes. Fig. 14 is a flow chart describing an exemplary embodiment of a method 250 of manufacturing a magnetic pole including a bevel(s). FIGS. 15-22 depict diagrams of exemplary embodiments of a perpendicular magnetic recording transducer 280 during manufacture. The transducer 280 may be part of a magnetic recording head that may also include a read transducer (not shown) and is located on a slider of a disk drive. The magnetic recording transducer 280 corresponds to the magnetic recording transducer 200. The method 250 is described in the context of a magnetic recording transducer 280. Referring to fig. 14-22, in method 250, some steps may be omitted or combined. In addition, FIGS. 15-22 are not drawn to scale for clarity. The method 250 is also described in the context of providing a single recording transducer. However, the method 250 may be used to fabricate multiple transducers substantially simultaneously. The method 250 and transducer 280 are also described in the context of a particular layer. The particular layer may include multiple materials and/or multiple sub-layers. Method 250 may be incorporated into methods 100 and 150 to provide a beveled pole. For example, the method 250 may be incorporated into step 112 and/or step 170-178.

A trench is formed in the intermediate layer, via step 252. The trench formed in step 252 is narrower near the ABS location where the ABS is located. Using step 252, the trench formed in step 110 and/or 170 of method 100 and/or 150 may have a profile that is narrower near the pole tip near the ABS location and wider near the yoke region of the pole. Step 252 may be performed by forming a portion of a hard mask adjacent the ABS region using a photoresist line, as described in methods 100 and 150. However, other portion(s) of the hard mask may have different profiles and be formed in another manner. Fig. 15 depicts a plan view of the transducer 280 after step 252 is completed. Fig. 16 depicts ABS location and yoke area views of the magnetic transducer 280 after step 252 is performed. Thus, the underlying layer 282 and the intermediate layer 284 are shown. The underlying layer 282 may be an etch stop layer. Trenches 286 are located between portions of the middle layer 284. As can be seen in fig. 15-16, the trench 286 can be viewed as including three regions, namely an ABS region adjacent the ABS location, an angle region, and a yoke region. The ABS position is marked by a line in FIG. 15 and shown in FIG. 16. The yoke view position is also labeled in fig. 15 and shown in fig. 16. The angular area is also indicated in fig. 15. As can be seen in FIGS. 15-16, the trench 286 is narrower in the track width direction near the ABS location than in the yoke region away from the ABS location.

As described above with respect to methods 100 and 150, additional nonmagnetic material(s) may be provided during formation of the magnetic poles. These materials may include additional insulating layers and/or seed layers. Therefore, these nonmagnetic materials are provided at a thickness sufficient to fill the bottom of the trench 286 close to the ABS, via step 254. Thus, in step 254, the deposition of nonmagnetic material in steps 112 and/or 172 continues until the material on the sidewalls of trench 286 grows together to fill the trench bottom to near the ABS location. However, in the yoke region, the bottom of trench 286 is not completely filled. In other words, the nonmagnetic material(s) at the bottom of the trench 286 are thicker proximate to the ABS location than distal from the ABS location.

Fig. 17-18 depict the magnetic transducer 280 after step 254 is completed and the magnetic material for the magnetic pole is deposited. Fig. 17 depicts ABS and yoke views of the magnetic transducer 280. Fig. 18 depicts a side view of the magnetic transducer 280. Thus, a non-magnetic material(s) 288 is provided. Although only a single layer is shown, the nonmagnetic material(s) 288 may comprise multiple layers. Thus, the bottom of trench 286 is filled in the ABS region, but not in the yoke region. Therefore, the nonmagnetic material(s) 288 are thicker in the ABS area, thinner along the angular areas, and thinnest in the yoke area. Thus, the depth of the trench 286 is smallest in the ABS region, increases along the angular region, and is deepest in the yoke region. For the magnetic recording transducer 280, the profile of the trench 286 changes diameter smoothly. However, in another embodiment, the diameter of the groove may be increased in another manner.

In step 256, the pole material(s) are provided and the desired planarization is performed. Fig. 19-20 depict the magnetic transducer 280 after step 256 is performed. Fig. 19 depicts ABS and yoke views of the magnetic transducer 280. Fig. 20 depicts a side view of the magnetic transducer 280. Thus, the pole material(s) 290 are provided. The thickness of the nonmagnetic material(s) 288 at the bottom of the trench 286 changes due to the change in the diameter of the trench 286. Thereby, the depth of the magnetic material 290 changes from the ABS position to the yoke region. The bottom bevel 292 may thus be formed.

A top bevel may optionally be provided, via step 258. In one embodiment, step 258 includes masking portions of the transducer 280 away from the ABS location and removing top portions of the pole material(s) 290. Fig. 21-22 depict the magnetic transducer 280 after step 258 is performed. Fig. 21 depicts ABS and yoke views of the magnetic transducer 280. Fig. 22 depicts a side view of the magnetic transducer 280. The pole 290' remains due to the removal of portions of the pole material(s). In addition to the ramp 292, a top ramp 294 is also formed.

Thus, in addition to the benefits achievable using methods 100 and 150, the chamfer(s) 292 and/or 294 may also be provided using method 250. The angled surface(s) 292 and 294 may improve magnetic flux concentration. Therefore, the high density performance of the magnetic transducer can be improved.

Claims (16)

1. A method of providing a perpendicular magnetic recording pole (PMR pole) in a magnetic recording transducer including an intermediate layer, the method comprising:

providing a mask on the intermediate layer, the mask comprising a line having at least one side;

providing a hard mask layer on the mask, a portion of the hard mask layer being on the at least one side edge;

removing at least a portion of the hard mask layer on the at least one side, at least a portion of the line being exposed;

removing the line, thereby providing an opening in the hard mask layer corresponding to the line;

forming a trench in the intermediate layer below the opening, the trench having a bottom and a top wider than the bottom; and

a PMR pole is provided, at least a portion of the PMR pole being located in the trench.

2. The method of claim 1, wherein the lines comprise photoresist lines.

3. The method of claim 2, wherein the step of removing the line further comprises:

stripping of the lines is performed.

4. The method of claim 1, wherein removing said at least a portion of said hardmask layer further comprises:

ion milling the magnetic recording transducer at an angle from a normal to a surface of the magnetic recording transducer.

5. The method of claim 4, wherein the angle is at least seventy degrees and no more than ninety degrees.

6. The method of claim 5, wherein the angle is at least seventy-seven degrees and no more than eighty-three degrees.

7. The method of claim 1, wherein the step of forming the trench further comprises:

at least one reactive ion etch, RIE, is performed to remove a portion of the intermediate layer.

8. The method of claim 7, further comprising:

a RIE etch stop is provided below the intermediate layer, a portion of the RIE etch stop forming the bottom of the trench.

9. The method of claim 1, further comprising:

providing a nonmagnetic layer, at least a portion of the nonmagnetic layer being located in the trench, the PMR magnetic pole being located on the nonmagnetic layer.

10. The method of claim 9, wherein the step of providing the nonmagnetic layer further comprises:

providing an aluminum oxide layer using atomic layer deposition; and

a seed layer is provided on the aluminum oxide layer.

11. The method of claim 9, wherein the magnetic recording transducer includes an Air Bearing Surface (ABS) region and a yoke region, and wherein the step of providing the trench further comprises:

providing the trench having a first width in the ABS area and a second width in the yoke area, the first width being less than the second width.

12. The method of claim 11, wherein the trench has a bottom, and wherein the step of providing the nonmagnetic layer further comprises:

the nonmagnetic layer is continuously deposited such that an ABS portion of the nonmagnetic layer on the bottom of the trench in the ABS area is thicker than a yoke portion of the nonmagnetic layer on the bottom of the trench in the yoke area.

13. The method of claim 1, further comprising:

providing a bottom anti-reflective coating (BARC) layer under the mask; and

transferring the line to the BARC prior to the step of providing the hard mask layer, a remaining portion of the BARC underlying the line.

14. The method of claim 13, further comprising:

after removing the line, removing the remaining portion of the BARC under the line.

15. The method of claim 1, wherein the top of the PMR pole has a width of no more than two hundred nanometers.

16. The method of claim 15, wherein the width is no more than one hundred nanometers.