DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 5/22/2025 has been entered.
Examiner’s Comment
The Examiner has cited particular columns and line numbers or figures in the references as applied to the claims below for the convenience of the applicant. Although the specified citations are representative of the teachings in the art and are applied to the specific limitations within the individual claim, other passages and figures may apply as well. It is respectfully requested from the applicant, in preparing the responses, to fully consider the references in entirety as potentially teaching all or part of the claimed invention, as well as the context of the passage as taught by the prior art or disclosed by the Examiner.
Regarding the limitation(s) “disposed outwardly” and “interfaces” in the claims, the Examiner has given the term(s) the broadest reasonable interpretation(s) consistent with the written description in Applicants’ specification as it would be interpreted by one of ordinary skill in the art. In re Morris, 127 F.3d 1048, 1054-55, 44 USPQ2d 1023, 1027 (Fed. Cir. 1997); In re Donaldson Co., Inc., 16 F.3d 1190, 1192-95, 29 USPQ2d 1845, 1848-50 (Fed. Cir. 1994). See MPEP 2111. For “disposed outwardly”, the Examiner notes that this refers to a layer order relative to a specific layer. However, due to the claimed read head being a three dimensional structure, a layer that is “disposed outwardly” may be below or above to said specific layer. For “interfaces”, the Examiner notes that this term still allows for other layers to be therebetween. Should Applicant desires to exclude other layers from being located therebetween, the Examiner suggests using the wording “directly in contact”.
Response to Amendment
Examiner acknowledges amended Claim 1 and canceled Claims 5, 9, and 12 in the response filed on 3/3/2025.
Response to Arguments
The declaration under 37 CFR 1.132 filed 5/22/2025 is insufficient to overcome the rejection of Claims 1-4, 6-8, 10, 11, 13-20 based upon the 35 USC § 103 rejections as set forth in the last Office action.
In the declaration, Applicant stated that for DFL read heads, it is a key requirement that soft bias shield shields (the lower stabilization layer 1004 and the upper stabilization layer 1006 in Jiang et al.) have anti-parallel magnetization direction. In order to make the lower and upper stabilization layers 1004, 1006 have anti-parallel magnetization directions, the lower stabilization layer 1004 is disposed in direct contact with the first lower magnetic shield layer 1506 or the first lower magnetic shield layer 1620, and the upper stabilization layer 1006 is disposed in direct contact with the first upper magnetic shield 1514 or the first upper magnetic shield 1606. The contact between the first lower magnetic shield layer 1620 and the lower stabilization layer 1004, and between the upper magnetic shield 1606 and the upper stabilization layer 1006, results in the first lower magnetic shield 1620 having a same magnetization direction as the lower stabilization layer 1004, and the first upper magnetic shield 1606 having a same configuration across the first lower magnetic shield layer 1620 and the first upper magnetic shield 1606 and the anti-parallel configuration between the lower and upper stabilization layers 1004, 1006 are coupled by this design.
However, Applicant’s statements are unpersuasive. Applicant amended Claim 1 by incorporating Claim 5, which recites “an insulation material between the first set of soft bias side shield layers and the magnetic seed layer”. While the Examiner acknowledges the magnetization directions of the lower stabilization layer 1004 and the first lower magnetic shield layer 1620 have the same magnetization direction, and upper stabilization layer 1006 and the first upper magnetic shield 1606 have the same magnetization direction, Applicant did not necessarily provide evidence or declare that incorporating an insulation layer, disclosed by Mao et al., would destroy Jiang et al.’s invention or negatively influence the magnetization directions of the respective layers (i.e. is it dependent on the insulation layer’s material, thickness, etc.?).
Applicant further stated that in their present application, the soft bias shield layers 335, 336 are separated by a non-magnetic layer 337, such as Ru (See paragraph [0039]). The thickness and material of the non-magnetic layer 337 is selected to make the soft bias shield layers 335, 336 anti-parallel coupled through RKKY interaction (See paragraph [0039]). Thus, the soft bias shield layers 335, 336 do not need to be in contact with the shield layer 318 or the magnetic seed layer 312.
The noted features above are recited in Claims 1, 3, and 4, which recites a set of nonmagnetic spacer layers between the first set of soft bias side shield layers and the second set of soft bias side shield layers, the nonmagnetic spacer material is ruthenium with a thickness of less than 10 Angstroms. Secondary reference, Mao et al., was used to teach the instant limitations. Applicant has not provided evidence or argued why it is not obvious to one of ordinary skill in the art to modify Jiang et al. in view of Mao et al. Applicant's arguments fail to comply with 37 CFR 1.111(b) because they amount to a general allegation that the claims define a patentable invention without specifically pointing out how the language of the claims patentably distinguishes them from the references.
Applicant argues that Xiao et al. discloses that the sensors 112 and 114 may employ a dual free layer scheme in which two free layers are biased in a scissor state (See paragraph [0018]). Xiao et al. does not disclose how the two free layers would be biased with only one bias layer (bias layer 111, for example).
However, Applicant’s arguments are unpersuasive. In response to Applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
While the Examiner acknowledges that Xiao et al. discloses the argued structure by Applicant, Xiao is not limited to such structure. Xiao teaches that other mechanisms for biasing the sensors 112 and 114 might also be used [0020]. Please note that Claims 11 and 13-17 do not recite structures to reduce sidebump imbalance by having soft bias side shield layers and nonmagnetic spacer layers.
As for Claims 18-20, Mao was relied upon to teach the soft bias side shield layers and nonmagnetic spacer layers in-between. Applicant has not provided evidence or argued why it is not obvious to one of ordinary skill in the art to modify Xiao et al. in view of Mao et al. Applicant's arguments fail to comply with 37 CFR 1.111(b) because they amount to a general allegation that the claims define a patentable invention without specifically pointing out how the language of the claims patentably distinguishes them from the references.
Applicant argues that Xiao et al. further discloses various anti-ferromagnetically coupled (AFC) shields 120’, 130, 160, 170 (See paragraph [0042]). The layers within AFC shields have anti-parallel magnetizations. However, Xiao et al. does not disclose that the bottom layer with a top shield (ferromagnetic layer 132, for example) and the top layer within a bottom shield (layer 121, for example) have to have anti-parallel magnetizations.
However, Applicant’s arguments are unpersuasive. While Xiao et al. Fig. 5 does not explicitly disclose/demonstrate the magnetization directions of the magnetic layers, the Examiner deems that it would have been obvious that these antiferromagnetically coupled layers in the respective shield structures reads on the claimed magnetization directions in order to provide thermal stability [0024], absence of evidence to the contrary. It is also noted that in each respective shield structures (120’, 130, 170, 160, 190’, and relevant thereof) may comprise a plurality of magnetic layers ([0023], [0026], [0027], [0038], and [0042]) (i.e. one of the magnetic layers in one shield structure will necessarily be antiparallel with one of the magnetic layer in another different shield structure).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-4, 7, 8, and 10 are rejected under 35 U.S.C. 103 as being unpatentable over US Pat. No. 9280992 (“Jiang et al.”) in view of US Pat. No. 11170809 (“Mao et al.”).
With regards to Claims 1, 3, and 4, Jiang et al. teaches a reader for magnetic recording devices comprising a lower magnetic shield (614), an upper magnetic shield (616), a first free layer (604) disposed between the lower and upper magnetic shields, a second free layer (606) disposed between the first free layer and the upper magnetic shield, a barrier layer (608) disposed between the first free layer and the second free layer, a cap layer (610) disposed in contact with the second free layer, a first set of soft bias side shield layers (1004) between the lower and upper magnetic shields, a second set of soft bias side shield layers (1006) between the first set of soft bias side shield layers and the upper magnetic shield (Fig. 10A, Col. 18: Line 10 bridging over to Col. 20: Line 47).
Jiang et al. teaches that its lower and upper magnetic shields ((614) and (616)) may have any of the disclosed laminated structures (e.g., Figs. 11-16) (Col. 19: Lines 12-15). Thus, Jiang et al. teaches its lower magnetic shield comprises a lower magnetic shield (1604) as demonstrated in Fig. 16, and its upper magnetic shield comprises an upper magnetic shield (1102) as demonstrated in Fig. 11.
Thus, Jiang et al. teaches a magnetic seed layer (1620) magnetized in a first direction, a shield layer (1104) magnetized in a second direction that is opposite of the first direction, a first free layer (604) disposed between the magnetic seed layer and the shield layer, a second free layer (606) disposed between the first free layer and the shield layer, a barrier layer (608) disposed between the first free layer and the second free layer, a first antiferromagnetic (AFM) layer (1636) disposed outwardly of the magnetic seed layer relative to the barrier layer, a second AFM layer (1106) disposed outwardly of the shield layer relative to the barrier layer, wherein the shield layer (1104) is disposed in contact with the second AFM (1106) and the cap layer (610) (Abstract, Figs. 10A, 11, and 16, Col. 7: Lines 61-62, Col. 9: Lines 49-63, and Col. 19: Line 51 bridging over to Col. 20: Line 12).
While Jiang et al. teaches a set of nonmagnetic spacer layers (622) between the first set of soft bias side shield layers and the second set of soft bias side shield layers (Fig. 10A), Jiang et al. does not teach the set of nonmagnetic spacer layers formed of a nonmagnetic spacer material that is electrically conductive ruthenium (Ru) and a thickness of each of the set of nonmagnetic spacer layers is less than 10 Angstroms. Jiang et al. does not teach an insulation material between the first set of soft bias side shield layers and the magnetic seed layer.
However, Mao et al. teaches a reader for magnetic recording devices comprising a first set of soft bias side shield layers (316a and 316b) between a magnetic seed layer and a shield layer, a second set of soft bias side shield layers (320a and 320b) between the first set of soft bias side shield layers and a shield layer, and a set of less than 10 Angstroms thick Ru nonmagnetic spacer layers (318a and 318b) between the first set of soft bias side shield layers and the second set of soft bias side shield layers (Fig. 3A, Col. 5: Lines 6-22, and Col. 6: Lines 31-59). Mao et al. teaches an insulation material (352) between its first set of soft bias side shield layers and its magnetic seed layer (Fig. 3A and Col. 7: Lines 12-23). It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have Jiang et al.’s first and second sets soft bias side shield layers be separated by a set of less than 10 Angstroms thick Ru nonmagnetic spacer layer to achieved an improved read head structure with higher areal density and head stability (Col. 1: Lines 56-58). It would also have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to incorporate an insulation material between Jiang et al.’s first set of soft bias side shield layers and its magnetic seed layer to avoid electrical shorting (Col. 7: Lines 12-16).
With regards to Claim 2, Jiang et al. teaches a nonmagnetic seed layer (612) disposed between the magnetic seed layer and the first free layer (Figs. 10A and 16; Col. 8: Lines 4-10).
With regards to Claim 7, Jiang et al. teaches the first AFM layer interfaces with the magnetic seed layer, and the second AFM layer interfaces with the shield layer (Figs. 11 and 16).
With regards to Claim 8, Jiang et al. teaches a second magnetic seed layer (1626) disposed between the magnetic seed layer and the first AFM layer, wherein the second magnetic seed layer is magnetized in the second direction, and a nonmagnetic spacer layer (1624) disposed between the magnetic seed layer and the second magnetic seed layer (Fig. 16 and Col. 19: Line 51 bridging over to Col. 20: Line 12).
With regards to Claim 10, Jiang et al. teaches a magnetic recording device comprising the reader (Figs. 1-5).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over US Pat. No. 9280992 (“Jiang et al.”) in view of US Pat. No. 11170809 (“Mao et al.”) as applied to Claim 1 above, and further in view of US Pub. No. 20140293474 (“Yamane et al.”).
Jiang et al. teaches the first and second AFM layers as set forth above.
Jiang et al. does not specifically teach the first AFM layer has a first blocking temperature and a second AFM layer has a second blocking temperature that is different than the first blocking temperature.
However, Yamane et al. teaches a reader wherein its first AFM layer (5) has a first blocking temperature and the second AFM layer (6) has a second blocking temperature that is different than the first blocking temperature (Fig. 4, [0028], and [0116]-[0119]). It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have Jiang et al.’s first and second AFM layers have different blocking temperatures in order to appropriately set and maintain magnetization directions of the shield structures ([0116]-[0119]).
Claims 11 and 13-17 are rejected under 35 U.S.C. 103 as being unpatentable over US Pub. No. 20160336030 (“Xiao et al.”).
With regards to Claim 11, Xiao et al. teaches a read head for magnetic recording devices comprising a lower reader comprising a lower magnetic seed layer (122, 126, and relevant thereof), a lower shield layer (132, 136, and relevant thereof), a first lower free layer (113) disposed between the lower magnetic seed layer and the lower shield layer, and second lower free layer (part of 112, see [0018]) disposed between the first lower free layer and the lower shield layer, a lower barrier layer (part of 112, see [0018]) disposed between the first lower free layer and the second lower free layer, a first antiferromagnetic (AFM) layer (128) disposed outwardly of the lower magnetic seed layer relative to the lower barrier layer, and a second AFM layer (138) disposed outwardly of the lower shield layer relative to the lower barrier layer.
Xiao et al. further teaches an upper reader comprising an upper magnetic seed layer (190’ or relevant thereof), an upper shield layer (162, 166, or relevant thereof), a first upper free layer (119) disposed between the upper magnetic seed layer and the upper shield layer, a second upper free layer (part of 118, see [0018] and [0038]) disposed between the first upper free layer and the upper shield layer, an upper barrier layer (part of 118, see [0018] and [0038]) disposed between the first upper free layer and the second upper free layer, and a fourth AFM (168) disposed outwardly of the upper shield layer relative to the upper barrier layer (Fig. 5, [0018], [0038], [0041], and [0042]).
Xiao et al. teaches a middle shield ((140) and (150)) comprising an insulating separation layer (140) in contact with the second AFM layer (138), and a shield (150) disposed in contact with the insulating separation layer (140) (Fig. 5, [0021]-[0023], and [0041]). Xiao et al. further teaches that its shield (150) may be AFC shields 120’, 130, 170 and 160 [0042]. Therefore, shield (150) may have the structure of shield (130), which comprises a shield layer (culmination of (132) to (136) – corresponding to Applicant’s middle shield layer) and an AFM layer ((138) – corresponding to Applicant’s third AFM). Therefore, Xiao et al. teaches a third AFM layer disposed between the upper magnetic seed layer and the second AFM layer and being disposed in contact with the middle shield layer ((132) to (136)).
Xiao et al. discloses that its shield structures (120’, 130, 170, 160, 190’, and relevant thereof) are each respectfully an antiferromagnetically coupled structure ([0023], [0024], [0026], [0033], [0038], [0041], and [0042]). That is, in each respective shield structures, a magnetic layer is magnetized in a first direction and another magnetic layer is magnetized in a second direction that is opposite of the first direction (i.e. antiparallel/antiferromagnetically coupled).
While Xiao et al. Fig. 5 does not explicitly disclose that the lower magnetic seed layer and upper shield layer having a first direction and the lower shield layer and upper magnetic seed layer have a second direction that is opposite of the first direction, the Examiner deems that it would have been obvious that these antiferromagnetically coupled layers in the respective shield structures, as described above, reads on the claimed magnetization directions in order to provide thermal stability [0024]. It is also noted that in each respective shield structures (120’, 130, 170, 160, 190’, and relevant thereof) may comprise a plurality of magnetic layers ([0023], [0026], [0027], [0038], and [0042]).
With regards to Claim 13, Xiao et al. teaches the lower reader further comprises a second lower magnetic seed layer (126) disposed between the lower magnetic seed layer (122) and the first AFM layer. Xiao et al. teaches a lower nonmagnetic spacer layer (124) disposed between the lower magnetic seed layer and the second lower magnetic seed layer. Xiao et al. teaches a second upper shield layer (166) disposed between the upper shield layer (162) and the fourth AFM layer, and an upper nonmagnetic spacer layer (164) disposed between the upper shield layer and the second upper shield layer (Fig. 5).
As noted above, Xiao et al. discloses that its shield structures (120’, 130, 170, 160, 190’, and relevant thereof) are each respectfully an antiferromagnetically coupled structure ([0023], [0024], [0026], [0033], [0038], [0041], and [0042]). That is, in each respective shield structures, a magnetic layer is magnetized in a first direction and another magnetic layer is magnetized in a second direction that is opposite of the first direction (i.e. antiparallel/antiferromagnetically coupled). Therefore, the Examiner deems that Xiao et al. teaches the second lower magnetic seed layer and second upper shield layer are magnetized in the second direction.
With regards to Claim 14, Xiao et al. teaches the first AFM layer interfaces with the second lower magnetic seed layer, the second AFM layer interfaces with the lower shield layer and the middle shield layer and the insulating separation layer, the third AFM layer interfaces with the upper magnetic seed layer, and the fourth AFM layer interfaces with the second upper shield layer (Fig. 5).
With regards to Claim 15, Xiao et al. teaches the lower reader further comprises a second lower shield layer (136) disposed between the lower shield layer (132) and the second AFM layer, a lower nonmagnetic spacer layer (134) disposed between the lower shield layer and the second lower shield layer.
Xiao et al. teaches a second upper magnetic seed layer (part of (190’) – please see [0032], [0038], and [0041]) disposed between the upper magnetic seed layer and the third AFM layer, and an upper nonmagnetic spacer layer (part of (190’) – please see [0032], [0038], and [0041]) disposed between the upper magnetic seed layer and the second upper magnetic seed layer (Fig. 5).
As noted above, Xiao et al. discloses that its shield structures (120’, 130, 170, 160, 190’, and relevant thereof) are each respectfully an antiferromagnetically coupled structure ([0023], [0024], [0026], [0033], [0038], [0041], and [0042]). That is, in each respective shield structures, a magnetic layer is magnetized in a first direction and another magnetic layer is magnetized in a second direction that is opposite of the first direction (i.e. antiparallel/antiferromagnetically coupled). Therefore, the Examiner deems that Xiao et al. teaches the second lower shield layer and second upper magnetic seed layer are magnetized in the first direction.
With regards to Claim 16, Xiao et al. teaches the first AFM layer interfaces with the lower magnetic seed layer, the second AFM layer interfaces with the second lower shield layer and the insulation separation layer, the third AFM layer interfaces with the second upper magnetic seed layer, and the fourth AFM layer interfaces with the upper shield layer (Fig. 5).
With regards to Claim 17, Xiao et al. teaches a magnetic recording device comprising the read head (Fig. 2A).
Claims 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over US Pub. No. 20160336030 (“Xiao et al.”) in view of US Pat. No. 11170809 (“Mao et al.”).
With regards to Claim 18, Xiao et al. teaches a read head for magnetic recording devices comprising a lower reader comprising a lower magnetic seed layer (122, 126, and relevant thereof), a lower shield layer (132, 136, and relevant thereof), a first lower free layer (113) disposed between the lower magnetic seed layer and the lower shield layer, a second lower free layer (part of 112, see [0018]) disposed between the first lower free layer and the lower shield layer, a first antiferromagnetic (AFM) layer (128) disposed outwardly of the lower magnetic seed layer, and a second AFM layer (138) disposed outwardly of the lower shield layer.
Xiao et al. further teaches an upper reader comprising an upper magnetic seed layer (190’ or relevant thereof), an upper shield layer (162, 166, or relevant thereof), a first upper free layer (119) disposed between the upper magnetic seed layer and the upper shield layer, a second upper free layer (part of 118, see [0018] and [0038]) disposed between the first upper free layer and the upper shield layer, and a fourth AFM (168) disposed outwardly of the upper shield layer (Fig. 5, [0018], [0038], [0041], and [0042]).
Xiao et al. teaches a middle shield ((140) and (150)) comprising an insulating separation layer (140) in contact with the second AFM layer (138), and a shield (150) disposed in contact with the insulating separation layer (140) (Fig. 5, [0021]-[0023], and [0041]). Xiao et al. further teaches that its shield (150) may be AFC shields 120’, 130, 170 and 160 [0042]. Therefore, shield (150) may have the structure of shield (130), which comprises a shield layer (culmination of (132) to (136) – corresponding to Applicant’s middle shield layer) and an AFM layer ((138) – corresponding to Applicant’s third AFM). Therefore, Xiao et al. teaches a third AFM layer (138) disposed between the upper magnetic seed layer and the second AFM layer and being disposed in contact with the middle shield layer ((132) to (136)).
Xiao et al. discloses that its shield structures (120’, 130, 170, 160, 190’, and relevant thereof) are each respectfully an antiferromagnetically coupled structure ([0023], [0024], [0026], [0033], [0038], [0041], and [0042]). That is, in each respective shield structures, a magnetic layer is magnetized in a first direction and another magnetic layer is magnetized in a second direction that is opposite of the first direction (i.e. antiparallel/antiferromagnetically coupled).
While Xiao et al. Fig. 5 does not explicitly disclose that the lower magnetic seed layer and upper shield layer having a first direction and the lower shield layer and upper magnetic seed layer have a second direction that is opposite of the first direction, the Examiner deems that it would have been obvious that these antiferromagnetically coupled layers in the respective shield structures, as described above, reads on the claimed magnetization directions in order to provide thermal stability [0024]. It is also noted that in each respective shield structures (120’, 130, 170, 160, 190’, and relevant thereof) may comprise a plurality of magnetic layers ([0023], [0026], [0027], [0038], and [0042]).
Xiao et al. teaches soft bias side shield layers (111) between the lower magnetic seed layer and the lower shield layer, and soft bias shield layers (117) between the upper magnetic seed layer and the upper shield layer (Fig. 5 and [0020]). Xiao et al. does not teach the claimed soft bias side shield layers structures as claimed. In Fig. 5 of Xiao et al., there appears to be an insulation material disposed between its free layers on a first side of the insulation material and soft bias side shield layers on a second side of the insulation material. However, Xiao et al.’s does not necessarily disclose as such in its written description.
However, Mao et al. teaches a reader for magnetic recording devices comprising a first set of soft bias side shield layers (316a and 316b), a second set of soft bias side shield layers (320a and 320b), and a set of less than 10 Angstroms thick Ru nonmagnetic spacer layers (318a and 318b) between the first set of soft bias side shield layers and the second set of soft bias side shield layers (Fig. 3A, Col. 5: Lines 6-22, and Col. 6: Lines 31-59). Mao et al. teaches that the first set and second set of soft bias side shield layers are antiferromagnetically coupled to each other (Col. 5: Lines 13-21 and Col. 6: Lines 31-32). Therefore, Mao et al. teaches the first set of soft bias side shield layers are magnetized in the first direction, and the second set of soft bias side shield layers are magnetized in the second direction. Mao et al. further teaches that an insulation material (352) is disposed between the free layers on a first side of the insulation material and the first and second sets of soft bias side shield layers on a second side of the insulation material (Fig. 3A and Col. 7: Lines 12-19).
It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have Xiao et al. soft bias side shield layers ((111) and (117)) have the claimed soft bias side shield layers structure in order to achieve an improved read head structure with higher areal density and head stability (Col. 1: Lines 56-58). It would also have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to incorporate an insulation material as claimed into Xiao et al.’s reader in order to avoid electrical shorting (Col. 7: Lines 12-19).
With regards to Claim 19, Xiao et al. teaches the lower and upper magnetic seed layers comprise one or more of nickel-iron (NiFe), cobalt-iron (CoFe), cobalt-boron (CoB), cobalt-iron-boron (CoFeB) ([0022], [0026], [0033], [0038], [0041], and [0042]). Xiao et al. further teaches its first, second, third, and fourth AFM layers comprise of IrMn [0025].
Xiao et al. does not teach the thickness of its nonmagnetic spacer layers, and the claimed conventional material(s) in its free layers.
However, Mao et al. teaches nonmagnetic spacer layers are less than 10 Angstroms (Col. 6: Lines 52-55). Mao et al. further teaches free layers comprise one or more of cobalt (Co), iron (Fe), and boron (B) (Col. 5: Lines 53-55 and Col. 6: Lines 5-6). It would have been obvious to one or ordinary skill in the art prior to the effective filing date of the claimed invention to have the nonmagnetic spacer layers be less than 10 Angstroms in order to be suitable in soft bias side shield structures. It would also have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have Xiao et al.’s free layers comprise one or more of cobalt (Co), iron (Fe), and boron (B) as they are recognized as suitable materials for free layers.
With regards to Claim 20, Xiao et al. teaches a magnetic recording device comprising the read head (Fig. 2A).
Claims 11 and 13-17 are rejected under 35 U.S.C. 103 as being unpatentable over US Pub. No. 20160336030 (“Xiao et al.”) in view of US Pat. No. 10777222 (“Liu et al.”).
With regards to Claim 11, Xiao et al. teaches a read head for magnetic recording devices comprising a lower reader comprising a lower magnetic seed layer (122, 126, and relevant thereof), a lower shield layer (132, 136, and relevant thereof), a first lower free layer (113) disposed between the lower magnetic seed layer and the lower shield layer, and second lower free layer (part of 112, see [0018]) disposed between the first lower free layer and the lower shield layer, a lower barrier layer (part of 112, see [0018]) disposed between the first lower free layer and the second lower free layer, a first antiferromagnetic (AFM) layer (128) disposed outwardly of the lower magnetic seed layer relative to the lower barrier layer, and a second AFM layer (138) disposed outwardly of the lower shield layer relative to the lower barrier layer.
Xiao et al. further teaches an upper reader comprising an upper magnetic seed layer (190’ or relevant thereof), an upper shield layer (162, 166, or relevant thereof), a first upper free layer (119) disposed between the upper magnetic seed layer and the upper shield layer, a second upper free layer (part of 118, see [0018] and [0038]) disposed between the first upper free layer and the upper shield layer, an upper barrier layer (part of 118, see [0018] and [0038]) disposed between the first upper free layer and the second upper free layer, and a fourth AFM (168) disposed outwardly of the upper shield layer relative to the upper barrier layer (Fig. 5, [0018], [0038], [0041], and [0042]).
Xiao et al. teaches a middle shield ((140) and (150)) comprising an insulating separation layer (140) in contact with the second AFM layer (138), and a shield (150) disposed in contact with the insulating separation layer (140) (Fig. 5, [0021]-[0023], and [0041]).
Xiao et al. discloses that its shield structures (120’, 130, 170, 160, 190’, and relevant thereof) are each respectfully an antiferromagnetically coupled structure ([0023], [0024], [0026], [0033], [0038], [0041], and [0042]). That is, in each respective shield structures, a magnetic layer is magnetized in a first direction and another magnetic layer is magnetized in a second direction that is opposite of the first direction (i.e. antiparallel/antiferromagnetically coupled).
While Xiao et al. Fig. 5 does not explicitly disclose that the lower magnetic seed layer and upper shield layer having a first direction and the lower shield layer and upper magnetic seed layer have a second direction that is opposite of the first direction, the Examiner deems that it would have been obvious that these antiferromagnetically coupled layers in the respective shield structures, as described above, reads on the claimed magnetization directions in order to provide thermal stability [0024]. It is also noted that in each respective shield structures (120’, 130, 170, 160, 190’, and relevant thereof) may comprise a plurality of magnetic layers ([0023], [0026], [0027], [0038], and [0042]).
While Xiao et al. teaches that its shield (150) may be AFC shields 120’, 130, 170 and 160 [0042], Xiao et al. does not necessarily disclose a singular middle shield layer in contact with the insulating separation layer and a third AFM layer.
However, Liu et al. teaches a read head comprising a middle shield, wherein the middle shield comprises an insulating separation layer (450) disposed in contact with a second AFM layer (362), and a singular middle shield layer (460) disposed in contact with the insulating separation layer. Liu et al. further teaches a third AFM layer (462) disposed in contact with the singular middle shield layer (Figs. 5 and Col. 6: Lines 14-67). It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have the claimed middle shield structure and third AFM layer in Xiao et al., as demonstrated by Liu et al., in order to produce a read head with favoring readback signal (Col. 1: Lines 9-12).
With regards to Claim 13, Xiao et al. teaches the lower reader further comprises a second lower magnetic seed layer (126) disposed between the lower magnetic seed layer (122) and the first AFM layer. Xiao et al. teaches a lower nonmagnetic spacer layer (124) disposed between the lower magnetic seed layer and the second lower magnetic seed layer. Xiao et al. teaches a second upper shield layer (166) disposed between the upper shield layer (162) and the fourth AFM layer, and an upper nonmagnetic spacer layer (164) disposed between the upper shield layer and the second upper shield layer (Fig. 5).
As noted above, Xiao et al. discloses that its shield structures (120’, 130, 170, 160, 190’, and relevant thereof) are each respectfully an antiferromagnetically coupled structure ([0023], [0024], [0026], [0033], [0038], [0041], and [0042]). That is, in each respective shield structures, a magnetic layer is magnetized in a first direction and another magnetic layer is magnetized in a second direction that is opposite of the first direction (i.e. antiparallel/antiferromagnetically coupled). Therefore, the Examiner deems that Xiao et al. teaches the second lower magnetic seed layer and second upper shield layer are magnetized in the second direction.
With regards to Claim 14, Xiao et al. teaches the first AFM layer interfaces with the second lower magnetic seed layer, the second AFM layer interfaces with the lower shield layer and the middle shield layer and the insulating separation layer, the third AFM layer interfaces with the upper magnetic seed layer, and the fourth AFM layer interfaces with the second upper shield layer (Fig. 5).
With regards to Claim 15, Xiao et al. teaches the lower reader further comprises a second lower shield layer (136) disposed between the lower shield layer (132) and the second AFM layer, a lower nonmagnetic spacer layer (134) disposed between the lower shield layer and the second lower shield layer.
Xiao et al. teaches a second upper magnetic seed layer (part of (190’) – please see [0032], [0038], and [0041]) disposed between the upper magnetic seed layer and the third AFM layer, and an upper nonmagnetic spacer layer (part of (190’) – please see [0032], [0038], and [0041]) disposed between the upper magnetic seed layer and the second upper magnetic seed layer (Fig. 5).
As noted above, Xiao et al. discloses that its shield structures (120’, 130, 170, 160, 190’, and relevant thereof) are each respectfully an antiferromagnetically coupled structure ([0023], [0024], [0026], [0033], [0038], [0041], and [0042]). That is, in each respective shield structures, a magnetic layer is magnetized in a first direction and another magnetic layer is magnetized in a second direction that is opposite of the first direction (i.e. antiparallel/antiferromagnetically coupled). Therefore, the Examiner deems that Xiao et al. teaches the second lower shield layer and second upper magnetic seed layer are magnetized in the first direction.
With regards to Claim 16, Xiao et al. teaches the first AFM layer interfaces with the lower magnetic seed layer, the second AFM layer interfaces with the second lower shield layer and the insulation separation layer, the third AFM layer interfaces with the second upper magnetic seed layer, and the fourth AFM layer interfaces with the upper shield layer (Fig. 5).
With regards to Claim 17, Xiao et al. teaches a magnetic recording device comprising the read head (Fig. 2A).
Claims 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over US Pub. No. 20160336030 (“Xiao et al.”), in view of US Pat. No. 10777222 (“Liu et al.”), and in view of US Pat. No. 11170809 (“Mao et al.”).
With regards to Claim 18, Xiao et al. teaches a read head for magnetic recording devices comprising a lower reader comprising a lower magnetic seed layer (122, 126, and relevant thereof), a lower shield layer (132, 136, and relevant thereof), a first lower free layer (113) disposed between the lower magnetic seed layer and the lower shield layer, a second lower free layer (part of 112, see [0018]) disposed between the first lower free layer and the lower shield layer, a first antiferromagnetic (AFM) layer (128) disposed outwardly of the lower magnetic seed layer, and a second AFM layer (138) disposed outwardly of the lower shield layer.
Xiao et al. teaches a middle shield ((140) and (150)) comprising an insulating separation layer (140) in contact with the second AFM layer (138), and a shield (150) disposed in contact with the insulating separation layer (140) (Fig. 5, [0021]-[0023], and [0041]).
Xiao et al. further teaches an upper reader comprising an upper magnetic seed layer (190’ or relevant thereof), an upper shield layer (162, 166, or relevant thereof), a first upper free layer (119) disposed between the upper magnetic seed layer and the upper shield layer, a second upper free layer (part of 118, see [0018] and [0038]) disposed between the first upper free layer and the upper shield layer, and a fourth AFM (168) disposed outwardly of the upper shield layer (Fig. 5, [0018], [0038], [0041], and [0042]).
Xiao et al. discloses that its shield structures (120’, 130, 170, 160, 190’, and relevant thereof) are each respectfully an antiferromagnetically coupled structure ([0023], [0024], [0026], [0033], [0038], [0041], and [0042]). That is, in each respective shield structures, a magnetic layer is magnetized in a first direction and another magnetic layer is magnetized in a second direction that is opposite of the first direction (i.e. antiparallel/antiferromagnetically coupled).
While Xiao et al. Fig. 5 does not explicitly disclose that the lower magnetic seed layer and upper shield layer having a first direction and the lower shield layer and upper magnetic seed layer have a second direction that is opposite of the first direction, the Examiner deems that it would have been obvious that these antiferromagnetically coupled layers in the respective shield structures, as described above, reads on the claimed magnetization directions in order to provide thermal stability [0024]. It is also noted that in each respective shield structures (120’, 130, 170, 160, 190’, and relevant thereof) may comprise a plurality of magnetic layers ([0023], [0026], [0027], [0038], and [0042]).
While Xiao et al. teaches that its shield (150) may be AFC shields 120’, 130, 170 and 160 [0042], Xiao et al. does not necessarily disclose a singular middle shield layer in contact with the insulating separation layer and a third AFM layer.
Xiao et al. teaches soft bias side shield layers (111) between the lower magnetic seed layer and the lower shield layer, and soft bias shield layers (117) between the upper magnetic seed layer and the upper shield layer (Fig. 5 and [0020]). Xiao et al. does not teach the claimed soft bias side shield layers structures as claimed. In Fig. 5 of Xiao et al., there appears to be an insulation material disposed between its free layers on a first side of the insulation material and soft bias side shield layers on a second side of the insulation material. However, Xiao et al.’s does not necessarily disclose as such in its written description.
Liu et al. teaches a read head comprising a middle shield, wherein the middle shield comprises an insulating separation layer (450) disposed in contact with a second AFM layer (362), and a singular middle shield layer (460) disposed in contact with the insulating separation layer. Liu et al. further teaches a third AFM layer (462) disposed in contact with the singular middle shield layer (Figs. 5 and Col. 6: Lines 14-67). It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have the claimed middle shield structure and third AFM layer in Xiao et al., as demonstrated by Liu et al., in order to produce a read head with favoring readback signal (Col. 1: Lines 9-12).
Mao et al. teaches a reader for magnetic recording devices comprising a first set of soft bias side shield layers (316a and 316b), a second set of soft bias side shield layers (320a and 320b), and a set of less than 10 Angstroms thick Ru nonmagnetic spacer layers (318a and 318b) between the first set of soft bias side shield layers and the second set of soft bias side shield layers (Fig. 3A, Col. 5: Lines 6-22, and Col. 6: Lines 31-59). Mao et al. teaches that the first set and second set of soft bias side shield layers are antiferromagnetically coupled to each other (Col. 5: Lines 13-21 and Col. 6: Lines 31-32). Therefore, Mao et al. teaches the first set of soft bias side shield layers are magnetized in the first direction, and the second set of soft bias side shield layers are magnetized in the second direction. Mao et al. further teaches that an insulation material (352) is disposed between the free layers on a first side of the insulation material and the first and second sets of soft bias side shield layers on a second side of the insulation material (Fig. 3A and Col. 7: Lines 12-19).
It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have Xiao et al. soft bias side shield layers ((111) and (117)) have the claimed soft bias side shield layers structure in order to achieve an improved read head structure with higher areal density and head stability (Col. 1: Lines 56-58). It would also have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to incorporate an insulation material as claimed into Xiao et al.’s reader in order to avoid electrical shorting (Col. 7: Lines 12-19).
With regards to Claim 19, Xiao et al. teaches the lower and upper magnetic seed layers comprise one or more of nickel-iron (NiFe), cobalt-iron (CoFe), cobalt-boron (CoB), cobalt-iron-boron (CoFeB) ([0022], [0026], [0033], [0038], [0041], and [0042]). Xiao et al. further teaches its first, second, third, and fourth AFM layers comprise of IrMn [0025].
Xiao et al. does not teach the thickness of its nonmagnetic spacer layers, and the claimed conventional material(s) in its free layers.
However, Mao et al. teaches nonmagnetic spacer layers are less than 10 Angstroms (Col. 6: Lines 52-55). Mao et al. further teaches free layers comprise one or more of cobalt (Co), iron (Fe), and boron (B) (Col. 5: Lines 53-55 and Col. 6: Lines 5-6). It would have been obvious to one or ordinary skill in the art prior to the effective filing date of the claimed invention to have the nonmagnetic spacer layers be less than 10 Angstroms in order to be suitable in soft bias side shield structures. It would also have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have Xiao et al.’s free layers comprise one or more of cobalt (Co), iron (Fe), and boron (B) as they are recognized as suitable materials for free layers.
With regards to Claim 20, Xiao et al. teaches a magnetic recording device comprising the read head (Fig. 2A).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US Pat No. 10586562 (“”Sapozhnikov et al.”) disclosed the claimed middle shield and third AFM layer (Figs. 3B and 5).
All claims are identical to or patentably indistinct from, or have unity of invention with claims in the application prior to the entry of the submission under 37 CFR 1.114 (that is, restriction (including a lack of unity of invention) would not be proper) and all claims could have been finally rejected on the grounds and art of record in the next Office action if they had been entered in the application prior to entry under 37 CFR 1.114. Accordingly, THIS ACTION IS MADE FINAL even though it is a first action after the filing of a request for continued examination and the submission under 37 CFR 1.114. See MPEP § 706.07(b). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to LISA CHAU whose telephone number is (571)270-5496. The examiner can normally be reached Monday-Friday 11 AM-730 PM.
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/LC/
Lisa Chau
Art Unit 1785
/Holly Rickman/Primary Examiner, Art Unit 1785