JP2002357489A - Stress sensor - Google Patents
Stress sensorInfo
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- JP2002357489A JP2002357489A JP2001164586A JP2001164586A JP2002357489A JP 2002357489 A JP2002357489 A JP 2002357489A JP 2001164586 A JP2001164586 A JP 2001164586A JP 2001164586 A JP2001164586 A JP 2001164586A JP 2002357489 A JP2002357489 A JP 2002357489A
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- magnetization
- stress
- free layer
- layer
- magnetic field
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- 230000005415 magnetization Effects 0.000 claims abstract description 333
- 239000010410 layer Substances 0.000 claims description 232
- 230000005291 magnetic effect Effects 0.000 claims description 95
- 238000009812 interlayer coupling reaction Methods 0.000 claims description 32
- 238000010030 laminating Methods 0.000 claims 1
- 230000000694 effects Effects 0.000 abstract description 67
- 238000009413 insulation Methods 0.000 abstract description 2
- 230000005290 antiferromagnetic effect Effects 0.000 description 11
- 230000015572 biosynthetic process Effects 0.000 description 8
- 239000010408 film Substances 0.000 description 8
- 230000007423 decrease Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 230000005330 Barkhausen effect Effects 0.000 description 3
- 230000003993 interaction Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 229910003321 CoFe Inorganic materials 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- 229910019041 PtMn Inorganic materials 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 230000002730 additional effect Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 230000005294 ferromagnetic effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000000059 patterning Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
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- Measuring Fluid Pressure (AREA)
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、歪みにより生じた
応力を電気信号に変換して出力する応力検知センサーに
関するものである。[0001] 1. Field of the Invention [0002] The present invention relates to a stress detection sensor that converts stress generated by strain into an electric signal and outputs the signal.
【０００２】[0002]
【従来の技術】従来から、応力検知センサーは、圧力セ
ンサー、および加速度センサー等に利用されており、応
力センサーとして、半導体センサー、および金属応力セ
ンサー等が利用されている。2. Description of the Related Art Conventionally, stress detection sensors have been used for pressure sensors, acceleration sensors, and the like, and semiconductor sensors, metal stress sensors, and the like have been used as stress sensors.
【０００３】この応力センサーの一つとして、特開平７
−２０９１００号公報のように、磁気抵抗効果を用いた
応力センサーが提案されている。One of such stress sensors is disclosed in
As in Japanese Patent Application Laid-Open No. 209100, a stress sensor using a magnetoresistance effect has been proposed.
【０００４】この応力センサーは図１３に示すように、
強磁性薄膜からなる略正方形形状をした磁気抵抗効果素
子１３１に、対角線方向に一軸異方性を設定し、電流に
対し、ほぼ４５゜の角度に磁化することにより、歪みの
加わる方向が正方向に加えられたときと、負方向に加え
られたときとで異なる抵抗値を発生する。[0004] As shown in FIG.
Uniaxial anisotropy is set in the diagonal direction on the magnetoresistive element 131 having a substantially square shape made of a ferromagnetic thin film, and the current is magnetized at an angle of approximately 45 ° so that the direction in which the strain is applied is positive. And a different resistance value when applied in the negative direction.
【０００５】[0005]
【発明が解決しようとする課題】ところで、この従来の
磁気抵抗効果素子では異方性磁気抵抗効果を用いている
ため、抵抗変化量が３％程度と小さく、小さな歪み量で
は出力が小さく、また、歪み量が大きくなると出力の線
形性が悪くなるという問題点を有していた。However, since the conventional magnetoresistive element uses the anisotropic magnetoresistive effect, the resistance change is as small as about 3%, and the output is small with a small amount of distortion. In addition, there is a problem that the output linearity deteriorates when the amount of distortion increases.
【０００６】本発明はこのような課題を解決するために
なされたもので、出力が大きく、出力の線形性の大きい
応力センサーを提供することを目的とする。SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and has as its object to provide a stress sensor having a large output and a large output linearity.
【０００７】[0007]
【課題を解決するための手段】この目的を達成するた
め、本発明の請求項１に記載の応力センサーは、磁化が
一方向に固着されている磁化固着層と、絶縁層と、磁歪
を有する磁化自由層とを順次積層してなる磁気抵抗効果
素子を備えた応力センサーであって、前記磁気抵抗効果
素子に応力が印加されたときに、前記磁気抵抗効果素子
の抵抗値変化から、印加された応力を検知する。磁気抵
抗効果素子は、いわゆるＴＭＲ（トンネル磁気抵抗効
果）素子を構成するため、ＭＲ比が大きく、出力が高い
応力センサーを得ることができる。In order to achieve this object, a stress sensor according to a first aspect of the present invention has a magnetization fixed layer in which magnetization is fixed in one direction, an insulating layer, and magnetostriction. A stress sensor including a magnetoresistive element in which a magnetization free layer is sequentially stacked, wherein when a stress is applied to the magnetoresistive element, the stress is applied based on a change in the resistance value of the magnetoresistive element. Detected stress. Since the magnetoresistive element constitutes a so-called TMR (tunnel magnetoresistive effect) element, a stress sensor having a large MR ratio and a high output can be obtained.
【０００８】本発明の請求項２に記載の発明は、請求項
１に記載の応力センサーにおいて、前記磁気抵抗効果素
子を円形状にパターニングしたものである。この構成に
より、磁気抵抗効果素子に、応力が印加されたとき、逆
磁歪効果により発生した異方性エネルギーにより、磁化
自由層の磁化が回転する際、形状が円形であるため、反
磁界係数は、磁化がどの方向であっても同じであるの
で、形状異方性による影響を受けることなく、抵抗変化
の線形性を向上させるという作用を有する。これによ
り、高出力で線形成の良い応力センサーを得ることがで
きる。According to a second aspect of the present invention, in the stress sensor according to the first aspect, the magnetoresistance effect element is patterned in a circular shape. With this configuration, when a stress is applied to the magnetoresistive effect element, the anisotropic energy generated by the inverse magnetostriction effect causes the magnetization of the magnetization free layer to rotate. Since the magnetization is the same in any direction, it has the effect of improving the linearity of the resistance change without being affected by the shape anisotropy. As a result, a high-output stress sensor with good line formation can be obtained.
【０００９】本発明の請求項３に記載の発明は、請求項
１、あるいは請求項２のいずれかに記載の応力センサー
において、前記磁気抵抗効果素子は、前記磁化自由層上
に、さらに導体層と磁化固着層とを順次積層してなるも
のとしたものである。この構成により、ＭＲ比を１５％
程度にすることも可能で、応力に対する抵抗変化率をさ
らに上げることができる。これにより、高出力で線形成
の良い応力センサーを得ることができる。According to a third aspect of the present invention, in the stress sensor according to any one of the first and second aspects, the magnetoresistive effect element further comprises a conductor layer on the magnetization free layer. And the magnetization fixed layer are sequentially laminated. With this configuration, the MR ratio is increased by 15%.
The resistance change rate with respect to stress can be further increased. As a result, a high-output stress sensor with good line formation can be obtained.
【００１０】本発明の請求項４に記載の発明は、請求項
１ないし請求項３のいずれかに記載の応力センサーにお
いて、応力が印加されることにより、前記磁化固着層と
前記磁化自由層との間に、層間結合磁界が発生した場
合、前記磁化固着層の磁化方向と、前記磁化自由層の磁
化容易軸方向とを略直交させ、前記層間結合磁界を打ち
消すように、バイアス磁界を印加するものである。無応
力時において、磁化固着層の磁化と、磁化自由層の磁化
を略直交させることができ、磁気抵抗効果素子の抵抗変
化の線形性を向上させるという作用を有する。これによ
り、高出力で線形成の良い応力センサーを得ることがで
きる。According to a fourth aspect of the present invention, in the stress sensor according to any one of the first to third aspects, when a stress is applied, the magnetization fixed layer and the magnetization free layer are separated from each other. When an interlayer coupling magnetic field is generated during this time, a bias magnetic field is applied so that the magnetization direction of the magnetization fixed layer and the easy axis direction of the magnetization free layer are substantially orthogonal to each other and the interlayer coupling magnetic field is canceled. Things. At the time of no stress, the magnetization of the magnetization fixed layer and the magnetization of the magnetization free layer can be made substantially orthogonal to each other, and has an effect of improving the linearity of the resistance change of the magnetoresistive element. As a result, a high-output stress sensor with good line formation can be obtained.
【００１１】本発明の請求項５に記載の発明は、請求項
１ないし請求項３のいずれかに記載の応力センサーにお
いて、磁化自由層に対し、磁化容易軸方向にバイアス磁
界を印加するとともに、前記磁化自由層の磁化容易軸と
前記磁化固着層の磁化方向との角度αと、前記バイアス
磁界とが、Ｈk×cosα×sinα＋Ｈbias×cosα＋Ｈint
＝０、かつ−Hk×cos(2α)＋Hbias×sinα＞０（Ｈk：
磁化自由層の異方性磁界、Ｈint：磁化固着層と磁化自
由層との層間結合磁界、Ｈbias：磁化自由層に対し、磁
化容易軸方向に印加するバイアス磁界）を略満たすもの
としたものである。この構成により、磁気抵抗素子が層
間結合磁界Ｈintを有する場合においても、応力印加が
ない状態の時の磁化自由層の磁化方向と、磁化固着層の
磁化方向を直交させることができるため、応力の印加に
応じて、磁気抵抗効果素子の抵抗値の変化量を大きくす
るという作用を有する。これにより、高出力で線形成の
良い応力センサーを得ることができる。According to a fifth aspect of the present invention, in the stress sensor according to any one of the first to third aspects, a bias magnetic field is applied to the magnetization free layer in the direction of the easy axis of magnetization. The angle α between the easy axis of the magnetization free layer and the magnetization direction of the magnetization pinned layer and the bias magnetic field are Hk × cosα × sinα + Hbias × cosα + Hint
= 0 and −Hk × cos (2α) + Hbias × sinα> 0 (Hk:
An anisotropic magnetic field of the magnetization free layer, Hint: an interlayer coupling magnetic field between the magnetization fixed layer and the magnetization free layer, and Hbias: a bias magnetic field applied to the magnetization free layer in the easy axis direction. is there. With this configuration, even when the magnetoresistive element has the interlayer coupling magnetic field Hint, the magnetization direction of the magnetization free layer when no stress is applied and the magnetization direction of the magnetization fixed layer can be made orthogonal to each other. This has the effect of increasing the amount of change in the resistance value of the magnetoresistive element according to the application. As a result, a high-output stress sensor with good line formation can be obtained.
【００１２】本発明の請求項６に記載の発明は、請求項
１ないし請求項５のいずれかに記載の応力センサーにお
いて、前記応力の印加方向が、前記磁化固着層の磁化方
向に対し＋４５゜あるいは−４５゜のいずれかであるも
のとしたものである。この構成により、磁気抵抗効果素
子の抵抗変化は応力の正負に対して線形性が向上すると
いう作用を有する。これにより、高出力で線形成の良い
応力センサーを得ることができる。According to a sixth aspect of the present invention, in the stress sensor according to any one of the first to fifth aspects, the direction in which the stress is applied is + 45 ° with respect to the magnetization direction of the magnetization fixed layer. Or -45 °. With this configuration, the resistance change of the magnetoresistive element has an effect that linearity is improved with respect to the positive or negative of the stress. As a result, a high-output stress sensor with good line formation can be obtained.
【００１３】本発明の請求項７に記載の発明は、請求項
１ないし請求項５のいずれかに記載の応力センサーにお
いて、前記応力の印加方向が、無応力時の磁化自由層の
磁化方向に対し、＋４５゜あるいは−４５゜のいずれか
であるものとしたものである。この構成により、磁気抵
抗効果素子の出力を増加させると共に、出力の線形性を
向上させるという作用を有する。これにより、高出力で
線形成の良い応力センサーを得ることができる。According to a seventh aspect of the present invention, in the stress sensor according to any one of the first to fifth aspects, the direction in which the stress is applied is the same as the direction of magnetization of the magnetization free layer when there is no stress. On the other hand, the angle is either + 45 ° or −45 °. With this configuration, the output of the magnetoresistive effect element is increased, and the linearity of the output is improved. As a result, a high-output stress sensor with good line formation can be obtained.
【００１４】[0014]
【発明の実施の形態】以下、本発明の実施の形態につい
て図面を用いて説明する。 （実施の形態１）図１は本発明の実施の形態１における
応力センサーの斜視図である。図１に示すように、磁気
抵抗効果素子１は電極１１ａ上に反強磁性層１０、磁化
固着層２、絶縁層３、および磁化自由層４が順次積層さ
れ、その上に電極１１ｂが積層されている。電極１１
ａ、および１１ｂにより、磁気抵抗効果素子１の膜厚方
向にセンス電流が印加される。Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 FIG. 1 is a perspective view of a stress sensor according to Embodiment 1 of the present invention. As shown in FIG. 1, in the magnetoresistive element 1, an antiferromagnetic layer 10, a magnetization fixed layer 2, an insulating layer 3, and a magnetization free layer 4 are sequentially stacked on an electrode 11a, and an electrode 11b is stacked thereon. ing. Electrode 11
By means of a and 11b, a sense current is applied in the thickness direction of the magnetoresistive effect element 1.
【００１５】図２に磁化固着層３、絶縁層４、および磁
化自由層５を記載し、磁化状態について説明する。FIG. 2 illustrates the magnetization fixed layer 3, the insulating layer 4, and the magnetization free layer 5, and the magnetization state will be described.
【００１６】磁化固着層２の磁化Ｍpin５は一方向に固
着されている。これは、反強磁性層１０により、磁化固
着層２の磁化Ｍpin５が一方向に固着するためである。
本実施の形態では反強磁性層を用いたが、硬質磁性層を
用いてもよい。The magnetization Mpin 5 of the magnetization fixed layer 2 is fixed in one direction. This is because the magnetization Mpin 5 of the magnetization fixed layer 2 is fixed in one direction by the antiferromagnetic layer 10.
In the present embodiment, the antiferromagnetic layer is used, but a hard magnetic layer may be used.
【００１７】磁化自由層４は、一軸異方性を有し、磁化
容易軸方向６を磁気抵抗効果素子１の長手方向に設定し
ている。磁化自由層４の磁化Ｍfree７は応力無印加時に
は容易軸方向６に平行である。磁化自由層４の磁歪定数
λは正である。なお、磁化固着層２の磁化Ｍpin５と磁
化自由層４の磁化容易軸６とは略直交しており、磁化Ｍ
free７は無応力時には磁化容易軸方向を向くため、磁化
Ｍpin５と磁化Ｍfree７との角度は、応力無印加時には
略直交している。The magnetization free layer 4 has uniaxial anisotropy, and the easy axis direction 6 is set in the longitudinal direction of the magnetoresistive element 1. The magnetization Mfree7 of the magnetization free layer 4 is parallel to the easy axis direction 6 when no stress is applied. The magnetostriction constant λ of the magnetization free layer 4 is positive. Note that the magnetization Mpin 5 of the magnetization fixed layer 2 and the easy axis 6 of the magnetization free layer 4 are substantially orthogonal to each other.
Since free7 is oriented in the direction of the axis of easy magnetization when no stress is applied, the angle between the magnetization Mpin5 and the magnetization Mfree7 is substantially orthogonal when no stress is applied.
【００１８】磁化固着層２の磁化を固着するための反強
磁性膜はPtMnで形成し、磁化固着層２はCoFeで形成し、
絶縁層３はAlを自然酸化したAl2O3で形成し、磁化自由
層４はCoFeで形成した。The antiferromagnetic film for fixing the magnetization of the magnetization fixed layer 2 is formed of PtMn, and the magnetization fixed layer 2 is formed of CoFe.
The insulating layer 3 was formed of Al 2 O 3 obtained by naturally oxidizing Al, and the magnetization free layer 4 was formed of CoFe.
【００１９】磁気抵抗効果素子１における磁化固着層２
の磁化方向と磁化自由層４の磁化容易軸とを設定するた
め、まず、磁化固着層２の磁化を固着させたい方向に磁
場を印加しながら３００゜Ｃ程度の熱処理を所定の時間
行い、続いて温度２５０゜Ｃ程度に下げると共に、印加
磁場を、設定する磁化自由層４の磁化容易軸方向に向け
所定の時間、熱処理を行う。Fixed magnetization layer 2 in magnetoresistance effect element 1
First, a heat treatment of about 300 ° C. is performed for a predetermined time while applying a magnetic field in a direction in which the magnetization of the magnetization fixed layer 2 is to be fixed, in order to set the magnetization direction of the magnetization free layer 4 and the easy axis of magnetization. The temperature is lowered to about 250 ° C., and the applied magnetic field is heat-treated for a predetermined time in the direction of the easy axis of magnetization of the magnetization free layer 4 to be set.
【００２０】磁気抵抗効果素子１の抵抗値は、磁化固着
層２の磁化Ｍpin５と磁化自由層４の磁化Ｍfree７の角
度に依存し、角度が０°（平行）の時、抵抗値は最小と
なり、角度が１８０゜（反平行）の時、最大となる。The resistance value of the magnetoresistive element 1 depends on the angle between the magnetization Mpin 5 of the magnetization pinned layer 2 and the magnetization Mfree 7 of the magnetization free layer 4, and when the angle is 0 ° (parallel), the resistance value becomes minimum, When the angle is 180 ° (anti-parallel), it becomes maximum.
【００２１】図２中、矢印８、および９は応力の印加方
向であり、互いに直交しており、本実施の形態では矢印
８と磁化固着層Ｍpinとの角度は４５゜とした。In FIG. 2, arrows 8 and 9 indicate the directions in which the stress is applied, and are perpendicular to each other. In this embodiment, the angle between the arrow 8 and the magnetization fixed layer Mpin is 45 °.
【００２２】次に、応力印加時の動作について説明す
る。Next, the operation at the time of applying a stress will be described.
【００２３】磁気抵抗効果素子１には電極１１ａ、およ
び１１ｂにより、磁気抵抗効果素子１の膜厚方向にセン
ス電流が印加されている。A sense current is applied to the magnetoresistive element 1 in the thickness direction of the magnetoresistive element 1 by the electrodes 11a and 11b.
【００２４】磁気抵抗効果素子１に矢印８の方向に引っ
張り応力σ（＞０）が印加されると、磁歪の逆効果によ
り、応力印加方向８の方向に異方性エネルギーＥσ（＝
３λσ／２＞０）が生じるため、磁化自由層４の磁化Ｍ
free７は、応力印加方向８の方向へ回転する（図２
（ｂ））。従って、磁化自由層の磁化Ｍfree７と磁化固
着層５の磁化Ｍpin５との角度が９０゜より小さくなる
ため、磁気抵抗効果素子１の抵抗値が減少する。When a tensile stress σ (> 0) is applied to the magnetoresistive element 1 in the direction of arrow 8, the anisotropic energy Eσ (=
3λσ / 2> 0), the magnetization M of the magnetization free layer 4
free7 rotates in the direction of the stress application direction 8 (see FIG. 2).
(B)). Accordingly, since the angle between the magnetization Mfree7 of the magnetization free layer and the magnetization Mpin5 of the magnetization fixed layer 5 becomes smaller than 90 °, the resistance value of the magnetoresistive element 1 decreases.
【００２５】磁気抵抗効果素子１に矢印８の方向に圧縮
応力σ（＜０）が印加されると、上記の場合と同様に磁
歪の逆効果により、異方性エネルギーＥσ（＝−３λσ
／２＜０）が生じるが、このときは、矢印９の方向に異
方性が生じることとなり、磁化自由層４の磁化Ｍfree７
は、矢印９の方向へ回転する（図２（ｃ））。従って、
磁化自由層４の磁化Ｍfree７と磁化固着層５との角度が
９０゜より大きくなるため、磁気抵抗効果素子１の抵抗
値が増加する。When a compressive stress σ (<0) is applied to the magnetoresistive element 1 in the direction of arrow 8, the anisotropic energy Eσ (= −3λσ) is obtained due to the adverse effect of magnetostriction as in the above case.
/ 2 <0), but in this case, anisotropy occurs in the direction of arrow 9 and magnetization Mfree7 of magnetization free layer 4 is generated.
Rotates in the direction of arrow 9 (FIG. 2C). Therefore,
Since the angle between the magnetization Mfree 7 of the magnetization free layer 4 and the magnetization fixed layer 5 is larger than 90 °, the resistance value of the magnetoresistive element 1 increases.
【００２６】また、引っ張り応力σが矢印９の方向に印
加されたときは、矢印９の方向に異方性が発生し、磁化
自由層の磁化Ｍfree７は、矢印９の方向へ回転（図２
（ｃ））し、磁気抵抗効果素子１の抵抗値が増加し、圧
縮応力σが矢印９の方向に印加されたときは、矢印８の
方向に異方性が発生し、磁化自由層の磁化Ｍfree７は、
矢印８の方向へ回転（図２（ｂ））し、磁気抵抗効果素
子１の抵抗値が減少する。When a tensile stress σ is applied in the direction of arrow 9, anisotropy occurs in the direction of arrow 9, and the magnetization Mfree7 of the magnetization free layer rotates in the direction of arrow 9 (FIG. 2).
(C)) Then, when the resistance value of the magnetoresistive element 1 increases and a compressive stress σ is applied in the direction of arrow 9, anisotropy occurs in the direction of arrow 8 and the magnetization of the magnetization free layer Mfree7 is
Rotation in the direction of arrow 8 (FIG. 2B) causes the resistance of the magnetoresistive element 1 to decrease.
【００２７】このように、印加する応力の方向を矢印８
または９の方向いずれかの方向に設定することにより、
応力が引っ張り応力であるか、圧縮応力であるかに応じ
て、抵抗値が変化する。Thus, the direction of the applied stress is indicated by the arrow 8.
Or by setting one of the 9 directions,
The resistance value changes depending on whether the stress is a tensile stress or a compressive stress.
【００２８】矢印８は磁化固着層５の磁化Ｍpin５に対
し、略４５゜の角度を有しており、矢印９は矢印８に対
して直交している。The arrow 8 has an angle of about 45 ° with respect to the magnetization Mpin 5 of the magnetization fixed layer 5, and the arrow 9 is orthogonal to the arrow 8.
【００２９】磁気抵抗効果素子１の磁気抵抗変化率（Ｍ
Ｒ比）が１５％、磁歪定数λが5×10-6の場合の応力に
対する抵抗変化率を図３に示す。応力は矢印９方向に印
加した。図３に、従来の磁気抵抗効果素子（磁気抵抗変
化率３％）を用いたときの抵抗変化率を示す。従来の磁
気抵抗効果素子の磁歪定数は5×10-6とした。The rate of change in magnetoresistance of the magnetoresistance effect element 1 (M
FIG. 3 shows the rate of change in resistance with respect to stress when the R ratio is 15% and the magnetostriction constant λ is 5 × 10 −6 . Stress was applied in the direction of arrow 9. FIG. 3 shows a resistance change rate when a conventional magnetoresistance effect element (a magnetoresistance change rate of 3%) is used. The magnetostriction constant of the conventional magnetoresistance effect element was set to 5 × 10 −6 .
【００３０】図３に示すように、本実施の形態の磁気抵
抗効果素子１では、ＭＲ比が大きいため、応力による抵
抗変化率も大きくなっていることがわかる。本実施の形
態の磁気抵抗効果素子では、絶縁層３の膜厚や磁化自由
層４の膜厚、および材料等を最適化することにより、Ｍ
Ｒ比をさらに増大することができる。As shown in FIG. 3, in the magnetoresistive element 1 of the present embodiment, the MR ratio is large, so that the rate of change in resistance due to stress is also large. In the magnetoresistive effect element according to the present embodiment, by optimizing the thickness of the insulating layer 3, the thickness of the magnetization free layer 4, the material, and the like, the M
The R ratio can be further increased.
【００３１】また、磁化自由層６の上に絶縁層、および
磁化固着層をさらに積層するいわゆるデュアル構造とす
ることにより、ＭＲ比を１５％程度にすることも可能
で、応力に対する抵抗変化率をさらに上げることができ
る。By forming a so-called dual structure in which an insulating layer and a magnetization fixed layer are further laminated on the magnetization free layer 6, the MR ratio can be made about 15%, and the resistance change rate with respect to stress can be reduced. Can be raised further.
【００３２】また、従来の磁気抵抗効果素子のシート抵
抗は７Ω程度と小さく、小さい応力を検知する際、抵抗
変化量も小さいため、読みとり誤差が発生する。従来の
磁気抵抗効果素子の抵抗値を大きくするためには、磁気
抵抗効果素子のパターン形状をセンス電流の流れる方向
に長くすることが必要となるが、そうなると、磁気抵抗
効果素子の形状が大きくなり、応力センサーの小型化が
困難となる。Further, the sheet resistance of the conventional magnetoresistance effect element is as small as about 7Ω, and when detecting a small stress, a reading error occurs due to a small resistance change amount. In order to increase the resistance value of the conventional magnetoresistive element, it is necessary to lengthen the pattern shape of the magnetoresistive element in the direction in which the sense current flows, but in such a case, the shape of the magnetoresistive element becomes large. This makes it difficult to reduce the size of the stress sensor.
【００３３】一方、本発明の磁気抵抗効果素子によれ
ば、抵抗値は５０Ω／μｍ2程度であるが、本発明の磁
気抵抗効果素子は、電流を膜厚方向に印加するため、電
流の流れる断面積がパターン形状となり、磁気抵抗効果
素子の形状を小さくすれば、抵抗値は増大するため、微
小な領域の微小な応力を検知できるというさらなる効果
を有する。On the other hand, according to the magnetoresistive element of the present invention, the resistance is about 50 Ω / μm 2 , but the magnetoresistive element of the present invention applies a current in the film thickness direction, so that the current flows. If the cross-sectional area becomes a pattern shape and the shape of the magnetoresistive element is reduced, the resistance value increases, so that there is an additional effect that a minute stress in a minute region can be detected.
【００３４】また、絶縁層の厚さを厚くすればさらに抵
抗値を増大させることができるばかりでなく、磁気抵抗
効果素子の形成を容易にするという利点もある。これ
は、本発明の磁気抵抗効果素子がトンネル効果を利用す
るためであり、絶縁層が薄い場合、下地の粗さ等の影響
を受け、良好なトンネル効果が得られない場合があるた
めであり、また、磁気抵抗効果素子をパターニングする
際、絶縁層が薄いと、絶縁層の上下の磁化固着層や磁化
自由層が、エッチング残り等の影響で電気的に短絡し、
トンネル効果を劣化させることになるためである。絶縁
層を厚くできれば、上記の劣化要因をさけることができ
るため、磁気抵抗効果素子の形成が容易になるというこ
とである。When the thickness of the insulating layer is increased, not only the resistance can be further increased, but also there is an advantage that the formation of the magnetoresistive element is facilitated. This is because the magnetoresistance effect element of the present invention utilizes the tunnel effect, and when the insulating layer is thin, the tunnel effect may not be obtained due to the influence of the roughness of the base and the like. Also, when patterning the magnetoresistive element, if the insulating layer is thin, the magnetization fixed layer and the magnetization free layer above and below the insulating layer are electrically short-circuited due to the influence of the remaining etching, etc.
This is because the tunnel effect is deteriorated. If the thickness of the insulating layer can be increased, the above-mentioned deterioration factors can be avoided, and thus the formation of the magnetoresistive element can be facilitated.
【００３５】なお、本実施の形態では磁気抵抗素子１の
磁歪定数を正としたが、負の場合であっても、応力印加
方向、および生ずる異方性エネルギーＥσの正負によ
り、生じた異方性の方向が決定され、上記の場合と抵抗
変化において変わることはない。 （実施の形態２）図４に本発明の実施の形態２における
応力センサーの斜視図を示す。磁気抵抗効果素子４１は
電極５２ａ上に、反強磁性膜５１、磁化固着層４２、絶
縁層４３、および磁化自由層４４が順次積層され、その
上に電極５２ｂが積層されている。電極５１ａ、および
５２ｂにより、センス電流が磁気抵抗効果素子４１の膜
厚方向に印加される。In this embodiment, the magnetostriction constant of the magnetoresistive element 1 is positive. However, even if the magnetoresistance element 1 is negative, the anisotropy generated due to the stress application direction and the sign of the generated anisotropic energy Eσ. The direction of sex is determined and does not change in the resistance change from the above case. (Embodiment 2) FIG. 4 is a perspective view of a stress sensor according to Embodiment 2 of the present invention. In the magnetoresistive element 41, an antiferromagnetic film 51, a magnetization fixed layer 42, an insulating layer 43, and a magnetization free layer 44 are sequentially stacked on an electrode 52a, and an electrode 52b is stacked thereon. A sense current is applied in the thickness direction of the magnetoresistive element 41 by the electrodes 51a and 52b.
【００３６】磁気抵抗効果素子４１は円形にパターニン
グされている。The magneto-resistance effect element 41 is circularly patterned.
【００３７】磁気抵抗効果素子４１の磁化状態を図５を
用いて説明する。The magnetization state of the magnetoresistive element 41 will be described with reference to FIG.
【００３８】反強磁性層５１は磁化固着層４２の磁化Ｍ
pin４５は一方向に固着する。The antiferromagnetic layer 51 has a magnetization M
The pin 45 is fixed in one direction.
【００３９】磁化自由層４４は、磁化容易軸方向４６の
方向に一軸異方性を有している。磁化自由層４４の磁化
Ｍfree４７は応力無印加時には容易軸方向４６に平行で
ある。磁化自由層４４の磁歪定数λは正である。なお、
磁化固着層４２の磁化Ｍpin４５と磁化自由層４４の磁
化Ｍfree４７との角度は、応力無印加時には略直交して
いることは実施の形態１と同様である。The magnetization free layer 44 has uniaxial anisotropy in the direction of the easy axis 46. The magnetization Mfree 47 of the magnetization free layer 44 is parallel to the easy axis direction 46 when no stress is applied. The magnetostriction constant λ of the magnetization free layer 44 is positive. In addition,
As in the first embodiment, the angle between the magnetization Mpin 45 of the magnetization fixed layer 42 and the magnetization Mfree47 of the magnetization free layer 44 is substantially orthogonal when no stress is applied.
【００４０】磁気抵抗効果素子４４において磁化固着層
４２の磁化Ｍpin４５と磁化自由層４４の磁化Ｍfree４
７との角度により抵抗変化を生ずること、また、応力印
加時の動作についても実施の形態１と同様であるので、
説明を省略する。In the magneto-resistance effect element 44, the magnetization Mpin 45 of the magnetization fixed layer 42 and the magnetization Mfree4 of the magnetization free layer 44
7 and the operation at the time of applying the stress is the same as in the first embodiment.
Description is omitted.
【００４１】本実施の形態２においては、磁気抵抗効果
素子４４の形状を円形としているため、磁化自由層４４
の磁化Ｍfree４７が、印加された応力により回転する
際、どの方向を向いても反磁界係数が同じであるため、
磁化の回転が阻害されることがなくなり、磁気抵抗効果
素子４１の抵抗変化の線形性を向上させることができ
る。In the second embodiment, since the shape of the magnetoresistance effect element 44 is circular, the magnetization free layer 44
When the magnetization Mfree 47 of the above rotates due to the applied stress, the demagnetizing field coefficient is the same in any direction,
The rotation of the magnetization is not hindered, and the linearity of the resistance change of the magnetoresistive element 41 can be improved.
【００４２】本実施の形態２磁気抵抗効果素子４１で
は、抵抗変化は磁化固着層４２の磁化Ｍpin４５と磁化
自由層４４の磁化Ｍfree４７との角度にのみ依存し、磁
気抵抗効果素子４１内の電流の方向には依存せず、か
つ、センス電流は磁気抵抗効果素子４１の膜厚方向に印
加されていることは既に述べた。In the second embodiment, the resistance change of the magneto-resistance effect element 41 depends only on the angle between the magnetization Mpin 45 of the magnetization pinned layer 42 and the magnetization Mfree 47 of the magnetization free layer 44. It has already been described that the sense current is applied in the thickness direction of the magnetoresistive element 41 regardless of the direction.
【００４３】一方、従来例で説明した磁気抵抗効果素子
の場合、抵抗変化は、磁気抵抗効果素子の磁化と電流と
の角度に依存する。図６に示すように、従来の磁気抵抗
効果素子６０に電極６１ａ、および６２ｂを形成した場
合、センス電流６２ａないし６２ｇの角度は磁気抵抗効
果素子６０内分布をもつ。磁気抵抗効果素子６０の磁化
６７が応力印加により、図６に示すような方向に向いた
場合、例えば磁化６７と電流６２ｅのなす角度と、磁化
６７と電流６２ｇのなす角度とは異なることになる。従
って、上記のように、従来例の磁気抵抗効果素子では、
本実施の形態２のように、磁気抵抗効果素子の形状を円
形とすると、磁気抵抗効果素子内での抵抗値は、磁化の
方向に依存するだけでなく、電流の方向にも依存するた
め、応力印加時の抵抗変化を正確に読みとることができ
ない。On the other hand, in the case of the magnetoresistive element described in the conventional example, the resistance change depends on the angle between the magnetization of the magnetoresistive element and the current. As shown in FIG. 6, when electrodes 61a and 62b are formed on a conventional magnetoresistive element 60, the angles of the sense currents 62a to 62g have a distribution in the magnetoresistive element 60. When the magnetization 67 of the magnetoresistive effect element 60 is oriented in the direction shown in FIG. 6 due to the application of stress, for example, the angle formed by the magnetization 67 and the current 62e differs from the angle formed by the magnetization 67 and the current 62g. . Therefore, as described above, in the conventional magnetoresistance effect element,
When the shape of the magnetoresistive element is circular as in the second embodiment, the resistance value in the magnetoresistive element depends not only on the direction of magnetization but also on the direction of current. The resistance change at the time of applying the stress cannot be accurately read.
【００４４】しかし、本実施の形態２における磁気抵抗
効果素子４１は、上述のように、磁化固着層４２の磁化
Ｍpin４５と磁化自由層４４の磁化Ｍfree４７とのなす
角度により抵抗変化を生ずるのであって、電流方向には
依存しないため、応力による抵抗変化のみを出力するこ
とができるという効果を有する。However, in the magnetoresistive element 41 according to the second embodiment, as described above, the resistance changes due to the angle between the magnetization Mpin 45 of the magnetization pinned layer 42 and the magnetization Mfree 47 of the magnetization free layer 44. In addition, since it does not depend on the current direction, there is an effect that only a resistance change due to stress can be output.
【００４５】さらに、実施の形態１でも説明したよう
に、磁気抵抗効果素子の抵抗値を大きくしたい場合、磁
気抵抗効果素子が円形形状をしていれば、従来の磁気抵
抗効果素子では、その抵抗値を大きくすることが困難で
あるが、本実施の形態によれば、円形形状としてもその
直径を小さくするだけで、抵抗値を増大させることは容
易であり、また、絶縁層の厚さによる効果も実施の形態
１と同様である。 （実施の形態３）図７に本発明の実施の形態３における
応力センサーの磁気抵抗効果素子７１を示す。Further, as described in the first embodiment, when it is desired to increase the resistance value of the magnetoresistive effect element, if the magnetoresistive effect element has a circular shape, the resistance of the conventional magnetoresistive effect element is reduced. Although it is difficult to increase the value, according to the present embodiment, it is easy to increase the resistance value only by reducing the diameter of the circular shape, and it depends on the thickness of the insulating layer. The effect is the same as that of the first embodiment. (Embodiment 3) FIG. 7 shows a magnetoresistive element 71 of a stress sensor according to Embodiment 3 of the present invention.
【００４６】磁気抵抗効果素子７１は、実施の形態１と
同様、磁化固着層の磁化を固着する反強磁性層、磁化固
着層、絶縁層、および磁化自由層（図示せず）からなっ
ている。As in the first embodiment, the magnetoresistance effect element 71 includes an antiferromagnetic layer for fixing the magnetization of the magnetization fixed layer, a magnetization fixed layer, an insulating layer, and a magnetization free layer (not shown). .
【００４７】磁気抵抗効果素子７１における磁化自由層
の磁化容易軸７２は、磁気抵抗効果素子７１の長手方向
に設定されており、磁化固着層の磁化（図示せず）は、
磁化容易軸方向７２に直交している。The easy axis 72 of the magnetization free layer of the magneto-resistance effect element 71 is set in the longitudinal direction of the magneto-resistance effect element 71, and the magnetization (not shown) of the magnetization fixed layer is
It is orthogonal to the easy axis direction 72.
【００４８】本実施の形態における磁気抵抗効果素子７
１は、磁化固着層と磁化自由層との間の磁気的相互作用
により層間結合磁界Ｈint７３が磁化自由層に印加され
ている。この層間結合磁界Ｈint７３の大きさは磁化固
着層と磁化自由層との間に形成された絶縁層の膜厚に依
存し、その方向も絶縁層の膜厚に依存し、磁化Ｍpinと
平行な場合と反平行の場合とがある。絶縁層の厚みはＭ
Ｒ比や、磁化自由層のソフト性にも影響を与えるため、
０にできないことがある。The magnetoresistance effect element 7 according to the present embodiment
In 1, an interlayer coupling magnetic field Hint 73 is applied to the magnetization free layer by a magnetic interaction between the magnetization fixed layer and the magnetization free layer. The magnitude of the interlayer coupling magnetic field Hint 73 depends on the thickness of the insulating layer formed between the pinned layer and the free layer, and its direction also depends on the thickness of the insulating layer. And anti-parallel. The thickness of the insulating layer is M
Since it also affects the R ratio and the softness of the magnetization free layer,
Sometimes it cannot be set to 0.
【００４９】そこで、本実施の形態の磁気抵抗効果素子
においては、バイアス磁界Ｈbias７４を印加しており、
バイアス磁界Ｈbias７４の大きさを層間結合磁界Ｈint
７３と略同一で、方向は層間結合磁界Ｈint７３と逆方
向に設定している。Therefore, in the magnetoresistive element of this embodiment, a bias magnetic field Hbias 74 is applied,
The magnitude of the bias magnetic field Hbias 74 is determined by the interlayer coupling magnetic field Hint.
The direction is substantially the same as 73 and the direction is set opposite to the direction of the interlayer coupling magnetic field Hint 73.
【００５０】バイアス磁界Ｈbias７４が印加されない場
合は、無応力時、磁化自由層の磁化Ｍfree７５は、層間
結合磁界Ｈint７３の影響により、磁化容易軸方向から
はずれた方向に向く。このため、無応力時には磁化固着
層の磁化Ｍpinと磁化自由層の磁化Ｍfree７５は直交し
ない。このとき、応力を磁化固着層の磁化方向に対し、
＋４５゜（矢印７６）または−４５゜（矢印７７）方向
に印加すると、磁気抵抗効果素子７１の抵抗変化は応力
の正負に対して非対称となる。When no bias magnetic field Hbias 74 is applied, when no stress is applied, the magnetization Mfree75 of the magnetization free layer is directed in a direction deviated from the easy axis direction due to the effect of the interlayer coupling magnetic field Hint73. Therefore, when there is no stress, the magnetization Mpin of the magnetization fixed layer and the magnetization Mfree75 of the magnetization free layer are not orthogonal. At this time, the stress is applied to the magnetization direction of the magnetization pinned layer.
When the voltage is applied in the + 45 ° (arrow 76) or −45 ° (arrow 77) direction, the resistance change of the magnetoresistive element 71 becomes asymmetric with respect to the positive or negative of the stress.
【００５１】しかしながら、本実施の形態においては、
バイアス磁界Ｈbias７４により、層間結合磁界Ｈint７
３が打ち消されているため、無応力時の磁化自由層の磁
化Ｍfree７５は磁化容易軸方向に向き、磁化固着層の磁
化Ｍpinと磁化自由層の磁化Ｍfree７５とは直交するた
め、応力を磁化固着層の磁化方向に対し、＋４５゜(矢
印７６)または−４５゜（矢印７７）方向に印加した場
合、磁気抵抗効果素子７１の抵抗変化は応力の正負に対
して対称性の良好なものとなる。 （実施の形態４）図８に本発明の実施の形態３における
応力センサーの磁気抵抗効果素子８１を示す。However, in the present embodiment,
The bias magnetic field Hbias 74 causes the interlayer coupling magnetic field Hint7.
3, the magnetization Mfree75 of the magnetization free layer at the time of no stress is oriented in the easy axis direction, and the magnetization Mpin of the magnetization fixed layer is orthogonal to the magnetization Mfree75 of the magnetization free layer. When applied in the + 45 ° (arrow 76) or −45 ° (arrow 77) direction with respect to the magnetization direction, the resistance change of the magnetoresistive effect element 71 has good symmetry with respect to the positive or negative of the stress. (Embodiment 4) FIG. 8 shows a magnetoresistive element 81 of a stress sensor according to Embodiment 3 of the present invention.
【００５２】磁気抵抗効果素子８１は、実施の形態１と
同様、磁化固着層の磁化を固着する反強磁性層、磁化固
着層、絶縁層、および磁化自由層（図示せず）からなっ
ている。センス電流については電極（図示せず）によ
り、磁気抵抗効果素子８１の膜厚方向に印加されてい
る。As in the first embodiment, the magnetoresistance effect element 81 includes an antiferromagnetic layer for fixing the magnetization of the magnetization fixed layer, a magnetization fixed layer, an insulating layer, and a magnetization free layer (not shown). . The sense current is applied in the thickness direction of the magnetoresistive element 81 by an electrode (not shown).
【００５３】磁気抵抗効果素子８１における磁化自由層
の磁化容易軸８２は、磁気抵抗効果素子８１の長手方向
に設定されており、磁化固着層の磁化（図示せず）は、
磁化自由層の容易軸に対してαの角度だけ傾いている。
このような構成を有する応力センサーにおいて本実施の
形態４でがバイアス磁界Ｈbias８４を磁化容易軸８２と
同方向に印加している。The easy axis 82 of the magnetization free layer of the magnetoresistive element 81 is set in the longitudinal direction of the magnetoresistive element 81, and the magnetization (not shown) of the magnetization fixed layer is
It is inclined by an angle α with respect to the easy axis of the magnetization free layer.
In the stress sensor having such a configuration, in the fourth embodiment, the bias magnetic field Hbias 84 is applied in the same direction as the axis of easy magnetization 82.
【００５４】磁気抵抗効果素子８１は、磁化固着層と磁
化自由層との間で、磁気的相互作用を生じ、磁化自由層
に層間結合磁界Ｈint８３を与える。層間結合磁界Ｈint
８３は絶縁層の厚みに依存し、０である場合や、磁化固
着層の磁化方向に平行な場合、または反平行な場合があ
る。絶縁層の厚みはＭＲ比や、磁化自由層のソフト性に
も影響を与えるため、０にできないことがある。The magnetoresistance effect element 81 causes a magnetic interaction between the magnetization fixed layer and the magnetization free layer, and applies an interlayer coupling magnetic field Hint 83 to the magnetization free layer. Interlayer coupling magnetic field Hint
83 depends on the thickness of the insulating layer, and may be 0, parallel to the magnetization direction of the magnetization fixed layer, or antiparallel. Since the thickness of the insulating layer affects the MR ratio and the softness of the magnetization free layer, it may not be possible to set the thickness to zero.
【００５５】応力の印加に対して、抵抗変化の線形性を
向上させるためには、磁化固着層の磁化と磁化自由層の
無応力時の磁化Mfree８５方向とを直交させることが有
効である。In order to improve the linearity of the resistance change with respect to the application of stress, it is effective to make the magnetization of the magnetization fixed layer perpendicular to the magnetization Mfree 85 direction of the magnetization free layer when no stress is applied.
【００５６】そこで本実施の形態４では、磁化固着層の
磁化と磁化自由層の無応力時の磁化Mfree８５とを直交
させるため、磁化自由層の異方性磁界をＨkとし、容易
軸と層間結合磁界Ｈintとの角度をα（図８）とし、磁
化自由層の異方性磁界をＨkとしたとき、Therefore, in the fourth embodiment, in order to make the magnetization of the magnetization fixed layer orthogonal to the magnetization Mfree 85 of the magnetization free layer when no stress is applied, the anisotropic magnetic field of the magnetization free layer is set to Hk, and the easy axis and the interlayer coupling are set. When the angle to the magnetic field Hint is α (FIG. 8) and the anisotropic magnetic field of the magnetization free layer is Hk,
【００５７】式１ Ｈkcosαsinα＋Ｈbiascosα＋Ｈint＝０ を略満たすように、容易軸と層間結合磁界Ｈint８３と
の角度αと、バイアス磁界Ｈbias８４とを設定してい
る。これにより、無応力時の磁化自由層の磁化Ｍfree８
５を磁化固着層の磁化と直交させることができる。以下
にその理由を説明する。Equation 1 The angle α between the easy axis and the interlayer coupling magnetic field Hint 83 and the bias magnetic field Hbias 84 are set so as to substantially satisfy Hkcosαsinα + Hbiascosα + Hint = 0. Thereby, the magnetization Mfree8 of the magnetization free layer at the time of no stress
5 can be made orthogonal to the magnetization of the magnetization fixed layer. The reason will be described below.
【００５８】磁化自由層の磁化Ｍfree８５の無応力時の
方向θは、磁化自由層の異方性エネルギー定数Ｋuと磁
化自由層に印加された磁界（層間結合磁界Ｈintとバイ
アス磁界Ｈbias）とに依存し、磁化自由層の磁気的エネ
ルギーＥを考えることにより、その方向を求めることが
できる。磁化容易軸８２と磁化Ｍfree８５との角度をθ
（図８）、磁化自由層の飽和磁化をＭsとすると、磁気
的エネルギーＥはThe direction θ of the magnetization Mfree 85 of the magnetization free layer at the time of no stress depends on the anisotropic energy constant Ku of the magnetization free layer and the magnetic field (interlayer coupling magnetic field Hint and bias magnetic field Hbias) applied to the magnetization free layer. Then, by considering the magnetic energy E of the magnetization free layer, the direction can be obtained. The angle between the easy magnetization axis 82 and the magnetization Mfree 85 is θ
(FIG. 8), assuming that the saturation magnetization of the magnetization free layer is Ms, the magnetic energy E is
【００５９】式２ Ｅ＝Ｋu×sin2θ−Ｍs×Ｈint×cos（α−θ）−Ｍs×
Ｈbias×cosθ となる。磁化自由層の磁化Ｍfree８５の方向θは、磁気
的エネルギーＥが安定なときであるから、エネルギーＥ
をθについて微分したものが０となるときであり、エネ
ルギーＥをθについて２階微分したものが正の時であ
る。即ち、[0059] Formula 2 E = Ku × sin 2 θ -Ms × Hint × cos (α-θ) -Ms ×
Hbias × cosθ. The direction θ of the magnetization Mfree85 of the magnetization free layer is when the magnetic energy E is stable,
Is obtained when 0 is differentiated with respect to θ, and is obtained when the energy E is second-order differentiated with respect to θ. That is,
【００６０】式３ Ｅ´＝２Ｋu×sinθ×cosθ−Ｍs×Ｈint×sin（α−
θ）−Ｍs×Ｈbias×sinθ＝０ 異方性エネルギー定数Ｋuは（Ｈk×Ｍs／２）であるか
ら、上式は、Equation 3 E '= 2 Ku × sin θ × cos θ−Ms × Hint × sin (α−
θ) −Ms × Hbias × sin θ = 0 Since the anisotropic energy constant Ku is (Hk × Ms / 2),
【００６１】式４ Ｈk×sinθ×cosθ−Ｈint×sin（α−θ）−Ｈbias×s
inθ＝０ である。Equation 4 Hk × sin θ × cos θ−Hint × sin (α−θ) −Hbias × s
inθ = 0.
【００６２】層間結合磁界Ｈint８３と磁化固着層の磁
化とは平行あるいは反平行であるので、磁化固着層の磁
化と磁化自由層の磁化Ｍfree８５とが直交するというこ
とは、Since the interlayer coupling magnetic field Hint 83 and the magnetization of the magnetization fixed layer are parallel or antiparallel, the fact that the magnetization of the magnetization fixed layer and the magnetization Mfree85 of the magnetization free layer are orthogonal to each other means that
【００６３】式５ α−θ＝９０゜ であるので、式４と式５より、式１が得られる。なお、
エネルギーのθに関する２階微分が正であることより、Equation 5 Since α−θ = 90 °, Equation 1 is obtained from Equations 4 and 5. In addition,
Since the second derivative of energy with respect to θ is positive,
【００６４】式６ −Hk×cos(2α)＋Hbias×sinα＞０を満たす。Equation 6 −Hk × cos (2α) + Hbias × sinα> 0 is satisfied.
【００６５】従って、式１、式６を満たすように、磁化
容易軸８２と層間結合磁界Ｈint８３との角度αとバイ
アス磁界Ｈbias８４を設定すれば、磁化固着層の磁化と
磁化自由層の磁化Ｍfreeが直交する。Therefore, if the angle α between the easy axis 82 and the interlayer coupling magnetic field Hint 83 and the bias magnetic field Hbias 84 are set so as to satisfy the equations 1 and 6, the magnetization of the pinned layer and the magnetization Mfree of the magnetization free layer are set. Orthogonal.
【００６６】次に動作について説明する応力は層間結合
磁界Ｈint（磁化固着層の磁化方向）に対して、＋４５
゜あるいは−４５゜の方向（図８中、矢印８６、および
８７）に印加する。The stress for explaining the operation is +45 with respect to the interlayer coupling magnetic field Hint (the magnetization direction of the magnetization fixed layer).
It is applied in the direction of {or −45} (arrows 86 and 87 in FIG. 8).
【００６７】磁化自由層の磁歪定数が正で、引っ張り応
力が矢印８６方向へ印加されると、磁歪の逆効果で矢印
８６に異方性エネルギーＥσが生じるため、磁化自由層
の磁化Ｍfree８５は、図８中時計方向に回転する。従っ
て、磁化自由層の磁化Ｍfree８５と磁化固着層の磁化と
の角度が９０゜より大きくなるため、磁気抵抗効果素子
８１の抵抗値が増加する。When the magnetostriction constant of the magnetization free layer is positive and a tensile stress is applied in the direction of arrow 86, an anisotropic energy Eσ is generated in arrow 86 due to the opposite effect of magnetostriction. It rotates clockwise in FIG. Therefore, since the angle between the magnetization Mfree85 of the magnetization free layer and the magnetization of the magnetization fixed layer becomes larger than 90 °, the resistance value of the magnetoresistance effect element 81 increases.
【００６８】圧縮応力が矢印８６方向へ印加されると、
磁歪の逆効果で矢印８７に異方性エネルギーＥσが生じ
るため、磁化自由層の磁化Ｍfree８５は、反時計方向に
回転する。従って、磁化自由層の磁化Ｍfree８５と磁化
固着層の磁化との角度が９０゜より小さくなるため、磁
気抵抗効果素子８１の抵抗値が減少する。When compressive stress is applied in the direction of arrow 86,
Since the anisotropic energy Eσ is generated at the arrow 87 due to the opposite effect of the magnetostriction, the magnetization Mfree85 of the magnetization free layer rotates in the counterclockwise direction. Therefore, the angle between the magnetization Mfree85 of the magnetization free layer and the magnetization of the magnetization fixed layer becomes smaller than 90 °, and the resistance value of the magnetoresistive element 81 decreases.
【００６９】引っ張り応力が矢印８７方向へ印加される
と、磁歪の逆効果で矢印８７に異方性エネルギーＥσが
生じるため、磁化自由層の磁化Ｍfree８５は、図８中反
時計方向に回転する。従って、磁化自由層の磁化Ｍfree
８５と磁化固着層の磁化との角度が９０゜より小さくな
るため、磁気抵抗効果素子８１の抵抗値が減少する。When a tensile stress is applied in the direction of arrow 87, anisotropic energy Eσ is generated in arrow 87 due to the opposite effect of magnetostriction, so that magnetization Mfree85 of the magnetization free layer rotates counterclockwise in FIG. Therefore, the magnetization Mfree of the magnetization free layer
Since the angle between 85 and the magnetization of the magnetization fixed layer becomes smaller than 90 °, the resistance value of the magnetoresistive element 81 decreases.
【００７０】圧縮応力が矢印８７方向へ印加されると、
磁歪の逆効果で矢印８６に異方性エネルギーＥσが生じ
るため、磁化自由層の磁化Ｍfree８５は、時計方向に回
転する。従って、磁化自由層の磁化Ｍfree８５と磁化固
着層の磁化との角度が９０゜より大きくなるため、磁気
抵抗効果素子８１の抵抗値が増加する。When compressive stress is applied in the direction of arrow 87,
Since the anisotropic energy Eσ is generated at the arrow 86 due to the opposite effect of the magnetostriction, the magnetization Mfree85 of the magnetization free layer rotates clockwise. Therefore, since the angle between the magnetization Mfree85 of the magnetization free layer and the magnetization of the magnetization fixed layer becomes larger than 90 °, the resistance value of the magnetoresistance effect element 81 increases.
【００７１】層間結合磁界Ｈintが２４０Ａ／ｍ（＝３O
e）、異方性磁界Ｈkが４００Ａ／ｍ（＝５Ｏｅ）である
とき、αを１１８゜、バイアス磁界Ｈbiasを１６０Ａ／
ｍ（＝２Ｏｅ）とすると、式１、および式６を満足し、
このときの抵抗変化は図９になる。なお、応力は矢印８
６方向に印加した。The interlayer coupling magnetic field Hint is 240 A / m (= 3O
e), when the anisotropic magnetic field Hk is 400 A / m (= 5 Oe), α is 118 ° and the bias magnetic field Hbias is 160 A / m.
m (= 2Oe), Equations 1 and 6 are satisfied,
FIG. 9 shows the resistance change at this time. The stress is indicated by arrow 8
The voltage was applied in six directions.
【００７２】応力印加時の動作については第１の実施の
形態と同様であるので、説明を省略する。The operation at the time of applying the stress is the same as that of the first embodiment, and the description is omitted.
【００７３】バイアス磁界Ｈbias８４の印加手段につい
て説明する。本実施の形態において、バイアス磁界は図
１０に示すように、磁気抵抗効果素子８１の両側に永久
磁石１０１ａ、および１０１ｂを配置し、バイアス磁界
を印加することができる（図１０（ａ））。また、磁気
抵抗効果素子８１の両側に、磁気抵抗効果素子８１に接
して、硬質磁性膜１０２ａ、および１０２ｂを形成し、
バイアス磁界を印加することができる（図１０
（ｂ））。さらには、磁気抵抗効果素子８１の磁化自由
層に接して、反響磁性膜１０３を磁気抵抗効果素子８１
上に形成して、バイアス磁界を印加することができる
（図１０（ｃ））。なお、図１０（ａ）の方法において
は、永久磁石の材料、および間隔を任意に設定できるの
で、バイアス磁界Ｈbias８４の大きさを任意に設定する
ことができる。また、図１０（ｂ）、および図１０
（ｃ）の方法においても、硬質磁性膜、および反強磁性
膜の材料、および膜厚を変更することで、バイアス磁界
Ｈbias８４の大きさを任意に設定することができる。The means for applying the bias magnetic field Hbias 84 will be described. In this embodiment, as shown in FIG. 10, the bias magnetic field can be applied by disposing permanent magnets 101a and 101b on both sides of the magnetoresistive element 81 as shown in FIG. 10 (FIG. 10A). Hard magnetic films 102a and 102b are formed on both sides of the magnetoresistive element 81 in contact with the magnetoresistive element 81,
A bias magnetic field can be applied (FIG. 10).
(B)). Further, in contact with the magnetization free layer of the magneto-resistance effect element 81,
A bias magnetic field can be applied to the upper electrode (FIG. 10C). In the method of FIG. 10A, since the material and the interval of the permanent magnet can be arbitrarily set, the magnitude of the bias magnetic field Hbias 84 can be arbitrarily set. 10 (b) and FIG.
Also in the method (c), the magnitude of the bias magnetic field Hbias 84 can be arbitrarily set by changing the material and thickness of the hard magnetic film and the antiferromagnetic film.
【００７４】また、このバイアス磁界により、磁化自由
層を単磁区構造とすることが可能であるため、磁壁の不
連続異動に起因するバルクハウゼンノイズを低減すると
いう効果も有する。Further, since the magnetization free layer can have a single domain structure by the bias magnetic field, there is also an effect of reducing Barkhausen noise caused by discontinuous transfer of the domain wall.
【００７５】従来例には、バイアス磁界を印加するもの
が記載されているが、従来例の場合、このバイアス磁界
により、磁気抵抗効果素子の磁化回転は阻害されるた
め、抵抗変化量が図７に示した場合よりもさらに小さく
なるため、バイアス磁界の印加した場合の抵抗変化につ
いては、本実施の形態の方が効果がある。In the conventional example, a bias magnetic field is applied. However, in the conventional example, since the magnetization rotation of the magnetoresistive element is inhibited by the bias magnetic field, the resistance change amount is reduced as shown in FIG. Therefore, the present embodiment is more effective in changing the resistance when a bias magnetic field is applied.
【００７６】なお、本実施の形態では、磁気抵抗効果素
子８１の形状を長方形形状としたが、第２の実施の形態
に記載したように円形とした場合においても、実施の形
態２の効果が得られることは言うまでもない。In the present embodiment, the shape of the magnetoresistive element 81 is rectangular, but the effect of the second embodiment can be obtained even when the magnetoresistive element 81 is circular as described in the second embodiment. It goes without saying that you can get it.
【００７７】さらに、実施の形態１、実施の形態２、お
よび実施の形態３において磁化容易軸方向にバイアス磁
界を印加することにより、実施の形態４と同様にバルク
ハウゼンノイズを低減できる。Further, by applying a bias magnetic field in the easy axis direction in the first, second, and third embodiments, Barkhausen noise can be reduced as in the fourth embodiment.
【００７８】このバイアス磁界や、実施の形態３で説明
したバイアス磁界は、図１０で説明したバイアス磁界印
加手段を用いることができるのは言うまでもない。 （実施の形態５）図１１（ａ）に、本発明の実施の形態
５における応力センサーの磁気抵抗効果素子１１１を示
す。It is needless to say that the bias magnetic field applying means described with reference to FIG. 10 can be used for this bias magnetic field and the bias magnetic field described in the third embodiment. Embodiment 5 FIG. 11A shows a magnetoresistive element 111 of a stress sensor according to Embodiment 5 of the present invention.
【００７９】磁気抵抗効果素子１１１は、実施の形態１
と同様、磁化固着層の磁化を固着する反強磁性層、磁化
固着層、絶縁層、および磁化自由層（図示せず）からな
っている。The magnetoresistive element 111 according to the first embodiment
Similarly to the above, it is composed of an antiferromagnetic layer for fixing the magnetization of the magnetization fixed layer, a magnetization fixed layer, an insulating layer, and a magnetization free layer (not shown).
【００８０】磁気抵抗効果素子１１１の磁化自由層の磁
化容易軸１１２は、磁気抵抗効果素子１１１の長手方向
に設定されており、磁化固着層の磁化（図示せず）は、
磁化自由層の容易軸に対して略直交している。磁気抵抗
効果素子１１１にはバイアス磁界Ｈbias１１４が磁化容
易軸１１２と同方向に印加されている。The easy axis 112 of the magnetization free layer of the magnetoresistance effect element 111 is set in the longitudinal direction of the magnetoresistance effect element 111, and the magnetization (not shown) of the magnetization fixed layer is
It is substantially perpendicular to the easy axis of the magnetization free layer. A bias magnetic field Hbias 114 is applied to the magnetoresistive element 111 in the same direction as the easy axis 112.
【００８１】磁気抵抗効果素子１１１は、磁化固着層と
磁化自由層との間で、磁気的相互作用を生じ、磁化自由
層に層間結合磁界Ｈint１１３を与える。これは、実施
の形態３で説明したものと同様で、磁化固着層の磁化方
向に平行、あるいは反平行である。従って、層間結合磁
界Ｈint１１３は磁化自由層の磁化容易軸１１２に対し
て略直交している。The magnetoresistance effect element 111 causes a magnetic interaction between the magnetization fixed layer and the magnetization free layer, and applies an interlayer coupling magnetic field Hint 113 to the magnetization free layer. This is similar to that described in the third embodiment, and is parallel or anti-parallel to the magnetization direction of the magnetization fixed layer. Therefore, the interlayer coupling magnetic field Hint 113 is substantially perpendicular to the easy axis 112 of the magnetization free layer.
【００８２】応力の印加に対して、抵抗変化の線形性を
向上させるためには、無応力時における磁化自由層の磁
化方向に対し＋４５゜、あるいは−４５゜の方向に応力
を、印加することが有効である。In order to improve the linearity of the resistance change with respect to the application of the stress, it is necessary to apply the stress in the direction of + 45 ° or −45 ° with respect to the magnetization direction of the magnetization free layer at the time of no stress. Is valid.
【００８３】図１１（ａ）においては、応力印加方向１
１６、および１１７は無応力時の磁化自由層の磁化Ｍfr
ee１１５の方向に対し、＋４５゜、あるいは−４５゜の
角度を有している。In FIG. 11A, the stress application direction 1
16 and 117 are the magnetization Mfr of the magnetization free layer under no stress
It has an angle of + 45 ° or −45 ° with respect to the direction of ee115.
【００８４】このような方向に応力印加することで、抵
抗変化の線形性が向上する理由を説明する。The reason why the linearity of the resistance change is improved by applying the stress in such a direction will be described.
【００８５】実施の形態３のところで説明したように、
層間結合磁界Ｈintが存在するとき、これを打ち消すＨb
ias磁界を与えないときは、磁化自由層の方向は磁化容
易軸からずれたところに向き、磁化固着層の磁化Ｍpin
と磁化自由層の磁化Ｍfree１１５とは直交しない。この
ときの磁化自由層の磁化Ｍfree１１５と磁化容易軸１１
２との角度をθ（図１１（ｂ））とする。As described in the third embodiment,
When there is an interlayer coupling magnetic field Hint, it is canceled by Hb.
When no ias magnetic field is applied, the direction of the magnetization free layer is shifted from the axis of easy magnetization, and the magnetization Mpin of the magnetization fixed layer is
Is not orthogonal to the magnetization Mfree 115 of the magnetization free layer. At this time, the magnetization Mfree 115 of the magnetization free layer and the easy axis 11
The angle with 2 is assumed to be θ (FIG. 11B).
【００８６】この状態で、応力を磁化固着層の磁化Ｍpi
nの方向に対して、＋４５゜、あるいは−４５゜の方向
に印加する（図１１（ｂ）応力印加方向１１８、および
１１９）。In this state, the stress is applied to the magnetization Mpi of the magnetization fixed layer.
The voltage is applied in the direction of + 45 ° or −45 ° with respect to the direction of n (FIG. 11B, stress application directions 118 and 119).
【００８７】応力の印加により、異方性エネルギーが応
力印加方向１１９に印加されたとき、磁化自由層の磁化
Ｍfree１１５は、最大（４５゜−θ）回転し、異方性エ
ネルギーが応力印加方向１１８に印加されたとき、磁化
自由層の磁化Ｍfree１１５は最大（４５°＋θ）回転す
ることになる。応力による異方性エネルギーの出現する
方向が、応力印加方向１１８あるいは１１９になること
は、印加応力が正であるか、または負であるかに対応
し、磁化自由層の磁化Ｍfree１１５の回転角度が印加応
力の正負で異なることになる。When the anisotropic energy is applied in the stress application direction 119 by the application of the stress, the magnetization Mfree 115 of the magnetization free layer is rotated by a maximum (45 ° −θ), and the anisotropic energy is changed in the stress application direction 118. , The magnetization Mfree 115 of the magnetization free layer is rotated by a maximum (45 ° + θ). The direction in which the anisotropic energy due to the stress appears in the stress application direction 118 or 119 corresponds to whether the applied stress is positive or negative, and the rotation angle of the magnetization Mfree 115 of the magnetization free layer is changed. It differs depending on whether the applied stress is positive or negative.
【００８８】従って、抵抗変化の線形性を劣化させるこ
とになるが、図１１（ａ）のように、印加応力を無応力
時の磁化自由層の磁化Ｍfree１１５方向に対して＋４５
゜あるいは、−４５゜の方向に印加することにより、磁
化自由層の磁化Ｍfreeの回転量が、印加応力の正負で異
なることはない。よって、抵抗変化の線形性を向上させ
ることができる。Therefore, although the linearity of the resistance change is degraded, as shown in FIG. 11A, the applied stress is increased by +45 with respect to the direction of the magnetization Mfree 115 of the magnetization free layer when no stress is applied.
By applying in the direction of {or −45}, the rotation amount of the magnetization Mfree of the magnetization free layer does not differ depending on whether the applied stress is positive or negative. Therefore, the linearity of the resistance change can be improved.
【００８９】無応力時の磁化自由層の磁化Ｍfree１１５
の方向は、以下のようにして知ることができる。The magnetization Mfree 115 of the magnetization free layer under no stress
Can be known as follows.
【００９０】つまり、磁化自由層の異方性磁界をＨkと
し、無応力時の磁化自由層の磁化Ｍfree１１５が磁化容
易軸１１２に対し角度θ（図１１（ａ））であるとき、
角度θはThat is, when the anisotropic magnetic field of the magnetization free layer is Hk, and the magnetization Mfree 115 of the magnetization free layer under no stress is at an angle θ (FIG. 11A) with respect to the easy axis 112,
Angle θ
【００９１】式７ Ｈk×cosθ×sinθ＋Ｈbias×sinθ−Ｈint×cosθ＝０ Hkcos(2θ)+Hbiascosθ＋Hintsinθ＞０ を満たす。Equation 7 Hk × cos θ × sin θ + Hbias × sin θ−Hint × cos θ = 0 Hkcos (2θ) + Hbiascos θ + Hintsin θ> 0.
【００９２】この関係式は、実施の形態４で説明したよ
うに、磁気的なエネルギーを考慮することで得られる。This relational expression is obtained by considering magnetic energy as described in the fourth embodiment.
【００９３】従って、異方性磁界Hk、層間結合磁界Ｈin
tは磁気抵抗効果素子１１１の初期特性を測定すること
で知ることができ、バイアス磁界Ｈbiasも自由に設定で
きるため、既知となるので、式７から容易に角度θを求
めることができるため、応力印加方向をこのθに対して
＋４５゜、あるいは−４５゜の方向に設定することは容
易である。Therefore, the anisotropic magnetic field Hk and the interlayer coupling magnetic field Hin
t can be known by measuring the initial characteristics of the magnetoresistive effect element 111, and the bias magnetic field Hbias can be set freely. Therefore, the value of t is known. It is easy to set the application direction to + 45 ° or −45 ° with respect to θ.
【００９４】次に動作について説明する。Next, the operation will be described.
【００９５】本実施の形態における磁気抵抗効果素子１
１１の層間結合磁界Ｈintが２４０Ａ／ｍ（＝３Oe）、
異方性磁界Ｈkが４００Ａ／ｍ（＝５Ｏｅ）であると
き、バイアス磁界Ｈbiasを１６０Ａ／ｍ（＝２Ｏｅ）と
すると、θは２４．６゜となるので、応力印加方向を磁
化容易軸１１２に対して−２０．４゜（＝２４．６゜−
４５゜、図１１中矢印１１６）とする。磁気抵抗効果素
子１１１の磁化自由層の磁歪定数が正であれば、引っ張
り応力が矢印１１６に印加されると、磁歪の逆効果によ
り、矢印１１６の方向に異方性エネルギーが発生し、磁
化自由層の磁化Ｍfree１１５は時計回りに回転する。磁
化固着層の磁化方向と、層間結合磁界Ｈintが平行であ
れば、上記の回転により、磁化固着層の磁化と磁化自由
層の磁化Ｍfree１１５との角度が大きくなるため、磁気
抵抗効果素子１１１の抵抗値は増加し、矢印１１６の方
向に圧縮応力が印加されると、矢印１１７の方向に異方
性エネルギーが発生するため、磁化自由層の磁化Ｍfree
１１５は反時計回りに回転し、磁化固着層の磁化と磁化
自由層の磁化Ｍfree１１５との角度が小さくなるため、
磁気抵抗効果素子１１１の抵抗値は減少する。The magnetoresistance effect element 1 according to the present embodiment
11, the interlayer coupling magnetic field Hint is 240 A / m (= 3 Oe),
When the anisotropic magnetic field Hk is 400 A / m (= 5 Oe) and the bias magnetic field Hbias is 160 A / m (= 2 Oe), θ becomes 24.6 °. On the other hand, -20.4 ° (= 24.6 °-
45 °, and arrow 116 in FIG. 11). If the magnetostriction constant of the magnetization free layer of the magnetoresistance effect element 111 is positive, when a tensile stress is applied to the arrow 116, anisotropic energy is generated in the direction of the arrow 116 due to the opposite effect of magnetostriction, and The magnetization Mfree 115 of the layer rotates clockwise. If the magnetization direction of the magnetization fixed layer is parallel to the interlayer coupling magnetic field Hint, the angle described above increases the angle between the magnetization of the magnetization fixed layer and the magnetization Mfree 115 of the magnetization free layer. The value increases, and when a compressive stress is applied in the direction of arrow 116, anisotropic energy is generated in the direction of arrow 117, so that the magnetization Mfree of the magnetization free layer
115 rotates counterclockwise, and the angle between the magnetization of the magnetization fixed layer and the magnetization Mfree 115 of the magnetization free layer becomes small.
The resistance value of the magneto-resistance effect element 111 decreases.
【００９６】引っ張り応力が上記θに対して−４５゜
（矢印１１７）に印加されたときは、矢印１１７の方向
に異方性エネルギーが発生するため、磁化自由層の磁化
Ｍfree１１５は反時計回りに回転し、磁化固着層の磁化
と磁化自由層の磁化Ｍfree１１５との角度が小さくなる
ため、磁気抵抗効果素子１１１の抵抗値は減少し、圧縮
応力が矢印１１７に印加されたときは、矢印１１６の方
向に異方性エネルギーが発生し、磁化自由層の磁化Ｍfr
ee１１５は時計回りに回転し、磁化固着層の磁化と磁化
自由層の磁化Ｍ１１５との角度が大きくなるため、磁気
抵抗効果素子１１１の抵抗値は増加する。When the tensile stress is applied at -45 ° to the above θ (arrow 117), anisotropic energy is generated in the direction of arrow 117, so that the magnetization Mfree 115 of the magnetization free layer rotates counterclockwise. Rotation causes the angle between the magnetization of the magnetization pinned layer and the magnetization Mfree 115 of the magnetization free layer to decrease, so that the resistance value of the magnetoresistive element 111 decreases. Energy is generated in the direction, and the magnetization Mfr of the magnetization free layer is generated.
Since ee 115 rotates clockwise and the angle between the magnetization of the magnetization fixed layer and the magnetization M 115 of the magnetization free layer increases, the resistance value of the magnetoresistive element 111 increases.
【００９７】磁気抵抗効果素子１１１の磁化自由層の磁
歪定数を5×10-6としたときの応力に対する抵抗変化率
を図１２に示す。なお、応力は矢印１１８方向に印加し
た。図１２には従来の磁気抵抗効果素子の場合を合わせ
て示している。本実施の形態のほうが高い抵抗変化率を
示していることがわかる。FIG. 12 shows the rate of change in resistance with respect to stress when the magnetostriction constant of the magnetization free layer of the magnetoresistance effect element 111 is 5 × 10 −6 . The stress was applied in the direction of arrow 118. FIG. 12 also shows the case of a conventional magnetoresistance effect element. It can be seen that the present embodiment shows a higher rate of resistance change.
【００９８】なお、バイアス磁界を本実施の形態のよう
に、磁化容易軸方向に印加するのではなく、任意の方向
に印加する場合においても、任意の方向に印加するバイ
アス磁界を磁化容易軸方向の成分と、層間結合磁界Ｈin
tとに平行な成分に分離し、磁化容易軸方向の成分を新
たに式７のＨbiasとし、層間結合磁界Ｈintに平行な成
分と層間結合磁界Ｈintとの合計を新たに式７のＨintと
して、角度θを求めることができる。In the case where the bias magnetic field is not applied in the direction of the easy axis as in this embodiment, but is applied in any direction, the bias magnetic field applied in the arbitrary direction may be applied in the direction of the easy axis. And the interlayer coupling magnetic field Hin
The component in the direction of the easy axis is newly defined as Hbias in Equation 7, and the sum of the component parallel to the interlayer coupling magnetic field Hint and the interlayer coupling magnetic field Hint is newly defined as Hint in Equation 7. Angle θ can be determined.
【００９９】バイアス磁界の印加方法等については実施
の形態３と同様であるので、説明を省略する。また、バ
イアス磁界に印加によりバルクハウゼンノイズを低減で
きること、磁気抵抗効果素子１１１を円形形状にするこ
とについても実施の形態２と同様である。The method of applying the bias magnetic field and the like are the same as those in the third embodiment, and a description thereof will not be repeated. In addition, the Barkhausen noise can be reduced by applying a bias magnetic field, and the magnetoresistive element 111 has a circular shape in the same manner as in the second embodiment.
【０１００】[0100]
【発明の効果】以上のように本発明の応力センサーは、
磁化固着層と、絶縁層と、磁化自由層とを順次積層して
なる磁気抵抗効果素子、即ち、ＧＭＲ素子を用いること
により、応力による抵抗変化率が高い応力センサーを得
ることができる。As described above, the stress sensor of the present invention is
By using a magnetoresistive element in which a magnetization fixed layer, an insulating layer, and a magnetization free layer are sequentially stacked, that is, a GMR element, a stress sensor having a high rate of change in resistance due to stress can be obtained.
【０１０１】また、磁気抵抗効果素子の磁化固着層と磁
化自由層との間に層間結合磁界が発生する場合において
も、バイアス磁界の印加と、磁化固着層の磁化方向と磁
化自由層の磁化容易軸とを適切に設定することにより、
線形性の良い出力を得ることができる。Further, even when an interlayer coupling magnetic field is generated between the magnetization fixed layer and the magnetization free layer of the magnetoresistive effect element, the application of the bias magnetic field, the magnetization direction of the magnetization fixed layer, and the easy magnetization of the magnetization free layer are performed. By setting the axis properly
An output with good linearity can be obtained.
【図１】本発明の実施の形態１における応力センサーの
平面図である。FIG. 1 is a plan view of a stress sensor according to Embodiment 1 of the present invention.
【図２】本発明の実施の形態１における磁気抵抗効果素
子の構成図である。FIG. 2 is a configuration diagram of a magnetoresistive element according to Embodiment 1 of the present invention.
【図３】本発明の実施の形態１における磁気抵抗効果素
子の応力と抵抗変化率の関係を示す図である。FIG. 3 is a diagram showing the relationship between the stress and the rate of change in resistance of the magnetoresistance effect element according to the first embodiment of the present invention.
【図４】本発明の実施の形態２における応力センサーの
平面図である。FIG. 4 is a plan view of a stress sensor according to Embodiment 2 of the present invention.
【図５】本発明の実施の形態２における磁気抵抗効果素
子の構成図である。FIG. 5 is a configuration diagram of a magnetoresistive element according to a second embodiment of the present invention.
【図６】本発明の実施の形態２における応力センサーの
平面図である。FIG. 6 is a plan view of a stress sensor according to Embodiment 2 of the present invention.
【図７】本発明の実施の形態３における応力センサーの
平面図である。FIG. 7 is a plan view of a stress sensor according to Embodiment 3 of the present invention.
【図８】本発明の実施の形態４における応力センサーの
平面図である。FIG. 8 is a plan view of a stress sensor according to Embodiment 4 of the present invention.
【図９】本発明の実施の形態４における磁気抵抗効果素
子の応力と抵抗変化率の関係を示す図である。FIG. 9 is a diagram showing a relationship between a stress and a rate of change in resistance of a magnetoresistive element according to a fourth embodiment of the present invention.
【図１０】本発明の実施の形態４におけるバイアス磁界
印加の構成の例である。FIG. 10 is an example of a configuration for applying a bias magnetic field according to a fourth embodiment of the present invention.
【図１１】本発明の実施の形態５における応力センサー
の平面図である。FIG. 11 is a plan view of a stress sensor according to a fifth embodiment of the present invention.
【図１２】本発明の実施の形態５における磁気抵抗効果
素子の応力と抵抗変化率の関係を示す図である。FIG. 12 is a diagram showing a relationship between a stress and a rate of change in resistance of a magnetoresistive element according to a fifth embodiment of the present invention.
【図１３】従来の応力センサーの平面図である。FIG. 13 is a plan view of a conventional stress sensor.
１、４１、６１、９１、１１１ 磁気抵抗効果素子 ２、４２ 磁化固着層 ３、４３ 絶縁層 ４、４４ 磁化自由層 ５，７、４５、４７、６５，９５ 磁化 ６、４６、６２、９２ 磁化容易軸 ８、９、４８、４９、６６、６７、７６、７７、９６，
９７、１１８、１１９応力印加方向 １０、５１ 電極 ５２ 電流 ６３、９３ 層間結合磁界 ６４、９４ バイアス磁界 ８１ 永久磁石 ８２ 硬質磁性膜 ８３ 反強磁性膜1, 41, 61, 91, 111 Magnetoresistive effect element 2, 42 Fixed magnetization layer 3, 43 Insulation layer 4, 44 Free magnetization layer 5, 7, 45, 47, 65, 95 Magnetization 6, 46, 62, 92 Magnetization Easy axis 8, 9, 48, 49, 66, 67, 76, 77, 96,
97, 118, 119 stress application direction 10, 51 electrode 52 current 63, 93 interlayer coupling magnetic field 64, 94 bias magnetic field 81 permanent magnet 82 hard magnetic film 83 antiferromagnetic film
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ テーマコート゛(参考） Ｈ０１Ｌ 43/08 Ｇ０１Ｐ 15/08 Ｃ (72)発明者 岡本 匡史 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 Ｆターム(参考） 2F055 AA40 BB20 CC60 DD20 EE27 FF11 GG11 ──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. 7 Identification symbol FI Theme coat ゛ (Reference) H01L 43/08 G01P 15/08 C (72) Inventor Masafumi Okamoto 1006 Kazuma Kazuma, Kadoma, Osaka Matsushita Electric Industrial F term (reference) 2F055 AA40 BB20 CC60 DD20 EE27 FF11 GG11
Claims (7)
層と、 絶縁層と、 磁歪を有する磁化自由層とを順次積層してなる磁気抵抗
効果素子を備えた応力センサーであって、 前記磁気抵抗効果素子に応力が印加されたときに、前記
磁気抵抗効果素子の抵抗値変化から、印加された応力を
検知することを特徴とする応力センサー。1. A stress sensor comprising a magnetoresistive element in which a magnetization fixed layer having magnetization fixed in one direction, an insulating layer, and a magnetization free layer having magnetostriction are sequentially stacked, A stress sensor, wherein when a stress is applied to the magnetoresistive element, the applied stress is detected from a change in the resistance value of the magnetoresistive element.
て、 前記磁気抵抗効果素子を円形状にパターニングしたこと
を特徴とする応力センサー。2. The stress sensor according to claim 1, wherein the magnetoresistive element is patterned in a circular shape.
に記載の応力センサーにおいて、 前記磁気抵抗効果素子は、前記磁化自由層上に、さらに
絶縁層と磁化固着層とを順次積層してなることを特徴と
する応力センサー。3. The stress sensor according to claim 1, wherein the magnetoresistive element is formed by sequentially laminating an insulating layer and a magnetization fixed layer on the magnetization free layer. A stress sensor characterized in that:
載の応力センサーにおいて、 応力が印加されることにより、前記磁化固着層と前記磁
化自由層との間に、層間結合磁界が発生した場合、 磁化固着層の磁化方向と、磁化自由層の磁化容易軸方向
とを略直交させ、 前記層間結合磁界を打ち消すように、バイアス磁界を印
加することを特徴とする応力センサー。4. The stress sensor according to claim 1, wherein an interlayer coupling magnetic field is generated between the magnetization fixed layer and the magnetization free layer by applying a stress. In this case, the magnetization direction of the magnetization fixed layer and the direction of the easy axis of magnetization of the magnetization free layer are substantially orthogonal to each other, and a bias magnetic field is applied so as to cancel the interlayer coupling magnetic field.
載の応力センサーにおいて、 磁化自由層に対し、磁化容易軸方向にバイアス磁界を印
加するとともに、 磁化自由層の磁化容易軸と磁化固着層の磁化方向との角
度αと、前記バイアス磁界とが、 Ｈk×cosα×sinα＋Ｈbias×cosα＋Ｈint＝０ かつ −Hk×cos(2α)＋Hbias×sinα＞０ Ｈk：磁化自由層の異方性磁界 Ｈint：磁化固着層と磁化自由層との層間結合磁界 Hbias：磁化自由層に対し、磁化容易軸方向に印加する
バイアス磁界を略満たすことを特徴とする応力センサ
ー。5. The stress sensor according to claim 1, wherein a bias magnetic field is applied to the magnetization free layer in an easy axis direction, and the magnetization axis is fixed to the easy axis of the magnetization free layer. The angle α with the magnetization direction of the layer and the bias magnetic field are: Hk × cosα × sinα + Hbias × cosα + Hint = 0 and −Hk × cos (2α) + Hbias × sinα> 0 Hbias: A stress sensor characterized by substantially satisfying a bias magnetic field applied to the magnetization free layer in the direction of the easy axis of magnetization with respect to the magnetization free layer.
載の応力センサーにおいて、 前記応力の印加方向が、磁化固着層の磁化方向に対し、
＋４５゜あるいは−４５゜であることを特徴とする応力
センサー。6. The stress sensor according to claim 1, wherein a direction in which the stress is applied is different from a magnetization direction of the magnetization fixed layer.
A stress sensor characterized by being at + 45 ° or −45 °.
載の応力センサーにおいて、 前記応力の印加方向が、無応力時の磁化自由層の磁化方
向に対し、＋４５゜あるいは−４５゜であることを特徴
とする応力センサー。7. The stress sensor according to claim 1, wherein a direction in which the stress is applied is + 45 ° or −45 ° with respect to a magnetization direction of the magnetization free layer when no stress is applied. A stress sensor characterized in that:
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Cited By (87)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010021361A1 (en) * | 2008-08-22 | 2010-02-25 | キヤノンアネルバ株式会社 | Negative resistance element using magnetoresistive effect |
| JP2011103336A (en) * | 2009-11-10 | 2011-05-26 | Denso Corp | Magnetoresistive element and sensor using the same |
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| US8755222B2 (en) | 2003-08-19 | 2014-06-17 | New York University | Bipolar spin-transfer switching |
| US8760915B2 (en) | 2003-08-19 | 2014-06-24 | New York University | High speed low power magnetic devices based on current induced spin-momentum transfer |
| JP5532166B1 (en) * | 2013-03-29 | 2014-06-25 | Ｔｄｋ株式会社 | Magnetic sensor and magnetic sensor system |
| KR101494396B1 (en) | 2012-12-07 | 2015-02-23 | 주식회사 아이엔지아이에스 | A Magnetic Applied Management System |
| US8982613B2 (en) | 2013-06-17 | 2015-03-17 | New York University | Scalable orthogonal spin transfer magnetic random access memory devices with reduced write error rates |
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| US9082950B2 (en) | 2012-10-17 | 2015-07-14 | New York University | Increased magnetoresistance in an inverted orthogonal spin transfer layer stack |
| US9263667B1 (en) | 2014-07-25 | 2016-02-16 | Spin Transfer Technologies, Inc. | Method for manufacturing MTJ memory device |
| US9337412B2 (en) | 2014-09-22 | 2016-05-10 | Spin Transfer Technologies, Inc. | Magnetic tunnel junction structure for MRAM device |
| US9728712B2 (en) | 2015-04-21 | 2017-08-08 | Spin Transfer Technologies, Inc. | Spin transfer torque structure for MRAM devices having a spin current injection capping layer |
| US9741926B1 (en) | 2016-01-28 | 2017-08-22 | Spin Transfer Technologies, Inc. | Memory cell having magnetic tunnel junction and thermal stability enhancement layer |
| US9773974B2 (en) | 2015-07-30 | 2017-09-26 | Spin Transfer Technologies, Inc. | Polishing stop layer(s) for processing arrays of semiconductor elements |
| US9812184B2 (en) | 2007-10-31 | 2017-11-07 | New York University | Current induced spin-momentum transfer stack with dual insulating layers |
| US9853206B2 (en) | 2015-06-16 | 2017-12-26 | Spin Transfer Technologies, Inc. | Precessional spin current structure for MRAM |
| JP2018006769A (en) * | 2017-09-14 | 2018-01-11 | 株式会社東芝 | Sensor, microphone, blood pressure sensor, and touch panel |
| US10032978B1 (en) | 2017-06-27 | 2018-07-24 | Spin Transfer Technologies, Inc. | MRAM with reduced stray magnetic fields |
| US10141499B1 (en) | 2017-12-30 | 2018-11-27 | Spin Transfer Technologies, Inc. | Perpendicular magnetic tunnel junction device with offset precessional spin current layer |
| JP2018201023A (en) * | 2018-07-10 | 2018-12-20 | 株式会社東芝 | Sensor, microphone, blood pressure sensor, and touch panel |
| US10163479B2 (en) | 2015-08-14 | 2018-12-25 | Spin Transfer Technologies, Inc. | Method and apparatus for bipolar memory write-verify |
| US10199083B1 (en) | 2017-12-29 | 2019-02-05 | Spin Transfer Technologies, Inc. | Three-terminal MRAM with ac write-assist for low read disturb |
| US10229724B1 (en) | 2017-12-30 | 2019-03-12 | Spin Memory, Inc. | Microwave write-assist in series-interconnected orthogonal STT-MRAM devices |
| US10236047B1 (en) | 2017-12-29 | 2019-03-19 | Spin Memory, Inc. | Shared oscillator (STNO) for MRAM array write-assist in orthogonal STT-MRAM |
| US10236048B1 (en) | 2017-12-29 | 2019-03-19 | Spin Memory, Inc. | AC current write-assist in orthogonal STT-MRAM |
| US10236439B1 (en) | 2017-12-30 | 2019-03-19 | Spin Memory, Inc. | Switching and stability control for perpendicular magnetic tunnel junction device |
| US10255962B1 (en) | 2017-12-30 | 2019-04-09 | Spin Memory, Inc. | Microwave write-assist in orthogonal STT-MRAM |
| US10270027B1 (en) | 2017-12-29 | 2019-04-23 | Spin Memory, Inc. | Self-generating AC current assist in orthogonal STT-MRAM |
| US10319900B1 (en) | 2017-12-30 | 2019-06-11 | Spin Memory, Inc. | Perpendicular magnetic tunnel junction device with precessional spin current layer having a modulated moment density |
| US10339993B1 (en) | 2017-12-30 | 2019-07-02 | Spin Memory, Inc. | Perpendicular magnetic tunnel junction device with skyrmionic assist layers for free layer switching |
| US10360964B2 (en) | 2016-09-27 | 2019-07-23 | Spin Memory, Inc. | Method of writing contents in memory during a power up sequence using a dynamic redundancy register in a memory device |
| US10360961B1 (en) | 2017-12-29 | 2019-07-23 | Spin Memory, Inc. | AC current pre-charge write-assist in orthogonal STT-MRAM |
| US10366774B2 (en) | 2016-09-27 | 2019-07-30 | Spin Memory, Inc. | Device with dynamic redundancy registers |
| US10367139B2 (en) | 2017-12-29 | 2019-07-30 | Spin Memory, Inc. | Methods of manufacturing magnetic tunnel junction devices |
| US10388861B1 (en) | 2018-03-08 | 2019-08-20 | Spin Memory, Inc. | Magnetic tunnel junction wafer adaptor used in magnetic annealing furnace and method of using the same |
| US10395712B2 (en) | 2017-12-28 | 2019-08-27 | Spin Memory, Inc. | Memory array with horizontal source line and sacrificial bitline per virtual source |
| US10411185B1 (en) | 2018-05-30 | 2019-09-10 | Spin Memory, Inc. | Process for creating a high density magnetic tunnel junction array test platform |
| US10424723B2 (en) | 2017-12-29 | 2019-09-24 | Spin Memory, Inc. | Magnetic tunnel junction devices including an optimization layer |
| US10424726B2 (en) | 2017-12-28 | 2019-09-24 | Spin Memory, Inc. | Process for improving photoresist pillar adhesion during MRAM fabrication |
| US10437491B2 (en) | 2016-09-27 | 2019-10-08 | Spin Memory, Inc. | Method of processing incomplete memory operations in a memory device during a power up sequence and a power down sequence using a dynamic redundancy register |
| US10437723B2 (en) | 2016-09-27 | 2019-10-08 | Spin Memory, Inc. | Method of flushing the contents of a dynamic redundancy register to a secure storage area during a power down in a memory device |
| US10438995B2 (en) | 2018-01-08 | 2019-10-08 | Spin Memory, Inc. | Devices including magnetic tunnel junctions integrated with selectors |
| US10438996B2 (en) | 2018-01-08 | 2019-10-08 | Spin Memory, Inc. | Methods of fabricating magnetic tunnel junctions integrated with selectors |
| US10446744B2 (en) | 2018-03-08 | 2019-10-15 | Spin Memory, Inc. | Magnetic tunnel junction wafer adaptor used in magnetic annealing furnace and method of using the same |
| US10446210B2 (en) | 2016-09-27 | 2019-10-15 | Spin Memory, Inc. | Memory instruction pipeline with a pre-read stage for a write operation for reducing power consumption in a memory device that uses dynamic redundancy registers |
| US10460781B2 (en) | 2016-09-27 | 2019-10-29 | Spin Memory, Inc. | Memory device with a dual Y-multiplexer structure for performing two simultaneous operations on the same row of a memory bank |
| US10468588B2 (en) | 2018-01-05 | 2019-11-05 | Spin Memory, Inc. | Perpendicular magnetic tunnel junction device with skyrmionic enhancement layers for the precessional spin current magnetic layer |
| US10468590B2 (en) | 2015-04-21 | 2019-11-05 | Spin Memory, Inc. | High annealing temperature perpendicular magnetic anisotropy structure for magnetic random access memory |
| US10481976B2 (en) | 2017-10-24 | 2019-11-19 | Spin Memory, Inc. | Forcing bits as bad to widen the window between the distributions of acceptable high and low resistive bits thereby lowering the margin and increasing the speed of the sense amplifiers |
| US10489245B2 (en) | 2017-10-24 | 2019-11-26 | Spin Memory, Inc. | Forcing stuck bits, waterfall bits, shunt bits and low TMR bits to short during testing and using on-the-fly bit failure detection and bit redundancy remapping techniques to correct them |
| US10529915B2 (en) | 2018-03-23 | 2020-01-07 | Spin Memory, Inc. | Bit line structures for three-dimensional arrays with magnetic tunnel junction devices including an annular free magnetic layer and a planar reference magnetic layer |
| US10529439B2 (en) | 2017-10-24 | 2020-01-07 | Spin Memory, Inc. | On-the-fly bit failure detection and bit redundancy remapping techniques to correct for fixed bit defects |
| US10546625B2 (en) | 2016-09-27 | 2020-01-28 | Spin Memory, Inc. | Method of optimizing write voltage based on error buffer occupancy |
| US10546624B2 (en) | 2017-12-29 | 2020-01-28 | Spin Memory, Inc. | Multi-port random access memory |
| US10559338B2 (en) | 2018-07-06 | 2020-02-11 | Spin Memory, Inc. | Multi-bit cell read-out techniques |
| US10580827B1 (en) | 2018-11-16 | 2020-03-03 | Spin Memory, Inc. | Adjustable stabilizer/polarizer method for MRAM with enhanced stability and efficient switching |
| US10593396B2 (en) | 2018-07-06 | 2020-03-17 | Spin Memory, Inc. | Multi-bit cell read-out techniques for MRAM cells with mixed pinned magnetization orientations |
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| US10628316B2 (en) | 2016-09-27 | 2020-04-21 | Spin Memory, Inc. | Memory device with a plurality of memory banks where each memory bank is associated with a corresponding memory instruction pipeline and a dynamic redundancy register |
| US10656994B2 (en) | 2017-10-24 | 2020-05-19 | Spin Memory, Inc. | Over-voltage write operation of tunnel magnet-resistance (“TMR”) memory device and correcting failure bits therefrom by using on-the-fly bit failure detection and bit redundancy remapping techniques |
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| US10679685B2 (en) | 2017-12-27 | 2020-06-09 | Spin Memory, Inc. | Shared bit line array architecture for magnetoresistive memory |
| US10692569B2 (en) | 2018-07-06 | 2020-06-23 | Spin Memory, Inc. | Read-out techniques for multi-bit cells |
| US10699761B2 (en) | 2018-09-18 | 2020-06-30 | Spin Memory, Inc. | Word line decoder memory architecture |
| WO2020158159A1 (en) * | 2019-01-30 | 2020-08-06 | 株式会社村田製作所 | Stress sensor and manufacturing method for same |
| US10784439B2 (en) | 2017-12-29 | 2020-09-22 | Spin Memory, Inc. | Precessional spin current magnetic tunnel junction devices and methods of manufacture |
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| US11151042B2 (en) | 2016-09-27 | 2021-10-19 | Integrated Silicon Solution, (Cayman) Inc. | Error cache segmentation for power reduction |
| JP2023500083A (en) * | 2019-10-30 | 2023-01-04 | 江▲蘇▼多▲維▼科技有限公司 | Hydrogen gas sensor using electrically isolated tunnel magnetoresistive stress sensing element |
| US11621293B2 (en) | 2018-10-01 | 2023-04-04 | Integrated Silicon Solution, (Cayman) Inc. | Multi terminal device stack systems and methods |
| WO2023106130A1 (en) * | 2021-12-07 | 2023-06-15 | 国立大学法人大阪大学 | Distortion measurement device and distortion measurement method |
-
2001
- 2001-05-31 JP JP2001164586A patent/JP2002357489A/en active Pending
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| US10163479B2 (en) | 2015-08-14 | 2018-12-25 | Spin Transfer Technologies, Inc. | Method and apparatus for bipolar memory write-verify |
| US10643680B2 (en) | 2016-01-28 | 2020-05-05 | Spin Memory, Inc. | Memory cell having magnetic tunnel junction and thermal stability enhancement layer |
| US9741926B1 (en) | 2016-01-28 | 2017-08-22 | Spin Transfer Technologies, Inc. | Memory cell having magnetic tunnel junction and thermal stability enhancement layer |
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| US10628316B2 (en) | 2016-09-27 | 2020-04-21 | Spin Memory, Inc. | Memory device with a plurality of memory banks where each memory bank is associated with a corresponding memory instruction pipeline and a dynamic redundancy register |
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| US10446210B2 (en) | 2016-09-27 | 2019-10-15 | Spin Memory, Inc. | Memory instruction pipeline with a pre-read stage for a write operation for reducing power consumption in a memory device that uses dynamic redundancy registers |
| US11151042B2 (en) | 2016-09-27 | 2021-10-19 | Integrated Silicon Solution, (Cayman) Inc. | Error cache segmentation for power reduction |
| US10360964B2 (en) | 2016-09-27 | 2019-07-23 | Spin Memory, Inc. | Method of writing contents in memory during a power up sequence using a dynamic redundancy register in a memory device |
| US11119936B2 (en) | 2016-09-27 | 2021-09-14 | Spin Memory, Inc. | Error cache system with coarse and fine segments for power optimization |
| US10424393B2 (en) | 2016-09-27 | 2019-09-24 | Spin Memory, Inc. | Method of reading data from a memory device using multiple levels of dynamic redundancy registers |
| US10366775B2 (en) | 2016-09-27 | 2019-07-30 | Spin Memory, Inc. | Memory device using levels of dynamic redundancy registers for writing a data word that failed a write operation |
| US11119910B2 (en) | 2016-09-27 | 2021-09-14 | Spin Memory, Inc. | Heuristics for selecting subsegments for entry in and entry out operations in an error cache system with coarse and fine grain segments |
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| US11271149B2 (en) | 2017-02-28 | 2022-03-08 | Integrated Silicon Solution, (Cayman) Inc. | Precessional spin current structure with nonmagnetic insertion layer for MRAM |
| US11355699B2 (en) | 2017-02-28 | 2022-06-07 | Integrated Silicon Solution, (Cayman) Inc. | Precessional spin current structure for MRAM |
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| US10481976B2 (en) | 2017-10-24 | 2019-11-19 | Spin Memory, Inc. | Forcing bits as bad to widen the window between the distributions of acceptable high and low resistive bits thereby lowering the margin and increasing the speed of the sense amplifiers |
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| US10489245B2 (en) | 2017-10-24 | 2019-11-26 | Spin Memory, Inc. | Forcing stuck bits, waterfall bits, shunt bits and low TMR bits to short during testing and using on-the-fly bit failure detection and bit redundancy remapping techniques to correct them |
| US10679685B2 (en) | 2017-12-27 | 2020-06-09 | Spin Memory, Inc. | Shared bit line array architecture for magnetoresistive memory |
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| US10424723B2 (en) | 2017-12-29 | 2019-09-24 | Spin Memory, Inc. | Magnetic tunnel junction devices including an optimization layer |
| US10229724B1 (en) | 2017-12-30 | 2019-03-12 | Spin Memory, Inc. | Microwave write-assist in series-interconnected orthogonal STT-MRAM devices |
| US10319900B1 (en) | 2017-12-30 | 2019-06-11 | Spin Memory, Inc. | Perpendicular magnetic tunnel junction device with precessional spin current layer having a modulated moment density |
| US10236439B1 (en) | 2017-12-30 | 2019-03-19 | Spin Memory, Inc. | Switching and stability control for perpendicular magnetic tunnel junction device |
| US10141499B1 (en) | 2017-12-30 | 2018-11-27 | Spin Transfer Technologies, Inc. | Perpendicular magnetic tunnel junction device with offset precessional spin current layer |
| US10255962B1 (en) | 2017-12-30 | 2019-04-09 | Spin Memory, Inc. | Microwave write-assist in orthogonal STT-MRAM |
| US10339993B1 (en) | 2017-12-30 | 2019-07-02 | Spin Memory, Inc. | Perpendicular magnetic tunnel junction device with skyrmionic assist layers for free layer switching |
| US10468588B2 (en) | 2018-01-05 | 2019-11-05 | Spin Memory, Inc. | Perpendicular magnetic tunnel junction device with skyrmionic enhancement layers for the precessional spin current magnetic layer |
| US10438996B2 (en) | 2018-01-08 | 2019-10-08 | Spin Memory, Inc. | Methods of fabricating magnetic tunnel junctions integrated with selectors |
| US10438995B2 (en) | 2018-01-08 | 2019-10-08 | Spin Memory, Inc. | Devices including magnetic tunnel junctions integrated with selectors |
| US10446744B2 (en) | 2018-03-08 | 2019-10-15 | Spin Memory, Inc. | Magnetic tunnel junction wafer adaptor used in magnetic annealing furnace and method of using the same |
| US10388861B1 (en) | 2018-03-08 | 2019-08-20 | Spin Memory, Inc. | Magnetic tunnel junction wafer adaptor used in magnetic annealing furnace and method of using the same |
| US10529915B2 (en) | 2018-03-23 | 2020-01-07 | Spin Memory, Inc. | Bit line structures for three-dimensional arrays with magnetic tunnel junction devices including an annular free magnetic layer and a planar reference magnetic layer |
| US10411185B1 (en) | 2018-05-30 | 2019-09-10 | Spin Memory, Inc. | Process for creating a high density magnetic tunnel junction array test platform |
| US10615337B2 (en) | 2018-05-30 | 2020-04-07 | Spin Memory, Inc. | Process for creating a high density magnetic tunnel junction array test platform |
| US10600478B2 (en) | 2018-07-06 | 2020-03-24 | Spin Memory, Inc. | Multi-bit cell read-out techniques for MRAM cells with mixed pinned magnetization orientations |
| US10593396B2 (en) | 2018-07-06 | 2020-03-17 | Spin Memory, Inc. | Multi-bit cell read-out techniques for MRAM cells with mixed pinned magnetization orientations |
| US10692569B2 (en) | 2018-07-06 | 2020-06-23 | Spin Memory, Inc. | Read-out techniques for multi-bit cells |
| US10559338B2 (en) | 2018-07-06 | 2020-02-11 | Spin Memory, Inc. | Multi-bit cell read-out techniques |
| JP2018201023A (en) * | 2018-07-10 | 2018-12-20 | 株式会社東芝 | Sensor, microphone, blood pressure sensor, and touch panel |
| US10699761B2 (en) | 2018-09-18 | 2020-06-30 | Spin Memory, Inc. | Word line decoder memory architecture |
| US10971680B2 (en) | 2018-10-01 | 2021-04-06 | Spin Memory, Inc. | Multi terminal device stack formation methods |
| US11621293B2 (en) | 2018-10-01 | 2023-04-04 | Integrated Silicon Solution, (Cayman) Inc. | Multi terminal device stack systems and methods |
| US10580827B1 (en) | 2018-11-16 | 2020-03-03 | Spin Memory, Inc. | Adjustable stabilizer/polarizer method for MRAM with enhanced stability and efficient switching |
| US11107979B2 (en) | 2018-12-28 | 2021-08-31 | Spin Memory, Inc. | Patterned silicide structures and methods of manufacture |
| JP7031023B2 (en) | 2019-01-30 | 2022-03-07 | 株式会社村田製作所 | Stress sensor and its manufacturing method |
| JPWO2020158159A1 (en) * | 2019-01-30 | 2021-11-25 | 株式会社村田製作所 | Stress sensor and its manufacturing method |
| WO2020158159A1 (en) * | 2019-01-30 | 2020-08-06 | 株式会社村田製作所 | Stress sensor and manufacturing method for same |
| US11959815B2 (en) | 2019-01-30 | 2024-04-16 | Murata Manufacturing Co., Ltd. | Stress sensor and manufacturing method therefor |
| JP2023500083A (en) * | 2019-10-30 | 2023-01-04 | 江▲蘇▼多▲維▼科技有限公司 | Hydrogen gas sensor using electrically isolated tunnel magnetoresistive stress sensing element |
| WO2023106130A1 (en) * | 2021-12-07 | 2023-06-15 | 国立大学法人大阪大学 | Distortion measurement device and distortion measurement method |
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