Method for manufacturing wafers and magnetic sensors

Abstract

This invention provides a wafer in which the magnetization direction of the magnetization fixed layer can be efficiently fixed. [Solution] The wafer 100 comprises a plurality of MR elements 50, a plurality of arrays 105, and a plurality of dies 104. Each of the plurality of MR elements 50 includes a magnetization fixed layer 52. The magnetization direction of the magnetization fixed layer 52 is defined for each array 105. The plurality of dies 104 are arranged at a first pitch P1. The arrays 105 are arranged at a second pitch P2. The MR elements 50 are arranged at a third pitch P3. The dies 104 and the arrays 105 are arranged such that the second pitch P2 is not greater than the first pitch P1. The arrays 105 and the MR elements 50 are arranged such that the third pitch P3 is not greater than the second pitch P2.

Description

Technical Field

[0001] The present disclosure relates to a wafer used in the manufacture of a magnetic sensor and a method for manufacturing a magnetic sensor.

Background Art

[0002] In recent years, magnetic sensors have been used in various applications. As a magnetic sensor, one using a spin valve type magnetoresistive effect element provided on a substrate is known. The spin valve type magnetoresistive effect element includes a magnetization fixed layer with a fixed magnetization direction, a free layer whose magnetization direction can change according to a magnetic field, and a gap layer disposed between the magnetization fixed layer and the free layer.

[0003] Further, the magnetic sensor includes a bridge circuit configured to detect a magnetic field to be detected and generate a detection signal. In a magnetic sensor using a spin valve type magnetoresistive effect element, the bridge circuit is configured using a plurality of types of magnetoresistive effect elements whose magnetization directions of the magnetization fixed layers are fixed in different directions from each other.

[0004] Patent Document 1 and Patent Document 2 disclose a magnetic sensor configured using a plurality of types of magnetoresistive effect elements whose magnetization directions of the ferromagnetic reference layers are fixed in different directions from each other, and a method for manufacturing this magnetic sensor. In Patent Document 1 and Patent Document 2, for the manufacture of a magnetic sensor, a wafer in which a plurality of types of magnetoresistive effect elements are formed in different areas is used. The magnetization direction of each ferromagnetic reference layer of the plurality of types of magnetoresistive effect elements is directly determined using a laser beam and an electromagnet.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

[0006] To reduce the manufacturing cost of magnetic sensors, shortening the lead time is crucial. In particular, for magnetic sensors containing multiple types of magnetoresistive elements whose magnetization directions in the magnetization base layer are fixed in different directions, it is necessary to devise methods to efficiently fix the magnetization direction of the magnetization base layer during the manufacturing process. However, such methods have not been sufficiently considered in the past.

[0007] This disclosure has been made in view of the aforementioned problems, and its purpose is to provide a wafer capable of efficiently fixing the direction of magnetization of a magnetization fixed layer, and a method for manufacturing a magnetic sensor using this wafer. [Means for solving the problem]

[0008] The wafer of this disclosure is used for manufacturing a plurality of magnetic sensors. The wafer of this disclosure comprises a plurality of regularly arranged magnetoresistive elements, a plurality of regularly arranged arrays, each containing some of the plurality of magnetoresistive elements, and a plurality of dies, each regularly partitioned to correspond to a plurality of magnetic sensors and containing some of the arrays. Each of the plurality of magnetoresistive elements includes a magnetization-fixed layer with a fixed magnetization direction, a free layer whose magnetization direction can be changed in response to an applied magnetic field, and a gap layer disposed between the magnetization-fixed layer and the free layer. The magnetization direction of the magnetization-fixed layer is defined for each of the plurality of arrays. The plurality of dies are arranged at a first pitch. Some arrays are arranged at a second pitch in each of the plurality of dies and are electrically connected to form a bridge circuit. Some magnetoresistive elements are arranged at a third pitch in each of the plurality of arrays and are electrically connected. The plurality of dies and some arrays are arranged such that the second pitch is not greater than the first pitch. Some arrays and some magnetoresistive elements are arranged such that the third pitch is not larger than the second pitch.

[0009] The present disclosure is a method for manufacturing a magnetic sensor using a wafer. The wafer comprises a plurality of regularly arranged magnetoresistive elements, a plurality of regularly arranged arrays each containing some of the plurality of magnetoresistive elements, and a plurality of dies regularly partitioned to correspond to a plurality of magnetic sensors and containing some of the arrays. Each of the plurality of magnetoresistive elements includes a magnetization-fixed layer with a fixed magnetization direction, a free layer whose magnetization direction can be changed according to an applied magnetic field, and a gap layer disposed between the magnetization-fixed layer and the free layer. The magnetization direction of the magnetization-fixed layer is defined for each of the plurality of arrays. The plurality of dies are arranged at a first pitch. Some arrays are arranged at a second pitch in each of the plurality of dies and are electrically connected to form a bridge circuit. Some magnetoresistive elements are arranged at a third pitch in each of the plurality of arrays and are electrically connected. The plurality of dies and some arrays are arranged such that the second pitch is not greater than the first pitch. Some arrays and some magnetoresistive elements are arranged such that the third pitch is not larger than the second pitch.

[0010] The method for manufacturing a magnetic sensor according to this disclosure comprises the steps of manufacturing a wafer, manufacturing multiple chips by separating multiple dies from the wafer, and manufacturing multiple magnetic sensors from the multiple chips. The wafer manufacturing step includes an element formation step of forming multiple magnetoresistive elements and multiple arrays, and a step of forming wiring for connecting the multiple magnetoresistive elements. The element formation step includes a step of forming multiple initial magnetoresistive elements, each including an initial magnetization fixed layer and a free layer, which will later become a magnetization fixed layer, and a fixing step of fixing the magnetization direction of each initial magnetization fixed layer of the multiple initial magnetoresistive elements. [Effects of the Invention]

[0011] In the wafer of this disclosure, multiple dies and some arrays are arranged such that the second pitch is not greater than the first pitch. Some arrays and some magnetoresistive elements are arranged such that the third pitch is not greater than the second pitch. This provides the effect that the magnetization direction of the magnetization fixed layer can be efficiently fixed according to this disclosure. [Brief explanation of the drawing]

[0012] [Figure 1] This is a circuit diagram showing the circuit configuration of a magnetic sensor in the first embodiment of the present disclosure. [Figure 2] This is a perspective view showing a portion of the magnetic sensor in the first embodiment of the present disclosure. [Figure 3] This is a flowchart showing a method for manufacturing a magnetic sensor according to the first embodiment of the present disclosure. [Figure 4] This is a flowchart showing a wafer manufacturing method according to the first embodiment of this disclosure. [Figure 5] This is a plan view showing a wafer according to the first embodiment of this disclosure. [Figure 6] This is a plan view showing a portion of a wafer according to the first embodiment of this disclosure. [Figure 7] This is a plan view showing a plurality of dies included in the irradiated region of a wafer according to the first embodiment of the present disclosure. [Figure 8] This is a plan view showing two dies of a wafer according to the first embodiment of the present disclosure. [Figure 9] This is an explanatory diagram showing the irradiated area in the first step of the fixing process in the first embodiment of the present disclosure. [Figure 10] This is an explanatory diagram showing the irradiated area in the second step of the fixing step in the first embodiment of the present disclosure. [Figure 11] This is an explanatory diagram showing the irradiated area in a second embodiment of the present disclosure. [Figure 12] This is an explanatory diagram showing the irradiated area in the third embodiment of the present disclosure. [Figure 13] A plan view showing one die in the fourth embodiment of the present disclosure. [Figure 14] A plan view showing one die in the fifth embodiment of the present disclosure. [Figure 15] A circuit diagram showing the circuit configuration of the magnetic sensor in the sixth embodiment of the present disclosure. [Figure 16] A plan view showing one die in the sixth embodiment of the present disclosure. [Figure 17] A circuit diagram showing the circuit configuration of the magnetic sensor in the seventh embodiment of the present disclosure. [Figure 18] A plan view showing one die in the seventh embodiment of the present disclosure.

Embodiments for Carrying Out the Invention

[0013] [First Embodiment] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. First, referring to FIGS. 1 and 2, an example of the configuration of a magnetic sensor 1 manufactured by the method for manufacturing a magnetic sensor according to the first embodiment of the present disclosure will be described. FIG. 1 is a circuit diagram showing the circuit configuration of the magnetic sensor 1. FIG. 2 is a perspective view showing a part of the magnetic sensor 1.

[0014] The magnetic sensor 1 includes a power supply port V, a ground port G, at least one output port, and at least two resistance portions. In particular, in the present embodiment, the magnetic sensor 1 includes two output ports E1 and E2 as at least one output port, and four resistance portions R1, R2, R3, and R4 as at least two resistance portions. A voltage or current of a predetermined magnitude is applied to the power supply port V. The ground port G is connected to the ground.

[0015] Resistor R1 is located between the power port V and the output port E1 in the circuit configuration. Resistor R2 is located between the ground port G and the output port E1 in the circuit configuration. Resistor R3 is located between the ground port G and the output port E2 in the circuit configuration. Resistor R4 is located between the power port V and the output port E2 in the circuit configuration. In this application, the expression "in the circuit configuration" refers to the arrangement on the circuit diagram, not the arrangement in the physical configuration.

[0016] The magnetic sensor 1 further comprises a plurality of magnetoresistive elements (hereinafter referred to as MR elements) 50. Each of the resistive sections R1 to R4 contains two or more MR elements 50, which are some of the plurality of MR elements 50.

[0017] The magnetic sensor 1 further comprises a plurality of lower electrodes 61 and a plurality of upper electrodes 62 for electrically connecting a plurality of MR elements 50. The plurality of lower electrodes 61 and the plurality of upper electrodes 62 contain a conductive material. The plurality of lower electrodes 61 are arranged on a substrate (not shown). The plurality of MR elements 50 are arranged on the plurality of lower electrodes 61. The plurality of upper electrodes 62 are arranged on the plurality of MR elements 50.

[0018] The method for connecting the multiple MR elements 50, multiple lower electrodes 61, and multiple upper electrodes 62 is as follows. As shown in Figure 2, each lower electrode 61 has an elongated shape. A gap is formed between two adjacent lower electrodes 61 in the longitudinal direction. On the upper surface of the lower electrode 61, an MR element 50 is placed near both ends in the longitudinal direction. Each upper electrode 62 also has an elongated shape and is placed on two adjacent lower electrodes 61 in the longitudinal direction to electrically connect two adjacent MR elements 50. In this way, multiple MR elements 50 are connected in series.

[0019] Here, we focus on any one of the multiple MR elements 50. The MR element 50 is a spin valve type MR element. The MR element 50 has a magnetization fixed layer 52 in which the direction of magnetization is fixed, a free layer 54 in which the direction of magnetization can be changed according to the direction and strength of the applied magnetic field, and a gap layer 53 disposed between the magnetization fixed layer 52 and the free layer 54. The MR element 50 may be a TMR (tunnel magnetoresistance) element or a GMR (giant magnetoresistance) element. In a TMR element, the gap layer 53 is a tunnel barrier layer. In a GMR element, the gap layer 53 is a non-magnetic conductive layer. In the MR element 50, the resistance value changes according to the angle that the direction of magnetization of the free layer 54 makes with respect to the direction of magnetization of the magnetization fixed layer 52. The resistance value is at its minimum when this angle is 0° and at its maximum when the angle is 180°.

[0020] The magnetized fixed layer 52 contains a magnetic material such as CoFe, CoFeB, or CoNiFe. The magnetized fixed layer 52 may further contain a non-magnetic material such as Ru. The free layer 54 contains a magnetic material such as CoFe, CoFeB, NiFe, or CoNiFe.

[0021] The MR element 50 further includes an antiferromagnetic layer 51. The antiferromagnetic layer 51, magnetization-fixed layer 52, gap layer 53, and free layer 54 are stacked in this order on the lower electrode 61. The antiferromagnetic layer 51 contains an antiferromagnetic material such as IrMn or PtMn, and creates exchange coupling with the magnetization-fixed layer 52 to fix the magnetization direction of the magnetization-fixed layer 52. The magnetization-fixed layer 52 may be a so-called self-pinned fixed layer (Synthetic Ferri Pinned layer, SFP layer). The self-pinned fixed layer has a stacked ferri structure in which a ferromagnetic layer, a non-magnetic intermediate layer, and a ferromagnetic layer are stacked, and the two ferromagnetic layers are antiferromagnetically coupled. If the magnetization-fixed layer 52 is a self-pinned fixed layer, the antiferromagnetic layer 51 may be omitted.

[0022] Note that the arrangement of layers 51 to 54 in each of the MR elements 50 may be reversed vertically from the arrangement shown in Figure 2.

[0023] Furthermore, the free layer 54 may or may not have an easy magnetization axis. The easy magnetization axis of the free layer 54 can be set by making its planar shape elongated in one direction, or by providing a magnetic field generator such as a magnet that applies a bias magnetic field.

[0024] Next, with reference to Figure 1, the direction of magnetization of the magnetization fixed layer 52 will be explained. The magnetization of each magnetization fixed layer 52 of the multiple MR elements 50 in the resistive sections R1 and R3 includes a component in the first magnetization direction. The magnetization of each magnetization fixed layer 52 of the multiple MR elements 50 in the resistive sections R2 and R4 includes a component in the second magnetization direction, which is opposite to the first magnetization direction. In Figure 1, the multiple arrows drawn overlapping the resistive sections R1 and R3 respectively represent the first magnetization direction, and the multiple arrows drawn overlapping the resistive sections R2 and R4 respectively represent the second magnetization direction.

[0025] Furthermore, if the magnetization of the magnetized fixed layer 52 includes a component in a specific magnetization direction, this component may be the main component of the magnetization of the magnetized fixed layer 52. Alternatively, the magnetization of the magnetized fixed layer 52 does not need to include a component in a direction perpendicular to the specific magnetization direction. In this embodiment, if the magnetization of the magnetized fixed layer 52 includes a component in a specific magnetization direction, the direction of the magnetization of the magnetized fixed layer 52 will be the specific magnetization direction or approximately the specific magnetization direction.

[0026] Here, as shown in Figure 1, we define the X, Y, and Z directions. The X, Y, and Z directions are orthogonal to each other. Furthermore, the direction opposite to the X direction is defined as the -X direction, the direction opposite to the Y direction is defined as the -Y direction, and the direction opposite to the Z direction is defined as the -Z direction. In this embodiment in particular, the Z direction is defined as one direction parallel to the stacking direction of layers 51 to 54, and moving from layer 51 toward layer 54.

[0027] In the example shown in Figure 1, the first magnetization direction is the X direction, and the second magnetization direction is the -X direction. Note that the first magnetization direction is not limited to the X direction, but may be the -X direction, the Y direction, or the -Y direction, or it may be a direction tilted with respect to the X and Y directions, respectively.

[0028] The magnetic sensor 1 is configured such that when at least one of the direction and intensity of the magnetic field being detected by the magnetic sensor 1 changes, the potential difference between the output ports E1 and E2 changes. The signals corresponding to the respective potentials of the output ports E1 and E2, or the signals corresponding to the potential difference between the output ports E1 and E2, have a correspondence with at least one of the direction and intensity of the magnetic field being detected.

[0029] Next, with reference to Figure 3, the manufacturing method of the magnetic sensor 1 according to this embodiment will be described. Figure 3 is a flowchart of the manufacturing method of the magnetic sensor 1 according to this embodiment. Here, the outline of the manufacturing method of the magnetic sensor 1 will be described using the case of manufacturing multiple magnetic sensors 1 as an example.

[0030] The method for manufacturing a magnetic sensor according to this embodiment comprises a step S10 for manufacturing a wafer used to manufacture multiple magnetic sensors 1, a step S20 for manufacturing multiple chips from the wafer, and a step S30 for manufacturing multiple magnetic sensors 1 from the multiple chips. In the wafer manufacturing step S10, multiple dies are formed, which are regularly partitioned to correspond to multiple magnetic sensors 1. In the chip manufacturing step S20, multiple dies are separated into individual pieces by wafer dicing to manufacture multiple chips. In the chip manufacturing step S30, multiple magnetic sensors 1 are manufactured by housing each of the multiple chips in a single package having multiple terminals.

[0031] Next, the wafer manufacturing process S10 will be described in detail. The wafer manufacturing process S10 includes an element formation process for forming a plurality of MR elements 50 and a plurality of arrays, which will be described later, and a wiring formation process for forming wiring to connect the plurality of MR elements 50. The wiring formation process includes a process for forming a plurality of lower electrodes 61, a process for forming a plurality of upper electrodes 62, a process for forming a plurality of first wirings to connect the resistors R1 to R4 to each other, and a process for forming a plurality of second wirings to connect the resistors R1 to R4 to electrode pads, which will be described later.

[0032] The following describes the wafer manufacturing process S10, focusing on one magnetic sensor 1. Figure 4 is a flowchart of the wafer manufacturing process S10. In wafer manufacturing process S10, first, process S11 is performed to form the lower structure of the magnetic sensor 1 on a bare wafer. The lower structure includes a plurality of components formed on the -Z direction side of the plurality of lower electrodes 61 of the magnetic sensor 1, and an insulating layer. The plurality of components may be, for example, a soft magnetic layer made of a soft magnetic material such as a plurality of yokes or at least one shield, a conductive layer made of a conductive material such as a coil, or passive or active elements that constitute the circuit of the magnetic sensor 1. Note that these components are not essential components of the magnetic sensor 1 and may not be provided.

[0033] Next, a step S12 is performed to form a plurality of lower electrodes 61, an element formation step S13 is performed to form a plurality of MR elements 50 and a plurality of arrays described later, and a step S14 is performed to form a plurality of upper electrodes. Each of steps S12 to S14 includes a plurality of sub-steps. The plurality of sub-steps may include a step of forming an insulating layer (not shown). In addition, the plurality of lower electrodes 61 may be completed before step S13 or after step S13. In the latter case, some of the sub-steps of step S12 may be performed during or after step S13.

[0034] In the element formation process S13, first, a plurality of initial MR elements, which will later become a plurality of MR elements 50, are formed. Each of the plurality of initial MR elements includes at least an initial magnetization fixed layer, which will later become a magnetization fixed layer 52, a free layer 54, and a gap layer 53. Each of the plurality of initial MR elements may further include an antiferromagnetic layer 51. The plurality of initial MR elements may be an integrated laminated film or individually patterned laminated films.

[0035] In the element formation process S13, a fixing process is then performed to fix the magnetization direction of the initial magnetization fixed layer of each of the multiple initial MR elements. In this embodiment, the fixing process specifically uses laser light and an external magnetic field to fix the magnetization direction of the initial magnetization fixed layer. The fixing process includes a first step of fixing the magnetization direction of the initial magnetization fixed layer of each of the multiple initial MR elements that will later become the multiple MR elements 50 of the resistive sections R1 and R3, and a second step of fixing the magnetization direction of the initial magnetization fixed layer of each of the multiple initial MR elements that will later become the multiple MR elements 50 of the resistive sections R2 and R4. The second step may be performed after the first step or before the first step.

[0036] In the first step, a laser beam is shone onto multiple initial MR elements while an external magnetic field is applied. If the initial MR elements include an antiferromagnetic layer 51, the laser beam is shone such that the temperature of the multiple initial MR elements shone with the laser beam is equal to or greater than the blocking temperature of the antiferromagnetic layer 51. The temperature of the multiple initial MR elements can be adjusted, for example, by the intensity or pulse width of the laser beam. After irradiation with the laser beam, when the temperature of the multiple initial MR elements falls below the blocking temperature, the magnetization direction of the initial magnetization fixed layer is fixed to the first magnetization direction (X direction).

[0037] In the first step, the direction of the external magnetic field applied to the initial magnetization fixed layer is set to a direction that allows the magnetization direction of the initial magnetization fixed layer to be fixed to a first magnetization direction. As long as the requirement of a direction that allows fixing to a first magnetization direction is met, the direction of the external magnetic field applied to the initial magnetization fixed layer may be the same as the first magnetization direction or a different direction from the first magnetization direction. In this embodiment in particular, the direction of the external magnetic field may be the same as the first magnetization direction.

[0038] Similarly, in the second step, laser light is shone onto multiple initial MR elements while applying an external magnetic field in a direction that allows the magnetization direction of the initial magnetization fixed layer to be fixed to the second magnetization direction (-X direction). As a result, the magnetization direction of the initial magnetization fixed layer is fixed to the second magnetization direction.

[0039] In the case of a multilayer film in which multiple initial MR elements are integrated, the multilayer film may be patterned so that multiple MR elements 50 of the resistive parts R1 to R4 are formed after fixing the magnetization direction of the initial magnetization fixed layer. Alternatively, in the case of a multilayer film in which multiple initial MR elements are individually patterned, fixing the magnetization direction of the initial magnetization fixed layer makes the initial magnetization fixed layer a magnetization fixed layer 52, and the multiple initial MR elements become multiple MR elements 50. Furthermore, the formation of multiple MR elements 50 results in the formation of multiple arrays.

[0040] In wafer fabrication step S10, step S15 is performed to form the upper structure of the magnetic sensor 1. The upper structure includes a plurality of components formed on the Z-direction side of the plurality of upper electrodes 62 of the magnetic sensor 1, and an insulating layer. The plurality of components may be, for example, a soft magnetic layer made of a soft magnetic material such as a plurality of yokes or at least one shield, a conductive layer made of a conductive material such as a coil, or passive or active elements that constitute the circuit of the magnetic sensor 1. Note that these components are not essential components of the magnetic sensor 1 and may not be provided.

[0041] Next, the process of forming multiple first wirings and multiple second wirings is carried out. These processes include multiple sub-processes. Some of the sub-processes may be carried out simultaneously with process S12 or process S14. Next, process S16 is carried out to form multiple electrode pads. Each of the multiple electrode pads includes four electrode pads corresponding to the power port V, ground port G, and output ports E1 and E2. The wafer is completed when the multiple electrode pads are formed.

[0042] Next, the wafer according to this embodiment will be described in detail with reference to Figures 5 to 8. Figure 5 is a plan view showing the wafer according to this embodiment. Figure 6 is a plan view showing a section of the wafer according to this embodiment. Figure 7 is a plan view showing multiple dies included in the irradiated area of ​​the wafer according to this embodiment. Figure 8 is a plan view showing two dies of the wafer according to this embodiment.

[0043] The wafer 100 according to this embodiment comprises a plurality of regularly arranged MR elements 50, a plurality of regularly arranged arrays 105 each containing some of the plurality of MR elements 50, and a plurality of dies 104 each regularly partitioned to correspond to a plurality of magnetic sensors 1 and containing some of the arrays 105. Here, the wafer 100 is divided into a plurality of rectangular sections 101. The arrangement of the plurality of dies 104, the plurality of arrays 105, and the plurality of MR elements 50 will be described below, focusing on one section 101.

[0044] As shown in Figure 6, the multiple dies 104 are arranged in such a way that multiple dies are aligned in each of two mutually orthogonal directions. Figure 6 shows the X, Y, and Z directions, similar to Figure 1. The two mutually orthogonal directions may or may not coincide with the X and Y directions. The following explanation will use the case where the two mutually orthogonal directions are the X and Y directions as an example.

[0045] In Figures 6 and 7, reference numeral 106 indicates the irradiated region where laser light is simultaneously irradiated onto a laminate containing multiple initial MR elements during the fixing process of the element formation process S13. The irradiated region 106 may be defined as the region to which effective laser light is irradiated onto the laminate, assuming the absence of a mask, as described later. Specifically, "effective laser light" means laser light having an intensity that can fix the magnetization direction of the initial magnetization fixing layer of the initial MR elements in a desired direction.

[0046] The area of ​​the irradiated region 106 may be larger than the area of ​​the planar shape of each of the multiple dies 104. In particular, in this embodiment, the dimension of the irradiated region 106 in the X direction may be larger than the dimension of the planar shape of each of the multiple dies 104 in the X direction, and may be more than twice this dimension. Also, the dimension of the irradiated region 106 in the Y direction may be larger than the dimension of the planar shape of each of the multiple dies 104 in the Y direction, and may be more than twice this dimension. In the example shown in Figures 6 and 7, the irradiated region 106 contains eight dies 104 arranged in a 2x4 grid. In this example, laser light is simultaneously irradiated onto multiple initial MR elements contained in the eight dies 104.

[0047] As shown in Figures 7 and 8, the arrays 105 are arranged in such a way that multiple arrays 105 are lined up in the X and Y directions. In this embodiment in particular, the area of ​​the planar shape of each of the arrays 105 is smaller than the area of ​​the planar shape of each of the dies 104. Each of the dies 104 includes, as part of the arrays 105, four arrays 105 arranged in a 2x2 configuration. The four arrays 105 are electrically connected to form a bridge circuit.

[0048] The magnetization direction of the magnetization fixed layer 52 of the MR element 50 is defined for each of the arrays 105. In this embodiment, the arrays 105 include a plurality of first arrays 105A in which the magnetization direction of the magnetization fixed layer 52 is defined to a first magnetization direction (X direction), and a plurality of second arrays 105B in which the magnetization direction of the magnetization fixed layer 52 is defined to a second magnetization direction (-X direction). The plurality of first arrays 105A and the plurality of second arrays 105B are arranged alternately in each of the plurality of dies 104 and across the plurality of dies 104.

[0049] Each of the multiple dies 104 includes two first arrays 105A and two second arrays 105B. In each of the multiple dies 104, the two first arrays 105A and the two second arrays 105B may be arranged in the same positional relationship. The two first arrays 105A constitute resistors R1 and R3. The two second arrays 105B constitute resistors R2 and R4. The two first arrays 105A and the two second arrays 105B are electrically connected to form a bridge circuit as shown in Figure 1, which is a bridge circuit composed of four resistors R1 to R4.

[0050] The element formation step S13 includes the step of forming multiple initial arrays that will later become multiple arrays 105. In the fixing step of the element formation step S13, laser light may be irradiated simultaneously to some of the multiple initial arrays. Multiple arrays 105 are completed by forming multiple MR elements 50, multiple lower electrodes 61 and multiple upper electrodes 62.

[0051] In Figures 7 and 8, multiple circles represent multiple MR elements 50. Note that, for convenience, the multiple MR elements 50 are depicted larger than they actually are in Figures 7 and 8. The multiple MR elements 50 are arranged so that multiple elements are lined up in both the X and Y directions. When m and n are integers greater than 1, each of the multiple arrays 105 contains multiple MR elements 50 arranged in m rows and n columns as part of the MR elements 50. In the example shown in Figures 7 and 8, each of the multiple arrays 105 contains 16 MR elements 50 arranged in 4 rows and 4 columns. In each of the multiple arrays 105, the 16 MR elements 50 are electrically connected so that one of the resistors R1 to R4 is formed.

[0052] Although not shown in the diagram, each of the multiple dies 104 further includes multiple electrode pads.

[0053] In Figure 8, the arrows labeled P1 schematically indicate the magnitude of the first pitch, which is the arrangement pitch (arrangement interval) of the multiple dies 104. The first pitch P1 may be, for example, the distance between the centroids of the planar shapes of two adjacent dies 104.

[0054] In Figure 8, the arrangement pitch of two adjacent dies 104 in the X direction is shown as the first pitch P1. Although not shown, the arrangement pitch of two adjacent dies 104 in the Y direction, i.e., the first pitch P1 in the Y direction, may or may not be equal to the first pitch P1 in the X direction shown in Figure 8. In the following explanation, unless otherwise specified, the first pitch P1 will be assumed to be equal in the X and Y directions.

[0055] In Figure 8, the arrows labeled P2 schematically indicate the magnitude of the second pitch, which is the arrangement pitch (arrangement interval) of the arrays 105 in each of the multiple dies 104. The second pitch P2 may be, for example, the distance between the centroids of the planar shapes of two adjacent arrays 105.

[0056] In Figure 8, the arrangement pitch of two adjacent arrays 105 in the Y direction is shown as the second pitch P2. The arrangement pitch of two adjacent arrays 105 in the X direction, i.e., the second pitch P2 in the X direction, may or may not be equal to the second pitch P2 in the Y direction shown in Figure 8. In the following explanation, unless otherwise specified, the second pitch P2 will be assumed to be equal in the X and Y directions.

[0057] Furthermore, the arrangement pitch of two adjacent arrays 105, each contained in a different die 104, may or may not be equal to the second pitch P2. In the former case, the multiple arrays 105 are arranged at equal intervals, independent of the multiple dies 104.

[0058] In Figure 8, the arrows labeled P3 schematically indicate the magnitude of the third pitch, which is the arrangement pitch (arrangement interval) of the multiple MR elements 50 in each of the multiple arrays 105. The third pitch P3 may be, for example, the distance between the centroids of the planar shapes of two adjacent MR elements 50.

[0059] In Figure 8, the arrangement pitch of two adjacent MR elements 50 in the X direction is shown as the third pitch P3. The arrangement pitch of two adjacent MR elements 50 in the Y direction, i.e., the third pitch P3 in the Y direction, may or may not be equal to the third pitch P3 in the X direction shown in Figure 8. In the following explanation, unless otherwise specified, the third pitch P3 will be assumed to be equal in the X and Y directions.

[0060] Furthermore, the arrangement pitch of two adjacent MR elements 50 contained in different arrays 105 may or may not be equal to the third pitch P3. Similarly, the arrangement pitch of two adjacent MR elements 50 contained in different dies 104 may or may not be equal to the third pitch P3.

[0061] Next, the relationship between the first pitch P1, the second pitch P2, and the third pitch P3 will be explained. In wafer 100, the multiple dies 104 and each of the multiple arrays 105 of the multiple dies 104 are arranged such that the second pitch P2 is not greater than the first pitch P1. In this embodiment in particular, the multiple dies 104 and each of the multiple arrays 105 of the multiple dies 104 are arranged such that the first pitch P1 is greater than the second pitch P2, that is, P1 > P2 is satisfied.

[0062] Furthermore, in the wafer 100, each of the multiple arrays 105 of the multiple dies 104 and each of the multiple MR elements 50 of the multiple arrays 105 are arranged such that the third pitch P3 is not greater than the second pitch P2. In particular, in this embodiment, each of the multiple arrays 105 of the multiple dies 104 and each of the multiple MR elements 50 of the multiple arrays 105 are arranged such that the second pitch P2 is greater than the third pitch P3, that is, satisfying P2 > P3.

[0063] Next, with reference to Figures 9 and 10, the irradiated regions 106 in the first and second fixing steps of the element formation process S13 will be described. Figure 9 is an explanatory diagram showing the irradiated region 106 in the first step. Figure 10 is an explanatory diagram showing the irradiated region 106 in the second step. In the fixing step, the wafer 100 is moved in a predetermined direction (for example, the X direction or the -X direction) while being irradiated with laser light. Figures 9 and 10 show two adjacent irradiated regions 106 in the X direction. Note that Figures 9 and 10 show an example where the two irradiated regions 106 do not overlap. However, depending on the pulse width of the laser light and the moving speed of the wafer 100, the two irradiated regions 106 may overlap.

[0064] Figure 9 shows multiple first initial arrays that are irradiated with laser light in the first step, among multiple initial arrays that will later become multiple arrays 105. These multiple first initial arrays will later become multiple first arrays 105A. In Figure 9, for convenience, the multiple first initial arrays are denoted as 105A. In the first step, a first mask (not shown) is used so that laser light is selectively irradiated onto the multiple first initial arrays of the multiple dies 104. The first mask has the function of blocking the laser light that is irradiated onto the multiple second initial arrays, which will be described later.

[0065] Figure 10 shows multiple second initial arrays, which are irradiated with laser light in the second step, among multiple initial arrays that will later become multiple arrays 105. These multiple second initial arrays will later become multiple second arrays 105B. In Figure 10, for convenience, the multiple second initial arrays are denoted as 105B. In the second step, a second mask (not shown) is used so that laser light is selectively irradiated onto the multiple second initial arrays of the multiple dies 104. The second mask has the function of blocking the laser light that is irradiated onto the multiple first initial arrays.

[0066] Here, as shown in Figures 9 and 10, when the wafer 100 is moved in a predetermined direction (e.g., the X direction or the -X direction) in each of the first and second steps, the pitch of two irradiated regions 106 that are adjacent to each other with the minimum distance between them and do not overlap in this predetermined direction is called the fourth pitch P4. The fourth pitch P4 may be, for example, the distance between the centroids of the two irradiated regions 106. In this embodiment, the fourth pitch P4 is greater than the first pitch P1.

[0067] Next, the operation and effects of the magnetic sensor 1 according to this embodiment will be described. In this embodiment, the multiple dies 104 and the multiple arrays 105 of each die 104 are arranged such that the second pitch P2 is not greater than the first pitch P1. In addition, the multiple arrays 105 of each die 104 and the multiple MR elements 50 of each array 105 are arranged such that the third pitch P3 is not greater than the second pitch P2. As a result, according to this embodiment, the number of initial MR elements that are simultaneously irradiated with laser light can be increased compared to the case where multiple initial MR elements are arranged in a way that does not satisfy the above requirements. In other words, according to this embodiment, the direction of magnetization of the magnetization fixing layer 52 can be efficiently fixed.

[0068] Furthermore, this embodiment provides the following advantages because the magnetization direction of the magnetization fixing layer 52 can be efficiently fixed. First, the time required for the fixing process can be shortened, thereby reducing the lead time of the magnetic sensor 1 and lowering the manufacturing cost of the magnetic sensor 1. Second, the time required for the fixing process can be shortened, which can suppress fluctuations in the environment during the fixing process, and as a result, can suppress fluctuations in the quality of the magnetic sensor 1. Third, the number of oscillations of the laser oscillator that generates the laser light can be reduced, which can extend the lifespan of the laser oscillator and other components, as well as reduce the number of times components such as lenses and mirrors need to be replaced. Fourth, the pulse repetition frequency of the laser light can be lowered, which can stabilize the laser light and suppress fluctuations in the quality of the magnetic sensor 1.

[0069] Furthermore, in this embodiment, the area of ​​the planar shape of each of the multiple dies 104 is larger than the area of ​​the planar shape of each of the multiple arrays 105, and the area of ​​the irradiated region 106 is larger than the area of ​​the planar shape of each of the multiple dies 104. As a result, according to this embodiment, it is possible to increase the number of initial MR elements that are simultaneously irradiated with laser light.

[0070] Furthermore, in this embodiment, in each of the multiple dies 104, the two first arrays 105A and the two second arrays 105B are arranged in the same positional relationship. As a result, according to this embodiment, the fixing process can be performed under the same conditions for each of the multiple dies 104, and the direction of magnetization of the magnetization fixing layer 52 can be efficiently fixed.

[0071] Furthermore, in this embodiment, by making the arrangement pitch of two adjacent arrays 105, each contained in a different die 104, equal to the second pitch P2, the fixing process can be performed under the same conditions regardless of the arrangement of the multiple arrays 105, and the direction of magnetization of the magnetization fixing layer 52 can be efficiently fixed.

[0072] [Second Embodiment] Next, a second embodiment of the present disclosure will be described with reference to Figure 11. Figure 11 is an explanatory diagram showing the irradiated area in this embodiment.

[0073] In this embodiment, during the fixing step of the element formation step S13, the relative area of ​​the irradiated region 107, which is the region where laser light is simultaneously irradiated onto the laminate containing multiple initial MR elements, is different from the relative area of ​​the irradiated region 106 in the first embodiment. That is, in this embodiment, the area of ​​the irradiated region 107 is the same as or approximately the same as the area of ​​the planar shape of each of the multiple dies 104. In particular, in this embodiment, the dimension of the irradiated region 107 in the X direction is the same as or approximately the same as the dimension of the planar shape of each of the multiple dies 104 in the X direction. Also, the dimension of the irradiated region 107 in the Y direction is the same as or approximately the same as the dimension of the planar shape of each of the multiple dies 104 in the Y direction.

[0074] The area of ​​the planar shape of each of the multiple dies 104 may be the same as or different from that of the first embodiment. Therefore, the area of ​​the irradiated area 107 may be smaller than the area of ​​the irradiated area 106, the same as the area of ​​the irradiated area 106, or larger than the area of ​​the irradiated area 106.

[0075] Furthermore, if the dimensions of the irradiated area 107 in the X direction are the same as or approximately the same as the dimensions of the planar shape of each of the multiple dies 104 in the X direction, the dimensions of the irradiated area 107 in the Y direction may be larger than the dimensions of the planar shape of each of the multiple dies 104 in the Y direction. Furthermore, if the dimensions of the irradiated area 107 in the Y direction are the same as or approximately the same as the dimensions of the planar shape of each of the multiple dies 104 in the Y direction, the dimensions of the irradiated area 107 in the X direction may be larger than the dimensions of the planar shape of each of the multiple dies 104 in the X direction.

[0076] Figure 11 shows a plurality of first initial arrays that are irradiated with laser light in the first step of the fixing process, among a plurality of initial arrays that will later become a plurality of arrays 105. The plurality of first initial arrays will later become a plurality of first arrays 105A. In Figure 11, for convenience, the plurality of first initial arrays are denoted by reference numeral 105A. In the first step, a first mask (not shown) may be used so that laser light is selectively irradiated onto two first initial arrays. The two first initial arrays may be contained in one die 104, or they may be contained in two adjacent dies 104. The first mask has the function of blocking the laser light irradiated onto the plurality of second initial arrays.

[0077] As described in the first embodiment, the plurality of second initial arrays are the initial arrays that are irradiated with laser light in the second step of the fixing process, among the plurality of initial arrays that later become the plurality of arrays 105. The plurality of second initial arrays later become the plurality of second arrays 105B. Although not shown, in the second step, a second mask (not shown) may be used so that laser light is selectively irradiated onto two second initial arrays. The two second initial arrays may be contained in one die 104, or they may be contained in two adjacent dies 104. The second mask has the function of blocking the laser light irradiated onto the plurality of first initial arrays.

[0078] Here, as in the first embodiment, when the wafer 100 is moved in a predetermined direction (e.g., the X direction or the -X direction) in each of the first and second steps, the pitch of two irradiated regions 107 that are adjacent to each other with the minimum distance between them in this predetermined direction and do not overlap is called the fourth pitch P4. The fourth pitch P4 may be, for example, the distance between the centroids of the two irradiated regions 107. In this embodiment, the fourth pitch P4 is equal to or approximately equal to the first pitch P1, which is the arrangement pitch (arrangement interval) of the multiple dies 104.

[0079] Other configurations, operations, and effects in this embodiment are the same as those in the first embodiment.

[0080] [Third Embodiment] Next, a third embodiment of the present disclosure will be described with reference to Figure 12. Figure 12 is an explanatory diagram showing the irradiated area in this embodiment.

[0081] In this embodiment, during the fixing step of the element formation step S13, the relative area of ​​the irradiated region 108, which is the region where laser light is simultaneously irradiated onto the laminate containing multiple initial MR elements, is different from the relative area of ​​the irradiated region 106 in the first embodiment. That is, in this embodiment, the area of ​​the irradiated region 108 is smaller than the area of ​​the planar shape of each of the multiple dies 104, and is the same as or approximately the same as the area of ​​the planar shape of each of the multiple arrays 105. In particular, in this embodiment, the dimension of the irradiated region 108 in the X direction is the same as or approximately the same as the dimension of the planar shape of each of the multiple arrays 105 in the X direction. Also, the dimension of the irradiated region 108 in the Y direction is the same as or approximately the same as the dimension of the planar shape of each of the multiple arrays 105 in the Y direction.

[0082] The area of ​​the planar shape of each of the multiple arrays 105 may be the same as or different from that of the first embodiment. Therefore, the area of ​​the irradiated area 108 may be smaller than the area of ​​the irradiated area 106, the same as the area of ​​the irradiated area 106, or larger than the area of ​​the irradiated area 106.

[0083] In this embodiment, the first step of the fixing process includes a first sub-step of fixing the magnetization direction of the initial magnetization fixed layer of each of the multiple initial MR elements in one of the two first initial arrays contained in each of the multiple dies 104, and a second sub-step of fixing the magnetization direction of the initial magnetization fixed layer of each of the multiple initial MR elements in the other of the two first initial arrays contained in each of the multiple dies 104. Figure 12 shows the irradiated region 108 in the first sub-step. In the first sub-step, laser light is selectively irradiated onto one of the first initial arrays. In the first sub-step, a mask having the function of blocking laser light irradiated onto a plurality of second initial arrays adjacent to one of the first initial arrays may be used.

[0084] Similarly, in a second sub-step, the other first initial array is selectively irradiated with laser light. In the second sub-step, a mask may be used that has the function of blocking the laser light irradiated to a plurality of second initial arrays adjacent to the other first initial array.

[0085] Furthermore, in this embodiment, the second step of the fixing process includes a third sub-step for fixing the magnetization direction of the initial magnetization fixed layer of each of the multiple initial MR elements in one of the two second initial arrays contained in each of the multiple dies 104, and a fourth sub-step for fixing the magnetization direction of the initial magnetization fixed layer of each of the multiple initial MR elements in the other of the two second initial arrays contained in each of the multiple dies 104. In the third sub-step, laser light is selectively irradiated onto one of the second initial arrays. In the third sub-step, a mask having the function of blocking laser light irradiated onto the multiple first initial arrays adjacent to one of the second initial arrays may be used.

[0086] Similarly, in the fourth sub-step, the other second initial array is selectively irradiated with laser light. In the fourth sub-step, a mask may be used that has the function of blocking the laser light irradiated to a plurality of first initial arrays adjacent to the other second initial array.

[0087] Here, as in the first embodiment, when the wafer 100 is moved in a predetermined direction (e.g., the X direction or the -X direction) in each of the first to fourth sub-processes, the pitch of two irradiated regions 108 that are adjacent to each other with the minimum distance between them in this predetermined direction and do not overlap is called the fourth pitch P4. The fourth pitch P4 may be, for example, the distance between the centroids of the two irradiated regions 108. In this embodiment, the fourth pitch P4 is equal to or approximately equal to the first pitch P1, which is the arrangement pitch (arrangement interval) of the multiple dies 104.

[0088] Other configurations, operations, and effects in this embodiment are the same as those in the first embodiment.

[0089] [Fourth Embodiment] Next, a fourth embodiment of the present disclosure will be described with reference to Figure 13. Figure 13 is a plan view showing one die 104 in this embodiment.

[0090] In this embodiment, the arrangement of the multiple MR elements 50 in each of the multiple arrays 105 differs from that of the first embodiment. In this embodiment, in each of the multiple arrays 105, the multiple MR elements 50 are arranged such that different numbers of MR elements 50 are lined up in the X direction and the Y direction, respectively. In the example shown in Figure 13, in each of the multiple arrays 105, the multiple MR elements 50 are arranged such that one MR element 50 is placed in the X direction and four MR elements 50 are lined up in the Y direction. That is, in the example shown in Figure 13, each of the multiple arrays 105 contains four MR elements 50 arranged in a 4x1 grid.

[0091] Furthermore, in this embodiment, in each of the multiple dies 104, four arrays 105 are arranged in a single row in the X direction. That is, each of the multiple dies 104 contains four arrays 105 arranged in a 1x4 grid. As in the first embodiment, the multiple first arrays 105A and the multiple second arrays 105B are arranged alternately in each of the multiple dies 104 and across the multiple dies 104.

[0092] The arrangement pitch of two adjacent arrays 105 in the X direction, i.e., the second pitch in the X direction, is smaller than the second pitch in the Y direction and is equal to the arrangement pitch of two adjacent MR elements 50 in the X direction. In this embodiment, for convenience, the arrangement pitch of two adjacent MR elements 50, each contained in a different array 105, is referred to as the third pitch in the X direction. The second pitch in the X direction is equal to the third pitch in the X direction.

[0093] In the fixing step of the element formation step S13, the area of ​​the irradiated region, which is the region where laser light is simultaneously irradiated onto the laminate containing multiple initial MR elements, may be larger than the area of ​​the planar shape of each of the multiple dies 104, as in the first embodiment. Alternatively, the area of ​​the irradiated region may be the same as or approximately the same as the area of ​​the planar shape of each of the multiple dies 104, as in the second embodiment. Alternatively, the area of ​​the irradiated region may be the same as or approximately the same as the area of ​​the planar shape of each of the multiple arrays 105, as in the third embodiment.

[0094] Other configurations, operations, and effects in this embodiment are the same as those in any of the first to third embodiments.

[0095] [Fifth Embodiment] Next, a fifth embodiment of the present disclosure will be described with reference to Figure 14. Figure 14 is a plan view showing one die 104 in this embodiment.

[0096] In this embodiment, each of the multiple dies 104 includes one array 105. The arrangement pitch of two adjacent dies 104 in the X direction is equal to or approximately equal to the arrangement pitch of two adjacent arrays 105 in the X direction. Similarly, the arrangement pitch of two adjacent dies 104 in the Y direction is equal to or approximately equal to the arrangement pitch of two adjacent arrays 105 in the Y direction.

[0097] In the fixing step of the element formation step S13, the area of ​​the irradiated region, which is the region where laser light is simultaneously irradiated onto the laminate containing multiple initial MR elements, may be larger than the area of ​​the planar shape of each of the multiple dies 104, as in the first embodiment. Alternatively, the area of ​​the irradiated region may be the same as or approximately the same as the area of ​​the planar shape of each of the multiple dies 104, as in the second embodiment. In this case, the area of ​​the irradiated region will be the same as or approximately the same as the area of ​​the planar shape of each of the multiple arrays 105, as in the third embodiment.

[0098] Other configurations, operations, and effects in this embodiment are the same as those in any of the first to third embodiments.

[0099] [Sixth Embodiment] Next, a sixth embodiment of the present disclosure will be described. First, the circuit configuration of the magnetic sensor 1 according to this embodiment will be described with reference to Figure 15. Figure 15 is a circuit diagram showing the circuit configuration of the magnetic sensor 1.

[0100] In this embodiment, resistor R1 includes two parts R1A and R1B connected in series in this order from the power port V side. Resistor R2 includes two parts R2A and R2B connected in series in this order from the output port E1 side. Resistor R3 includes two parts R3A and R3B connected in series in this order from the output port E2 side. Resistor R4 includes two parts R4A and R4B connected in series in this order from the power port V side.

[0101] Each of the subdivisions R1A, R1B, R2A, R2B, R3A, R3B, R4A, and R4B contains two or more MR elements 50, which are part of a larger group of MR elements 50.

[0102] In Figure 15, the multiple arrows drawn overlapping portions R1A, R1B, R2A, R2B, R3A, R3B, R4A, and R4B represent the magnetization direction of each magnetization fixed layer 52 of the multiple MR elements 50 in those portions. The magnetization direction of the magnetization fixed layer 52 in portion R1A and the magnetization direction of the magnetization fixed layer 52 in portion R1B form predetermined relative angles, excluding 0° and 180°.

[0103] Furthermore, the direction midway between the magnetization direction of the magnetization fixed layer 52 in section R1A and the magnetization direction of the magnetization fixed layer 52 in section R1B becomes the first magnetization direction. In this embodiment, the magnetization direction of all magnetization fixed layers 52 included in section R1A is the same. Also, the magnetization direction of all magnetization fixed layers 52 included in section R1B is the same. If the number of MR elements 50 included in section R1A is the same as the number of MR elements 50 included in section R1B, the average direction of the magnetization directions of all magnetization fixed layers 52 included in sections R1A and R1B becomes the first magnetization direction.

[0104] Similarly, the magnetization direction of the magnetization fixed layer 52 in section R3A and the magnetization direction of the magnetization fixed layer 52 in section R3B form a predetermined relative angle, excluding 0° and 180°. Furthermore, the direction midway between the magnetization direction of the magnetization fixed layer 52 in section R3A and the magnetization direction of the magnetization fixed layer 52 in section R3B becomes the first magnetization direction. In addition, the direction obtained by averaging the magnetization directions of all magnetization fixed layers 52 included in sections R3A and R3B also becomes the first magnetization direction.

[0105] In the example shown in Figure 15, the first magnetization direction is the X direction. The magnetization of the fixed magnetization layer 52 in sections R1A and R3A includes a component in the magnetization direction rotated by α° from the X direction toward the Y direction. The magnetization of the fixed magnetization layer 52 in sections R1B and R3B includes a component in the magnetization direction rotated by α° from the X direction toward the -Y direction. Note that α is greater than 0 and less than 90.

[0106] Similarly, the magnetization direction of the magnetization fixed layer 52 in section R2A and the magnetization direction of the magnetization fixed layer 52 in section R2B form a predetermined relative angle, excluding 0° and 180°. Furthermore, the direction midway between the magnetization direction of the magnetization fixed layer 52 in section R2A and the magnetization direction of the magnetization fixed layer 52 in section R2B becomes the second magnetization direction. In addition, the direction obtained by averaging the magnetization directions of all magnetization fixed layers 52 included in sections R2A and R2B becomes the second magnetization direction.

[0107] Similarly, the magnetization direction of the magnetization fixed layer 52 in section R4A and the magnetization direction of the magnetization fixed layer 52 in section R4B form a predetermined relative angle, excluding 0° and 180°. Furthermore, the direction midway between the magnetization direction of the magnetization fixed layer 52 in section R4A and the magnetization direction of the magnetization fixed layer 52 in section R4B becomes the second magnetization direction. In addition, the direction obtained by averaging the magnetization directions of all magnetization fixed layers 52 included in sections R4A and R4B becomes the second magnetization direction.

[0108] In the example shown in Figure 15, the second magnetization direction is the -X direction. The magnetization of each magnetization fixed layer 52 of the multiple MR elements 50 in sections R2A and R4A includes a component in the magnetization direction rotated by β° from the -X direction toward the Y direction. The magnetization of each magnetization fixed layer 52 of the multiple MR elements 50 in sections R2B and R4B includes a component in the magnetization direction rotated by β° from the -X direction toward the -Y direction. Note that β is greater than 0 and less than 90. β may be equal to α or different from α.

[0109] Next, with reference to Figure 16, the configuration of each of the multiple dies 104 in this embodiment will be described. Figure 16 is a plan view showing one die 104 in this embodiment. In this embodiment, each of the multiple dies 104 includes multiple arrays 105, which consist of two arrays 105A1, two arrays 105A2, two arrays 105B1, and two arrays 105B2. In the example shown in Figure 16, at the Y-direction side of the die 104, arrays 105A2, 105A1, 105B1, and 105B2 are arranged in this order in the X-direction, and at the -Y-direction side of the die 104, arrays 105B1, 105B2, 105A2, and 105A1 are arranged in this order in the X-direction.

[0110] In the two arrays 105A1, the magnetization direction of the magnetization fixed layer 52 is defined as a magnetization direction rotated by α° from the X direction to the Y direction. In the two arrays 105A2, the magnetization direction of the magnetization fixed layer 52 is defined as a magnetization direction rotated by α° from the X direction to the -Y direction. In the two arrays 105B1, the magnetization direction of the magnetization fixed layer 52 is defined as a magnetization direction rotated by β° from the -X direction to the Y direction. In the two arrays 105B2, the magnetization direction of the magnetization fixed layer 52 is defined as a magnetization direction rotated by β° from the -X direction to the -Y direction.

[0111] Note that the arrangements of arrays 105A1, 105A2, 105B1, and 105B2 are not limited to the example shown in Figure 16, but are arbitrary.

[0112] The two arrays 105A1 constitute part R1A of resistor R1 and part R3A of resistor R3. The two arrays 105A2 constitute part R1B of resistor R1 and part R3B of resistor R3. The two arrays 105B1 constitute part R2A of resistor R2 and part R4A of resistor R4. The two arrays 105B2 constitute part R2B of resistor R2 and part R4B of resistor R4.

[0113] One of the two arrays 105A1 and one of the two arrays 105A2 are electrically connected to form a resistor R1. One of the two arrays 105B1 and one of the two arrays 105B2 are electrically connected to form a resistor R2. The other of the two arrays 105A1 and the other of the two arrays 105A2 are electrically connected to form a resistor R3. The other of the two arrays 105B1 and the other of the two arrays 105B2 are electrically connected to form a resistor R4. Furthermore, arrays 105A1, 105A2, 105B1, and 105B2 are electrically connected to form the bridge circuit shown in Figure 15, which is a bridge circuit composed of four resistors R1 to R4.

[0114] Other configurations, operations, and effects in this embodiment are the same as those in the first embodiment.

[0115] [Seventh Embodiment] Next, a seventh embodiment of the present disclosure will be described. First, the circuit configuration of the magnetic sensor 2 according to this embodiment will be described with reference to Figure 17. Figure 17 is a circuit diagram showing the circuit configuration of the magnetic sensor 2.

[0116] The magnetic sensor 2 includes a first detection circuit 21, which is a bridge circuit, and a second detection circuit 22, which is also a bridge circuit. The configuration of the first detection circuit 21 is the same as that of the magnetic sensor 1 according to the first embodiment. That is, the first detection circuit 21 includes a power port V1, a ground port G1, two output ports E11 and E12, and four resistors R11, R12, R13, and R14. A predetermined voltage or current is applied to the power port V1. The ground port G1 is connected to ground.

[0117] Resistor R11 is located between the power port V1 and the output port E11 in the circuit configuration. Resistor R12 is located between the ground port G1 and the output port E11 in the circuit configuration. Resistor R13 is located between the ground port G1 and the output port E12 in the circuit configuration. Resistor R14 is located between the power port V1 and the output port E12 in the circuit configuration.

[0118] The configuration of the second detection circuit 22 is the same as that of the first detection circuit 21. That is, the second detection circuit 22 includes a power port V2, a ground port G2, two output ports E21 and E22, and four resistors R21, R22, R23, and R24. A predetermined voltage or current is applied to the power port V2. The ground port G2 is connected to ground.

[0119] Resistor R21 is located between the power port V2 and the output port E21 in the circuit configuration. Resistor R22 is located between the ground port G2 and the output port E21 in the circuit configuration. Resistor R23 is located between the ground port G2 and the output port E22 in the circuit configuration. Resistor R24 ​​is located between the power port V2 and the output port E22 in the circuit configuration.

[0120] Each of the resistors R11-R14 and R21-R24 contains two or more MR elements 50, which are some of the MR elements 50 from a group of MR elements 50.

[0121] The magnetization of each magnetization fixed layer 52 of the multiple MR elements 50 in the resistive sections R11 and R13 includes a component in the first magnetization direction. The magnetization of each magnetization fixed layer 52 of the multiple MR elements 50 in the resistive sections R12 and R14 includes a component in the second magnetization direction, which is opposite to the first magnetization direction. In Figure 17, the multiple arrows drawn overlapping the resistive sections R11 and R13 represent the first magnetization direction, and the multiple arrows drawn overlapping the resistive sections R12 and R14 represent the second magnetization direction. In the example shown in Figure 17, the first magnetization direction is the X direction, and the second magnetization direction is the -X direction.

[0122] The magnetization of each magnetization fixed layer 52 of the multiple MR elements 50 in the resistive sections R21 and R23 includes a component in a third magnetization direction. The magnetization of each magnetization fixed layer 52 of the multiple MR elements 50 in the resistive sections R22 and R24 includes a component in a fourth magnetization direction opposite to the third magnetization direction. In Figure 17, the multiple arrows drawn overlapping the resistive sections R21 and R23 represent the third magnetization direction, and the multiple arrows drawn overlapping the resistive sections R22 and R24 represent the fourth magnetization direction. In the example shown in Figure 17, the third magnetization direction is the Y direction, and the fourth magnetization direction is the -Y direction.

[0123] The magnetic sensor 2 may generate a signal corresponding to the potential difference between output ports E11 and E12 as a first detection signal, and a signal corresponding to the potential difference between output ports E21 and E22 as a second detection signal. The first detection signal may correspond to the component of the magnetic field to be detected in a direction parallel to the X direction. The second detection signal may correspond to the component of the magnetic field to be detected in a direction parallel to the Y direction.

[0124] Next, with reference to Figure 18, the configuration of each of the multiple dies 104 in this embodiment will be described. Figure 18 is a plan view showing one die 104 in this embodiment. In this embodiment, each of the multiple dies 104 includes multiple arrays 105, which consist of two arrays 105A, two arrays 105B, two arrays 105C, and two arrays 105C. In the example shown in Figure 18, at the Y-direction side of the die 104, arrays 105A, 105B, 105C, and 105D are arranged in this order in the X-direction, and at the -Y-direction side of the die 104, arrays 105B, 105A, 105D, and 105C are arranged in this order in the X-direction.

[0125] In the two arrays 105A, the magnetization direction of the magnetized fixed layer 52 is defined as the first magnetization direction (X direction). In the two arrays 105B, the magnetization direction of the magnetized fixed layer 52 is defined as the second magnetization direction (-X direction). In the two arrays 105C, the magnetization direction of the magnetized fixed layer 52 is defined as the third magnetization direction (Y direction). In the two arrays 105D, the magnetization direction of the magnetized fixed layer 52 is defined as the fourth magnetization direction (-Y direction).

[0126] Note that the arrangement of arrays 105A to 105D is not limited to the example shown in Figure 18, but is arbitrary.

[0127] The two arrays 105A constitute resistors R11 and R13. The two arrays 105B constitute resistors R12 and R14. The two arrays 105A and the second array 105B are electrically connected to constitute the first detection circuit 21 shown in Figure 17.

[0128] The two arrays 105C constitute resistors R21 and R23. The two arrays 105D constitute resistors R22 and R24. The two arrays 105C and the second array 105D are electrically connected to constitute the second detection circuit 22 shown in Figure 17.

[0129] This embodiment can be combined with any of the first to sixth embodiments. The other configurations, operations, and effects of this embodiment are the same as those of any of the first to sixth embodiments.

[0130] This disclosure is not limited to the embodiments described above, and various modifications are possible. For example, the arrangement of the multiple MR elements 50 and the arrangement of the multiple arrays 105 are arbitrary and not limited to the examples shown in each embodiment, as long as the requirements of the claims are met. In each of the multiple dies 104, the multiple arrays 105 may be arranged in a single line in the Y direction.

[0131] Furthermore, each of the multiple dies 104 may include at least one first array in which the magnetization direction of the magnetization fixed layer 52 is in the X direction, at least one second array in which the magnetization direction of the magnetization fixed layer 52 is in the -X direction, at least one third array in which the magnetization direction of the magnetization fixed layer 52 is in the Y direction, and at least one fourth array in which the magnetization direction of the magnetization fixed layer 52 is in the -Y direction.

[0132] Furthermore, multiple MR elements 50 may be arranged on an inclined surface that is tilted with respect to a reference plane (a plane parallel to the surface of the wafer). In this case, the direction of magnetization of the magnetization fixed layer 52 may be defined as a direction tilted with respect to the reference plane. In the fixing step for fixing the direction of magnetization of the initial magnetization fixed layer which will later become the magnetization fixed layer 52, an external magnetic field parallel to the reference plane may be used as the external magnetic field applied to the initial magnetization fixed layer.

[0133] As described above, the wafer of this disclosure is used for manufacturing multiple magnetic sensors. The wafer of this disclosure comprises a plurality of regularly arranged magnetoresistive elements, a plurality of regularly arranged arrays, each containing some of the plurality of magnetoresistive elements, and a plurality of dies, each regularly partitioned to correspond to a plurality of magnetic sensors and containing some of the arrays. Each of the plurality of magnetoresistive elements includes a magnetization-fixed layer with a fixed magnetization direction, a free layer whose magnetization direction can be changed in response to an applied magnetic field, and a gap layer disposed between the magnetization-fixed layer and the free layer. The magnetization direction of the magnetization-fixed layer is defined for each of the plurality of arrays. The plurality of dies are arranged at a first pitch. Some arrays are arranged at a second pitch in each of the plurality of dies and are electrically connected to form a bridge circuit. Some magnetoresistive elements are arranged at a third pitch in each of the plurality of arrays and are electrically connected. The plurality of dies and some arrays are arranged such that the second pitch is not greater than the first pitch. Some arrays and some magnetoresistive elements are arranged such that the third pitch is not larger than the second pitch.

[0134] In the wafer of this disclosure, some arrays and some magnetoresistive elements may be arranged such that the second pitch is greater than the third pitch. When m and n are integers greater than 1, some magnetoresistive elements may be arranged in an m x n row configuration in each of the arrays.

[0135] Furthermore, in the wafer of this disclosure, some arrays and some magnetoresistive elements may be arranged such that the second pitch is equal to the third pitch.

[0136] Furthermore, in the wafer of this disclosure, the multiple dies and some arrays may be arranged such that the first pitch is greater than the second pitch.

[0137] Furthermore, in the wafer of this disclosure, the multiple arrays may be arranged at equal intervals without relying on multiple dies.

[0138] Furthermore, in the wafer of this disclosure, some arrays may be arranged in the same positional relationship for each of the multiple dies.

[0139] The present disclosure is a method for manufacturing a magnetic sensor using a wafer. The wafer comprises a plurality of regularly arranged magnetoresistive elements, a plurality of regularly arranged arrays each containing some of the plurality of magnetoresistive elements, and a plurality of dies regularly partitioned to correspond to a plurality of magnetic sensors and containing some of the arrays. Each of the plurality of magnetoresistive elements includes a magnetization-fixed layer with a fixed magnetization direction, a free layer whose magnetization direction can be changed according to an applied magnetic field, and a gap layer disposed between the magnetization-fixed layer and the free layer. The magnetization direction of the magnetization-fixed layer is defined for each of the plurality of arrays. The plurality of dies are arranged at a first pitch. Some arrays are arranged at a second pitch in each of the plurality of dies and are electrically connected to form a bridge circuit. Some magnetoresistive elements are arranged at a third pitch in each of the plurality of arrays and are electrically connected. The plurality of dies and some arrays are arranged such that the second pitch is not greater than the first pitch. Some arrays and some magnetoresistive elements are arranged such that the third pitch is not larger than the second pitch.

[0140] The method for manufacturing a magnetic sensor according to this disclosure comprises the steps of manufacturing a wafer, manufacturing multiple chips by separating multiple dies from the wafer, and manufacturing multiple magnetic sensors from the multiple chips. The wafer manufacturing step includes an element formation step of forming multiple magnetoresistive elements and multiple arrays, and a step of forming wiring for connecting the multiple magnetoresistive elements. The element formation step includes a step of forming multiple initial magnetoresistive elements, each including an initial magnetization fixed layer and a free layer, which will later become a magnetization fixed layer, and a fixing step of fixing the magnetization direction of each initial magnetization fixed layer of the multiple initial magnetoresistive elements.

[0141] In the method for manufacturing a magnetic sensor according to the present disclosure, the fixing step may use a laser beam and an external magnetic field to fix the direction of magnetization of the initial magnetization fixed layer. The plurality of arrays may include a plurality of first arrays and a plurality of second arrays. The magnetization of the magnetization fixed layer in the plurality of first arrays may include a component in a first direction. The magnetization of the magnetization fixed layer in the plurality of second arrays may include a component in a second direction different from the first direction. The fixing step may include a first step of fixing the direction of magnetization of the initial magnetization fixed layer of a subset of the plurality of initial magnetoresistive elements that will later become some of the magnetoresistive elements constituting a plurality of first arrays, and a second step of fixing the direction of magnetization of the initial magnetization fixed layer of a subset of the plurality of initial magnetoresistive elements that will later become some of the magnetoresistive elements constituting a plurality of second arrays. The second step may be performed after the first step.

[0142] If the fixing step fixes the magnetization direction of the initial magnetized fixed layer using laser light and an external magnetic field, the element formation step may further include a step of forming multiple initial arrays that will later become multiple arrays. The laser light may be irradiated simultaneously on some of the multiple initial arrays. The multiple arrays may be arranged at equal intervals regardless of the number of dies. Some of the arrays may be arranged in the same positional relationship for each of the multiple dies.

[0143] When the fixing process fixes the magnetization direction of the initial magnetized fixed layer using laser light and an external magnetic field, the area of ​​the planar shape of each of the multiple arrays may be smaller than the area of ​​the planar shape of each of the multiple dies. The area of ​​the region in which laser light is simultaneously irradiated onto the laminate containing multiple initial magnetoresistive elements during the fixing process may be larger than the area of ​​the planar shape of each of the multiple dies.

[0144] When the fixing process fixes the magnetization direction of the initial magnetized fixed layer using laser light and an external magnetic field, the area of ​​the planar shape of each of the multiple arrays may be smaller than the area of ​​the planar shape of each of the multiple dies. In the fixing process, the area of ​​the region in which the laser light is simultaneously irradiated onto the laminate containing multiple initial magnetoresistive elements may be larger than the area of ​​the planar shape of each of the multiple arrays and smaller than the area of ​​the planar shape of each of the multiple dies. [Explanation of symbols]

[0145] 1...Magnetic sensor, 50...MR element, 51...Antiferromagnetic layer, 52...Magnetic fixed layer, 53...Gap layer, 54...Free layer, 61...Lower electrode, 62...Upper electrode, 100...Wafer, 101...Partition, 104...Die, 105...Array, 105A...First array, 105B...Second array, 106...Irradiated area, E1, E2...Output ports, G...Ground port, P1...First pitch, P2...Second pitch, P3...Third pitch, P4...Fourth pitch, R1~R4...Resistor section, V...Power port.

Claims

1. A wafer used in the manufacture of multiple magnetic sensors, Multiple magnetoresistive elements arranged in a regular pattern, Each of the above arrays includes some of the magnetoresistive elements and is arranged in a regular pattern, The device comprises a plurality of dies, each regularly partitioned to correspond to the plurality of magnetic sensors, and including a portion of the arrays among the plurality of arrays, Each of the plurality of magnetoresistive elements includes a magnetization-fixed layer in which the direction of magnetization is fixed, a free layer in which the direction of magnetization can be changed according to the applied magnetic field, and a gap layer disposed between the magnetization-fixed layer and the free layer. The direction of magnetization in the magnetized fixed layer is defined for each of the plurality of arrays, The plurality of dies are arranged in a first pitch, The aforementioned arrays are arranged at a second pitch in each of the plurality of dies and are electrically connected to form a bridge circuit. The aforementioned magnetoresistive elements are arranged in a third pitch in each of the multiple arrays and are electrically connected. The plurality of dies and the partial array are arranged such that the second pitch is not greater than the first pitch. A wafer characterized in that the portion of the array and the portion of the magnetoresistive elements are arranged such that the third pitch is not larger than the second pitch.

2. The wafer according to claim 1, characterized in that the portion of the array and the portion of the magnetoresistive elements are arranged such that the second pitch is greater than the third pitch.

3. The wafer according to claim 2, characterized in that, when m and n are integers greater than 1, some of the magnetoresistive elements are arranged in an m x n row in each of the plurality of arrays.

4. The wafer according to claim 1, characterized in that the portion of the array and the portion of the magnetoresistive elements are arranged such that the second pitch is equal to the third pitch.

5. The wafer according to claim 1, characterized in that the plurality of dies and the partial array are arranged such that the first pitch is greater than the second pitch.

6. The wafer according to claim 1, characterized in that the plurality of arrays are arranged at equal intervals independently of the plurality of dies.

7. The wafer according to claim 1, characterized in that the aforementioned arrays are arranged in the same positional relationship for each of the plurality of dies.

8. A manufacturing method for producing multiple magnetic sensors using a wafer, The aforementioned wafer is Multiple magnetoresistive elements arranged in a regular pattern, Each of the above arrays includes some of the magnetoresistive elements and is arranged in a regular pattern, The device comprises a plurality of dies, each regularly partitioned to correspond to the plurality of magnetic sensors, and including a portion of the arrays among the plurality of arrays, Each of the plurality of magnetoresistive elements includes a magnetization-fixed layer in which the direction of magnetization is fixed, a free layer in which the direction of magnetization can be changed according to the applied magnetic field, and a gap layer disposed between the magnetization-fixed layer and the free layer. The direction of magnetization in the magnetized fixed layer is defined for each of the plurality of arrays, The plurality of dies are arranged in a first pitch, The aforementioned arrays are arranged at a second pitch in each of the plurality of dies and are electrically connected to form a bridge circuit. The aforementioned magnetoresistive elements are arranged in a third pitch in each of the plurality of arrays and are electrically connected. The plurality of dies and the partial array are arranged such that the second pitch is not greater than the first pitch. The aforementioned partial array and the aforementioned partial magnetoresistive element are arranged such that the third pitch is not greater than the second pitch. The aforementioned manufacturing method is The process of manufacturing the wafer, A process of separating the multiple dies from the wafer to produce multiple chips, The process includes manufacturing the plurality of magnetic sensors from the plurality of chips, The process for manufacturing the wafer is as follows: A device formation step for forming the plurality of magnetoresistive elements and the plurality of arrays, The process includes forming wiring for connecting the plurality of magnetoresistive elements, The above-mentioned element formation step is, Each step involves forming a plurality of initial magnetoresistive effect elements, each including an initial magnetization fixed layer and a free layer, which will later become the magnetization fixed layer. A method for manufacturing a magnetic sensor, characterized by including a fixing step of fixing the magnetization direction of the initial magnetization fixed layer of each of the plurality of initial magnetoresistive effect elements.

9. The method for manufacturing a magnetic sensor according to claim 8, characterized in that the fixing step involves fixing the direction of magnetization of the initial magnetization fixed layer using laser light and an external magnetic field.

10. The plurality of arrays includes a plurality of first arrays and a plurality of second arrays, The magnetization of the magnetization fixed layer in the plurality of first arrays includes a component in a first direction, The magnetization of the magnetization fixed layer in the plurality of second arrays includes a component in a second direction different from the first direction. The aforementioned fixing step is, A first step of fixing the magnetization direction of the initial magnetization fixed layer of each of the plurality of initial magnetoresistive elements, which will later become some of the magnetoresistive elements that constitute the plurality of first arrays, The process includes a second step of fixing the magnetization direction of the initial magnetization fixed layer of each of the other initial magnetoresistive elements, which will later become some of the magnetoresistive elements constituting the plurality of second arrays, The method for manufacturing a magnetic sensor according to claim 9, characterized in that the second step is performed after the first step.

11. The element formation step further includes a step of forming a plurality of initial arrays that will later become the plurality of arrays, The method for manufacturing a magnetic sensor according to claim 9, characterized in that the laser light is simultaneously irradiated onto some of the multiple initial arrays.

12. The method for manufacturing a magnetic sensor according to claim 11, characterized in that the plurality of arrays are arranged at equal intervals without regard to the plurality of dies.

13. The method for manufacturing a magnetic sensor according to claim 11, characterized in that the aforementioned arrays are arranged in the same positional relationship for each of the plurality of dies.

14. The area of ​​the planar shape of each of the plurality of arrays is smaller than the area of ​​the planar shape of each of the plurality of dies. The method for manufacturing a magnetic sensor according to claim 9, characterized in that, in the fixing step, the area of ​​the region in which the laser light is simultaneously irradiated onto the laminate including the plurality of initial magnetoresistive elements is larger than the area of ​​the planar shape of each of the plurality of dies.

15. The area of ​​the planar shape of each of the plurality of arrays is smaller than the area of ​​the planar shape of each of the plurality of dies. The method for manufacturing a magnetic sensor according to claim 9, characterized in that, in the fixing step, the area of ​​the region in which the laser light is simultaneously irradiated onto the laminate including the plurality of initial magnetoresistive elements is larger than the area of ​​the planar shape of each of the plurality of arrays and smaller than the area of ​​the planar shape of each of the plurality of dies.

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