Semiconductor device capable of simultaneously changing polarity and magnitude of anomalous hall effect (AHE) signal according to input current, operating method thereof, and system

Abstract

To provide a semiconductor device capable of simultaneously changing polarity and magnitude of an anomalous hall effect (AHE) signal according to input current, an operating method thereof, and a system.SOLUTION: A semiconductor device includes a free magnetization layer including a ferromagnetic layer and a nonmagnetic metal layer including current electrodes receiving input current and Hall voltage electrodes outputting Hall voltage. The Hall voltage is generated by an anomalous Hall effect occurring in the ferromagnetic layer of the free magnetization layer due to the input current flowing in the nonmagnetic metal layer. The Hall voltage has any one of a local minimum value and a local maximum value when a value of the input current sequentially changes from a first value to a second value. Any one of the first value and the second value is greater than the other one of the first value and the second value.SELECTED DRAWING: Figure 4A

Description

[Technical Field]

[0001] The present invention relates to a semiconductor device, and more particularly to a semiconductor device that simultaneously varies the polarity and magnitude of an anomalous Hall effect (AHE) signal depending on an input current and a magnetization direction, a method for operating the same, and a semiconductor system including the same. [Background technology]

[0002] The Hall effect is a phenomenon in which, when a current flows through a conductor or semiconductor and a perpendicular magnetic field is applied from the outside, a voltage is generated perpendicular to both the direction of the current and the direction of the magnetic field. The voltage generated in this case is called the Hall voltage.

[0003] The Hall effect occurs when electric charges (mainly electrons) associated with the flow of current are biased to one side within a conductor due to the force exerted by the magnetic field. The force acting in this case is called the Lorentz force, which is generated by the interaction between the magnetic field and the current. The direction of the Lorentz force is perpendicular to both the direction of the current and the direction of the magnetic field.

[0004] The anomalous Hall effect (AHE) occurs mainly in magnetic materials. In the general Hall effect, an external magnetic field generates a Hall voltage when a current flows through a conductor or semiconductor, but the AHE is a Hall voltage generated by the self-magnetization of the magnetic material. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2020 / 111862 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in view of the above-mentioned conventional techniques, and an object of the present invention is to provide a semiconductor device that simultaneously varies the polarity and magnitude of an anomalous Hall effect (AHE) signal depending on a combination of an input current value and a magnetization direction, and depending on the value of the input current to be controlled, a method for operating the same, and a semiconductor system including the same. [Means for solving the problem]

[0007] In order to achieve the above object, one aspect of the present invention provides a semiconductor device comprising: a free magnetic layer including a ferromagnetic layer; and a non-magnetic metal layer including a current electrode for receiving an input current and a Hall voltage electrode for outputting a Hall voltage, wherein the Hall voltage is generated by an anomalous Hall effect occurring in the ferromagnetic layer of the free magnetic layer due to the input current flowing through the non-magnetic metal layer, and the value of the Hall voltage when the value of the input current sequentially changes from a first value to a second value has one of a minimum value and a maximum value, and one of the first value and the second value is greater than the other of the first value and the second value.

[0008] In order to achieve the above object, one aspect of the present invention provides a semiconductor system including a semiconductor device including a free magnetic layer including a ferromagnetic layer and a non-magnetic metal layer including a current electrode and a Hall voltage electrode; an input current control circuit that supplies an input current controlled in response to a current control signal to the current electrode; and a Hall voltage detection circuit that is connected to the Hall voltage electrode and detects a Hall voltage generated by the anomalous Hall effect that appears in the ferromagnetic layer of the free magnetic layer due to the input current flowing through the non-magnetic metal layer, wherein the value of the Hall voltage when the value of the input current sequentially changes from a first value to a second value has one of a minimum value and a maximum value, and one of the first value and the second value is greater than the other of the first value and the second value.

[0009] In one embodiment, as the value of the input current increases from the first value to a threshold current value, the Hall voltage decreases and has the minimum value at the threshold current value, and as the value of the input current increases from a value greater than the threshold current value to the second value, the Hall voltage increases. In one embodiment, as the value of the input current gradually decreases from the first value to a threshold current value, the Hall voltage gradually increases and has the maximum value at the threshold current value, and as the value of the input current gradually decreases from a value smaller than the threshold current value to the second value, the Hall voltage gradually decreases.

[0010] In order to achieve the above-mentioned object, one aspect of the present invention provides a method for operating a semiconductor device including a free magnetic layer including a ferromagnetic layer and a non-magnetic metal layer, the method comprising the steps of: supplying an input current having a first value to the non-magnetic metal layer; detecting a first Hall voltage generated by the anomalous Hall effect appearing in the ferromagnetic layer due to the input current having the first value flowing through the non-magnetic metal layer; supplying the input current having a second value to the non-magnetic metal layer; and detecting a second Hall voltage generated by the anomalous Hall effect appearing in the ferromagnetic layer due to the input current having the second value flowing through the non-magnetic metal layer. [Effects of the Invention]

[0011] According to the semiconductor device, the operating method thereof, and the semiconductor system including the same of the present invention, the polarity and magnitude of the anomalous Hall effect (AHE) signal can be simultaneously varied by a combination of the value of the input current and the magnetization direction, and the polarity and magnitude of the anomalous Hall effect signal can be simultaneously varied by the value of the input current. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a semiconductor system including a semiconductor device according to an embodiment of the present invention. [Figure 2]2 is a cross-sectional view of the semiconductor device of FIG. 1 taken along the AA direction. [Figure 3] FIG. 10 is a diagram showing a hysteresis loop of Hall resistivity with respect to changes in DC current density supplied to a conventional semiconductor device. [Figure 4A] 2 is a diagram showing a hysteresis loop of the Hall resistivity or Hall voltage whose polarity and value change simultaneously with a change in the DC current density supplied to the semiconductor device of FIG. 1. FIG. [Figure 4B] 2 is a graph showing the relationship between the input current supplied to the semiconductor device of FIG. 1 and the Hall voltage. [Figure 4C] 4 is a flowchart illustrating an operation of the semiconductor device of FIG. 1 when the magnetization direction of the semiconductor device is a first magnetization direction. [Figure 4D] 10 is a flowchart illustrating an operation of the semiconductor device of FIG. 1 when the magnetization direction of the semiconductor device is a second magnetization direction. [Figure 5] 2 is a graph showing changes in Hall resistivity or Hall voltage with respect to changes in the value of an input current supplied to the semiconductor device of FIG. 1 when the magnetization direction of the semiconductor device is a first magnetization direction. [Figure 6] 2 is a graph showing a change over time in an input current input to the semiconductor device of FIG. 1; [Figure 7] 2 is a graph showing changes in the magnetization direction of the semiconductor device of FIG. 1 and changes in the Hall resistivity or Hall voltage with respect to changes in the value of the input current supplied to the semiconductor device. [Figure 8] 4 is a graph showing changes in Hall resistivity or Hall voltage with respect to changes in the value of an input current supplied to the semiconductor device of FIG. 1 when the magnetization direction of the semiconductor device is a second magnetization direction. [Figure 9] 2 is a graph showing changes in Hall resistivity or Hall voltage with respect to changes in the value of an input current supplied to the semiconductor device of FIG. 1 when the magnetization direction of the semiconductor device is a first magnetization direction. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, specific examples of embodiments of the present invention will be described in detail with reference to the drawings.

[0014] FIG. 1 shows a semiconductor system including a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of the semiconductor device of FIG. 1 taken along the AA direction.

[0015] 1 and 2, a semiconductor system 100 includes a semiconductor device (or a memory element) 110, an input current control circuit 130, and a Hall voltage detection circuit 150. The semiconductor system 100 refers to a semiconductor integrated circuit, a system on chip (SoC), a processor, etc.

[0016] The semiconductor device 110 includes a free magnetization layer (or magnetic free layer) 115 including a ferromagnetic layer, and a non-magnetic metal layer 111 formed on the free magnetization layer 115 and including current electrodes (M1a and M1b) and Hall voltage electrodes (M2a and M2b).

[0017] For example, the ferromagnetic layer of the semiconductor device 110 includes a plurality of reduced cobalt layers 101c, but the technical concept of the present invention is not limited thereto, and the non-magnetic metal layer 111 may be formed of a metal such as gold, copper, or aluminum. Each of the plurality of reduced cobalt layers 101c is separated by a palladium layer 101d.

[0018] Referring to the cross-sectional view 110_2 of FIG. 2, the free magnetic layer 115 includes a repeating layer RP, in which at least two layers of a tantalum (Ta) layer 101a, a palladium (Pd) layer 101b, a reduced cobalt (R-Co) layer 101c, and a palladium layer 101d are stacked, a palladium (Pd) layer 101f, and a tantalum (Ta) layer 101g. Each of the cobalt and reduced cobalt is a ferromagnetic material. The tantalum (Ta) layer 101a is an example of a non-magnetic material, and the technical concept of the present invention is not limited thereto. For example, the two layers (101f and 101g) can be replaced with a tunnel insulator, such as magnesium oxide (MgO), which constitutes a tunnel barrier layer of a magnetic tunnel junction (MTJ).

[0019] For example, the thickness of the tantalum layer 101a is 4 nm, the thickness of the palladium layer 101b is 3 nm, the thickness of the reduced cobalt layer 101c is 0.4 nm, the thickness of the palladium layer 101d is 1 nm, the thickness of the palladium layer 101f is 2 nm, and the thickness of the tantalum layer 101g is 3 nm. Reference numeral 113 shows the part etched by the etching process.

[0020] The input current control circuit 130 supplies an input current (Ix), the value of which is adjusted by a current control signal (CTL), to the non-magnetic metal layer 111 through a current electrode (M1a or M1b). Here, the term "value" refers to magnitude or amplitude or level.

[0021] Hall voltage detection circuit 150 detects, via Hall voltage electrodes (M2a and M2b), a Hall voltage (Vxy) generated by the anomalous Hall effect (AHE) that appears in the ferromagnetic layer(s) of free magnetic layer 115 depending on the value of input current (Ix) flowing through nonmagnetic metal layer 111 or the value of input current (Ix) input to current electrode (M1a or M1b). For example, input current Ix input to current electrode M1a is output to current electrode M1b through at least one of the multiple layers (101a-101f).

[0022] For example, an input current Ix input to current electrode M1b is output to current electrode M1a through at least one of the plurality of layers (101a to 101f).

[0023] In one embodiment, the polarity and value of the Hall voltage (Vxy) detected by the Hall voltage detection circuit 150 is determined by the value of the input current (Ix).

[0024] Referring to Figure 1, the longitudinal resistivity (ρ xx ) is defined by the following formula 1.

[0025]

number

[0026] Here, Vx is the voltage in the x-axis direction determined by the input current (Ix), the reference width W (e.g., 5 μm) and the reference distance L (e.g., 26 μm) are the same as those defined in FIG. 1, and t is the thickness of the nonmagnetic metal layer 111.

[0027] Lateral resistivity, i.e., Hall resistivity (ρ xy ) is defined by the following formula 2.

[0028]

number

[0029] FIG. 3 is a diagram showing a hysteresis loop of the Hall resistivity with respect to changes in the DC current density supplied to a conventional semiconductor device.

[0030] Although the input current embodiment is described herein as being DC current density, it is not limited thereto, and the input current may be a pulsed current or other forms of current.

[0031] 2 and 3, the structure of the conventional semiconductor device is different from the structure of the semiconductor device 110_2 shown in FIG.

[0032] For example, as illustrated in FIG. 3, the DC current density is a first DC current density (e.g., 0.8 MA / cm 2 ) to a second DC current density (e.g., 6.9mA / cm 2 ) to the change in the magnetic field applied to the conventional semiconductor device. xy The hysteresis loop (HL) of the ferromagnetic material shows almost no change. For example, the X-axis represents the strength of the external magnetic field, and its unit is kilo-oersted (kOe). The Y-axis represents the Hall resistivity (ρ xy )

[0033] That is, even if the input current corresponding to the DC current density supplied to the conventional semiconductor device is gradually changed, the Hall resistivity (ρ xy The hysteresis loop (HL) of the

[0034] FIG. 4A is a diagram showing a hysteresis loop of the Hall resistivity or Hall voltage whose polarity and value change simultaneously with a change in the DC current density supplied to the semiconductor device of FIG.

[0035] Referring to FIG. 4A, the semiconductor device 110 exhibits different hysteresis loops (HL1 to HL6) depending on the values ​​(I1 to I6) of the input current (Ix). For example, the X-axis represents the strength of the external magnetic field, and its unit is kilo-oersted (kOe). The Y-axis represents the Hall resistivity (ρ xy ) or Hall voltage (Vxy).

[0036] Referring to Figure 4A, the hysteresis loops (HL1 to HL6) change as the current Ix or voltage changes as a function of the external magnetic field. According to Figure 4A, in the region where the external magnetic field is close to zero or within the range of coercive force, the maximum and minimum values ​​of the hysteresis loops (HL1) to (HL6) vary with changes in the current Ix or voltage.

[0037] However, in typical ferromagnetic materials, when the external magnetic field is zero or within the range of the coercive field, the maximum and minimum values ​​do not change with the amplitude or magnitude of the current or voltage. In fact, referring to Figure 3, the value of the anomalous Hall effect (AHE) does not change in the region where the external magnetic field is close to zero.

[0038] Referring to FIGS. 1, 2, and 4A, a first DC current density (e.g., 0.87 MA / cm 2 When a first current value (I1) corresponding to the value (ρ) is supplied to the non-magnetic metal layer 111 through the current electrode (M1a), and the magnetic field increases from negative to positive, the Hall resistivity (ρ) according to the first current value (I1) xy ) changes from positive to negative. HL1 is the Hall resistivity (ρ xy ) is the first hysteresis loop for

[0039] Second DC current density (e.g., 3.5mA / cm 2 When the magnetic field increases from negative to positive while a second current value (I2) corresponding to the second current value (I2) is supplied to the non-magnetic metal layer 111 through the current electrode (M1a), the Hall resistivity (ρ xy) changes from positive to negative. HL2 is the Hall resistivity (ρ xy ) is the second hysteresis loop for

[0040] However, if a third DC current density (e.g., 4.4 MA / cm) is applied that is greater than the first threshold current value (IHT1), 2 When the magnetic field increases from negative to positive while a third current value (I3) corresponding to the third current value (I3) is supplied to the non-magnetic metal layer 111 through the current electrode (M1a), the Hall resistivity (ρ xy ) changes from negative to positive. HL3 is the Hall resistivity (ρ xy ) is the third hysteresis loop for

[0041] 4. DC current density (e.g., 7.0mA / cm 2 When a fourth current value (I4) corresponding to the fourth current value (I4) is supplied to the non-magnetic metal layer 111 through the current electrode (M1a), and the magnetic field increases from negative to positive, the Hall resistivity (ρ xy ) changes from negative to positive. HL4 is the Hall resistivity (ρ xy ) is the fourth hysteresis loop for

[0042] 5. DC current density (e.g., 7.8mA / cm 2 When a fifth current value (I5) corresponding to the value (ρ) is supplied to the non-magnetic metal layer 111 through the current electrode (M1a), the magnetic field increases from negative to positive. xy ) changes from negative to positive. HL5 is the Hall resistivity (ρ xy ) is the fifth hysteresis loop for

[0043] 6. DC current density (e.g., 10.0mA / cm 2 When the magnetic field increases from negative to positive while a sixth current value (I6) corresponding to the sixth current value (I6) is supplied to the non-magnetic metal layer 111 through the current electrode (M1a), the Hall resistivity (ρ xy) changes from negative to positive. HL6 is the sixth hysteresis loop with respect to the hall resistivity (ρ xy ) Here, the values of each current density (0.87 MA / cm 2 , 3.5 MA / cm 2 , 4.4 MA / cm 2 , 7.0 MA / cm 2 , 7.8 MA / cm 2 , and 10.0 MA / cm 2 ) are exemplified for the sake of convenience of explanation.

[0044] FIG. 4B is a graph showing the relationship between the input current supplied to the semiconductor device of FIG. 1 and the hall voltage.

[0045] Referring to FIGS. 4A and 4B, when there is no external magnetic field or the external magnetic field is near zero, as the value of the input current (Ix) corresponding to the DC current density supplied to the semiconductor device 110 sequentially increases from zero to the same as the first threshold current value (IHT1), the maximum value of the hall resistivity (ρ xy ) of the hysteresis loop (e.g., HL1 and HL2) decreases. As the value of the input current (Ix) corresponding to the DC current density supplied to the semiconductor device 110 sequentially increases from a value greater than the first threshold current value (ITH1) to the sixth current value (I6), the maximum value of the hall resistivity (ρ xy [[ID=​​​​​​​​​​​​​​​, 7.8MA / cm 2 , and 10.0 MA / cm 2 is.

[0048] It is assumed that the magnetization direction of the semiconductor device 110 is a first magnetization direction (Mup) (step S110). The first magnetization direction (Mup) and the second magnetization direction (Mdown) are opposite to each other, but are not limited to this.

[0049] When the value of the input current (Ix) supplied to the semiconductor device 110 is gradually increased by the current control signal (CTL), for example, from a first value (I1) to a first threshold current value (ITH1) (step S120), the Hall resistivity (ρ xy ) or the Hall voltage (Vxy) is gradually decreased (step S130). At this time, the Hall voltage (Vxy) is referred to as an AHE signal.

[0050] That is, the Hall resistivity (ρ xy ) or the Hall voltage (Vxy) decreases (step S130).

[0051] However, when the value of the input current (Ix) supplied to the semiconductor device 110 becomes larger than the first threshold current value (ITH1) (YES in step S140), the Hall resistivity (ρ xy ) or the Hall voltage (Vxy) increases (step S150). At this time, it is assumed that the first threshold current value (ITH1) is greater than the second value (I2) and less than the third value (I3).

[0052] For example, when the value of the input current (Ix) supplied to the semiconductor device 110 increases from the first threshold current value (ITH1) to one of the plurality of values ​​(I3, I4, I5, and I6) in response to the current control signal (CTL), the Hall resistivity (ρ xy ) or the Hall voltage (Vxy) increases (step S150).

[0053] FIG. 4D is a flowchart illustrating the operation of the semiconductor device of FIG. 1 when the magnetization direction of the semiconductor device is the second magnetization direction.

[0054] 4A, 4B, and 4D, it is assumed that the values ​​of the input currents (Ix) are -I1>-I2>-ITH2>-I3>-I4>-I5>-I6. For example, the DC current densities corresponding to the values ​​(-I1, -I2, -I3, -I4, -I5, and -I6) are -0.87 MA / cm. 2 , -3.5MA / cm 2 , -4.4MA / cm 2 , -7.0MA / cm 2 , -7.8MA / cm 2 , and -10.0MA / cm 2 is.

[0055] Assuming that the value of the input current (Ix) is positive when the magnetization direction of the semiconductor device 110 is the first magnetization direction, the value of the input current (Ix) is defined as negative when the magnetization direction of the semiconductor device 110 is the second direction. That is, the value of the input current (Ix) is the same depending on the magnetization direction of the semiconductor device 110, and only the sign is defined as positive or negative.

[0056] Assume that the magnetization direction of the semiconductor device 110 is the second magnetization direction (Mdown) (step S210). When there is no external magnetic field or the external magnetic field is close to zero, and the value of the input current (Ix) supplied to the semiconductor device 110 is gradually decreased by the current control signal (CTL), for example, from zero to a first value (-I1) to a second threshold current value (-ITH2) (step S220), the Hall resistivity (ρ xy ) or the Hall voltage (Vxy) increases (step S230).

[0057] The Hall resistivity (ρ xy ) or the Hall voltage (Vxy) increases (step S230).

[0058] However, when the value of the input current (Ix) supplied to the semiconductor device 110 becomes smaller than the second threshold current value (-ITH2) (YES in step S240), the Hall resistivity (ρ xy ) or the Hall voltage (Vxy) decreases (step S250). At this time, it is assumed that the second threshold current value (-ITH2) is smaller than the second value (-I2) and larger than the third value (-I3).

[0059] When the Hall voltage (Vxy) is a function of the input current (Ix), the first threshold current value (ITH1) is a local minimum or inflection point for the minimum Hall voltage (or local minimum value Vxy_Min), and the second threshold current value (-ITH2) is a local maximum or inflection point for the maximum Hall voltage (or local maximum value Vxy_Max). For example, the absolute values ​​of the first threshold current value (ITH1) and the second threshold current value (-ITH2) may be the same or different from each other.

[0060] For example, when the value of the input current (Ix) supplied to the semiconductor device 110 is reduced from the second threshold current value (-ITH2) to one of the plurality of values ​​(-I3, -I4, -I5, and -I6) by the current control signal (CTL), the Hall resistivity (ρ xy ) or the Hall voltage (Vxy) decreases (step S250). Here, the current values ​​(-I1, -I2, -ITH2, -I3, -I4, -I5, and -I6) are conceptually set values ​​for the convenience of explanation.

[0061] Figure 5 is a graph showing the change in Hall resistivity or Hall voltage with respect to the change in the value of the input current supplied to the semiconductor device of Figure 1 when the magnetization direction of the semiconductor device is the first magnetization direction, Figure 6 is a graph showing the change in the input current input to the semiconductor device of Figure 1 over time, Figure 7 is a graph showing the change in Hall resistivity or Hall voltage with respect to the change in the magnetization direction of the semiconductor device of Figure 1 and the change in the value of the input current supplied to the semiconductor device, and Figure 8 is a graph showing the change in Hall resistivity or Hall voltage with respect to the change in the value of the input current supplied to the semiconductor device when the magnetization direction of the semiconductor device of Figure 1 is the second magnetization direction.

[0062] 1, 2, and 4A to 5, it is assumed that the magnetization direction of the semiconductor device 110 is a first magnetization direction (Mup), and the first value (I1) of the input current (Ix) is smaller than the third value (I3).

[0063] When the magnetization direction of the semiconductor device 110 is the first magnetization direction (Mup), an input current (Ix) having a first value (I1) is supplied to the non-magnetic metal layer 111 through the current electrode (M1a) at a first time point (T1).

[0064] The Hall voltage detection circuit 150 detects a first Hall voltage (Vxy_1) through the Hall voltage electrodes (M2a and M2b) generated by the anomalous Hall effect (AHE) in the ferromagnetic layer of the free magnetic layer 115 due to an input current (Ix) input to the current electrode (M1a or M1b) or a first value (I1) of the input current (Ix) flowing through the non-magnetic metal layer 111. At this time, the state of the semiconductor device 110 is defined as a first state (ST1). At a second time point (T2), an input current (Ix) having a third value (I3) is supplied to the non-magnetic metal layer 111 through the current electrode (M1a).

[0065] The Hall voltage detection circuit 150 detects, via the Hall voltage electrodes (M2a and M2b), a second Hall voltage (Vxy_2) generated by the AHE that appears in the ferromagnetic layer of the free magnetic layer 115 due to the input current (Ix) input to the current electrode (M1a or M1b) or the third value (I3) of the input current (Ix) flowing through the non-magnetic metal layer 111. At this time, the state of the semiconductor device 110 changes from the first state (ST1) to the second state (ST2). When the magnetization direction of the semiconductor device 110 is the first magnetization direction (Mup), as the value of the input current (Ix) increases from the first value (I1) to the third value (I3), the Hall resistivity (ρ xy ) decreases, and the Hall voltage (Vxy) also decreases.

[0066] At a third time point (T3), the magnetization direction of the semiconductor device 110 is changed from the first magnetization direction (Mup) to the second magnetization direction (Mdown). At the third time point (T3), the input current (Ix) is zero, and therefore the Hall voltage (Vxy) detected by the Hall voltage detection circuit 150 is also zero.

[0067] In one embodiment, the magnetization direction of the semiconductor device 110 may be changed from a first magnetization direction (Mup) to a second magnetization direction (Mdown) depending on the value of the input current (Ix), or may be changed from the first magnetization direction (Mup) to the second magnetization direction (Mdown) depending on an external magnetic field of the semiconductor device 110.

[0068] After the magnetization direction of the semiconductor device 110 is changed from the first magnetization direction (Mup) to the second magnetization direction (Mdown), at a fourth time point (T4), an input current (Ix) having a third value (-I1) is supplied to the non-magnetic metal layer 111 through the current electrode (M1a).

[0069] The Hall voltage detection circuit 150 detects, via the Hall voltage electrodes (M2a and M2b), a fourth Hall voltage (Vxy_4) generated by the AHE that appears in the ferromagnetic layer of the free magnetic layer 115 due to the input current (Ix) input to the current electrode (M1a or M1b) or the third value (-I1) of the input current (Ix) flowing through the nonmagnetic metal layer 111. At this time, the state of the semiconductor device 110 is defined as a fourth state (ST4).

[0070] At a fifth time point (T5), an input current (Ix) having a fourth value (-I3) is supplied through the current electrode (M1a) to the nonmagnetic metal layer 111. The fourth value (-I3) of the input current (Ix) is smaller than the third value (-I1).

[0071] The Hall voltage detection circuit 150 detects, via the Hall voltage electrodes (M2a and M2b), a third Hall voltage (Vxy_3) generated by the AHE that appears in the ferromagnetic layer of the free magnetic layer 115 due to the input current (Ix) input to the current electrode (M1a or M1b) or the fourth value (-I3) of the input current (Ix) flowing through the nonmagnetic metal layer 111. At this time, the state of the semiconductor device 110 changes from the fourth state (ST4) to the third state (ST3).

[0072] When the magnetization direction of the semiconductor device 110 is the second magnetization direction (Mdown), as the value of the input current (Ix) decreases from the third value (-I1) to the fourth value (-I3), the Hall resistivity (ρ xy ) increases, and the Hall voltage (Vxy) also increases.

[0073] At a sixth time point (T6), the magnetization direction of the semiconductor device 110 is changed from the second magnetization direction (Mdown) to the first magnetization direction (Mup).

[0074] In one embodiment, the magnetization direction of the semiconductor device 110 may be changed from the second magnetization direction (Mdown) to the first magnetization direction (Mup) depending on the value of the input current (Ix), or may be changed from the second magnetization direction (Mdown) to the first magnetization direction (Mup) depending on the external magnetic field of the semiconductor device 110.

[0075] At the sixth time point (T6), the input current (Ix) is zero, and therefore the Hall voltage (Vxy) detected by the Hall voltage detection circuit 150 is also zero.

[0076] After the magnetization direction of the semiconductor device 110 is changed from the second magnetization direction (Mdown) to the first magnetization direction (Mup), at the seventh time point (T7), an input current (Ix) having a first value (I1) is supplied to the non-magnetic metal layer 111 through the current electrode (M1a).

[0077] The Hall voltage detection circuit 150 detects, via the Hall voltage electrodes (M2a and M2b), a first Hall voltage (Vxy_1) generated by the AHE that appears in the ferromagnetic layer of the free magnetic layer 115 due to an input current (Ix) input to the current electrode (M1a or M1b) or a first value (I1) of the input current (Ix) flowing through the non-magnetic metal layer 111. At this time, the state of the semiconductor device 110 is again defined as a first state (ST1).

[0078] 5 to 8, the polarity and value of the Hall voltage (Vxy) of the semiconductor device 110 are simultaneously determined by the magnetization direction and the value of the input current (Ix) of the semiconductor device 110. As a result, the semiconductor device 110 has one of states (ST1 to ST4) corresponding to k bits (here, k is a natural number equal to or greater than 2, for example, when k is 2, the states are 00, 01, 11, and 10).

[0079] FIG. 9 is a graph showing changes in Hall resistivity or Hall voltage with respect to changes in the value of the input current supplied to the semiconductor device of FIG. 1 when the magnetization direction of the semiconductor device is the first magnetization direction.

[0080] 1, 2, 4A, 4B, and 9, when the magnetization direction of the semiconductor device 110 is the first magnetization direction (Mup), each state (STd, STc, STb, and STa) of the semiconductor device 110 is determined by the value of the Hall voltage (Vxy), which is determined by the value (I3, I4, I5, and I6) of the input current (Ix) supplied to the semiconductor device 110.

[0081] The value of the Hall voltage (Vxy) of the semiconductor device 110 described with reference to Figures 1 to 9 is determined by the value of the input current (Ix), and therefore has one of states (STa to STd) corresponding to two bits (e.g., 00, 01, 11, and 10). In addition, the value of the Hall voltage (Vxy) of the semiconductor device 110 described with reference to Figures 1 to 9 is determined by a combination of the magnetization direction of the semiconductor device 110 and the value of the input current (Ix), and therefore the semiconductor device 110 is used as a memory device that stores two bits of data.

[0082] The semiconductor device 110 includes a magnetic tunneling junction (MTJ) including a free magnetization layer. A memory device including the semiconductor device 110 is a magnetic random access memory (MRAM), a spin-transfer torque (STT) MRAM, or a spin-orbit torque (SOT) MRAM.

[0083] In this specification, the third value described with reference to the relevant drawings is named I3 or -I1, and the fourth value is named I4 or -I3, but this is for convenience of explanation.

[0084] Although the embodiments of the present invention have been described in detail above with reference to the drawings, the present invention is not limited to the above-described embodiments and can be modified in various ways without departing from the technical concept of the present invention. [Explanation of symbols]

[0085] 100 Memory Systems 101a, 101g Tantalum (Ta) layers 101b, 101d, 101f Palladium (Pd) layers 101c, 101e Reduced cobalt (R-Co) layer 110 Memory device or memory element 111 Non-magnetic metal layer 113 Etched part 115 Free magnetic layer 130 Input current control circuit 150 Hall voltage detection circuit CTL Current control signal ITH1, -ITH2 First and second threshold current values Ix Input current M1a, M1b current electrode M2a, M2b Hall electrodes Mdown 2nd magnetization direction Mup 1st magnetization direction RP Repeat Layer ST1~ST4 1st to 4th states T1~T7 1st to 7th time points Vxy Hall voltage ρ xx Longitudinal resistivity ρ xy Hall resistivity

Claims

1. a free magnetic layer including a ferromagnetic layer; a non-magnetic metal layer including a current electrode for receiving an input current and a Hall voltage electrode for outputting a Hall voltage; the Hall voltage is generated by the anomalous Hall effect that appears in the ferromagnetic layer of the free magnetic layer due to the input current flowing through the nonmagnetic metal layer, When the value of the input current is changed from a first value to a second value, the value of the Hall voltage has one of a minimum value and a maximum value; 10. A semiconductor device, wherein one of the first value and the second value is greater than the other of the first value and the second value.

2. When the value of the input current gradually increases from the first value to a threshold current value, the Hall voltage gradually decreases and has the minimum value at the threshold current value; 2. The semiconductor device according to claim 1, wherein the Hall voltage increases gradually as the value of the input current increases gradually from a value greater than the threshold current value to the second value.

3. When the value of the input current gradually decreases from the first value to a threshold current value, the Hall voltage gradually increases and has the maximum value at the threshold current value; 2. The semiconductor device according to claim 1, wherein the Hall voltage gradually decreases as the value of the input current gradually decreases from a value smaller than the threshold current value to the second value.

4. When the value of the input current is the first value, if the magnetic field of the free magnetic layer increases, the polarity of the Hall voltage changes from positive to negative; 2. The semiconductor device according to claim 1, wherein when the value of the input current is the second value and the magnetic field of the free magnetization layer increases, the polarity of the Hall voltage changes from negative to positive.

5. the magnetization direction of the free magnetic layer is determined to be one of a first magnetization direction and a second magnetization direction according to the value of the input current; When the magnetization direction is the first magnetization direction, the polarity of the Hall voltage is either positive or negative; the polarity of the Hall voltage when the magnetization direction is the second magnetization direction is the other one of the positive and negative; 2. The semiconductor device according to claim 1, wherein the first magnetization direction and the second magnetization direction are opposite to each other.

6. a magnetization direction of the free magnetic layer is determined to be one of a first magnetization direction and a second magnetization direction depending on an external magnetic field of the semiconductor device; When the magnetization direction is the first magnetization direction, the polarity of the Hall voltage is either positive or negative; the polarity of the Hall voltage when the magnetization direction is the second magnetization direction is the other one of the positive and negative; 2. The semiconductor device according to claim 1, wherein the first magnetization direction and the second magnetization direction are opposite to each other.

7. the Hall voltage has a first voltage value when the input current has the first value; the Hall voltage has a second voltage value when the value of the input current is the second value; the first voltage value corresponds to one of a plurality of states corresponding to a plurality of bits; 2. The semiconductor device according to claim 1, wherein the second voltage value corresponds to another one of the plurality of states.

8. a semiconductor device including a free magnetic layer including a ferromagnetic layer and a non-magnetic metal layer including a current electrode and a Hall voltage electrode; an input current control circuit that supplies an input current to the current electrode that is controlled in response to a current control signal; a Hall voltage detection circuit connected to the Hall voltage electrode, for detecting a Hall voltage generated by the anomalous Hall effect appearing in the ferromagnetic layer of the free magnetic layer in response to the input current flowing through the non-magnetic metal layer; When the value of the input current is changed from a first value to a second value, the value of the Hall voltage has one of a minimum value and a maximum value; 10. A semiconductor system, wherein one of the first value and the second value is greater than the other of the first value and the second value.

9. When the value of the input current gradually increases from the first value to a threshold current value, the Hall voltage gradually decreases and has the minimum value at the threshold current value; 9. The semiconductor system of claim 8, wherein the Hall voltage increases gradually as the input current increases from a value greater than the threshold current value to the second value.

10. When the value of the input current gradually decreases from the first value to a threshold current value, the Hall voltage gradually increases and has the maximum value at the threshold current value; 9. The semiconductor system of claim 8, wherein the Hall voltage gradually decreases as the value of the input current gradually decreases from a value smaller than the threshold current value to the second value.

11. the semiconductor device further includes a magnetic tunnel junction (MTJ) including the free magnetic layer; 9. The semiconductor system according to claim 8, wherein the semiconductor device is an MRAM, an STT-MRAM, or an SOT-MRAM.

12. 1. A method for operating a semiconductor device including a free magnetic layer including a ferromagnetic layer and a non-magnetic metal layer, comprising: supplying an input current having a first value to the non-magnetic metal layer; detecting a first Hall voltage generated by the anomalous Hall effect occurring in the ferromagnetic layer in response to an input current having the first value flowing through the non-magnetic metal layer; supplying an input current having a second value to the non-magnetic metal layer; detecting a second Hall voltage generated by the anomalous Hall effect appearing in the ferromagnetic layer by an input current having the second value flowing through the non-magnetic metal layer.

13. When the value of the input current sequentially changes from the first value to the second value, one of the first Hall voltage and the second Hall voltage has one of a minimum value and a maximum value; 13. The method of claim 12, wherein one of the first value and the second value is greater than the other of the first value and the second value.

14. When the value of the input current gradually increases from the first value to a threshold current value, one of the first Hall voltage and the second Hall voltage gradually decreases and has the minimum value at the threshold current value; 14. The method of claim 13, wherein one of the first Hall voltage and the second Hall voltage increases sequentially as the value of the input current increases sequentially from a value greater than the threshold current value to the second value.

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