A piezomagnetic-piezoelectric semiconductor device based on local magnetic field regulation

Abstract

The present invention discloses a piezomagnetic-piezoelectric semiconductor device based on local magnetic field regulation, which relates to the technical field of semiconductor design. The piezomagnetic-piezoelectric semiconductor device is composed of a first piezomagnetic layer, a second piezomagnetic layer, a piezoelectric semiconductor layer, electrodes, a coil, a DC current source, and a power supply; both ends of the piezoelectric semiconductor layer are fixedly connected to the electrodes, and the electrodes are connected in series with the power supply; the first piezomagnetic layer, the piezoelectric semiconductor layer, and the second piezomagnetic layer are connected in sequence, and the first piezomagnetic layer, the second piezomagnetic layer, and the piezoelectric semiconductor layer are arranged in the coil, and both ends of the coil are connected in series with the DC current source. Different from the traditional PN junction which is limited to forward circuit conduction and reverse circuit cut-off, this device can achieve forward circuit conduction, circuit cut-off, and reverse circuit conduction, that is, three states of the circuit.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor design. Specifically, it relates to a piezomagnetic-piezoelectric semiconductor device based on local magnetic field regulation. Background Art

[0002] A diode is a widely used semiconductor device, which is formed by a PN junction composed of a P-type semiconductor and an N-type semiconductor, plus corresponding electrode leads and packaged. Its working principle is to utilize the unidirectional conductivity of the PN junction. That is, when a forward voltage is applied to the anode and cathode of the diode, the PN junction presents low resistance and the diode conducts; when a reverse voltage is applied to the anode and cathode, the PN junction presents high resistance and the diode cuts off. The conduction and cut-off of the diode are equivalent to the one-way connection and disconnection of a switch, that is, "1" and "0". When the reverse voltage is too large, tunneling breakdown or avalanche breakdown occurs, resulting in a sharp increase in current, and the diode loses its unidirectional conductivity. If the current is not limited, it may cause permanent damage to the PN junction. For some stable switches that require bidirectional conduction and disconnection, diodes cannot meet the requirements.

[0003] The core of piezotronics lies in regulating the transport characteristics of carriers through the piezoelectric potential in piezomagnetic semiconductor materials. Once a PN junction is formed from traditional semiconductor materials, the corresponding characteristics cannot be changed; the PN junction made of piezomagnetic semiconductor materials can form a coupling of "deformation-polarization-carrier" based on the piezoelectric effect, that is, indirectly regulate the transport characteristics of carriers through strain, and can be widely applied in fields such as sensors, optoelectronic devices, and electrochemical catalysis. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention proposes a piezomagnetic-piezoelectric semiconductor device based on local magnetic field regulation, which breaks through the limitation of the unidirectional conduction of the traditional PN junction and avoids the possibility of permanent damage due to reverse voltage.

[0005] To achieve the above object, the technical solution of the present invention is: a piezomagnetic-piezoelectric semiconductor device based on local magnetic field regulation, the piezomagnetic-piezoelectric semiconductor device is composed of a first piezomagnetic layer, a second piezomagnetic layer, a piezoelectric semiconductor layer, electrodes, a coil, a DC current source, and a power supply; both ends of the piezoelectric semiconductor layer are fixedly connected to the electrodes, and the electrodes are connected in series with the power supply; the first piezomagnetic layer, the piezoelectric semiconductor layer, and the second piezomagnetic layer are connected in sequence, and the first piezomagnetic layer, the second piezomagnetic layer, and the piezoelectric semiconductor layer are arranged in the coil, and both ends of the coil are connected in series with the DC current source.

[0006] Furthermore, the lengths of the first piezomagnetic layer and the second piezomagnetic layer are equal, and are both 0.01 - 0.5 of the length of the piezoelectric semiconductor layer; the length of the piezoelectric semiconductor layer is 0.1 - 10 μm.

[0007] Furthermore, the thicknesses of the first piezomagnetic layer and the second piezomagnetic layer are equal, and each is 1 / 6 to 2 times the central thickness of the piezoelectric semiconductor layer.

[0008] Furthermore, the first piezomagnetic layer and the second piezomagnetic layer are made of the same piezomagnetic material.

[0009] Furthermore, the direction of the magnetic field generated by the coil is the same as the polarization axis directions of the first piezomagnetic layer and the second piezomagnetic layer.

[0010] Furthermore, the magnetic field strength H generated by the coil is:

[0011] where n is the number of turns of the coil; I is the magnitude of the current flowing through the coil, and l is the length of a single-turn coil.

[0012] Furthermore, the length of the single-turn coil is 1 to 10 cm.

[0013] Furthermore, the widths of the first piezomagnetic layer, the second piezomagnetic layer and the piezoelectric semiconductor layer are equal.

[0014] Furthermore, the widths and the total thicknesses of the first piezomagnetic layer, the second piezomagnetic layer and the piezoelectric semiconductor layer do not exceed 0.1 of the length of the piezoelectric semiconductor layer.

[0015] Compared with the prior art, the present invention has the following beneficial effects: Different from the PN junction formed by P-type semiconductor and N-type semiconductor, the unidirectional circuit conduction, circuit cut-off, breakdown caused by excessive reverse voltage and possible permanent damage. This device forms a composite structure by the first piezomagnetic layer, the second piezomagnetic layer and the piezoelectric semiconductor layer. When a forward or reverse voltage is applied to the left and right ends of the piezoelectric semiconductor layer and a magnetic field is applied to this device, a potential barrier and potential well are indirectly formed locally in the piezoelectric semiconductor layer, and the forward circuit conduction, circuit cut-off and reverse circuit conduction of the electrical signal can be realized, that is, the three states of the circuit, and this device is safer and more stable than the PN junction. This piezomagnetic-piezoelectric semiconductor device forms a coupling of "magnetic field - deformation - polarization - carriers", and the transport characteristics of carriers can be indirectly regulated by a non-contact and highly penetrating magnetic field. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is a performance simulation diagram of the piezomagnetic-piezoelectric semiconductor device provided by the present invention: Figure 1A is the current density - V curve under different magnetic field strengths; Figure 1B is the potential - z curve under different voltages, that is, the distribution diagram of the potential of the piezoelectric semiconductor layer in the length direction;

[0017] Figure 2 is a schematic structural diagram of the piezomagnetic-piezoelectric semiconductor device provided in Embodiment 1;

[0018] Figure 3It is a schematic diagram of the piezomagnetic-piezoelectric semiconductor device structure provided by Embodiment 2. Detailed implementation manners

[0019] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. What is described here is only for illustrating and explaining the present invention, and is not used to limit the present invention.

[0020] The present invention provides a piezomagnetic-piezoelectric semiconductor device based on local piezomagnetism. The piezomagnetic-piezoelectric semiconductor device is composed of a first piezomagnetic layer 2, a second piezomagnetic layer 3, a piezoelectric semiconductor layer 1, electrodes 4, a coil 6, a DC current source 7, and a power supply 5. Both ends of the piezoelectric semiconductor layer 1 are fixedly connected to the electrodes 4 respectively. The electrodes 4 are connected in series with the power supply 5. By means of this power supply 5, the voltages on the two electrodes 4 are adjusted, that is, the voltages at the left and right ends of the piezoelectric semiconductor layer 1 are obtained. The first piezomagnetic layer 2, the piezoelectric semiconductor layer 1, and the second piezomagnetic layer 3 are connected in sequence, and the first piezomagnetic layer 2, the second piezomagnetic layer 3, and the piezoelectric semiconductor layer 1 are arranged in the coil 6. Both ends of the coil 6 are connected in series with the DC current 7 source.

[0021] Those skilled in the art know that piezoelectric semiconductors have both piezoelectric effect and semiconductor physical properties. Common ones are II-VI group compounds such as CdS, CdSe, ZnO, ZnS, CdTe, ZnTe, etc., and III-V group compounds such as GaAs, GaSb, InAs, InSb, AIN, etc.

[0022] The first piezomagnetic layer 2 and the second piezomagnetic layer 3 are made of the same piezomagnetic material. Common piezomagnetic materials include metallic piezomagnetic materials, ferrite piezomagnetic materials, and rare earth piezomagnetic materials. Moreover, the lengths, widths, and thicknesses of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are equal. The length of the piezoelectric semiconductor layer 1 is 0.1 - 10 μm. The lengths of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are both 0.01 - 0.5 of the length of the piezoelectric semiconductor layer 1. The widths of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are equal to the width of the piezoelectric semiconductor layer 1. The thicknesses of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are both 1 / 6 - 2 times the central thickness of the piezoelectric semiconductor layer 1. The widths and total thicknesses of the first piezomagnetic layer 2, the second piezomagnetic layer 3, and the piezoelectric semiconductor layer 1 do not exceed 0.1 of the length of the piezoelectric semiconductor layer 1. The first piezomagnetic layer 2 and the second piezomagnetic layer 3 generate the same longitudinal expansion and contraction under the action of a magnetic field, causing the same strain on the upper and lower sides of the piezoelectric semiconductor layer 1. Due to the piezoelectric effect, the strain of the piezoelectric semiconductor layer 1 causes longitudinal potential wells and potential barriers in the middle of the piezoelectric semiconductor layer 1, affecting the transport characteristics of carriers. When voltages are applied to both ends of the piezoelectric semiconductor layer 1, it can be considered that the electric potential and current of the piezoelectric semiconductor layer 1 are along its axial direction and only related to the axial position. And at this time, the current flowing through the piezoelectric semiconductor layer 1 is more sensitive to the change of the magnetic field.

[0023] The magnetic field direction generated by the coil 6 is the same as the polarization axis directions of the first piezomagnetic layer 2 and the second piezomagnetic layer 3. The magnitude of the magnetic field is determined by adjusting the number of turns, the length of a single turn, and the magnitude of the current of the coil 6. The magnetic field strength H generated by the coil 6 is:

[0024] where n is the number of turns of the coil; I is the magnitude of the current flowing through the coil, and l is the length of a single-turn coil. The smaller the length of a single-turn coil is, the better, as this facilitates achieving a large change in the magnetic field magnitude with a small change in the current magnitude. Therefore, the length of a single-turn coil is set to 1 - 10 cm.

[0025] When the coil 6 is energized to generate a magnetic field, the magnetic field direction of this piezomagnetic - piezoelectric semiconductor device is along the polarization directions of the first piezomagnetic layer 2 and the second piezomagnetic layer 3. Due to the magnetostrictive effect, longitudinal strain is generated in the local first piezomagnetic layer 2 and second piezomagnetic layer 3. Since the first piezomagnetic layer 2, the piezoelectric semiconductor layer 1, and the second piezomagnetic layer 3 are connected in sequence, the strain of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 causes longitudinal strain to be locally generated in the piezoelectric semiconductor layer 1. Due to the piezoelectric effect, potential wells and potential barriers are further formed in the local area of the piezoelectric semiconductor layer 1. The greater the magnetic field strength, the more significant these potential wells and potential barriers are.

[0026] When the magnitude of the applied magnetic field remains unchanged, the state of the circuit can be controlled by applying a voltage across the two ends of the piezoelectric semiconductor layer 1. If the forward voltage is large enough to overcome the potential wells and potential barriers, that is, the forward voltage exceeds the voltage threshold for the forward circuit to conduct and disconnect, then the circuit conducts forward; if the reverse voltage is large enough to overcome the potential wells and potential barriers, that is, the reverse voltage exceeds the voltage threshold for the reverse circuit to conduct and disconnect, then the circuit conducts reversely; if the voltage across the two ends is not large enough, that is, the voltage is within the range of the above two voltage thresholds, then the circuit cannot conduct.

[0027] Meanwhile, when the voltage applied across the two ends of the piezoelectric semiconductor layer 1 remains unchanged, the state of the circuit can also be controlled by regulating the magnetic field. If no magnetic field is applied, the circuit of the piezoelectric semiconductor layer 1 conducts, and the direction of the current is determined by the voltage across the two ends of the piezoelectric semiconductor layer 1. When a magnetic field is applied, it causes potential wells and potential barriers to be formed in the piezoelectric semiconductor layer 1, further hindering the longitudinal current, that is, weakening the current. If the potential wells and potential barriers formed by the applied magnetic field cannot cause the circuit to disconnect, then the magnetic field is less than the threshold for the circuit to conduct and disconnect; if the potential wells and potential barriers formed by the applied magnetic field cause the circuit to disconnect, then the magnetic field exceeds the threshold for the circuit to conduct and disconnect.

[0028] The piezomagnetic-piezoelectric semiconductor device of the present invention was imported into the numerical calculation software COMSOL for simulation, and its performance results are shown in Figure 1. In the simulation, the materials of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are both CoFe2O4, and ZnO doped with n-type carriers is used as the material of the piezoelectric semiconductor layer 1. The specific structural parameters used are as follows: the lengths of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are both 2 μm, the length of the piezoelectric semiconductor layer 1 is 20 μm, the thickness of the piezoelectric semiconductor layer 1 is 30 nm, the thicknesses of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are both 35 nm, and the widths of the piezoelectric semiconductor layer 1, the first piezomagnetic layer 2, and the second piezomagnetic layer 3 are all 100 nm. A potential V is applied to the right end of the device, and a potential -V is applied to the left end. The value of the potential V varies between -1.5 V and 1.5 V, so the voltage acting on both ends of the device varies between -3 V and 3 V.

[0029] Figure 1A is the current density-V curve, and the initial concentration of n-type carriers is n0 = 1×10 21 m -3 , when the magnetic field magnitude is H = 4×10 5 A / m and the potential V is 0, no current is generated; when the potential V increases to 0.5 V, the current density is negative, that is, there is a current passing from right to left in the piezoelectric semiconductor layer 1; when the potential V decreases to -0.5 V, the current density is positive, that is, there is a current passing from left to right in the piezoelectric semiconductor layer 1. When the magnetic field magnitude is H = 8×10 5 A / m, no current is generated when the potential V is between -0.5 V and 0.5 V; when the potential V is greater than 1 V, the current density is negative, that is, there is a current passing from right to left in the piezoelectric semiconductor layer 1; when the potential V is less than -1 V, the current density is positive, that is, there is a current passing from left to right in the piezoelectric semiconductor layer 1. From Figure 1A it can be seen that the greater the applied magnetic field, the greater the difficulty for the voltage to overcome the potential well barrier to make the circuit conduct, and the wider the platform width of the potential V range corresponding to the current density of 0.

[0030] Figure 1B is the potential-z curve, which can represent the distribution of the average potential along the axial direction on the cross-section perpendicular to the axial direction in the device, where the initial concentration of n-type carriers is n0 = 1×10 21 m -3 . When the magnetic field magnitude is H = 8×10 5 A / m, when the potential V is 0.6 V, the potential well hinders the current and the circuit cannot conduct; when the potential V is 1.5 V, the potential well is overcome, the circuit can conduct, and the potential magnitude changes monotonically along the longitudinal direction.

[0031] From Figure 1AAs can be seen from the results, for the potential distribution platform corresponding to a current density of 0, increasing the magnetic field strength can increase the width of the potential platform. That is, it increases the range of potential thresholds corresponding to the forward or reverse conduction of the circuit. Therefore, there are the following two ways to regulate the current:

[0032] 1) Keep the magnetic field size unchanged and regulate the current state and size flowing through the device by the voltage at both ends:

[0033] Apply a voltage across the piezoelectric semiconductor layer 1. When the voltage at both ends is 0, the current flowing through the device is 0 because the magnetic field can cause potential barriers and potential wells to form in the piezoelectric semiconductor layer 1, hindering the flow of current. When the voltage at both ends of the piezoelectric semiconductor layer 1 reaches a certain critical value, the potential wells and potential barriers inside the piezoelectric semiconductor layer 1 are just offset, and the current flowing through the device is no longer 0. When the voltage at both ends of the piezoelectric semiconductor layer 1 is even larger, the current is even larger thereafter.

[0034] If the positive direction of the current is defined as flowing in from the right and flowing out from the left. When the magnitude of the applied magnetic field H is a certain constant value H1, apply a potential V to the right end of the piezomagnetic-piezoelectric semiconductor device and a potential -V to the left end (i.e., the potential at the right end - the potential at the left end = the voltage at both ends = 2V). Then a positive constant potential threshold V1 and a negative constant potential threshold V2 will be generated accordingly, and V2 < 0 < V1.

[0035] Specifically, when the potential at the right end - the potential at the left end = the voltage at both ends = 2V1, the positive current density reaches the critical value: when V > V1, the positive current density is greater than 0, and a positive current is generated. When the potential at the right end - the potential at the left end = the voltage at both ends = 2V2, the negative current density reaches the critical value: when V < V2, the absolute value of the negative current density is greater than 0, and a negative current is generated. When V2 < V < V1, the current density is 0, that is, the circuit is disconnected.

[0036] The magnitudes of the voltage thresholds V1 and V2 are related to the piezomagnetic-piezoelectric semiconductor composite structure and the applied magnetic field. Specifically, they are jointly determined by the parameters of the piezomagnetic layer and the piezoelectric semiconductor layer such as length, width, thickness, and the selected materials, as well as the magnitude H1 of the applied constant magnetic field. Inputting the specific conditions into COMSOL can obtain the results shown in Figure 1.

[0037] 2) Keep the voltage at both ends unchanged and regulate the current state and size flowing through the device by the magnetic field size:

[0038] Apply a constant voltage at both ends. When it is detected that there is current passing through the device, the magnetic field size can be adjusted. The magnetic field can cause potential barriers and potential wells to form in the piezoelectric semiconductor layer 1, hindering the flow of current. When the magnetic field is large enough, the current cannot flow, that is, the circuit is disconnected.

[0039] If the positive direction of the current is defined as flowing in from the right side and flowing out from the left side. When the magnitude H of the applied magnetic field is any value greater than 0, a potential V is applied to the right end of the piezomagnetic-piezoelectric semiconductor, and a potential -V is applied to the left end. When the applied potential V = V3 (i.e., the potential at the right end - the potential at the left end = the voltage across both ends = 2V = 2V3), a constant magnetic field threshold H3 will be correspondingly generated.

[0040] Specifically, when the magnitude H of the applied magnetic field = H3, the current density reaches the critical point: when 0 < H < H3, the current density is greater than 0, and the current direction at this time is determined by V3. When V3 > 0, the current is in the positive direction; when V3 < 0, the current is in the reverse direction. When H > H3, the current density is 0, that is, the circuit is disconnected.

[0041] The magnitude of the magnetic field threshold H3 is related to the piezomagnetic-piezoelectric semiconductor and the applied voltage. Specifically, it is jointly determined by the parameters of the piezomagnetic layer and the piezoelectric semiconductor layer, such as length, width, thickness, the selected materials, and the magnitude V3 of the applied constant potential.

[0042] Embodiment 1

[0043] As Figure 2 The present invention provides a piezomagnetic-piezoelectric semiconductor device, which is composed of a first piezomagnetic layer 2, a second piezomagnetic layer 3, a piezoelectric semiconductor layer 1, electrodes 4, a coil 6, a DC current source 7, and a power supply 5; both ends of the piezoelectric semiconductor layer 1 are fixedly connected to the electrodes 4, and the electrodes 4 are connected in series with the power supply 5; the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are respectively arranged on the upper and lower sides of the piezoelectric semiconductor layer 1, and the first piezomagnetic layer 2, the second piezomagnetic layer 3, and the piezoelectric semiconductor layer 1 are arranged in the coil 6, and both ends of the coil 6 are connected in series with the DC current source 7. Figure 2 The arrow to the right in the piezoelectric semiconductor layer 1 indicates the c-axis direction of the piezoelectric semiconductor layer. Figure 2 The coordinate system in the upper left corner is the material coordinate system of the piezoelectric semiconductor layer. Figure 2 The upward arrows in the first piezomagnetic layer 2 and the second piezomagnetic layer 3 indicate the polarization directions of the piezomagnetic layers. Figure 2 The coordinate system in the upper right corner is the material coordinate system of the piezomagnetic layer. When the piezomagnetic-piezoelectric semiconductor device is in a magnetic field along the polarization direction of the piezomagnetic layer, the first piezomagnetic layer 2 and the second piezomagnetic layer 3 generate longitudinal expansion and contraction due to the piezomagnetic constant h 31 resulting in longitudinal expansion and contraction of the piezoelectric semiconductor layer 1 as well.

[0044] The lengths of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are equal, and each is 0.5 times the length of the piezoelectric semiconductor layer 1. The length of the piezoelectric semiconductor layer 1 is 0.1 μm. The thicknesses of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are equal, and each is 2 times the central thickness of the piezoelectric semiconductor layer 1. The widths of the first piezomagnetic layer 2, the second piezomagnetic layer 3 and the piezoelectric semiconductor layer 1 are equal. The widths and the total thicknesses of the first piezomagnetic layer 2, the second piezomagnetic layer 3 and the piezoelectric semiconductor layer 1 are each 0.1 times the length of the piezoelectric semiconductor layer 1. The materials of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are both CoFe2O4. The material of the piezoelectric semiconductor layer 1 is ZnO. The direction of the magnetic field generated by the coil is the same as the polarization axis direction of the first piezomagnetic layer 2 and the second piezomagnetic layer 3, and the magnetic field strength H generated by the coil is:

[0045] where n is the number of turns of the coil; I is the magnitude of the current flowing through the coil, and l is the length of a single-turn coil, and the length of a single-turn coil is 10 cm.

[0046] When the coil and the current flowing through the coil are unchanged, the state of the circuit is controlled by changing the voltage across the piezoelectric semiconductor layer. When the forward voltage is large enough to overcome the potential well barrier, that is, the forward voltage exceeds the voltage threshold for the forward circuit to conduct and disconnect, the circuit conducts forward; when the reverse voltage is large enough to overcome the potential well barrier, that is, the reverse voltage exceeds the voltage threshold for the reverse circuit to conduct and disconnect, the circuit conducts reversely; when the voltage across both ends is not large enough, that is, the voltage is within the range of the above two voltage thresholds, the circuit cannot conduct.

[0047] At the same time, when the voltage across the piezoelectric semiconductor layer remains unchanged, the state of the circuit can also be controlled by regulating the magnetic field generated by the coil. When no magnetic field is applied, the circuit of the piezoelectric semiconductor layer conducts, and the direction of the current is determined by the voltage across both ends. When a magnetic field is applied, it causes local potential well barriers to form in the piezoelectric semiconductor layer, further hindering the longitudinal current, that is, weakening the current. When the potential well barriers formed by the applied magnetic field cannot make the circuit disconnect, the magnetic field is less than the threshold for the circuit to conduct and disconnect; when the potential well barriers formed by the applied magnetic field make the circuit disconnect, the magnetic field exceeds the threshold for the circuit to conduct and disconnect.

[0048] In short, the current state and magnitude of the current flowing through the piezoelectric semiconductor layer can be regulated by regulating the voltage across the piezoelectric semiconductor layer and the magnitude of the magnetic field generated by the coil, so that the device can achieve forward circuit conduction, circuit cut-off, and reverse circuit conduction of the electrical signal, that is, the three states of the circuit.

[0049] Embodiment 2

[0050] As Figure 3A local piezomagnetic-piezoelectric semiconductor device is provided. The piezomagnetic-piezoelectric semiconductor device is composed of a first piezomagnetic layer 2, a second piezomagnetic layer 3, a piezoelectric semiconductor layer 1, an electrode 4, a coil 6, a DC current source 7, and a power supply 5. The two ends of the piezoelectric semiconductor layer 1 are fixedly connected to the electrode 4 respectively, and the electrode 4 is connected in series with the power supply 5. Grooves are provided on both the upper and lower sides of the piezoelectric semiconductor layer 1, and the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are respectively arranged in the grooves of the piezoelectric semiconductor layer 1. And the first piezomagnetic layer 2, the second piezomagnetic layer 3 and the piezoelectric semiconductor layer 1 are arranged in the coil 6, and the two ends of the coil 6 are connected in series with the DC current source 7. Figure 3 In Figure 3 , the arrow to the right of the piezoelectric semiconductor layer 1 represents the c-axis direction of the piezoelectric semiconductor layer. Figure 3 In Figure 3 , the coordinate system in the upper left corner is the material coordinate system of the piezoelectric semiconductor layer. Figure 3 In Figure 3 , the upward arrows in the first piezomagnetic layer 2 and the second piezomagnetic layer 3 represent the polarization directions of the piezomagnetic layers. Figure 3 In Figure 3 , the coordinate system in the upper right corner is the material coordinate system of the piezomagnetic layer. When the piezomagnetic-piezoelectric semiconductor device is in a magnetic field along the polarization direction of the piezomagnetic layer, the first piezomagnetic layer 2 and the second piezomagnetic layer 3 generate longitudinal expansion and contraction due to the piezomagnetic constant h 31 which causes the piezoelectric semiconductor layer 1 to also generate longitudinal expansion and contraction.

[0051] The lengths of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are equal, and both are 0.01 times the length of the piezoelectric semiconductor layer 1, and the length of the piezoelectric semiconductor layer 1 is 10 μm. The thicknesses of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are equal, and both are 1 / 6 times the central thickness of the piezoelectric semiconductor layer 1. The widths of the first piezomagnetic layer 2, the second piezomagnetic layer 3 and the piezoelectric semiconductor layer 1 are equal. The widths and the total thicknesses of the first piezomagnetic layer 2, the second piezomagnetic layer 3 and the piezoelectric semiconductor layer 1 are all 0.05 times the length of the piezoelectric semiconductor layer 1. The materials of the first piezomagnetic layer 2 and the second piezomagnetic layer 3 are both CoFe2O4. The material of the piezoelectric semiconductor layer 1 is ZnO. The magnetic field direction generated by the coil is the same as the polarization axis direction of the first piezomagnetic layer 2 and the second piezomagnetic layer 3, and the magnetic field strength H generated by the coil is:

[0052] where n is the number of turns of the coil; I is the magnitude of the current flowing through the coil, and l is the length of a single-turn coil, and the length of a single-turn coil is 1 cm.

[0053] When the coil and the current flowing through the coil remain unchanged, the state of the circuit is controlled by changing the voltage across the piezoelectric semiconductor layer. If the forward voltage is large enough to overcome the potential well barrier, that is, the forward voltage exceeds the voltage threshold for the forward circuit to conduct and disconnect, then the circuit conducts forward; if the reverse voltage is large enough to overcome the potential well barrier, that is, the reverse voltage exceeds the voltage threshold for the reverse circuit to conduct and disconnect, then the circuit conducts reversely; if the voltage across both ends is not large enough, that is, the voltage is within the range of the above two voltage thresholds, then the circuit cannot conduct.

[0054] At the same time, when the voltage across the piezoelectric semiconductor layer remains unchanged, the state of the circuit can also be controlled by regulating the magnetic field generated by the coil. Without applying a magnetic field, the circuit of the piezoelectric semiconductor layer conducts, and the direction of the current is determined by the voltage across both ends. When a magnetic field is applied, it causes local potential well barriers to form in the piezoelectric semiconductor layer, further hindering the longitudinal current, that is, weakening the current. When the potential well barrier formed by the applied magnetic field cannot disconnect the circuit, then the magnetic field is less than the threshold for the circuit to conduct and disconnect; when the potential well barrier formed by the applied magnetic field disconnects the circuit, then the magnetic field exceeds the threshold for the circuit to conduct and disconnect.

[0055] In short, the current state and magnitude of the current flowing through the piezoelectric semiconductor layer can be regulated by controlling the voltage across the piezoelectric semiconductor layer and the magnitude of the magnetic field generated by the coil, enabling the device to achieve forward circuit conduction, circuit cut-off, and reverse circuit conduction of electrical signals, that is, the three states of the circuit.

Claims

1. A piezomagnetic-piezoelectric semiconductor device based on local magnetic field regulation, characterized in that, The piezomagnetic-piezoelectric semiconductor device is composed of a first piezomagnetic layer (2), a second piezomagnetic layer (3), a piezoelectric semiconductor layer (1), an electrode (4), a coil (6), a DC current source (7), and a power supply (5); both ends of the piezoelectric semiconductor layer (1) are fixedly connected to the electrode (4), and the electrode (4) is connected in series with the power supply (5); the first piezomagnetic layer (2), the piezoelectric semiconductor layer (1), and the second piezomagnetic layer (3) are connected in sequence, and the first piezomagnetic layer (2), the second piezomagnetic layer (3), and the piezoelectric semiconductor layer (1) are arranged in the coil (6), and both ends of the coil (6) are connected in series with the DC current source (7); The first piezomagnetic layer (2) and the second piezomagnetic layer (3) have equal lengths, and are both 0.01 to 0.5 times the length of the piezoelectric semiconductor layer (1); the length of the piezoelectric semiconductor layer (1) is 0.1 to 10 μm; The first piezomagnetic layer (2) and the second piezomagnetic layer (3) have equal thicknesses, and are both 1 / 6 to 2 times the central thickness of the piezoelectric semiconductor layer (1).

2. The piezomagnetic-piezoelectric semiconductor device according to claim 1, characterized in that, The first piezomagnetic layer (2) and the second piezomagnetic layer (3) are made of the same piezomagnetic material.

3. The piezomagnetic-piezoelectric semiconductor device according to claim 1, characterized in that, The magnetic field direction generated by the coil (6) is the same as the polarization axis direction of the first piezomagnetic layer (2) and the second piezomagnetic layer (3).

4. The piezomagnetic-piezoelectric semiconductor device according to claim 1, characterized in that, The magnetic field strength H generated by the coil (6) is as follows: Where, n is the number of turns of the coil; I is the magnitude of the current flowing through the coil, and l is the length of a single-turn coil.

5. The piezomagnetic-piezoelectric semiconductor device according to claim 4, characterized in that, The length of the single-turn coil is 1 to 10 cm.

6. The piezomagnetic-piezoelectric semiconductor device according to claim 1, characterized in that, The first piezomagnetic layer (2), the second piezomagnetic layer (3), and the piezoelectric semiconductor layer (1) have equal widths.

7. The piezomagnetic-piezoelectric semiconductor device according to claim 1, characterized in that, The widths and the total thicknesses of the first piezomagnetic layer (2), the second piezomagnetic layer (3), and the piezoelectric semiconductor layer (1) do not exceed 0.1 times the length of the piezoelectric semiconductor layer (1).

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