Light detecting element, receiving device and light sensor device

Abstract

The present invention provides a light detecting element, a receiving device and a light sensor device having good responsiveness to light. The light detecting element comprises a magnetic element, the magnetic element comprises a first ferromagnetic layer, a second ferromagnetic layer and a spacer layer sandwiched by the first ferromagnetic layer and the second ferromagnetic layer, and the first ferromagnetic layer is irradiated with light from a direction intersecting with the stacking direction of the magnetic element.

Description

Technical Field

[0001] The present invention relates to a light detecting element, a receiving device and a light sensor device. Background Art

[0002] Photoelectric conversion elements are used in various applications.

[0003] For example, a receiving device that receives an optical signal using a photodiode is described in Patent Document 1. The photodiode is, for example, a pn junction diode using a pn junction of a semiconductor, and converts light into an electrical signal.

[0004] In addition, for example, Patent Document 2 describes a photosensor using a pn junction of a semiconductor and an image sensor using the photosensor.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2001-292107

[0008] Patent Document 2: U.S. Patent No. 9842874 Summary of the invention

[0009] Problems to be solved by the invention

[0010] Photodetection elements using pn junctions of semiconductors are widely used, but new photodetection elements are required for further development. In addition, photodetection elements convert light into electrical signals, and there is a demand for improved conversion accuracy.

[0011] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a light detection element, a receiving device, and a light sensor device having good responsiveness to light.

[0012] Methods for solving problems

[0013] In order to solve the above-mentioned problems, the following means are provided.

[0014] (1) A first mode of light detection element comprises: a magnetic element having a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, wherein the first ferromagnetic layer is irradiated with light from a direction intersecting with a stacking direction of the magnetic element.

[0015] (2) The light detection element of the above-mentioned method can also be constructed to further include: a first electrode and a second electrode, which clamp the magnetic element in the stacking direction, and the side surface of at least one of the first electrode and the second electrode is in contact with the side surface of the magnetic element in at least a portion of the same imaginary plane, and the light is irradiated toward the first ferromagnetic layer from the side of the imaginary plane.

[0016] (3) The light detecting element of the above aspect may be configured such that a part of the side surface of the magnetic element is a flat surface, and the light is irradiated onto the flat surface.

[0017] (4) In the above-described light detecting element, a part of the side surface of the magnetic element may be a flat surface, and the flat surface may be in contact with the imaginary plane.

[0018] (5) The light detecting element of the above aspect may further include an oxide film that covers the flat surface and can transmit the light.

[0019] (6) The light detecting element of the above aspect may further include a heat generating portion, wherein the heat generating portion is located behind the magnetic element in the light irradiation direction in which the light is mainly irradiated with respect to the magnetic element.

[0020] (7) The light detection element of the above-mentioned method may also have: an expansion portion, the heat generating portion is located at a position capable of heating the expansion portion, the expansion portion is located behind the magnetic element in the light irradiation direction relative to the main irradiation of the magnetic element, and the linear thermal expansion coefficient of the expansion portion is greater than the linear thermal expansion coefficient of the first ferromagnetic layer.

[0021] (8) In the above-described aspect of the photodetection element, the light may be light including a high-frequency optical signal and having a varying intensity.

[0022] (9) In the above-described aspect of the photodetection element, the light may be light transmitted through a wavelength filter.

[0023] (10) A receiving device according to a second aspect includes the light detecting element according to the above aspect.

[0024] (11) A photosensor device according to a third aspect includes the photosensor element according to the above aspect.

[0025] Effects of the Invention

[0026] The light detecting element, the receiving device, and the light sensor device of the above-described embodiment have good responsiveness to light. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a perspective view of the light detection element according to the first embodiment.

[0028] Figure 2 It is a cross-sectional view of the light detection element according to the first embodiment.

[0029] Figure 3 It is a top view of the light detection element according to the first embodiment.

[0030] Figure 4 It is a diagram for explaining a first mechanism of a first operation example of the photodetection element according to the first embodiment.

[0031] Figure 5 It is a diagram for explaining the second mechanism of the first operation example of the photodetection element according to the first embodiment.

[0032] Figure 6 It is a diagram for explaining the first mechanism of the second operation example of the photodetection element according to the first embodiment.

[0033] Figure 7 It is a diagram for explaining the second mechanism of the second operation example of the photodetection element according to the first embodiment.

[0034] Figure 8 This is a diagram for explaining another example of the second operation example of the photodetection element according to the first embodiment.

[0035] Fig. 9 This is a diagram for explaining another example of the second operation example of the photodetection element according to the first embodiment.

[0036] Fig.10 It is a cross-sectional view of the light detection element according to the first modification.

[0037] Fig.11 It is a cross-sectional view of a light detection element according to a second modification.

[0038] Fig.12 It is a cross-sectional view of a light detection element according to a third modified example.

[0039] Fig.13 It is a cross-sectional view of a light detection element according to a fourth modified example.

[0040] Fig.14 It is a cross-sectional view of the light detection element according to the second embodiment.

[0041] Fig.15 It is a cross-sectional view of a light detection element according to a third embodiment.

[0042] Fig.16 It is a cross-sectional view of a light detection element according to a fourth embodiment.

[0043] Fig.17 This is a block diagram of a transmitting and receiving device according to the first application example.

[0044] Fig.18This is a conceptual diagram of an example of a communication system.

[0045] Fig.19 This is a conceptual diagram of a cross section of a photosensor device according to a second application example.

[0046] Fig. 20 This is a schematic diagram of an example of a terminal device.

[0047] Explanation of symbols:

[0048] 1...1st ferromagnetic layer; 2...2nd ferromagnetic layer; 3...spacer layer; 10, 11, 12, 13...magnetic element; 20, 21, 22...1st electrode; 30, 31, 32...2nd electrode; 10s, 11s, 12s, 13s, 20s, 21s, 22s, 30s, 31s, 32s...side surface; 40...light irradiation part; 50...insulating layer; 60...oxide film; 70...heat generating part; 80...expansion part; 100, 101, 102, 103, 104, 105, 106, 107...light detecting element; 11 0...circuit board; 111...analog-to-digital converter; 112...output terminal; 120...wiring layer; 121...wiring; 122...interlayer insulating film; 300...receiving device; 301...light detecting element; 302...signal processing unit; 400...transmitting device; 401...light source; 402...electrical signal generating element; 403...light modulating element; 500, 600...terminal device; 1000...transmitting and receiving device; 2000...optical sensor device; CA...camera; F...wavelength filter; R...lens; S...optical sensor. DETAILED DESCRIPTION

[0049] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings as appropriate. In the drawings used in the following description, in order to facilitate the understanding of the features, the features are sometimes enlarged for convenience, and the dimensional ratios of the components are sometimes different from the actual ones. The materials, dimensions, etc. illustrated in the following description are examples, and the present invention is not limited thereto, and can be implemented with appropriate changes within the scope of achieving the effects of the present invention.

[0050] Define the direction. The stacking direction of the magnetic element 10 is set to the z direction, a direction in the plane perpendicular to the z direction is set to the x direction, and the direction perpendicular to the x direction and the z direction is set to the y direction. The z direction is an example of a stacking direction. In the following, the +z direction is sometimes expressed as "up" and the -z direction is expressed as "down". The +z direction is the direction from the second ferromagnetic layer 2 toward the first ferromagnetic layer 1. Up and down are not necessarily consistent with the direction in which gravity is applied.

[0051] (First embodiment)

[0052] Figure 1 It is a perspective view of the light detection element 100 according to the first embodiment. Figure 2 It is a yz cross-sectional view of the photodetection element 100 according to the first embodiment. Figure 3 This is a plan view of the light detection element 100 according to the first embodiment as viewed from the z direction.

[0053] The light detection element 100 replaces the state or change of the state of the irradiated light L with an electrical signal. The light L in this specification is not limited to visible light, but also includes infrared light with a longer wavelength than visible light and ultraviolet light with a shorter wavelength than visible light. The wavelength of visible light is, for example, greater than 380nm and less than 800nm. The wavelength of infrared light is, for example, greater than 800nm ​​and less than 1mm. The wavelength of ultraviolet light is, for example, greater than 200nm and less than 380nm.

[0054] The photodetection element 100 includes, for example, a magnetic element 10 , a first electrode 20 , a second electrode 30 , a light irradiation unit 40 , and an insulating layer 50 .

[0055] The light irradiation part 40 is a part which emits the light L propagated from a light source, for example. The light L emitted from the light irradiation part 40 is irradiated to the side surface 10s of the magnetic element 10. The light irradiation part 40 is opposed to the side surface 10s of the magnetic element 10, for example.

[0056] Light L irradiates the magnetic element 10 from a direction intersecting the z direction. Light L irradiates the side surface 10s of the magnetic element 10 from the y direction, for example. Hereinafter, the direction in which the light is mainly irradiated to the magnetic element 10 is referred to as the light irradiation direction. Main irradiation means that the intensity of light irradiated from this direction is greater than the intensity of light irradiated from other directions. Figure 1 and Figure 2 In FIG. 1 , the y direction is the light irradiation direction of the magnetic element 10. The light L is, for example, light containing a high-frequency optical signal and having a variable intensity, or light having a controlled wavelength region through a wavelength filter. The high-frequency optical signal is, for example, a signal having a frequency of 100 MHz or more.

[0057] The first electrode 20 is in contact with the first surface of the magnetic element 10. The first surface is the surface on the first ferromagnetic layer 1 side of the magnetic element 10 in the z direction. The second electrode 30 is in contact with the second surface of the magnetic element 10. The second surface is the surface on the second ferromagnetic layer 2 side of the magnetic element 10 in the z direction. The first electrode 20 and the second electrode 30 sandwich the magnetic element 10 in the z direction, for example.

[0058] The first electrode 20 and the second electrode 30 are made of a conductive material. The first electrode 20 and the second electrode 30 are made of, for example, a metal such as Cu, Al, Au, or Ru. Ta or Ti may be stacked on top and bottom of these metals. In addition, as the first electrode 20 and the second electrode 30, a stacked film of Cu and Ta, a stacked film of Ta, Cu and Ti, or a stacked film of Ta, Cu and TaN may be used. In addition, as the first electrode 20 and the second electrode 30, TiN or TaN may be used.

[0059] The first electrode 20 and the second electrode 30 may also have transparency in the wavelength region of light irradiated to the magnetic element 10. For example, the first electrode 20 and the second electrode 30 are transparent electrodes made of transparent electrode materials containing oxides such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), and indium gallium zinc oxide (IGZO). In addition, the first electrode 20 and the second electrode 30 may also be configured to have a plurality of columnar metals in these transparent electrode materials.

[0060] The insulating layer 50 is located between the first electrode 20 and the second electrode 30. The insulating layer 50 covers, for example, the portion of the magnetic element 10 except for the side surface 10s irradiated with the light L. The insulating layer 50 is an interlayer insulating film. The insulating layer 50 is, for example, an oxide, nitride, or oxynitride of Si, Al, or Mg. The insulating layer 50 is, for example, silicon oxide (SiO x ), Silicon Nitride (SiN x ), silicon carbide (SiC), chromium nitride, silicon carbonitride (SiCN), silicon oxynitride (SiON), aluminum oxide (Al2O3), zirconium oxide (ZrO x )wait.

[0061] When the state of the irradiated light L changes, the resistance value in the z direction of the magnetic element 10 changes according to the change in the state of the light L. When the state of the light L irradiated to each magnetic element 10 changes, the output voltage from the magnetic element 10 changes in accordance with the change in the state of the light L. The magnetic element 10 has, for example, a first ferromagnetic layer 1, a second ferromagnetic layer 2, and a spacer layer 3. The spacer layer 3 is located between the first ferromagnetic layer 1 and the second ferromagnetic layer 2. The magnetic element 10 may have other layers in addition to these.

[0062] A portion of the side surface of the magnetic element 10 is irradiated with light. For example, the side surface 10s is irradiated with light. The side surface 10s is a side surface of the side surface of the magnetic element 10 that is mainly irradiated with light L. The intensity of light irradiated to the side surface 10s is greater than the intensity of light irradiated to other side surfaces. The side surface 10s is, for example, a light-receiving surface of the light L.

[0063] A part of the side surface of the magnetic element 10 is a flat surface. For example, the side surface 10s is a flat surface. For example, the light L is irradiated to the side surface 10s which is a flat surface.

[0064] The side surface of the magnetic element 10 and the side surface of at least one of the first electrode 20 and the second electrode 30 are at least partially in contact with the same virtual plane VS. The virtual plane VS is one of the tangent planes to the side surface of the magnetic element 10. The light L is irradiated to the first ferromagnetic layer 1 from the virtual plane VS side.

[0065] For example, the side surface 10s, the side surface 20s of the first electrode 20, and the side surface 30s of the second electrode 30 are in contact with the same imaginary plane VS. The side surface 10s is continuous with the side surface 20s and the side surface 30s. The side surface 20s is the side surface of the side surface of the first electrode 20 that is mainly irradiated by the light L. The side surface 30s is the side surface of the side surface of the second electrode 30 that is mainly irradiated by the light L.

[0066] The magnetic element 10 is, for example, an MTJ (Magnetic Tunnel Junction) element in which the spacer layer 3 is made of an insulating material. In this case, the resistance value in the z direction (the resistance value when a current flows in the z direction) of the magnetic element 10 changes in accordance with the relative change of the magnetization state of the first ferromagnetic layer 1 and the magnetization state of the second ferromagnetic layer 2. Such an element is also called a magnetoresistance effect element.

[0067] The first ferromagnetic layer 1 is a light detection layer whose magnetization state changes when light is irradiated from the outside. The first ferromagnetic layer 1 is also called a magnetization free layer. The magnetization free layer is a layer containing a magnetic body whose magnetization state changes when a predetermined external force is applied. The predetermined external force is, for example, light L irradiated from the outside, a current flowing in the z direction of the magnetic element 10, and an external magnetic field. The magnetization state of the first ferromagnetic layer 1 changes in accordance with the intensity of the light L irradiated to the first ferromagnetic layer 1.

[0068] The first ferromagnetic layer 1 includes a ferromagnetic body. The first ferromagnetic layer 1 includes at least one of magnetic elements such as Co, Fe or Ni. The first ferromagnetic layer 1 may also include non-magnetic elements such as B, Mg, Hf, Gd, etc. together with the magnetic elements as described above. The first ferromagnetic layer 1 may also be, for example, an alloy including a magnetic element and a non-magnetic element. The first ferromagnetic layer 1 may also be composed of a plurality of layers. The first ferromagnetic layer 1 may be, for example, a CoFeB alloy, a laminated body of a CoFeB alloy layer sandwiched by Fe layers, or a laminated body of a CoFeB alloy layer sandwiched by CoFe layers.

[0069] The first ferromagnetic layer 1 may be an in-plane magnetization film having an easy magnetization axis in the film plane direction (in any direction in the xy plane) or a perpendicular magnetization film having an easy magnetization axis in the film perpendicular direction (z direction).

[0070] The film thickness of the first ferromagnetic layer 1 is, for example, not less than 1 nm and not more than 5 nm. The film thickness of the first ferromagnetic layer 1 is, for example, preferably not less than 1 nm and not more than 2 nm. In the case where the first ferromagnetic layer 1 is a perpendicular magnetization film, if the film thickness of the first ferromagnetic layer 1 is thin, the effect of applying the perpendicular magnetic anisotropy from the layers located above and below the first ferromagnetic layer 1 is enhanced, and the perpendicular magnetic anisotropy of the first ferromagnetic layer 1 is improved. That is, if the perpendicular magnetic anisotropy of the first ferromagnetic layer 1 is high, the force of the magnetization M1 to return to the z direction is enhanced. On the other hand, if the film thickness of the first ferromagnetic layer 1 is thick, the effect of applying the perpendicular magnetic anisotropy from the layers located above and below the first ferromagnetic layer 1 is relatively weakened, and the perpendicular magnetic anisotropy of the first ferromagnetic layer 1 is weakened.

[0071] If the film thickness of the first ferromagnetic layer 1 is reduced, the volume of the ferromagnetic body becomes smaller, and if it is increased, the volume of the ferromagnetic body becomes larger. The ease of magnetization reaction of the first ferromagnetic layer 1 when external energy is applied is inversely proportional to the product (KuV) of the magnetic anisotropy (Ku) and the volume (V) of the first ferromagnetic layer 1. That is, if the product of the magnetic anisotropy and the volume of the first ferromagnetic layer 1 becomes smaller, the reactivity to light increases. From this point of view, in order to improve the reactivity to light, it is preferable to reduce the volume of the first ferromagnetic layer 1 on the basis of appropriately designing the magnetic anisotropy of the first ferromagnetic layer 1.

[0072] When the thickness of the first ferromagnetic layer 1 is thicker than 2 nm, an insertion layer composed of, for example, Mo or W may be provided in the first ferromagnetic layer 1. That is, a laminated body in which a ferromagnetic layer, an insertion layer, and a ferromagnetic layer are sequentially stacked in the z direction may be used as the first ferromagnetic layer 1. The interfacial magnetic anisotropy at the interface between the insertion layer and the ferromagnetic layer improves the perpendicular magnetic anisotropy of the entire first ferromagnetic layer 1. The thickness of the insertion layer is, for example, 0.1 nm to 0.6 nm.

[0073] The second ferromagnetic layer 2 is a magnetization fixed layer. The magnetization fixed layer is a layer composed of a magnetic body whose magnetization state is less likely to change than the magnetization free layer when a predetermined external energy is applied. For example, the magnetization direction of the magnetization fixed layer is less likely to change than the magnetization free layer when a predetermined external energy is applied. In addition, for example, the magnetization size of the magnetization fixed layer is less likely to change than the magnetization free layer when a predetermined external energy is applied. The coercive force of the second ferromagnetic layer 2 is, for example, greater than the coercive force of the first ferromagnetic layer 1. The second ferromagnetic layer 2 has an easy magnetization axis in the same direction as the first ferromagnetic layer 1, for example. The second ferromagnetic layer 2 can be an in-plane magnetization film or a perpendicular magnetization film.

[0074] The material constituting the second ferromagnetic layer 2 is, for example, the same as that of the first ferromagnetic layer 1. The second ferromagnetic layer 2 may be, for example, a stacked body in which Co with a thickness of 0.4 nm to 1.0 nm, Mo with a thickness of 0.1 nm to 0.5 nm, CoFeB alloy with a thickness of 0.3 nm to 1.0 nm, and Fe with a thickness of 0.3 nm to 1.0 nm are stacked in this order.

[0075] The magnetization of the second ferromagnetic layer 2 may be fixed by magnetic coupling with the third ferromagnetic layer via a magnetic coupling layer, for example. In this case, the combination of the second ferromagnetic layer 2, the magnetic coupling layer, and the third ferromagnetic layer may also be referred to as a magnetization fixed layer.

[0076] The third ferromagnetic layer is, for example, magnetically coupled to the second ferromagnetic layer 2. The magnetic coupling is, for example, antiferromagnetic coupling and occurs through RKKY interaction. The material constituting the third ferromagnetic layer is, for example, the same as that of the first ferromagnetic layer 1. The magnetic coupling layer is, for example, Ru, Ir, or the like.

[0077] The spacer layer 3 is a non-magnetic layer disposed between the first ferromagnetic layer 1 and the second ferromagnetic layer 2. The spacer layer 3 is composed of a layer composed of a conductor, an insulator or a semiconductor, or a layer containing a conducting point composed of a conductor in an insulator. The film thickness of the spacer layer 3 can be adjusted according to the orientation direction of the magnetization of the first ferromagnetic layer 1 and the magnetization of the second ferromagnetic layer 2 in the initial state described later.

[0078] For example, when the spacer layer 3 is composed of an insulator, the magnetic element 10 has a magnetic tunnel junction (MTJ: Magnetic Tunnel Junction) composed of the first ferromagnetic layer 1, the spacer layer 3 and the second ferromagnetic layer 2. This element is called an MTJ element. In this case, the magnetic element 10 can exhibit a tunnel magnetoresistance (TMR: Tunnel Magnetoresistance) effect. When the spacer layer 3 is composed of a metal, the magnetic element 10 can exhibit a giant magnetoresistance (GMR: Giant Magnetoresistance) effect. This element is called a GMR element. Depending on the constituent material of the spacer layer 3, the magnetic element 10 is sometimes called a different name from an MTJ element, a GMR element, etc., and is also generally referred to as a magnetoresistance effect element.

[0079] When the spacer layer 3 is made of an insulating material, a material containing aluminum oxide, magnesium oxide, titanium oxide or silicon oxide can be used. In addition, these insulating materials may also contain elements such as Al, B, Si, Mg, and magnetic elements such as Co, Fe, and Ni. By adjusting the film thickness of the spacer layer 3 so that a high TMR effect is exhibited between the first ferromagnetic layer 1 and the second ferromagnetic layer 2, a high magnetoresistance change rate can be obtained. In order to effectively utilize the TMR effect, the film thickness of the spacer layer 3 can be about 0.5 to 5.0 nm, or about 1.0 to 2.5 nm.

[0080] When the spacer layer 3 is formed of a non-magnetic conductive material, conductive materials such as Cu, Ag, Au, or Ru can be used. In order to effectively utilize the GMR effect, the film thickness of the spacer layer 3 may be about 0.5 to 5.0 nm, or about 2.0 to 3.0 nm.

[0081] When the spacer layer 3 is formed of a non-magnetic semiconductor material, materials such as zinc oxide, indium oxide, tin oxide, germanium oxide, gallium oxide, or ITO can be used. In this case, the film thickness of the spacer layer 3 can be about 1.0 to 4.0 nm.

[0082] When a layer including a conducting point composed of a conductor in a non-magnetic insulator is used as the spacer layer 3, a structure in which a conducting point composed of a non-magnetic conductor such as Cu, Au, or Al is included in a non-magnetic insulator composed of aluminum oxide or magnesium oxide can also be used. In addition, the conductor can also be composed of a magnetic element such as Co, Fe, or Ni. In this case, the film thickness of the spacer layer 3 can be about 1.0 to 2.5 nm. The conducting point is, for example, a columnar body with a diameter of more than 1 nm and less than 5 nm when observed from a direction perpendicular to the film surface.

[0083] In addition, the magnetic element 10 may also have a base layer, a cover layer, a perpendicular magnetization inducing layer, etc. The base layer is located between the second ferromagnetic layer 2 and the second electrode 30. The base layer is a seed layer or a buffer layer. The seed layer improves the crystallinity of the layer stacked on the seed layer. The seed layer is, for example, Pt, Ru, Hf, Zr, NiFeCr. The film thickness of the seed layer is, for example, greater than 1 nm and less than 5 nm. The buffer layer is a layer that alleviates the lattice mismatch between different crystals. The buffer layer is, for example, Ta, Ti, W, Zr, Hf or nitrides of these elements. The film thickness of the buffer layer is, for example, greater than 1 nm and less than 5 nm.

[0084] The cap layer is located between the first ferromagnetic layer 1 and the first electrode 20. The cap layer prevents damage to the lower layer during the process and improves the crystallinity of the lower layer during annealing. The film thickness of the cap layer is, for example, 3 nm or less so that sufficient light is irradiated to the first ferromagnetic layer 1. The cap layer is, for example, MgO, W, Mo, Ru, Ta, Cu, Cr, or a laminated film thereof.

[0085] The perpendicular magnetization inducing layer is formed when the first ferromagnetic layer 1 is a perpendicular magnetization film. The perpendicular magnetization inducing layer is stacked on the first ferromagnetic layer 1. The perpendicular magnetization inducing layer induces perpendicular magnetic anisotropy of the first ferromagnetic layer 1. The perpendicular magnetization inducing layer is, for example, magnesium oxide, W, Ta, Mo, etc. When the perpendicular magnetization inducing layer is magnesium oxide, magnesium oxide is preferably oxygen-deficient in order to improve conductivity. The film thickness of the perpendicular magnetization inducing layer is, for example, not less than 0.5 nm and not more than 2.0 nm.

[0086] The light detection element 100 is manufactured through a lamination process, an annealing process, and a processing process of each layer. First, the second electrode 30, the second ferromagnetic layer 2, the spacer layer 3, and the first ferromagnetic layer 1 are sequentially laminated on a substrate. Each layer is formed by, for example, sputtering.

[0087] Next, the laminated film is annealed. The annealing temperature is, for example, 250°C to 450°C. When the substrate is a circuit substrate, the annealing is preferably performed at 400°C or above. Then, the laminated film is processed into a predetermined columnar body by photolithography and etching. The columnar body may be a cylinder or a prism. For example, the shortest width of the columnar body when observed from the z direction may be greater than 10 nm and less than 2000 nm, or may be greater than 30 nm and less than 500 nm.

[0088] Next, the insulating layer 50 is formed to cover the side surfaces of the columnar bodies. The insulating layer 50 may be stacked multiple times. Next, the upper surface of the first ferromagnetic layer 1 is exposed from the insulating layer 50 by chemical mechanical polishing (CMP), and the first electrode 20 is formed on the first ferromagnetic layer 1 .

[0089] Next, the substrate and the insulating layer 50 are cut. Then, the insulating layer 50 is removed by subjecting the cut surface to chemical mechanical polishing (CMP) and ion beam etching, for example, to expose the second electrode 30, the second ferromagnetic layer 2, the spacer layer 3, and the first ferromagnetic layer 1 from the insulating layer 50. Thus, the side surface 10s becomes a flat surface, and the side surface 30s, the side surface 10s, and the side surface 20s are continuous. Finally, by arranging the light irradiation unit 40 at a position opposite to the side surface 10s, the light detection element 100 is obtained.

[0090] Next, several examples of the operation of the light detection element 100 are described. Light of varying intensity is irradiated onto the first ferromagnetic layer 1. The output voltage from the light detection element 100 changes due to the irradiation of the light onto the first ferromagnetic layer 1. In the first operation example, the case where the intensity of the light irradiated onto the first ferromagnetic layer 1 is at two levels, namely, the first intensity and the second intensity is described as an example. The intensity of the light of the second intensity is greater than the intensity of the light of the first intensity. The first intensity may also be the case where the intensity of the light irradiated onto the first ferromagnetic layer 1 is zero.

[0091] Figure 4 and Figure 5 It is a diagram for explaining a first operation example of the photodetection element 100 according to the first embodiment. Figure 4 is a diagram for explaining the first mechanism of the first operation example. Figure 5 This is a diagram for explaining the second mechanism of the first operation example. Figure 4 and Figure 5 In the figure above, the vertical axis is the intensity of light irradiating the first ferromagnetic layer 1, and the horizontal axis is time. Figure 4 and Figure 5 In the figure below, the vertical axis is the resistance value of the magnetic element 10 in the z direction, and the horizontal axis is time.

[0092] First, in a state where the first ferromagnetic layer 1 is irradiated with light of the first intensity (hereinafter referred to as the initial state), the magnetization M1 of the first ferromagnetic layer 1 and the magnetization M2 of the second ferromagnetic layer 2 are in a parallel relationship, the resistance value of the magnetic element 10 in the z direction shows the first resistance value R1, and the magnitude of the output voltage from the magnetic element 10 shows the first value. The resistance value of the magnetic element 10 in the z direction is generated by the sensing current Is flowing in the z direction of the magnetic element 10, and the voltage is generated at both ends of the magnetic element 10 in the z direction, so Ohm's law is used to calculate the voltage value. The output voltage from the magnetic element 10 is generated between the first electrode 20 and the second electrode 30. Figure 4 In the example shown, the sense current Is is caused to flow from the first ferromagnetic layer 1 to the second ferromagnetic layer 2. By causing the sense current Is to flow in this direction, a spin transfer torque in the same direction as the magnetization M2 of the second ferromagnetic layer 2 acts on the magnetization M1 of the first ferromagnetic layer 1, and the magnetization M1 is parallel to the magnetization M2 in the initial state. In addition, by causing the sense current Is to flow in this direction, it is possible to prevent the magnetization M1 of the first ferromagnetic layer 1 from being reversed during operation.

[0093] Next, the intensity of the light irradiated to the first ferromagnetic layer 1 is changed from the first intensity to the second intensity. The second intensity is greater than the first intensity, and the magnetization M1 of the first ferromagnetic layer 1 changes from the initial state. The state of the magnetization M1 of the first ferromagnetic layer 1 in the state where the first ferromagnetic layer 1 is not irradiated with light is different from the state of the magnetization M1 of the first ferromagnetic layer 1 at the second intensity. The state of the magnetization M1 is, for example, the tilt angle with respect to the z direction, the size, etc.

[0094] For example, Figure 4 As shown in FIG. 1 , when the intensity of the light irradiating the first ferromagnetic layer 1 changes from the first intensity to the second intensity, the magnetization M1 is inclined with respect to the z direction. Figure 5As shown, when the intensity of light irradiating the first ferromagnetic layer 1 changes from the first intensity to the second intensity, the magnitude of the magnetization M1 decreases. For example, when the magnetization M1 of the first ferromagnetic layer 1 is tilted relative to the z direction due to the intensity of light irradiation, the tilt angle is greater than 0° and less than 90°.

[0095] When the magnetization M1 of the first ferromagnetic layer 1 changes from the initial state, the resistance value in the z direction of the magnetoresistive element 10 shows a second resistance value R2, and the magnitude of the output voltage from the magnetic element 10 shows a second value. The second resistance value R2 is greater than the first resistance value R1, and the second value of the output voltage is also greater than the first value. The second resistance value R2 is between the resistance value (first resistance value R1) when the magnetization M1 and the magnetization M2 are parallel and the resistance value when the magnetization M1 and the magnetization M2 are antiparallel.

[0096] exist Figure 4 In the case shown, the magnetization M1 of the first ferromagnetic layer 1 has a spin transfer torque in the same direction as the magnetization M2 of the second ferromagnetic layer 2. Therefore, the magnetization M1 wants to return to a state parallel to the magnetization M2. If the intensity of the light irradiating the first ferromagnetic layer 1 changes from the second intensity to the first intensity, the magnetic element 10 returns to the initial state. Figure 5 In the case shown, if the intensity of the light irradiated to the first ferromagnetic layer 1 returns to the first intensity, the magnitude of the magnetization M1 of the first ferromagnetic layer 1 is restored, and the magnetic element 10 returns to the initial state. In either case, when the resistance value in the z direction of the magnetic element 10 returns to the first resistance value R1. That is, when the intensity of the light irradiated to the first ferromagnetic layer 1 changes from the second intensity to the first intensity, the resistance value in the z direction of the light detection element 100 changes from the second resistance value R2 to the first resistance value R1, and the magnitude of the output voltage from the magnetic element 10 changes from the second value to the first value.

[0097] The output voltage from the light detection element 100 changes in accordance with the change in the intensity of the light irradiated to the first ferromagnetic layer 1, and the change in the intensity of the irradiated light can be converted into a change in the output voltage from the light detection element 100. That is, the light detection element 100 can replace light with an electrical signal. For example, the output voltage from the light detection element 100 is processed as a first signal (e.g., "1") when it is above a threshold value, and as a second signal (e.g., "0") when it is below the threshold value.

[0098] Here, the case where the magnetization M1 and the magnetization M2 are parallel in the initial state is described as an example, but the magnetization M1 and the magnetization M2 may also be antiparallel in the initial state. In this case, the more the state of the magnetization M1 changes (for example, the greater the angle change of the magnetization M1 from the initial state), the smaller the resistance value of the magnetic element 10 in the z direction. When the case where the magnetization M1 and the magnetization M2 are antiparallel is set as the initial state, it is preferred that the sense current Is flows from the second ferromagnetic layer 2 to the first ferromagnetic layer 1. By making the sense current Is flow in this direction, a spin transfer torque in the opposite direction to the magnetization M2 of the second ferromagnetic layer 2 acts on the magnetization M1 of the first ferromagnetic layer 1, and the magnetization M1 and the magnetization M2 become antiparallel in the initial state.

[0099] In the first operation example, the case where the light irradiating the first ferromagnetic layer 1 has two levels of intensity, the first intensity and the second intensity, is described as an example. However, in the second operation example, the case where the intensity of the light irradiating the first ferromagnetic layer 1 changes in multiple levels or in a simulated manner is described.

[0100] Figure 6 and Figure 7 It is a diagram for explaining a second operation example of the photodetection element 100 according to the first embodiment. Figure 6 is a diagram for explaining the first mechanism of the first operation example. Figure 7 This is a diagram for explaining the second mechanism of the first operation example. Figure 6 and Figure 7 In the figure above, the vertical axis is the intensity of light irradiating the first ferromagnetic layer 1, and the horizontal axis is time. Figure 6 and Figure 7 In the figure below, the vertical axis is the resistance value of the magnetic element 10 in the z direction, and the horizontal axis is time.

[0101] exist Figure 6 In the case where the intensity of light irradiating the first ferromagnetic layer 1 increases, the magnetization M1 of the first ferromagnetic layer 1 tilts from the initial state due to the energy from the outside generated by the irradiation of light. The angle between the direction of the magnetization M1 of the first ferromagnetic layer 1 in a state where the first ferromagnetic layer 1 is not irradiated with light and the direction of the magnetization M1 in a state where the first ferromagnetic layer 1 is irradiated with light is greater than 0° and less than 90°.

[0102] If the magnetization M1 of the first ferromagnetic layer 1 is tilted from the initial state, the resistance value of the magnetoresistive element 10 in the z direction changes. Moreover, the output voltage from the magnetic element 10 changes. For example, in accordance with the tilt of the magnetization M1 of the first ferromagnetic layer 1, the resistance value of the magnetic element 10 in the z direction changes to the second resistance value R2, the third resistance value R3, and the fourth resistance value R4, and the output voltage from the magnetic element 10 changes between the second value, the third value, and the fourth value. The resistance value increases in the order of the first resistance value R1, the second resistance value R2, the third resistance value R3, and the fourth resistance value R4. The output voltage from the magnetic element 10 increases in the order of the first value, the second value, the third value, and the fourth value.

[0103] When the intensity of light irradiated to the first ferromagnetic layer 1 of the magnetic element 10 changes, the output voltage from the magnetic element 10 (the resistance value of the magnetic element 10 in the z direction) changes. For example, if the first value (the first resistance value R1) is set to "0", the second value (the second resistance value R2) is set to "1", the third value (the third resistance value R3) is set to "2", and the fourth value (the fourth resistance value R4) is set to "3", the light detection element 100 can output information of four values. Here, as an example, the case of reading out four values ​​is shown, but by setting the threshold value of the output voltage from the magnetic element 10 (the resistance value of the magnetic element 10), the number of values ​​to be read can be freely designed. In addition, the light detection element 100 can also directly output analog values.

[0104] In addition, Figure 7 Similarly, in the case of , if the intensity of light irradiating the first ferromagnetic layer 1 increases, the magnetization M1 of the first ferromagnetic layer 1 decreases from the initial state due to the energy from the outside generated by the irradiation of light. If the magnetization M1 of the first ferromagnetic layer 1 decreases from the initial state, the resistance value in the z direction of the magnetoresistance effect element 10 changes. Moreover, the output voltage from the magnetic element 10 changes. For example, corresponding to the size of the magnetization M1 of the first ferromagnetic layer 1, the resistance value in the z direction of the magnetic element 10 changes to the second resistance value R2, the third resistance value R3, and the fourth resistance value R4, and the output voltage from the magnetic element 10 changes between the second value, the third value, and the fourth value. Therefore, Figure 6 Similarly to the case of , the light detection element 100 can output the difference in output voltage (resistance value) from these as multi-valued or analog data.

[0105] In the second operation example, similarly to the first operation example, when the intensity of the light irradiating the first ferromagnetic layer 1 returns to the first intensity, the state of the magnetization M1 of the first ferromagnetic layer 1 is restored and the magnetic element 10 returns to the initial state.

[0106] Here, the case where the magnetization M1 and the magnetization M2 are parallel in the initial state is described as an example, but in the second operation example as well, the magnetization M1 and the magnetization M2 may be antiparallel in the initial state.

[0107] In addition, in the first and second operation examples, the case where the magnetization M1 and the magnetization M2 are parallel or antiparallel in the initial state is exemplified, but the magnetization M1 and the magnetization M2 may be orthogonal in the initial state. For example, the case where the first ferromagnetic layer 1 is an in-plane magnetization film in which the magnetization M1 is oriented in any direction in the xy plane and the second ferromagnetic layer 2 is a perpendicular magnetization film in which the magnetization M2 is oriented in the z direction corresponds to this case. Due to magnetic anisotropy, the magnetization M1 is oriented in any direction in the xy plane and the magnetization M2 is oriented in the z direction, so that the magnetization M1 and the magnetization M2 are orthogonal in the initial state.

[0108] Figure 8 and Fig. 9 FIG. 2 is a diagram for explaining another example of the second operation example of the light detection element 100 according to the first embodiment. Figure 8 and Fig. 9 In the embodiment, the flow direction of the sensing current Is applied to the magnetic element 10 is different. Figure 8 , so that the sense current Is flows from the first ferromagnetic layer 1 to the second ferromagnetic layer 2 . Fig. 9 , so that the sense current Is flows from the second ferromagnetic layer 2 to the first ferromagnetic layer 1 .

[0109] exist Figure 8 and Fig. 9 In any case, by passing the sense current Is through the magnetic element 10, a spin transfer torque acts on the magnetization M1 in the initial state. Figure 8 In the case of , the spin transfer torque acts in a manner that the magnetization M1 is parallel to the magnetization M2 of the second ferromagnetic layer 2. Fig. 9 In the case of , the spin transfer torque acts in a manner that the magnetization M1 is antiparallel to the magnetization M2 of the second ferromagnetic layer 2. Figure 8 and Fig. 9 In any case, in the initial state, the effect of magnetic anisotropy on magnetization M1 is greater than the effect of spin transfer torque, so magnetization M1 is oriented in any direction in the xy plane.

[0110] If the intensity of light irradiating the first ferromagnetic layer 1 increases, the magnetization M1 of the first ferromagnetic layer 1 tilts from the initial state due to the external energy generated by the irradiation of light. This is because the sum of the effect of the irradiation of light and the effect of the spin transfer torque applied to the magnetization M1 is greater than the effect of the magnetic anisotropy of the magnetization M1. If the intensity of light irradiating the first ferromagnetic layer 1 increases, Figure 8In the case of , the magnetization M1 is tilted in parallel with the magnetization M2 of the second ferromagnetic layer 2. Fig. 9 In the case of , the magnetization M1 is tilted in an antiparallel manner to the magnetization M2 of the second ferromagnetic layer 2. The directions of the spin transfer torque acting on the magnetization M1 are different, so Figure 8 and Fig. 9 The tilt direction of the magnetization M1 is different.

[0111] If the intensity of the light irradiating the first ferromagnetic layer 1 increases, Figure 8 In the case of , the resistance value of the magnetic element 10 becomes smaller, and the output voltage from the magnetic element 10 becomes smaller. Fig. 9 In the case of , the resistance value of the magnetic element 10 increases, and the output voltage from the magnetic element 10 increases.

[0112] When the intensity of the light irradiating the first ferromagnetic layer 1 returns to the first intensity, the state of the magnetization M1 of the first ferromagnetic layer 1 returns to the original state due to the action of magnetic anisotropy on the magnetization M1. As a result, the magnetic element 10 returns to the initial state.

[0113] Here, an example is given in which the first ferromagnetic layer 1 is an in-plane magnetization film and the second ferromagnetic layer 2 is a perpendicular magnetization film, but the relationship may be reversed. That is, in the initial state, the magnetization M1 may be oriented in the z direction and the magnetization M2 may be oriented in any direction in the xy plane.

[0114] As described above, the light detection element 100 according to the first embodiment can replace light irradiated to the magnetic element 10 with an output voltage from the magnetic element 10 , thereby replacing light with an electric signal.

[0115] In addition, the light L is irradiated from the side surface 10s toward the magnetic element 10. That is, the light L is also easily irradiated to the portion of the first ferromagnetic layer 1 on the side of the spacer layer 3. The change in the magnetization state of the portion of the first ferromagnetic layer 1 on the side of the spacer layer 3 greatly contributes to the change in the output voltage from the magnetic element 10 (the change in the resistance value of the magnetic element 10 in the z direction). As a result, the responsiveness of the change in the output voltage from the magnetic element 10 (the change in the resistance value of the magnetic element 10) to the change in the state of the light L is high.

[0116] As mentioned above, although 1st Embodiment was described in detail with reference to drawings, 1st Embodiment is not limited to this example.

[0117] For example, Fig.10As shown in the light detecting element 101, the side surface 11s of the magnetic element 11 may be inclined relative to the z direction. The side surface 11s is continuous with the side surface 21s of the first electrode 21 and the side surface 31s of the second electrode 31. The side surface 11s is a flat surface. The light detecting element 101 of the first modified example also easily irradiates light to the portion on the spacer layer side of the first ferromagnetic layer 1, so it has the same effect as the light detecting element 100.

[0118] In addition, if Fig.11 The light detection element 102 and Fig.12 As in the illustrated light detecting element 103 , the shape of the magnetic elements 12 , 13 when viewed from the z direction may be a shape other than a rectangle.

[0119] Fig.11 The shape of the magnetic element 12 shown as viewed from the z direction is circular. A portion of the side surface 12s of the magnetic element 12, the side surface 20s of the first electrode 20, and the side surface 30s of the second electrode 30 are in contact with the same imaginary plane VS. The side surface 12s is in contact with the imaginary plane VS at its linear portion extending in the z direction. The portion of the side surface 12s in contact with the imaginary plane VS is continuous with the side surface 20s and the side surface 30s.

[0120] Fig.12 The shape of the magnetic element 13 shown as viewed from the z direction is a missing circle in which a part of a circle is missing. The side surface of the magnetic element 13 is composed of a side surface 13s which is a flat surface and a side surface which is an arc shape when viewed from the z direction. The side surface 13s, the side surface 20s and the side surface 30s are connected to the same imaginary plane VS. The side surface 13s is continuous with the side surface 20s and the side surface 30s.

[0121] In addition, if Fig.13 As with the photodetection element 104 shown in the figure, the shapes of the first electrode 22 and the second electrode 32 viewed from the z direction may be shapes other than rectangles.

[0122] Fig.13 The shape of the magnetic element 12 shown when viewed from the z direction is circular. Fig.13 The shape of the first electrode 22 and the second electrode 32 shown as viewed from the z direction is an ellipse. A portion of the side 12s of the magnetic element 12, a portion of the side 22s of the first electrode 22, and a portion of the side 32s of the second electrode 32 are in contact with the same imaginary plane VS. The side 12s is in contact with the imaginary plane VS at a linear portion extending along the z direction. The side 22s is in contact with the imaginary plane VS at a linear portion extending along the z direction. The side 32s is in contact with the imaginary plane VS at a linear portion extending along the z direction. The portion of the side 12s in contact with the imaginary plane VS is continuous with the portions of the side 22s and the side 32s in contact with the imaginary plane VS.

[0123] In addition, the examples in which a part of the side surface of both the first electrode and the second electrode and a part of the side surface of the magnetic element are in contact with the same imaginary plane VS are illustrated so far, but the present invention is not limited to this case. For example, only a part of the side surface of one of the first electrode and the second electrode and a part of the side surface of the magnetic element may be in contact with the same imaginary plane VS.

[0124] (Second embodiment)

[0125] Fig.14 yz cross-sectional view of the light detecting element 105 of the second embodiment. The light detecting element 105 differs from the light detecting element 100 of the first embodiment in that it includes an oxide film 60. In the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals and their description is omitted.

[0126] The oxide film 60 covers the flat surface consisting of the side surface 10s, the side surface 20s, and the side surface 30s. Fig.14 , an example is shown in which the oxide film 60 covers the entire flat surface composed of the side surface 10s, the side surface 20s, and the side surface 30s, but the structure may also cover only a portion. For example, the oxide film 60 may also be a structure that covers only the side surface 10s of the magnetic element 10.

[0127] The oxide film 60 has a transmittance in the wavelength region of the light irradiated to the magnetic element 10. The oxide film 60 is, for example, an insulating oxide. The oxide film 60 is, for example, silicon oxide, aluminum oxide, etc. The oxide film 60 protects the side surface 10s of the magnetic element 10 from corrosion, wear, etc.

[0128] The light detecting element 105 of the second embodiment achieves the same effects as those of the light detecting element 100. In addition, the light detecting element 105 has excellent weather resistance due to the presence of the oxide film 60.

[0129] (Third embodiment)

[0130] Fig.15 yz cross-sectional view of the light detection element 106 of the third embodiment. The light detection element 106 differs from the light detection element 100 of the first embodiment in that it has a heat generating portion 70. In the third embodiment, the same components as those of the first embodiment are denoted by the same reference numerals and their description is omitted.

[0131] The heating portion 70 is located at a position capable of heating the first ferromagnetic layer 1. The heating portion 70 is located, for example, behind the magnetic element 10 in the direction of light irradiation to the magnetic element 10. The heating portion 70 may not overlap with the magnetic element 10 when viewed from the light irradiation direction. The heating portion 70 is located on the side of the magnetic element 10 opposite to the surface of the magnetic element 10 that is mainly irradiated with the light L.

[0132] The heat generating unit 70 is, for example, a coil. The heat generating unit 70 is, for example, a resistor made of Cu, a nickel-chromium alloy, an iron-chromium-aluminum alloy, etc. When a current flows through the resistor, the heat generating unit 70 generates heat.

[0133] When the heat generating portion 70 generates heat, the first ferromagnetic layer 1 is heated. The heated first ferromagnetic layer 1 expands. When the first ferromagnetic layer 1 expands, the side surface of the first ferromagnetic layer 1 protrudes from the virtual plane connecting the side surface 20s and the side surface 30s.

[0134] The light detecting element 106 of the third embodiment has the same effect as the light detecting element 100. In addition, the side surface of the first ferromagnetic layer 1 can be made to protrude from the imaginary plane connecting the side surface 20s and the side surface 30s by the heat generated by the heat generating portion 70, and the distance between the side surface of the first ferromagnetic layer 1 and the light irradiation portion 40 can be changed. As a result, the intensity of the light irradiated to the first ferromagnetic layer 1 can be adjusted without changing the irradiation intensity from the light irradiation portion 40.

[0135] (Fourth embodiment)

[0136] Fig.16 yz cross-sectional view of the light detecting element 107 of the fourth embodiment. The light detecting element 107 differs from the light detecting element 100 of the first embodiment in that it has a heat generating portion 70 and an expansion portion 80. In the third embodiment, the same reference numerals are used for the same structures as those of the first embodiment, and description thereof is omitted.

[0137] The heating portion 70 is located at a position capable of heating the expansion portion 80. The heating portion 70 is located, for example, behind the magnetic element 10 in the direction of light irradiation to the magnetic element 10. The heating portion 70 may not overlap with the magnetic element 10 when viewed from the light irradiation direction. The heating portion 70 is located on the side of the magnetic element 10 opposite to the surface of the magnetic element 10 that is mainly irradiated with the light L.

[0138] The expansion portion 80 is located behind the magnetic element 10 in the direction of light irradiation to the magnetic element 10, for example. The expansion portion 80 may not overlap with the magnetic element 10 when viewed from the light irradiation direction. The expansion portion 80 is located on the opposite side of the surface of the magnetic element 10 that is mainly irradiated with the light L, across the magnetic element 10. The expansion portion 80 is heated and expanded when the heating portion 70 generates heat. The expansion portion 80 is located at a position where the first ferromagnetic layer 1 can be squeezed out.

[0139] The expansion portion 80 is made of a material having a larger linear thermal expansion coefficient than the first ferromagnetic layer 1. The expansion portion 80 is made of, for example, aluminum, magnesium, zinc, tin, or an alloy containing these.

[0140] When the heat generating portion 70 generates heat, the expansion portion 80 is heated. When the heated expansion portion 80 expands, the first ferromagnetic layer 1 is pushed outward. As a result, the side surface of the first ferromagnetic layer 1 protrudes from the virtual surface connecting the side surface 20s and the side surface 30s.

[0141] The light detecting element 107 of the fourth embodiment has the same effect as the light detecting element 100. In addition, the distance between the side surface of the first ferromagnetic layer 1 and the light irradiation portion 40 can be changed by the heat generation of the heat generating portion 70 and the expansion of the expansion portion 80. As a result, the intensity of the light irradiated to the first ferromagnetic layer 1 can be adjusted without changing the irradiation intensity from the light irradiation portion 40.

[0142] As mentioned above, the present invention is not limited to the above-mentioned embodiments and modified examples, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. For example, the characteristic structures of the above-mentioned embodiments and modified examples can be combined respectively.

[0143] The light detection elements of the above-described embodiment and modified examples can be applied to light sensor devices such as image sensors, transmission and reception devices of communication systems, and the like.

[0144] Fig.17 1 is a block diagram of a transmitting and receiving device 1000 according to a first application example. The transmitting and receiving device 1000 includes a receiving device 300 and a transmitting device 400. The receiving device 300 receives an optical signal L1, and the transmitting device 400 transmits an optical signal L2.

[0145] The receiving device 300 includes, for example, a light detecting element 301 and a signal processing unit 302. The light detecting element 301 is any of the light detecting elements 100 to 107 in the above-mentioned embodiments or modified examples. In the receiving device 300, light including a high-frequency light signal L1 and having a varying intensity is irradiated onto the first ferromagnetic layer 1. A lens may be arranged on the first ferromagnetic layer 1 side in the stacking direction of the light detecting element 301 so that the light focused by the lens is irradiated onto the first ferromagnetic layer 1. The lens may be formed in the wafer process of forming the light detecting element 301. In addition, the light passing through the waveguide path may be irradiated onto the first ferromagnetic layer 1 of the light detecting element 301. The light irradiated onto the first ferromagnetic layer 1 of the light detecting element 301 is, for example, laser light. The light detecting element 301 converts the light signal L1 into an electrical signal. The operation of the light detecting element 301 may be any of the first operation example and the second operation example. The signal processing unit 302 processes the electrical signal converted by the light detecting element 301. The signal processing unit 302 receives the signal included in the optical signal L1 by processing the electric signal generated from the photodetection element 301. The receiving device 300 receives the signal included in the optical signal L1 based on the output voltages from the magnetic elements 10 to 13.

[0146] The transmitting device 400 includes, for example, a light source 401, an electric signal generating element 402, and an optical modulator 403. The light source 401 is, for example, a laser element. The light source 401 may also be located outside the transmitting device 400. The electric signal generating element 402 generates an electric signal based on the transmission information. The electric signal generating element 402 may also be integrated with the signal conversion element of the signal processing unit 302. The optical modulator 403 modulates the light output from the light source 401 based on the electric signal generated by the electric signal generating element 402, and outputs an optical signal L2.

[0147] Fig.18 This is a conceptual diagram of an example of a communication system. Fig.18 The communication system shown has two terminal devices 500. The terminal device 500 is, for example, a smartphone, a tablet computer, a personal computer, or the like.

[0148] The terminal devices 500 each include a receiving device 300 and a transmitting device 400. An optical signal transmitted from a transmitting device 400 of one terminal device 500 is received by the receiving device 300 of another terminal device 500. The light used for transmission and reception between the terminal devices 500 is, for example, visible light. The receiving device 300 includes the above-mentioned light detection elements 100 to 107 as light detection elements 301. The above-mentioned light detection elements 100 to 107 have good responsiveness to light, so Fig.18 The reliability of the communication system shown is high.

[0149] Fig.19 This is a conceptual diagram of a cross section of an optical sensor device 2000 according to a second application example. The optical sensor device 2000 includes, for example, a circuit board 110 , a wiring layer 120 , and a plurality of optical sensors S. The wiring layer 120 and the plurality of optical sensors S are formed on the circuit board 110 .

[0150] Each of the plurality of optical sensors S includes, for example, a light detection element 100, a wavelength filter F, and a lens R. Fig.19 , an example using the light detection element 100 is shown, but light detection elements 101 to 107 may be used instead of the light detection element 100. The light that has passed through the wavelength filter F is irradiated to the light detection element 100. As described above, the light detection element 100 replaces the light irradiated to the magnetic element 10 with an electrical signal. The light detection element 100 preferably operates in the second operation example.

[0151] The wavelength filter F selects light of a specific wavelength and transmits light of a specific wavelength region. The wavelength regions of light transmitted through each wavelength filter F may be the same or different. For example, the optical sensor device 2000 may also include: an optical sensor S (hereinafter referred to as a blue sensor) having a wavelength filter F that transmits blue (a wavelength region of 380 nm or more and less than 490 nm); an optical sensor S (hereinafter referred to as a green sensor) having a wavelength filter F that transmits green (a wavelength region of 490 nm or more and less than 590 nm); and an optical sensor S (hereinafter referred to as a red sensor) having a wavelength filter F that transmits red (a wavelength region of 590 nm or more and less than 800 nm). By setting the blue sensor, the green sensor, and the red sensor as one pixel and arranging the pixel, the optical sensor device 2000 can be used as an image sensor.

[0152] The lens R focuses the light toward the magnetic element 10 . Fig.19 Although the optical sensor S shown in the figure has one light detection element 100 disposed below one wavelength filter F, a plurality of light detection elements 100 may be disposed below one wavelength filter F.

[0153] The circuit board 110 includes, for example, an analog-to-digital converter 111 and an output terminal 112 . The electrical signal transmitted from the photosensor S is converted into digital data by the analog-to-digital converter 111 , and is output from the output terminal 112 .

[0154] The wiring layer 120 has a plurality of wirings 121. An interlayer insulating film 122 is provided between the plurality of wirings 121. The wirings 121 electrically connect each of the optical sensors S and the circuit substrate 110, and each of the operation circuits formed on the circuit substrate 110. Each of the optical sensors S and the circuit substrate 110 is connected via a through wiring that penetrates the interlayer insulating film 122 in the z direction, for example. By shortening the distance between the wirings between each of the optical sensors S and the circuit substrate 110, noise can be reduced.

[0155] The wiring 121 is conductive. The wiring 121 is made of, for example, Al, Cu, etc. The interlayer insulating film 122 is an insulator that insulates the wirings and elements of the multilayer wiring. The interlayer insulating film 122 is made of, for example, oxides, nitrides, or oxynitrides of Si, Al, or Mg. The interlayer insulating film 122 is made of, for example, silicon oxide (SiO x ), Silicon Nitride (SiN x ), silicon carbide (SiC), chromium nitride, silicon carbonitride (SiCN), silicon oxynitride (SiON), aluminum oxide (Al2O3), zirconium oxide (ZrO x )wait.

[0156] The above-described optical sensor device 2000 can be used in, for example, a terminal device. Fig. 20It is a schematic diagram of an example of the terminal device 600. Fig. 20 The left side is the surface of the terminal device 600. Fig. 20 The right side of is the back side of the terminal device 600. The terminal device 600 has a camera CA. The above-mentioned optical sensor device 2000 can be used as an imaging element of the camera CA. Fig. 20 In the embodiment of the present invention, a smartphone is illustrated as an example of the terminal device 600, but the present invention is not limited to this case. The terminal device 600 may be, for example, a tablet computer, a personal computer, a digital camera, etc., in addition to a smartphone.

Claims

1. A light detection element, characterized in that: A magnetic element comprising a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic spacer layer sandwiched by the first ferromagnetic layer and the second ferromagnetic layer. The spacer layer is a layer composed of a conductor or an insulator, or a layer containing a current point composed of a conductor in an insulator. It also has: a first electrode and a second electrode, which sandwich the magnetic element in the stacking direction of the magnetic element, The side surface of at least one of the first electrode and the second electrode and the side surface of the magnetic element are in contact with the same imaginary plane at least in part. A portion of the side surface of the magnetic element is a flat surface, The flat surface is in contact with the imaginary plane, The flat surface of the first ferromagnetic layer is irradiated with light from a direction intersecting the stacking direction.

2. The light detecting element according to claim 1, wherein: The invention further comprises an oxide film which covers the flat surface and can transmit the light.

3. The light detection element according to any one of claims 1 to 2, characterized in that: Also has: heating part, The heat generating portion is located behind the magnetic element in the light irradiation direction in which the light is mainly irradiated relative to the magnetic element.

4. The light detecting element according to claim 3, wherein: It also has: an expansion portion, The heat generating portion is located at a position capable of heating the expansion portion. The expansion portion is located behind the magnetic element in the direction of light irradiation relative to the main irradiation of the magnetic element. The expansion portion has a linear thermal expansion coefficient greater than a linear thermal expansion coefficient of the first ferromagnetic layer.

5. The light detection element according to any one of claims 1 to 4, characterized in that: The light includes a high-frequency optical signal and has a varying intensity.

6. The light detection element according to any one of claims 1 to 5, characterized in that: The light is light transmitted through the wavelength filter.

7. A receiving device, characterized in that: A light detecting element according to any one of claims 1 to 6.

8. A light sensor device, characterized in that: A light detecting element according to any one of claims 1 to 4 and claim 6.

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