Light detecting element, receiving device and light sensor device

Abstract

The present invention provides a light detection element, a receiving device and a light sensor device. The light detection element includes: a magnetic element having a first ferromagnetic layer to be irradiated with light, a second ferromagnetic layer and a spacer layer sandwiched by the first ferromagnetic layer and the second ferromagnetic layer; a first electrode and a second electrode, the first electrode being in contact with a first surface on the first ferromagnetic layer side in the stacking direction of the magnetic element, and the second electrode being in contact with a second surface on the opposite side of the first surface; and a first high thermal conductivity layer, which is located outside the first ferromagnetic layer and has a higher thermal conductivity than the first electrode.

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 for various purposes.

[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] Technical problem to be solved by the invention

[0010] Although photodetection elements using semiconductor pn junctions are widely used, new photodetection elements are sought for further development. In addition, photodetection elements often generate heat that adversely affects the elements and circuits when irradiated with light, and it is required to improve heat dissipation.

[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 excellent heat dissipation properties.

[0012] Technical solutions for solving technical problems

[0013] In order to solve the above technical problems, the following technical solutions are provided.

[0014] (1) The light detection element of the first scheme includes: a magnetic element, which has a first ferromagnetic layer irradiated with light, a second ferromagnetic layer and a spacer layer sandwiched by the first ferromagnetic layer and the second ferromagnetic layer; a first electrode and a second electrode, the first electrode is in contact with a first surface on the side of the first ferromagnetic layer in the stacking direction of the magnetic element, and the second electrode is in contact with a second surface on the opposite side of the first surface; a first high thermal conductivity layer, which is located on the outside of the first ferromagnetic layer and has a higher thermal conductivity than the first electrode.

[0015] (2) In the light detection element according to the above aspect, the first electrode may include an oxide having a property of transmitting the light.

[0016] (3) In the light detection element according to the above aspect, the first high thermal conductive layer may be a non-magnetic material.

[0017] (4) In the light detecting element according to the above aspect, the first high thermal conductive layer may be in contact with the first ferromagnetic layer.

[0018] (5) In the light detecting element according to the above aspect, the first high heat conductive layer may be in contact with the first electrode.

[0019] (6) The light detecting element according to the above aspect may further include a second high heat conductive layer in contact with a side wall of the first electrode, and the second high heat conductive layer may have a higher thermal conductivity than the first electrode.

[0020] (7) In the light detecting element according to the above aspect, the first high heat conductive layer may be in contact with the second high heat conductive layer.

[0021] (8) In the light detection element according to the above aspect, the first high heat conductive layer may be made of metal.

[0022] (9) In the light detection element according to the above aspect, the first high thermal conductive layer may include copper, gold, or silver.

[0023] (10) The light detecting element according to the above aspect may further include an insulating layer, wherein the insulating layer covers at least a portion of the side wall of the magnetic element below a lower end of the spacer layer on the second ferromagnetic layer side.

[0024] (11) In the light detecting element according to the above aspect, the first high thermal conductive layer may be an insulator.

[0025] (12) In the light detecting element according to the above aspect, the first high heat conductive layer may have a thermal conductivity greater than 40 W / m·K.

[0026] (13) In the light detection element according to the above aspect, the first high heat conductive layer may include silicon carbide, aluminum nitride, or boron nitride.

[0027] (14) In the light detecting element according to the above aspect, a high resistivity layer may be further provided between the first high heat conductive layer and the second electrode, and the high resistivity layer may have a resistivity higher than that of the first high heat conductive layer.

[0028] (15) In the light detection element according to the above aspect, a low dielectric constant layer may be further provided between the first high thermal conductive layer and the second electrode, wherein the low dielectric constant layer has a lower dielectric constant than the first high thermal conductive layer.

[0029] (16) The light detection element of the second scheme includes: a magnetic element, which includes a first ferromagnetic layer irradiated with light, a second ferromagnetic layer and a spacer layer sandwiched by the first ferromagnetic layer and the second ferromagnetic layer; a first high thermal conductivity layer, which is a non-magnetic metal and is located on the outside of the first ferromagnetic layer.

[0030] (17) In the light detection element according to the above aspect, the first high thermal conductive layer may include copper, gold, or silver.

[0031] (18) A receiving device according to a third aspect includes the light detecting element according to the above aspect.

[0032] (19) A photosensor device according to a fourth aspect includes the photosensor element according to the above aspect.

[0033] Effects of the Invention

[0034] The light detection element, the receiving device, and the light sensor device according to the above-mentioned aspects are excellent in heat dissipation. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a cross-sectional view of the light detection element according to the first embodiment.

[0036] Figure 2 This is a diagram for explaining a first mechanism of a first operation example of the photodetection element according to the first embodiment.

[0037] Figure 3 This is a diagram for explaining the second mechanism of the first operation example of the photodetection element in the first embodiment.

[0038] Figure 4 This is a diagram for explaining a first mechanism of a second operation example of the photodetection element according to the first embodiment.

[0039] Figure 5 This is a diagram for explaining a second mechanism of a second operation example of the photodetection element according to the first embodiment.

[0040] Figure 6 is a cross-sectional view of a light detecting element according to a first modified example.

[0041] Figure 7 is a cross-sectional view of a light detecting element according to a second modification.

[0042] Figure 8 is a cross-sectional view of a light detecting element according to a third modified example.

[0043] Fig. 9 is a cross-sectional view of a light detecting element according to a fourth modified example.

[0044] Fig.10 is a cross-sectional view of a light detecting element according to a fifth modification.

[0045] Fig.11 is a cross-sectional view of a photodetection element according to a sixth modification.

[0046] Fig.12 is a cross-sectional view of a light detecting element according to a seventh modification.

[0047] Fig.13 It is a block diagram of a transceiver according to the first application example.

[0048] Fig.14 This is a conceptual diagram of an example of a communication system.

[0049] Fig.15 This is a conceptual diagram of a cross section of a photosensor device according to a second application example.

[0050] Fig.16 This is a schematic diagram of an example of a terminal device. DETAILED DESCRIPTION

[0051] Hereinafter, the embodiments will be described in detail with reference to the drawings as appropriate. In the drawings used in the following description, in order to make the features easy to understand, the features are sometimes enlarged for convenience, and the size ratios of the components are sometimes different from the actual ones. The materials, sizes, etc. illustrated in the following description are examples, and the present invention is not limited thereto, and can be appropriately changed and implemented within the scope of achieving the effects of the present invention.

[0052] 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 sometimes 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.

[0053] Figure 1It is a cross-sectional view of the light detection element 100 of the first embodiment. The light detection element 100 converts the change in the state of the irradiated light into an electrical signal. The resistance value of the light detection element 100 in the z direction changes according to the state of the irradiated light. The output voltage from the light detection element 100 changes according to the state of the irradiated light. The light in this specification is not limited to visible light, but also includes infrared light with a longer wavelength than visible light or 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 light detection element 100 includes, for example, a magnetic element 10 , a first electrode 11 , a second electrode 12 , a first high thermal conductive layer 20 , an insulating layer 30 , and a substrate 40 .

[0055] The magnetic element 10, for example, has a first ferromagnetic layer 1, a second ferromagnetic layer 2, a spacer layer 3, and a cover layer 4. The spacer layer 3 is located between the first ferromagnetic layer 1 and the second ferromagnetic layer 2. The cover layer 4 covers the upper surface of the magnetic element 10 in the stacking direction. The cover layer 4 is, for example, located on the first ferromagnetic layer 1. In addition to these layers, the magnetic element 10 may also have other layers.

[0056] 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 according to 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.

[0057] 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 including a magnetic body whose magnetization state changes when a predetermined external force is applied. The predetermined external force is, for example, light 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 according to the intensity of the light irradiated to the first ferromagnetic layer 1.

[0058] The first ferromagnetic layer 1 includes a ferromagnetic body. The first ferromagnetic layer 1 includes at least one of the magnetic elements such as Co, Fe or Ni. In addition to the magnetic elements as described above, the first ferromagnetic layer 1 may also include non-magnetic elements such as B, Mg, Hf, Gd, etc. The first ferromagnetic layer 1 may be, for example, an alloy including a magnetic element and a non-magnetic element. The first ferromagnetic layer 1 may be composed of multiple layers. The first ferromagnetic layer 1 may be, for example, a laminated body formed by a CoFeB alloy sandwiched between Fe layers, a laminated body formed by a CoFeB alloy layer sandwiched between CoFe layers, and a laminated body formed by a CoFeB alloy layer sandwiched between CoFe layers.

[0059] 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 direction perpendicular to the film plane (in the z direction).

[0060] 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 that causes 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.

[0061] If the film thickness of the first ferromagnetic layer 1 is reduced, the volume of the ferromagnetic body becomes smaller, and if it is thicker, the volume of the ferromagnetic body becomes larger. The ease with which the magnetization of the first ferromagnetic layer 1 reacts 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 reaction to light, it is preferable to reduce the volume of the first ferromagnetic layer 1 after appropriately designing the magnetic anisotropy of the first ferromagnetic layer 1.

[0062] 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. By utilizing the interface magnetic anisotropy at the interface between the insertion layer and the ferromagnetic layer, the perpendicular magnetic anisotropy of the entire first ferromagnetic layer 1 is improved. The thickness of the insertion layer is, for example, 0.1 nm to 0.6 nm.

[0063] The second ferromagnetic layer 2 is a magnetization fixed layer. The magnetization fixed layer is a layer composed of a magnetic body, and the magnetization state of the magnetic body is not easy to change when a predetermined energy from the outside is applied, compared with the magnetization free layer. For example, the magnetization direction of the magnetization fixed layer is not easy to change when a predetermined energy from the outside is applied, compared with the magnetization free layer. In addition, for example, when a predetermined energy from the outside is applied, the magnetization size of the magnetization fixed layer is not easy to change compared with the magnetization free layer. The coercive force of the second ferromagnetic layer 2 is greater than the coercive force of the first ferromagnetic layer 1, for example. The second ferromagnetic layer 2 has an easy magnetization axis in the same direction as the first ferromagnetic layer 1. The second ferromagnetic layer 2 can be an in-plane magnetization film or a perpendicular magnetization film.

[0064] 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 laminated 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 laminated in this order.

[0065] The magnetization of the second ferromagnetic layer 2 may be fixed by, for example, magnetic coupling with the third ferromagnetic layer using a magnetic coupling layer. In this case, the combination of the second ferromagnetic layer 2, the magnetic coupling layer, and the third ferromagnetic layer may be referred to as a magnetization fixed layer.

[0066] The third ferromagnetic layer is, for example, magnetically coupled to the second ferromagnetic layer 2. The magnetic coupling is, for example, antiferromagnetic coupling and is generated by 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.

[0067] 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 conductive 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.

[0068] 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. Such an element is called an MTJ element. In this case, the magnetic element 10 can exhibit a tunnel magnetoresistance (TMR: Tunnel Magnetoresistance) effect. For example, when the spacer layer 3 is composed of a metal, the magnetic element 10 can exhibit a giant magnetoresistance (GMR: Giant Magnetoresistance) effect. Such an element is called a GMR element. The magnetic element 30 is sometimes called an MTJ element, a GMR element, etc., depending on the constituent material of the spacer layer 3, and is also generally referred to as a magnetoresistance effect element.

[0069] 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, elements such as Al, B, Si, Mg or magnetic elements such as Co, Fe, Ni can also be contained in these insulating materials. The film thickness of the spacer layer 3 is adjusted so that a high TMR effect is exhibited between the first ferromagnetic layer 1 and the second ferromagnetic layer 2, thereby obtaining a high magnetoresistance change rate. In order to efficiently utilize the TMR effect, the film thickness of the spacer layer 3 can be set to about 0.5 to 5.0 nm, or it can be set to about 1.0 to 2.5 nm.

[0070] When the spacer layer 3 is made of a non-magnetic conductive material, conductive materials such as Cu, Ag, Au or Ru can be used. In order to efficiently utilize the GMR effect, the film thickness of the spacer layer 3 can be set to about 0.5 to 5.0 nm, or about 2.0 to 3.0 nm.

[0071] 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 also be set to about 1.0 to 4.0 nm.

[0072] When the spacer layer 3 is used, i.e., a layer including a energization point composed of a conductor in a non-magnetic insulator, a structure in which a energization 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 also be set to about 1.0 to 2.5 nm. The energization point is, for example, a columnar body with a diameter of 1 nm or more and 5 nm or less when observed from a direction perpendicular to the film surface.

[0073] The capping layer 4 is located between the first ferromagnetic layer 1 and the first electrode 11. The capping layer 4 prevents damage to the lower layer during the process and improves the crystallinity of the lower layer during annealing. The film thickness of the capping layer 4 is, for example, 3 nm or less so that sufficient light can be irradiated to the first ferromagnetic layer 1. The capping layer 4 is, for example, MgO, W, Mo, Ru, Ta, Cu, Cr, or a laminated film thereof.

[0074] In addition to these layers, the magnetic element 10 may also have a base layer, a perpendicular magnetization induction layer, etc. The base layer is located between the second ferromagnetic layer 2 and the second electrode 12. 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.

[0075] The perpendicular magnetization induction layer is formed when the first ferromagnetic layer 1 is a perpendicular magnetization film. The perpendicular magnetization induction layer is stacked on the first ferromagnetic layer 1. The perpendicular magnetization induction layer senses the perpendicular magnetic anisotropy of the first ferromagnetic layer 1. The perpendicular magnetization induction layer is, for example, magnesium oxide, W, Ta, Mo, etc. When the perpendicular magnetization induction layer is magnesium oxide, magnesium oxide is preferably oxygen-deficient in order to improve conductivity. The film thickness of the perpendicular magnetization induction layer is, for example, not less than 0.5 nm and not more than 2.0 nm.

[0076] The first electrode 11 is in contact with a first surface of the magnetic element 10. The first surface is a surface on the first ferromagnetic layer side of the magnetic element 10 in the z direction. The first electrode 11 has a transmittance to the wavelength band of light irradiated to the magnetic element 10, for example.

[0077] The first electrode 11 includes, for example, an oxide that is transmissive to the wavelength band of light irradiated to the magnetic element 10. The first electrode 11 is a transparent electrode made of a transparent electrode material including oxides such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), and indium gallium zinc oxide (IGZO). The first electrode 11 may have a structure having a plurality of columnar metals in these transparent electrode materials. In this case, the film thickness of the first electrode 11 is, for example, 10 nm to 300 nm. As the first electrode 11, it is not necessary to use the transparent electrode material described above, but a metal material such as Au, Cu, or Al is used in a thin film thickness so that light from the outside reaches the first ferromagnetic layer 1. When a metal is used as the material of the first electrode 11, the film thickness of the first electrode 11 is, for example, 3 to 10 nm. In particular, Au has a higher transmittance of light with a wavelength close to blue than other metal materials. In addition, the first electrode 11 may also have an anti-reflection film on the irradiated surface of the irradiated light.

[0078] The second electrode 12 is made of a conductive material. The second electrode 12 is made of a metal such as Cu, Al, or Au. Ta or Ti may be stacked on top and bottom of these metals. In addition, 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, TiN or TaN may be used as the second electrode 12. The film thickness of the second electrode 12 is, for example, 200 nm to 800 nm.

[0079] The second electrode 12 may also be transparent to the light irradiated to the magnetic element 10. As the material of the second electrode 12, a transparent electrode material of an oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium gallium zinc oxide (IGZO) or the like may be used, as in the case of the first electrode 11. Even when light is irradiated from the first electrode 11 side, light may sometimes reach the second electrode 12 depending on the intensity of the light. However, in this case, the second electrode 12 is configured in a manner including a transparent electrode material of an oxide, thereby suppressing the reflection of light at the interface between the second electrode 12 and the layer in contact therewith, as compared with the case where the second electrode 12 is configured of a metal.

[0080] When viewed from the z direction, the first high thermal conductive layer 20 is located outside the first ferromagnetic layer 1. The first high thermal conductive layer 20 is, for example, located outside the in-plane direction of the magnetic element 10, and covers at least a portion of the side wall of the magnetic element 10. The first high thermal conductive layer 20 is, for example, connected to the magnetic element 10 via the insulating layer 30. The first high thermal conductive layer 20, for example, surrounds at least a portion of the magnetic element 10. For example, the first high thermal conductive layer 20 surrounds the first ferromagnetic layer 1 of the magnetic element 10. The first high thermal conductive layer 20, for example, contacts the first electrode 11. When the first high thermal conductive layer 20 contacts the first electrode 11, a heat path is formed from the first high thermal conductive layer 20 to the wiring via the first electrode 11, and heat can be efficiently dissipated from the magnetic element 10.

[0081] The first high thermal conductive layer 20 has a higher thermal conductivity than the first electrode 11. The first high thermal conductive layer 20 has a higher thermal conductivity than, for example, the insulating layer 30. The thermal conductivity of the first high thermal conductive layer 20 is, for example, greater than 40 W / m·K. Part of the heat generated by the magnetic element 10 is dissipated through the first high thermal conductive layer 20.

[0082] The first high thermal conductive layer 20 is, for example, a metal. The first high thermal conductive layer 20 is, for example, a non-magnetic body. When the first high thermal conductive layer 20 is a non-magnetic body, no leakage magnetic field is generated from the first high thermal conductive layer 20, and the magnetic characteristics of the magnetic element 10 can be suppressed from being reduced. When the first high thermal conductive layer 20 is a non-magnetic metal, for example, even if the first electrode 11 is a metal, the first electrode 11 has a higher thermal conductivity than the first high thermal conductive layer 20, and the thermal conductivity of the first high thermal conductive layer 20 is also high. Therefore, even if the first electrode 11 has a higher thermal conductivity than the first high thermal conductive layer 20, heat can be efficiently dissipated from the magnetic element 10. The first high thermal conductive layer 20 contains, for example, copper, gold, or silver.

[0083] The first high thermal conductive layer 20 may be an insulator. When the first high thermal conductive layer 20 is composed of an insulator, the first high thermal conductive layer 20 includes, for example, silicon carbide, aluminum nitride, or boron nitride.

[0084] The insulating layer 30 is located between the magnetic element 10 and the first high thermal conductive layer 20. The insulating layer 30 covers the periphery of the magnetic element 10. The insulating layer 30 is, for example, an oxide, nitride, or oxynitride of Si, Al, or Mg. The insulating layer 30 is, for example, silicon oxide (SiO x ), Silicon Nitride (SiN x ), silicon carbide (SiC), chromium nitride, silicon carbide nitride (SiCN), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), zirconium oxide (ZrO x )wait.

[0085] 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 12, the second ferromagnetic layer 2, the spacer layer 3, the first ferromagnetic layer 1, and the cover layer 4 are sequentially laminated on a substrate. Each layer is formed by sputtering, for example.

[0086] Next, the laminated film is annealed. The annealing temperature is, for example, 250°C to 450°C. When the substrate is a circuit substrate, it is preferably annealed at 400°C or above. Thereafter, the laminated film is processed into a predetermined columnar body by photolithography and etching. The columnar body can be a cylinder or a prism. For example, the shortest width of the columnar body when observed from the z direction can be greater than 10 nm and less than 2000 nm, or can be greater than 30 nm and less than 500 nm.

[0087] Next, the insulating layer 30 is formed so as to cover the side surfaces of the columnar body. The insulating layer 30 may be stacked multiple times. Next, the first high thermal conductive layer 20 is formed on the insulating layer 30. Next, the upper surface of the cover layer 4 is exposed from the insulating layer 30 and the first high thermal conductive layer 20 by chemical mechanical polishing (CMP), and the first electrode 11 is formed on the cover layer 4. Through the above steps, the light detection element 100 is obtained.

[0088] Next, some 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 light being irradiated 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 two levels of a first intensity and a second intensity is described as an example. The intensity of the light of the second intensity is made 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.

[0089] Figure 2 and Figure 3 It is a diagram for explaining a first operation example of the light detection element 100 according to the first embodiment. Figure 2 is a diagram for explaining the first mechanism of the first operation example, Figure 3 This is a diagram for explaining the second mechanism of the first operation example. Figure 2 and Figure 3 In the upper graph of , the vertical axis represents the intensity of light irradiated to the first ferromagnetic layer 1 , and the horizontal axis represents time. Figure 2 and Figure 3 In the graph below, the vertical axis is the resistance value of the magnetic element 10 in the z direction, and the horizontal axis is time.

[0090] First, when the first ferromagnetic layer 1 is irradiated with light of a first intensity (hereinafter referred to as an initial state), the magnetization M1 of the first ferromagnetic layer 1 and the magnetization M2 of the second ferromagnetic layer 2 are in parallel, and the resistance value in the z direction of the magnetic element 10 represents a first resistance value R 1 , the magnitude of the output voltage from the magnetic element 10 represents the first value. By making the induced current Is flow in the z direction of the magnetic element 10, a voltage is generated at both ends of the z direction of the magnetic element 10, and the resistance value of the z direction of the magnetic element 10 is calculated using Ohm's law based on the voltage value. The output voltage from the magnetic element 10 is generated between the first electrode 11 and the second electrode 12. Figure 2In the example shown, the induced current Is is caused to flow from the first ferromagnetic layer 1 to the second ferromagnetic layer 2. By causing the induced 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 in the initial state, the magnetization M1 is parallel to the magnetization M2. In addition, by causing the induced 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.

[0091] 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 light is not irradiated to the first ferromagnetic layer 1 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 refers to, for example, the tilt angle relative to the z direction, the size, etc.

[0092] For example, Figure 2 As shown in FIG. 1 , when the intensity of light irradiated to the first ferromagnetic layer 1 changes from the first intensity to the second intensity, the magnetization M1 is inclined relative to the z direction. Figure 3 As shown, when the intensity of light irradiated to 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 according to the intensity of light irradiation, the tilt angle is greater than 0° and less than 90°.

[0093] 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 represents the second resistance value R 2 , the magnitude of the output voltage from the magnetic element 10 represents the second value. The second resistance value R 2 Greater than the first resistance value R 1 , the second value of the output voltage is greater than the first value. The second resistance value R 2 The resistance value when the magnetization M1 and the magnetization M2 are parallel (the first resistance value R 1 ) and the resistance value when magnetization M1 and magnetization M2 are antiparallel.

[0094] exist Figure 2 In the case shown, the 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. Therefore, the magnetization M1 is returned to a state parallel to the magnetization M2, and when the intensity of the light irradiated to the first ferromagnetic layer 1 changes from the second intensity to the first intensity, the magnetic element 10 returns to the initial state. Figure 3In the case shown, when 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 any case, the resistance value of the magnetic element 10 in the z direction returns to the first resistance value R 1 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 R 2 Change to the first resistance value R 1 .

[0095] The output voltage from the light detection element 100 can change 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 is converted into a change in the output voltage from the light detection element 100. That is, the light detection element 100 can convert light into an electrical signal. For example, when the output voltage from the light detection element 100 is above a threshold value, it is processed as a first signal (for example, "1"), and when it is below the threshold value, it is processed as a second signal (for example, "0").

[0096] Here, in the initial state, the case where the magnetization M1 is parallel to the magnetization M2 is used as an example for explanation, but in the initial state, the magnetization M1 and the magnetization M2 may be antiparallel. In this case, the greater the change in the state of the magnetization M1 (for example, the greater the angle change from the initial state of the magnetization M1), the smaller the resistance value in the z direction of the magnetic element 10. In the case where the magnetization M1 and the magnetization M2 are antiparallel as the initial state, the induced current preferably flows from the second ferromagnetic layer 2 to the first ferromagnetic layer 1. By making the induced current flow in this direction, the 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 in the initial state, the magnetization M1 and the magnetization M2 are antiparallel.

[0097] In the first operation example, the case where the light irradiating the first ferromagnetic layer 1 has two levels of first intensity and second intensity is described as an example, while 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 an analog manner is described.

[0098] Figure 4 and Figure 5 It is a diagram for explaining a second 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 upper graph of , the vertical axis represents the intensity of light irradiated to the first ferromagnetic layer 1 , and the horizontal axis represents time. Figure 4and Figure 5 In the graph below, the vertical axis is the resistance value of the magnetic element 10 in the z direction, and the horizontal axis is time.

[0099] exist Figure 4 In the case where the intensity of light irradiated to the first ferromagnetic layer 1 changes, the magnetization M1 of the first ferromagnetic layer 1 tilts from the initial state due to the energy from the outside based on the irradiation of light. The angle between the direction of the magnetization M1 of the first ferromagnetic layer 1 in the state where the first ferromagnetic layer 1 is not irradiated with light and the direction of the magnetization M1 in the state where the light is irradiated is greater than 0° and less than 90°.

[0100] When the magnetization M1 of the first ferromagnetic layer 1 tilts from the initial state, the resistance value in the z direction of the magnetoresistive element 10 changes. As a result, the output voltage from the magnetic element 10 changes. For example, according to the tilt 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 R 2 , the third resistance value R 3 , the fourth resistance value R 4 The output voltage from the magnetic element 30 changes to a second value, a third value, and a fourth value. The resistance value is the first resistance value R 1 , the second resistance value R 2 , the third resistance value R 3 , the fourth resistance value R 4 The output voltage from the magnetic element 30 increases in the order of the first value, the second value, the third value, and the fourth value.

[0101] In the case of the magnetic element 10, when the intensity of light irradiated to the first ferromagnetic layer 1 changes, the output voltage from the magnetic element 10 (the resistance value in the z direction of the magnetic element 10) changes. 1 ) is set to "0", and the second value (the second resistance value R 2 ) is set to "1", and the third value (the third resistance value R 3 ) is set to "2", and the fourth value (the fourth resistance value R 4 ) is set to "3", the light detection element 100 can output information of four values. Here, as an example, a case of reading four values ​​is given, but the number of read values ​​can be freely designed according to the setting of the threshold value of the output voltage (resistance value of the magnetic element 10) from the magnetic element 10. In addition, the light detection element 100 can also directly output analog values.

[0102] in addition, Figure 5Similarly, when the intensity of the light irradiated to the first ferromagnetic layer 1 changes, the magnitude of the magnetization M1 of the first ferromagnetic layer 1 decreases from the initial state due to the energy from the outside based on the irradiation of the light. When the magnetization M1 of the first ferromagnetic layer 1 decreases from the initial state, the resistance value in the z direction of the magnetoresistive element 10 changes. As a result, the output voltage from the magnetic element 10 changes. For example, according to the magnitude 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 R 2 , the third resistance value R 3 , the fourth resistance value R 4 , the output voltage from the magnetic element 10 changes to the second value, the third value, and the fourth value. Figure 4 Similarly to the case of , the light detection element 100 can output the differences in these output voltages (resistance values) as multi-valued or analog data.

[0103] 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.

[0104] 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, the magnetization M1 and the magnetization M2 may be antiparallel in the initial state.

[0105] As described above, the light detecting element 100 of the first embodiment can convert light irradiated to the magnetic element 10 into an output voltage from the magnetic element 10, thereby converting light into an electrical signal. In addition, since the first high thermal conductivity layer 20 having a high thermal conductivity exists on the outside of the magnetic element 10 that generates heat when irradiated with light, heat dissipation from the magnetic element 10 can be promoted. That is, when the irradiation of light to the first ferromagnetic layer 1 is stopped, the magnetic element 10 is cooled quickly, and the recovery of the magnetization M1 to the initial state becomes faster. When the recovery of the magnetization M1 of the first ferromagnetic layer 1 to the initial state is fast, the response characteristics of the light detecting element 100 to light are improved. In other words, the response characteristics of the light detecting element 100 to light become high speed.

[0106] As mentioned above, although the 1st embodiment was demonstrated in detail with reference to drawings, the 1st embodiment is not limited to this example.

[0107] (First Modification)

[0108] Figure 61 is a cross-sectional view of a light detecting element 101 of a first variant. The light detecting element 101 includes, for example, a magnetic element 10, a first electrode 11, a second electrode 12, a first high thermal conductive layer 21, insulating layers 30, 31, and a substrate 40. In the first variant, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

[0109] When viewed from the z direction, the first high thermal conductive layer 21 is located outside the first ferromagnetic layer 1. The first high thermal conductive layer 21 is connected to the magnetic element 10, for example, via the insulating layer 30. The first high thermal conductive layer 21, for example, surrounds at least a portion of the magnetic element 10. For example, the first high thermal conductive layer 21 surrounds the first ferromagnetic layer 1 of the magnetic element 10. The first high thermal conductive layer 21 is in contact with the first electrode 11, for example. The first high thermal conductive layer 21 is sandwiched between the insulating layer 30 and the insulating layer 31.

[0110] The first high thermal conductive layer 21 has a higher thermal conductivity than the first electrode 11. The first high thermal conductive layer 21 is made of the same material as the first high thermal conductive layer 20.

[0111] The insulating layer 31 covers the upper surface of the first high thermal conductive layer 21. The insulating layer 31 and the insulating layer 30 sandwich the first high thermal conductive layer 21. The insulating layer 31 is made of the same material as the insulating layer 30.

[0112] Since the light detection element 101 according to the first modification example includes the first high thermal conductive layer 21 , the same effects as those of the light detection element 100 are achieved.

[0113] (Second Modification)

[0114] Figure 7 1 is a cross-sectional view of a light detecting element 102 of a second modified example. The light detecting element 102 includes, for example, a magnetic element 10, a first electrode 11, a second electrode 12, a first high thermal conductive layer 22, insulating layers 30 and 31, and a substrate 40. In the second modified example, the same components as those of the first modified example are denoted by the same reference numerals, and description thereof is omitted.

[0115] When viewed in the z direction, the first high thermal conductive layer 22 is located outside the first ferromagnetic layer 1. The first high thermal conductive layer 22 is different from the first high thermal conductive layer 21 of the first modification in that it is not in contact with the first electrode 11.

[0116] The light detection element 102 according to the second modification example has the first high thermal conductive layer 22 , and thus has the same effects as those of the light detection element 100 .

[0117] (Third Modification)

[0118] Figure 81 is a cross-sectional view of a light detecting element 103 of a third modified example. The light detecting element 103 includes, for example, a magnetic element 10, a first electrode 11, a second electrode 12, a first high thermal conductive layer 20, an insulating layer 30, a substrate 40, and a second high thermal conductive layer 50. In the third modified example, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

[0119] The second high thermal conductive layer 50 is in contact with the side wall of the first electrode 11. The second high thermal conductive layer 50 surrounds the periphery of the first electrode 11, for example. The second high thermal conductive layer 50 has a higher thermal conductivity than the first electrode 11. The second high thermal conductive layer 50 is in contact with the first high thermal conductive layer 20, for example. When the second high thermal conductive layer 50 is in contact with the first high thermal conductive layer 20, heat is discharged from the first high thermal conductive layer 20 to the second high thermal conductive layer 50, and heat can be efficiently dissipated from the magnetic element 10. The same material as the first high thermal conductive layer 20 can be used for the second high thermal conductive layer 50. The first high thermal conductive layer 20 and the second high thermal conductive layer 50 may be the same material or different materials.

[0120] The light detection element 103 of the third modification example has the first high heat conductive layer 20, and thus has the same effect as the light detection element 100. In addition, the light detection element 103 has the second high heat conductive layer 50, and thus has a more excellent heat dissipation property.

[0121] (Fourth Modification)

[0122] Fig. 9 1 is a cross-sectional view of a light detecting element 104 of a fourth modification. The light detecting element 104 includes, for example, a magnetic element 10, a first electrode 11, a second electrode 12, a first high thermal conductive layer 23, an insulating layer 32, and a substrate 40. In the fourth modification, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

[0123] When viewed from the z direction, the first high thermal conductive layer 23 is located outside the first ferromagnetic layer 1. The first high thermal conductive layer 23 is in direct contact with the magnetic element 10. The first high thermal conductive layer 23 is, for example, in direct contact with at least a portion of the side surface of the first ferromagnetic layer 1. The first high thermal conductive layer 23 surrounds at least a portion of the magnetic element 10. For example, the first high thermal conductive layer 23 surrounds the first ferromagnetic layer 1 of the magnetic element 10.

[0124] The first high thermal conductive layer 23 has a higher thermal conductivity than the first electrode 11. The first high thermal conductive layer 23 is made of the same material as the first high thermal conductive layer 20.

[0125] A portion of the insulating layer 32 is located between the magnetic element 10 and the first high thermal conductive layer 23. The insulating layer 32 is made of the same material as the insulating layer 30. The insulating layer 32 covers at least a portion of the side wall of the magnetic element 10 below the lower end 3U of the spacer layer 3. Since the insulating layer 32 covers the portion below the lower end 3U of the spacer layer 3, even when the first high thermal conductive layer 23 is a conductor, a short circuit between the first high thermal conductive layer 23 and the second ferromagnetic layer 2 can be prevented.

[0126] The light detecting element 104 of the fourth modification has the first high thermal conductive layer 23, and thus has the same effect as the light detecting element 100. In addition, the first high thermal conductive layer 23 is in direct contact with the first ferromagnetic layer 1, thereby being able to more efficiently dissipate the heat generated by the first ferromagnetic layer 1. In addition, when the first high thermal conductive layer 23 is a conductor, the insulating layer 32 prevents the first high thermal conductive layer 23 and the second ferromagnetic layer 2 from short-circuiting, thereby being able to suppress the reduction of the magnetic characteristics of the magnetic element 10.

[0127] (Fifth Modification)

[0128] Fig.10 1 is a cross-sectional view of a light detecting element 105 of a fifth modification. The light detecting element 105 includes, for example, a magnetic element 10, a first electrode 11, a second electrode 12, a first high thermal conductive layer 25, and a substrate 40. In the fifth modification, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

[0129] The first high thermal conductive layer 25 is located outside the first ferromagnetic layer 1 when viewed from the z direction.

[0130] The first high thermal conductive layer 25 is in direct contact with the magnetic element 10 . The first high thermal conductive layer 25 surrounds the magnetic element 10 .

[0131] The first high thermal conductive layer 25 has a higher thermal conductivity than the first electrode 11. The first high thermal conductive layer 25 is an insulator. The thermal conductivity of the first high thermal conductive layer 25 is, for example, greater than 40 W / m·K. The first high thermal conductive layer 25 includes, for example, silicon carbide, aluminum nitride, or boron nitride.

[0132] The light detecting element 105 of the fifth modification has the first high thermal conductive layer 25, and thus has the same effect as the light detecting element 100. In addition, since the first high thermal conductive layer 25 has insulating properties, it can be in direct contact with the entire side surface of the magnetic element 10. As a result, the light detecting element 105 can efficiently dissipate heat from the magnetic element 10.

[0133] (Sixth Modification)

[0134] Fig.111 is a cross-sectional view of a light detecting element 106 according to a sixth modification. The light detecting element 106 includes, for example, a magnetic element 10, a first electrode 11, a second electrode 12, a first high thermal conductive layer 26, a substrate 40, and a high resistivity layer 60. In the sixth modification, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

[0135] When viewed from the z direction, the first high thermal conductive layer 26 is located outside the first ferromagnetic layer 1. The first high thermal conductive layer 26 is, for example, in direct contact with the first ferromagnetic layer 1. The high resistivity layer 60 may also be located between the first high thermal conductive layer 26 and the first ferromagnetic layer 1. The first high thermal conductive layer 26 surrounds the first ferromagnetic layer 1, for example.

[0136] The first high thermal conductive layer 26 has a higher thermal conductivity than the first electrode 11. The first high thermal conductive layer 26 is an insulator. The thermal conductivity of the first high thermal conductive layer 26 is, for example, greater than 40 W / m·K. The first high thermal conductive layer 26 includes, for example, silicon carbide, aluminum nitride, or boron nitride.

[0137] The high resistivity layer 60 is located between the first high thermal conductive layer 26 and the second electrode 12. A portion of the high resistivity layer 60 may be located between the magnetic element 10 and the first high thermal conductive layer 26. The high resistivity layer 60 has a greater resistivity than the first high thermal conductive layer 26.

[0138] The high resistivity layer 60 is, for example, an insulator. The high resistivity layer 60 also depends on the material constituting the first high thermal conductivity layer 26, for example, aluminum oxide (Al 2 O 3 ), zirconium oxide (ZrO 2 ), silicon oxide (SiO 2 ), silicon nitride (Si 3 N 4 ), forsterite (2MgO·SiO 2 ), yttrium oxide (Y 2 O 3 ), aluminum nitride (AlN), and boron nitride (BN).

[0139] For example, when the first high thermal conductive layer 26 is made of silicon carbide (SiC), the high resistivity layer 60 is preferably made of aluminum oxide (Al 2 O 3 ), zirconium oxide (ZrO 2 ), silicon oxide (SiO 2 ), silicon nitride (Si 3 N 4 ), forsterite (2MgO·SiO 2 ), yttrium oxide (Y 2 O 3For example, when the first high thermal conductivity layer 26 is aluminum nitride (AlN) or boron nitride (BN), the high resistivity layer 60 is preferably silicon oxide (SiO 2 ).

[0140] The light detecting element 106 of the sixth modification has the first high heat conductive layer 26 and thus has the same effect as the light detecting element 100. In addition, the high resistivity layer 60 is provided between the first electrode 11 and the second electrode 12, thereby improving the insulation between the first electrode 11 and the second electrode 12.

[0141] (Seventh Modification)

[0142] Fig.12 1 is a cross-sectional view of a light detecting element 107 according to a seventh modification. The light detecting element 107 includes, for example, a magnetic element 10, a first electrode 11, a second electrode 12, a first high thermal conductive layer 26, a substrate 40, and a low dielectric constant layer 70. In the seventh modification, the same components as those in the sixth modification are denoted by the same reference numerals, and description thereof is omitted.

[0143] The low dielectric constant layer 70 is located between the first high thermal conductive layer 26 and the second electrode 12. A portion of the low dielectric constant layer 70 may be located between the magnetic element 10 and the first high thermal conductive layer 26. The low dielectric constant layer 70 has a lower dielectric constant than the first high thermal conductive layer 26.

[0144] The low dielectric constant layer 70 is, for example, an insulator. The low dielectric constant layer 70 depends on the material constituting the first high thermal conductive layer 26, for example, silicon oxide (SiO 2 ), silicon nitride (Si 3 N 4 ), forsterite (2MgO·SiO 2 ), aluminum nitride (AlN), and boron nitride (BN).

[0145] For example, when the first high thermal conductive layer 26 is made of silicon carbide (SiC), the low dielectric constant layer 70 is preferably made of silicon oxide (SiO 2 ), silicon nitride (Si 3 N 4 ), forsterite (2MgO·SiO 2 ), aluminum nitride (AlN), boron nitride (BN). For example, when the first high thermal conductive layer 26 is aluminum nitride (AlN), the low dielectric constant layer 70 is preferably silicon oxide (SiO 2 ), forsterite (2MgO·SiO 2 For example, when the first high thermal conductive layer 26 is made of boron nitride (BN), the low dielectric constant layer 70 is preferably made of silicon oxide (SiO 2).

[0146] The light detecting element 107 of the seventh modification has the first high heat conductive layer 26 and thus has the same effect as the light detecting element 100. In addition, the low dielectric constant layer 70 is provided between the first electrode 11 and the second electrode 12, thereby reducing the capacitance between the first electrode 11 and the second electrode 12.

[0147] In summary, the present invention is not limited to the above-mentioned embodiments and modifications, 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 modifications can be combined respectively.

[0148] The light detection element of the above-described embodiment and modified example can be applied to a light sensor device such as an image sensor, a transceiver of a communication system, and the like.

[0149] Fig.13 1 is a block diagram of a transceiver 1000 according to a first application example. The transceiver 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.

[0150] 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. The light detecting element 301 converts the optical 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. Light is irradiated to the first ferromagnetic layer 1 of the light detecting element 301, and the light includes the optical signal L1 with light intensity variation. Alternatively, a lens may be arranged on the first ferromagnetic layer 1 side in the stacking direction of the light detecting element 301, and the light focused by the lens is irradiated to the first ferromagnetic layer 1. The lens may also be formed in the wafer process of forming the light detecting element 301. In addition, light passing through a waveguide may be irradiated to the first ferromagnetic layer 1 of the light detecting element 301. The light irradiated to the first ferromagnetic layer 1 of the light detecting element 301 is, for example, laser light. The signal processing unit 302 processes the electrical signal converted by the light detecting element 301. The signal processing unit 302 receives a signal included in the optical signal L1 by processing the electric signal generated from the light detection element 301 .

[0151] The transmitting device 400 includes, for example, a light source 401, an electric signal generating element 402, and an optical modulation element 403. The light source 401 is, for example, a laser element. The light source 401 may 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 be integrated with the signal conversion element of the signal processing unit 302. The optical modulation element 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.

[0152] Fig.14 This is a conceptual diagram of an example of a communication system. Fig.14 The communication system shown has two terminal devices 500. The terminal devices 500 are, for example, smartphones, tablet computers, personal computers, and the like.

[0153] Each terminal device 500 includes a receiving device 300 and a transmitting device 400. An optical signal transmitted from the transmitting device 400 of one terminal device 500 is received by the receiving device 300 of another terminal device 500. 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 the light detection element 301. Since the above-mentioned light detection elements 100 to 107 have excellent heat dissipation properties, Fig.14 The communication system shown is capable of high-speed communication.

[0154] Fig.15 2 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 .

[0155] Each of the plurality of light sensors S includes, for example, a light detection element 100, a filter F, and a lens R. Fig.15 , an example using the light detection element 100 is shown, but the light detection elements 101 to 106 may be used instead of the light detection element 100. The light that has passed through the filter F is irradiated to the light detection element 100. As described above, the light detection element 100 converts the light irradiated to the magnetic element 10 into an electrical signal. The light detection element 100 preferably operates in the manner of the second operation example.

[0156] The filter F selects light of a specific wavelength and transmits light of a specific wavelength band. The wavelength bands of light that can be transmitted by each filter F can be the same or different. For example, the optical sensor device 2000 can also include: an optical sensor S (hereinafter referred to as a blue sensor) having a filter F that can transmit blue (a wavelength band above 380nm and below 490nm); an optical sensor S (hereinafter referred to as a green sensor) having a filter F that can transmit green (a wavelength band above 490nm and below 590nm); and an optical sensor S (hereinafter referred to as a red sensor) having a filter F that can transmit red (a wavelength band above 590nm and below 800nm). By making the blue sensor, the green sensor, and the red sensor into one pixel and arranging the pixels, the optical sensor device 2000 can be used as an image sensor.

[0157] The lens R focuses the light toward the magnetic element 10 . Fig.15 The optical sensor S shown has one light detection element 100 disposed below one filter F. However, a plurality of light detection elements 100 may be disposed below one filter F.

[0158] 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 output from the output terminal 112 .

[0159] The wiring layer 120 has a plurality of wirings 121. An interlayer insulating film 122 is present between the plurality of wirings 121. The wirings 121 electrically connect each of the optical sensors S to the circuit substrate 110 and between the respective operation circuits formed on the circuit substrate 110. Each of the optical sensors S is connected to the circuit substrate 110 via, for example, a through wiring that penetrates the interlayer insulating film 122 in the z direction. By shortening the distance between the wirings between each of the optical sensors S and the circuit substrate 110, noise can be reduced.

[0160] 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 or 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 carbide nitride (SiCN), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), zirconium oxide (ZrO x )wait.

[0161] The above-described optical sensor device 2000 can be used in, for example, a terminal device. Fig.16It is a schematic diagram of an example of the terminal device 600. Fig.16 The left part is the front side of the terminal device 600. Fig.16 The right part 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.16 In the embodiment, a smartphone is shown as an example of the terminal device 600, but the present invention is not limited to this case. In addition to the smartphone, the terminal device 600 is, for example, a tablet computer, a personal computer, a digital camera, etc.

[0162] Description of Reference Numerals

[0163] 1...first ferromagnetic layer, 2...second ferromagnetic layer, 3...spacer layer, 3U...lower end, 4...covering layer, 10...magnetic element, 11...first electrode, 12...second electrode, 20, 21, 22, 23, 25, 26...first high thermal conductivity layer, 30, 31, 32...insulating layer, 40...substrate, 50...second high thermal conductivity layer, 60...high resistivity layer, 70...low dielectric constant layer, 100, 101, 102, 103, 104, 105, 106, 107...light detection element, 110...electric Circuit board, 111...analog-to-digital converter, 112...output terminal, 120...wiring layer, 121...wiring, 122...interlayer insulating layer, 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...filter, R...lens, S...optical sensor.

Claims

1. A light detection element, comprising: A magnetic element having a first ferromagnetic layer to which light is irradiated, a second ferromagnetic layer, and a spacer layer sandwiched by the first ferromagnetic layer and the second ferromagnetic layer; a first electrode and a second electrode, the first electrode being in contact with a first surface of the magnetic element on the first ferromagnetic layer side in a stacking direction, and the second electrode being in contact with a second surface on the opposite side of the first surface; as well as a first high thermal conductivity layer located outside the first ferromagnetic layer in the in-plane direction and having a higher thermal conductivity than the first electrode; The first electrode includes an oxide having transmissive properties with respect to the light.

2. The light detecting element according to claim 1, wherein The first high thermal conductive layer is a non-magnetic material.

3. The light detecting element according to claim 1, wherein The first high thermal conductive layer is in contact with the first ferromagnetic layer.

4. The light detecting element according to claim 1, wherein The first high thermal conductive layer contacts the first electrode.

5. The light detecting element according to claim 1, wherein Also includes a second high heat conduction layer, The second high thermal conductive layer contacts the side wall of the first electrode, The second high thermal conductive layer has higher thermal conductivity than the first electrode.

6. The light detecting element according to claim 5, wherein The first high heat conductive layer is in contact with the second high heat conductive layer.

7. The light detecting element according to claim 1, wherein The first high heat conductive layer is metal.

8. The light detecting element according to claim 7, wherein The first high thermal conductivity layer includes copper, gold or silver.

9. The light detecting element according to claim 1, wherein Also includes an insulating layer, The insulating layer covers at least a portion of the side wall of the magnetic element that is below a lower end of the spacer layer on the second ferromagnetic layer side.

10. The light detecting element according to claim 1, wherein The first high thermal conductivity layer is an insulator.

11. The light detecting element according to claim 10, wherein The thermal conductivity of the first high thermal conductivity layer is greater than 40 W / m·K.

12. The light detecting element according to claim 10 or 11, wherein: The first high thermal conductivity layer includes silicon carbide, aluminum nitride or boron nitride.

13. The light detecting element according to claim 10 or 11, wherein: A high resistivity layer is further provided between the first high thermal conductivity layer and the second electrode, The high resistivity layer has a higher resistivity than the first high heat conductive layer.

14. The light detecting element according to claim 12, wherein A high resistivity layer is further provided between the first high thermal conductivity layer and the second electrode, The high resistivity layer has a higher resistivity than the first high heat conductive layer.

15. The light detecting element according to claim 10 or 11, wherein: A low dielectric constant layer is further provided between the first high thermal conductivity layer and the second electrode. The low dielectric constant layer has a lower dielectric constant than the first high thermal conductive layer.

16. The light detecting element according to claim 12, wherein A low dielectric constant layer is further provided between the first high thermal conductivity layer and the second electrode. The low dielectric constant layer has a lower dielectric constant than the first high thermal conductive layer.

17. The light detecting element according to claim 14, wherein A low dielectric constant layer is further provided between the first high thermal conductivity layer and the second electrode. The low dielectric constant layer has a lower dielectric constant than the first high thermal conductive layer.

18. A light detection element, comprising: A magnetic element having a first ferromagnetic layer to which light is irradiated, a second ferromagnetic layer, and a spacer layer sandwiched by the first ferromagnetic layer and the second ferromagnetic layer; a first electrode and a second electrode, the first electrode being in contact with a first surface of the magnetic element on the first ferromagnetic layer side in a stacking direction, and the second electrode being in contact with a second surface on the opposite side of the first surface; as well as The first high thermal conductivity layer is a non-magnetic metal and is located outside the first ferromagnetic layer in the in-plane direction. The first electrode includes an oxide having transmissive properties with respect to the light.

19. The light detecting element according to claim 18, wherein The first high thermal conductivity layer includes copper, gold or silver. 20 . A receiving device comprising the light detecting element according to claim 1 . 21 . A photosensor device comprising the photodetection element according to claim 1 .

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