JP7708607B2 - Transmitting and receiving equipment - Google Patents

Description

The present invention relates to a transmitting/receiving device.

Photoelectric conversion elements are used for a variety of purposes.

As the Internet becomes more widespread, communication volume has increased dramatically, and the importance of optical communication is growing. Optical communication is a means of communication in which electrical signals are converted into optical signals and used to send and receive data.

For example, Patent Document 1 describes a receiving device that receives an optical signal using a photodiode. The photodiode is, for example, a pn junction diode that uses a semiconductor pn junction.

JP 2001-292107 A

As information and communication technology advances, there is a demand for ever faster communication speeds. In optical communications, there is a demand for higher signal modulation frequencies. Photodetectors using semiconductor pn junctions are widely used as photoelectric conversion elements, but new breakthroughs are needed for further development.

The present invention was made in consideration of the above problems, and aims to provide a novel transmitting/receiving device.

To solve the above problems, the following measures are provided:

(1) The transceiver according to the first aspect includes a receiving device having a magnetic element including a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, and receiving an optical signal; a transmitting device having a modulated light output element and transmitting an optical signal; and a circuit chip having an integrated circuit electrically connected to the magnetic element and the modulated light output element.

(2) In the transceiver according to the above aspect, the magnetic element and the modulated light output element may be arranged perpendicular to the surface of the circuit chip.

(3) In the transceiver according to the above aspect, the position of the circuit chip in the direction perpendicular to the surface may be between the position of the magnetic element in the direction perpendicular to the surface and the position of the modulated light output element in the direction perpendicular to the surface.

(4) In the transceiver according to the above aspect, the position of the magnetic element in the perpendicular direction may be between the position of the modulated light output element in the perpendicular direction and the position of the circuit chip in the perpendicular direction.

(5) In the transceiver according to the above aspect, the position of the modulated light output element in the direction perpendicular to the surface may be between the position of the magnetic element in the direction perpendicular to the surface and the position of the circuit chip in the direction perpendicular to the surface.

(6) In the transceiver according to the above aspect, the magnetic element and the modulated light output element may be located on the first surface side of the circuit chip, and the magnetic element and the modulated light output element may not overlap each other when viewed from the direction perpendicular to the surface.

(7) In the transceiver according to the above aspect, the magnetic element and the integrated circuit may be electrically connected via a first through-wire that penetrates an insulating layer between the magnetic element and the integrated circuit, and the modulated light output element and the integrated circuit may be electrically connected via a second through-wire that penetrates an insulating layer between the modulated light output element and the integrated circuit.

(8) In the transceiver according to the above aspect, the modulated light output element and the integrated circuit may be electrically connected via a bump between the transmitter and the circuit chip.

(9) In the transceiver according to the above aspect, the transceiver may further include a wiring chip having wiring electrically connected to the magnetic element, the modulated light output element, and the integrated circuit, the magnetic element, the modulated light output element, and the circuit chip being on the first surface side of the wiring chip, and the modulated light output element, the modulated light output element, and the circuit chip may be configured not to overlap each other when viewed perpendicular to the surface of the wiring chip.

(10) In the transceiver according to the above aspect, the modulated light output element may be an optical modulation element.

(11) In the transceiver according to the above aspect, the optical modulation element may include a waveguide, and the waveguide may include lithium niobate.

(12) The transceiver according to the above aspect may further include an input section that irradiates the magnetic element with light containing a signal, an output section that outputs light containing a signal generated by the modulated light output element, a first fiber that connects the input section to the outside, and a second fiber that connects the output section to the outside.

The transmitter/receiver device described above is new and will create new breakthroughs.

1 is a conceptual diagram of a communication system according to a first embodiment. FIG. 2 is a cross-sectional view of the transmitting and receiving component according to the first embodiment. 1 is a cross-sectional view of a transmitting/receiving device according to a first embodiment. 3 is an enlarged cross-sectional view of a characteristic portion between the circuit chip and the transmitting device according to the first embodiment. FIG. FIG. 2 is a plan view of the receiving device according to the first embodiment. 1 is a cross-sectional view of a magnetic element according to a first embodiment. 5A to 5C are diagrams for explaining a first mechanism of a first operation example of the magnetic element according to the first embodiment. 10A to 10C are diagrams for explaining a second mechanism of the first operation example of the magnetic element according to the first embodiment. 10A to 10C are diagrams for explaining a first mechanism of a second operation example of the magnetic element according to the first embodiment. 10A to 10C are diagrams for explaining a second mechanism of a second operation example of the magnetic element according to the first embodiment. 13A to 13C are diagrams for explaining another example of the second operation example of the magnetic element according to the first embodiment. 13A to 13C are diagrams for explaining another example of the second operation example of the magnetic element according to the first embodiment. FIG. 2 is a plan view of an optical modulation element of the transmitting device according to the first embodiment. 1 is a cross-sectional view of a light modulation element according to a first embodiment. FIG. 11 is a cross-sectional view of a transceiver device according to a second embodiment. FIG. 11 is a cross-sectional view of a transceiver device according to a third embodiment. FIG. 11 is a cross-sectional view of a transceiver device according to a fourth embodiment. FIG. 13 is a plan view of a transceiver device according to a fourth embodiment. A cross-sectional view of a transceiver device according to a fifth embodiment. A cross-sectional view of a transceiver device according to a sixth embodiment. FIG. 13 is a plan view of a transceiver device according to a sixth embodiment. 13 is a cross-sectional view of another example of a transceiver device according to the sixth embodiment. FIG. A cross-sectional view of a transceiver device according to a seventh embodiment. FIG. 23 is a plan view of a transceiver device according to a seventh embodiment. This is another application example of a communication system. This is another application example of a communication system.

The following describes the embodiments in detail with reference to the drawings as appropriate. The drawings used in the following description may show characteristic parts in an enlarged scale for the sake of clarity, and the dimensional ratios of each component may differ from the actual ones. The materials, dimensions, etc. exemplified in the following description are merely examples, and the present invention is not limited to them. They may be modified as appropriate within the scope of the effects of the present invention.

The directions are defined. The surface on which the substrate 31 constituting the circuit chip 35 described later extends is the xy plane, one direction within the surface is the x direction, and the direction within the surface perpendicular to the x direction is the y direction. The direction perpendicular to the surface on which the substrate 31 extends is the z direction. Hereinafter, the +z direction may be expressed as "up" and the -z direction as "down". The +z direction is the direction from the substrate 31 toward the insulating layer 34. Up and down do not necessarily coincide with the direction in which gravity is applied.

"First embodiment"
FIG. 1 is a conceptual diagram of a communication system 200 according to a first embodiment. The communication system 200 shown in FIG. 1 includes a plurality of transmitting/receiving components 201 and a fiber 202 connecting the transmitting/receiving components 201. The communication system 200 can be used for short-distance or medium-distance communication such as within a data center or between data centers, or for long-distance communication such as between cities. The transmitting/receiving components 201 are installed, for example, in a data center or in a base station or backbone station of a long-distance communication network. The fiber 202 connects, for example, between data centers. The communication system 200 performs communication between the transmitting/receiving components 201, for example, via the fiber 202. The communication system 200 may perform communication between the transmitting/receiving components 201 wirelessly without using the fiber 202.

Figure 2 is a cross-sectional view of a transmitting/receiving component 201 according to the first embodiment. The transmitting/receiving component 201 includes a transmitting/receiving device 100, an input section 110, an output section 120, a first fiber 130, a second fiber 140, a connection section 150, and a housing 160.

The transmitting/receiving component 201 is connected to the fiber 202 via the connection part 150. The connection part 150 is formed in the housing 160 and is exposed to the outside.

The first fiber 130 connects the connection section 150 exposed to the outside and the input section 110. The first fiber 130 is, for example, an optical fiber. The input section 110 is in the traveling direction of the light output from the end of the first fiber 130. The input section 110 irradiates the light including the signal output from the end of the first fiber 130 to the receiving device 15 of the transmitting/receiving device 100. The input section 110 is, for example, a mirror, a lens, etc. The light sent from the fiber 202 to the transmitting/receiving part 201 is irradiated to the receiving device 15 via the first fiber 130 and the input section 110.

The second fiber 140 connects the connection section 150 exposed to the outside and the output section 120. The second fiber 140 is, for example, an optical fiber. The output section 120 is connected to the transmitting device 25 of the transmitting/receiving device 100. The output section 120 outputs light including a signal generated by the modulated light output element of the transmitting device 25. The output section 120 is, for example, a lens. The light output from the transmitting device 25 propagates to the fiber 202 via the output section 120 and the second fiber 140.

The transmitting/receiving device 100 is stored in a housing 160. The transmitting/receiving device 100 includes, for example, a receiving device 15, a transmitting device 25, and a circuit chip 35. The receiving device 15, the transmitting device 25, and the circuit chip 35 are stacked in the z direction.

Figure 3 is a cross-sectional view of the transmitting/receiving device 100 according to the first embodiment. The receiving device 15 and the transmitting device 25 are arranged in the z direction of the circuit chip 35. The receiving device 15 includes a magnetic element 10. The transmitting device 25 includes an optical modulation element 21. The magnetic element 10 and the optical modulation element 21 are arranged in the z direction of the circuit chip 35. The circuit chip 35 is between the receiving device 15 and the transmitting device 25 in the z direction. The position of the circuit chip 35 in the z direction is between the position of the magnetic element 10 in the z direction and the position of the optical modulation element 21 in the z direction. For example, the receiving device 15 (magnetic element 10) is on the first surface 35S1 side of the circuit chip 35, and the transmitting device 25 (optical modulation element 21) is on the second surface 35S2 side of the circuit chip 35. For example, the receiving device 15 (magnetic element 10) is disposed on the first surface 35S1 of the circuit chip 35, and the transmitting device 25 (light modulation element 21) is disposed on the second surface 35S2 of the circuit chip 35. The first surface 35S1 and the second surface 35S2 are surfaces of the circuit chip 35 that face each other in the z direction.

The receiving device 15 includes, for example, a plurality of magnetic elements 10 and an insulating layer 12. Although FIG. 3 shows an example in which the receiving device 15 includes a plurality of magnetic elements 10, the receiving device 15 may include only one magnetic element 10. The receiving device 15 receives an optical signal input to the receiving device 15 from the input unit 110, and converts the received optical signal into an electrical signal using the magnetic element 10. Details of the magnetic element 10 will be described later.

The insulating layer 12 covers the periphery of the magnetic element 10. The insulating layer 12 is, for example, an oxide, nitride, or oxynitride of Si, Al, or Mg. The insulating layer 12 is, for example, silicon oxide (SiO _x ), silicon nitride (SiN _x ), silicon carbide (SiC), chromium nitride, silicon carbonitride (SiCN), silicon oxynitride (SiON), aluminum oxide (Al ₂ O ₃ ), zirconium oxide (ZrO _x ), or the like.

The transmitting device 25 includes, for example, an optical modulation element 21. The transmitting device 25 transmits an optical signal modulated by the optical modulation element 21. The optical modulation element 21 includes a substrate 22, a covering layer 23, a waveguide 26, and an electrode 27. Details of the optical modulation element 21 will be described later. The transmitting device 25 is attached to the circuit chip 35, for example, by an adhesive layer 70.

The circuit chip 35 includes a substrate 31, electronic components 32, wiring 33, and an insulating layer 34. The circuit chip 35 controls the operation of the receiving device 15 and the transmitting device 25. The substrate 31 is a semiconductor substrate, for example, silicon. The electronic components 32 and wiring 33 are part of an integrated circuit 36. The integrated circuit 36 is electrically connected to the magnetic element 10 and the light modulation element 21. The electronic components 32 are, for example, transistors, capacitors, etc. The wiring 33 connects the electronic components 32, etc. The insulating layer 34 is an interlayer insulating layer, and the same material as the insulating layer 12 can be used. The insulating layer 34 covers the periphery of the electronic components 32 and wiring 33.

The magnetic element 10 is provided on the insulating layer 34. The integrated circuit 36 (electronic component 32 or wiring 33) of the circuit chip 35 and the magnetic element 10 of the receiving device 15 are electrically connected, for example, via a through-wire 50. The through-wire 50 extends in the z-direction. The through-wire 50 penetrates, for example, in the z-direction, an insulating layer between the magnetic element 10 and the integrated circuit 36 (for example, a part of the insulating layer 34, or a part of the insulating layer 34 and the insulating layer 12). The through-wire 50 connects the magnetic element 10 and the integrated circuit 36 (electronic component 32 or wiring 33).

The integrated circuit 36 of the circuit chip 35 and the light modulation element 21 of the transmitter 25 are electrically connected via, for example, a through-wire 60. The through-wire 60 extends in the z-direction. The through-wire 60 penetrates, for example, in the z-direction, an insulating layer (for example, an insulating substrate 22 and an adhesive layer 70) between the light modulation element 21 and the integrated circuit 36. The through-wire 60 connects the light modulation element 21 to the electronic component 32 or the wiring 33.

The transmitter 25 and the circuit chip 35 sandwiching the adhesive layer 70 may be electrically connected via bumps 63. FIG. 4 is an enlarged cross-sectional view of a characteristic portion between the circuit chip 35 and the transmitter 25 according to the first embodiment. The bumps 63 connect the through wiring 61 penetrating the substrate 31 of the circuit chip 35 and the through wiring 62 penetrating the substrate 22 of the transmitter 25. The bumps 63 are, for example, solder. The through wiring 61 electrically connects the integrated circuit 36 and the bumps 63. The through wiring 62 electrically connects the optical modulation element 21 and the bumps 63. The optical modulation element 21 and the integrated circuit 36 are electrically connected via the bumps 63 between the transmitter 25 and the circuit chip 35.

Figure 5 is a plan view of the receiving device 15 according to the first embodiment, seen from the z direction. The receiving device 15 converts the state or change in state of the irradiated light into an electrical signal. The receiving device 15 has, for example, multiple magnetic elements 10. Multiple magnetic elements 10 may be arranged within the spot sp of the irradiated light as shown in Figure 5, or only one magnetic element 10 may be arranged.

The light irradiated to the receiving device 15 is not limited to visible light, but also includes infrared light, which has a longer wavelength than visible light, and ultraviolet light, which has a shorter wavelength than visible light. The wavelength of visible light is, for example, 380 nm or more and less than 800 nm. The wavelength of infrared light is, for example, 800 nm or more and 1 mm or less. The wavelength of ultraviolet light is, for example, 200 nm or more and less than 380 nm. The light irradiated to the receiving device 15 is, for example, light that includes a high-frequency optical signal and whose intensity changes. The high-frequency optical signal is, for example, a signal having a frequency of 100 MHz or more.

When the state of light irradiated to each of the magnetic elements 10 changes, the voltage output from each of the magnetic elements 10 (the potential difference between the ends of each magnetic element in the z direction) changes in response to the change in the state of light. FIG. 6 is a cross-sectional view of the magnetic element 10 according to the first embodiment. The magnetic element 10 has, for example, a first ferromagnetic layer 1, a second ferromagnetic layer 2, a spacer layer 3, a first electrode 4, and a second electrode 5. 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. Light is irradiated to the magnetic element 10 from the first ferromagnetic layer 1 side.

The magnetic element 10 is, for example, a magnetic tunnel junction (MTJ) element in which the spacer layer 3 is made of an insulating material. In this case, the magnetic element 10 is an element in which the resistance value in the z direction (the resistance value when a current is passed in the z direction) changes according to the relative change between 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.

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 material 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, or an external magnetic field. The magnetization of the first ferromagnetic layer 1 changes state depending on the intensity of the light irradiated to the first ferromagnetic layer 1. The magnetization of a ferromagnetic material can change direction in response to a high-speed change in the intensity of the light irradiated to the ferromagnetic material (high-frequency optical signal). Therefore, by using the first ferromagnetic layer 1 as a light detection layer, the receiving device 15 can convert a high-frequency optical signal into an electrical signal, enabling high-speed optical communication.

The first ferromagnetic layer 1 includes a ferromagnetic material. In this specification, ferromagnetism includes ferrimagnetism. The first ferromagnetic layer 1 includes at least one of magnetic elements such as Co, Fe, or Ni. The first ferromagnetic layer 1 may include nonmagnetic elements such as B, Mg, Hf, and Gd in addition to the magnetic elements described above. The first ferromagnetic layer 1 may be, for example, an alloy including a magnetic element and a nonmagnetic element. The first ferromagnetic layer 1 may be composed of multiple layers. The first ferromagnetic layer 1 may be, for example, a CoFeB alloy, a laminate in which a CoFeB alloy layer is sandwiched between Fe layers, or a laminate in which a CoFeB alloy layer is sandwiched between CoFe layers.

The first ferromagnetic layer 1 may be an in-plane magnetized film with an easy axis of magnetization in the in-plane direction (any direction in the x-y plane) or a perpendicular magnetized film with an easy axis of magnetization in the direction perpendicular to the film plane (z-direction).

The thickness of the first ferromagnetic layer 1 is, for example, 1 nm or more and 5 nm or less. The thickness of the first ferromagnetic layer 1 is preferably, for example, 1 nm or more and 2 nm or less. When the first ferromagnetic layer 1 is a perpendicular magnetization film, if the thickness of the first ferromagnetic layer 1 is thin, the perpendicular magnetic anisotropy application effect from the layers above and below the first ferromagnetic layer 1 is strengthened, and the perpendicular magnetic anisotropy of the first ferromagnetic layer 1 is enhanced. In other words, if the perpendicular magnetic anisotropy of the first ferromagnetic layer 1 is high, the force that causes the magnetization to return to the z direction is strengthened. On the other hand, if the thickness of the first ferromagnetic layer 1 is thick, the perpendicular magnetic anisotropy application effect from the layers above and below the first ferromagnetic layer 1 is relatively weak, and the perpendicular magnetic anisotropy of the first ferromagnetic layer 1 is weakened.

When the thickness of the first ferromagnetic layer 1 is reduced, its volume as a ferromagnetic body is reduced, and when the thickness is increased, its volume as a ferromagnetic body is increased. The responsiveness of the magnetization 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. In other words, when the product of the magnetic anisotropy and the volume of the first ferromagnetic layer 1 is reduced, the responsiveness to light is increased. From this perspective, in order to increase the responsiveness 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.

If the thickness of the first ferromagnetic layer 1 is greater than 2 nm, an insertion layer made of, for example, Mo or W may be provided within the first ferromagnetic layer 1. In other words, the first ferromagnetic layer 1 may be a laminate in which a ferromagnetic layer, an insertion layer, and a ferromagnetic layer are stacked in this order in the z direction. The interfacial magnetic anisotropy at the interface between the insertion layer and the ferromagnetic layer enhances 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.

The second ferromagnetic layer 2 is a magnetization fixed layer. The magnetization fixed layer is a layer made of a magnetic material in which the state of magnetization 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. Also, for example, the magnitude of magnetization 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 may be an in-plane magnetization film or a perpendicular magnetization film.

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 laminate in which Co is 0.4 nm to 1.0 nm thick, Mo is 0.1 nm to 0.5 nm thick, a CoFeB alloy is 0.3 nm to 1.0 nm thick, and Fe is 0.3 nm to 1.0 nm thick, stacked in this order.

The magnetization of the second ferromagnetic layer 2 may be fixed, for example, by magnetic coupling with the third ferromagnetic layer via 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.

The third ferromagnetic layer is, for example, magnetically coupled to the second ferromagnetic layer 2. The magnetic coupling is, for example, an antiferromagnetic coupling, which occurs due to 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, etc.

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 made of a conductor, an insulator, or a semiconductor, or a layer containing a current-carrying point made of a conductor in an insulator. The 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.

For example, when the spacer layer 3 is made of an insulator, the magnetic element 10 has a magnetic tunnel junction (MTJ) consisting 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) effect. For example, when the spacer layer 3 is made of a metal, the magnetic element 10 can exhibit a giant magnetoresistance (GMR) effect. Such an element is called a GMR element. The magnetic element 10 may be called an MTJ element, a GMR element, or the like, depending on the material of the spacer layer 3, but is also collectively called a magnetoresistance effect element.

When the spacer layer 3 is made of an insulating material, a material containing aluminum oxide, magnesium oxide, titanium oxide, silicon oxide, or the like can be used. These insulating materials may also contain elements such as Al, B, Si, Mg, or magnetic elements such as Co, Fe, Ni. A high magnetoresistance change rate can be obtained by adjusting the thickness of the spacer layer 3 so that a high TMR effect is generated between the first ferromagnetic layer 1 and the second ferromagnetic layer 2. To efficiently utilize the TMR effect, the thickness of the spacer layer 3 may be about 0.5 to 5.0 nm, or about 1.0 to 2.5 nm.

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. To efficiently utilize the GMR effect, the thickness of the spacer layer 3 may be about 0.5 to 5.0 nm, or about 2.0 to 3.0 nm.

When the spacer layer 3 is made 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 thickness of the spacer layer 3 may be about 1.0 to 4.0 nm.

When a layer including a current-carrying point formed by a conductor in a nonmagnetic insulator is used as the spacer layer 3, the structure may include a current-carrying point formed by a nonmagnetic conductor such as Cu, Au, or Al in a nonmagnetic insulator made of aluminum oxide or magnesium oxide. The conductor may also be made of magnetic elements such as Co, Fe, or Ni. In this case, the film thickness of the spacer layer 3 may be about 1.0 to 2.5 nm. The current-carrying point is, for example, a columnar body with a diameter of 1 nm to 5 nm when viewed from a direction perpendicular to the film surface.

The magnetic element 10 may also have an underlayer, a cap layer, a perpendicular magnetization induction layer, and the like. The underlayer is located below the second ferromagnetic layer 2. The underlayer is a seed layer or a buffer layer. The seed layer enhances the crystallinity of the layer stacked on the seed layer. The seed layer is, for example, Pt, Ru, Hf, Zr, or NiFeCr. The thickness of the seed layer is, for example, 1 nm or more and 5 nm or less. The buffer layer is a layer that relieves lattice mismatch between different crystals. The buffer layer is, for example, Ta, Ti, W, Zr, Hf, or a nitride of these elements. The thickness of the buffer layer is, for example, 1 nm or more and 5 nm or less.

The cap layer is located above the first ferromagnetic layer 1. The cap layer prevents damage to the lower layer during the process and improves the crystallinity of the lower layer during annealing. The 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 of these.

The perpendicular magnetization induced layer is formed when the first ferromagnetic layer 1 is a perpendicular magnetization film. The perpendicular magnetization induced layer is laminated on the first ferromagnetic layer 1. The perpendicular magnetization induced layer induces perpendicular magnetic anisotropy in the first ferromagnetic layer 1. The perpendicular magnetization induced layer is, for example, magnesium oxide, W, Ta, Mo, etc. When the perpendicular magnetization induced layer is magnesium oxide, it is preferable that the magnesium oxide has oxygen deficiency in order to increase the conductivity. The film thickness of the perpendicular magnetization induced layer is, for example, 0.5 nm or more and 2.0 nm or less.

The first electrode 4 is in contact with, for example, the surface of the first ferromagnetic layer 1 opposite the spacer layer 3. The second electrode 5 is in contact with, for example, the surface of the second ferromagnetic layer 2 opposite the spacer layer 3. The first electrode 4 and the second electrode 5 sandwich the first ferromagnetic layer 1, the second ferromagnetic layer 2, and the spacer layer 3 in the z direction.

The first electrode 4 and the second electrode 5 are made of a conductive material. The first electrode 4 and the second electrode 5 are made of a metal such as Cu, Al, Au, or Ru. Ta or Ti may be laminated above and below these metals. The first electrode 4 and the second electrode 5 may also be a laminated film of Cu and Ta, a laminated film of Ta, Cu, and Ti, or a laminated film of Ta, Cu, and TaN. The first electrode and the second electrode may also be made of TiN or TaN.

The first electrode 4 and the second electrode 5 may be transparent to the wavelength range of light irradiated to the first ferromagnetic layer 1. For example, the first electrode 4 and the second electrode 5 may be transparent electrodes containing oxide transparent electrode materials such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), and indium gallium zinc oxide (IGZO). The first electrode 4 and the second electrode 5 may also be configured to have multiple columnar metals in these transparent electrode materials.

The magnetic element 10 is fabricated, for example, by a lamination process for each layer, an annealing process, and a processing process. Each layer is formed, for example, by sputtering. Annealing is performed, for example, at 250° C. or higher and 450° C. or lower. The laminated film is processed, for example, by photolithography and etching. The laminated film becomes a columnar magnetic element 10. The magnetic element 10 may be a cylinder or a prism. For example, the shortest width of the magnetic element 10 when viewed from the z direction may be 10 nm or higher and 2000 nm or lower, or 30 nm or higher and 500 nm or lower. The magnetic element 10 is obtained by the above processes.

The magnetic element 10 can be manufactured regardless of the material that constitutes the base. Therefore, the receiving device 15 can be manufactured directly on the circuit chip 35 without using an adhesive layer 70 or the like.

Figure 6 shows an example of a magnetic element 10, but the magnetic element may have a ferromagnetic material whose magnetization state changes when irradiated with light, and the resistance value may change with the change in magnetization state. For example, the magnetic element may be the tunnel magnetoresistance effect element or giant magnetoresistance effect element described above, as well as an anisotropic magnetoresistance (AMR) effect element, a colossal magnetoresistance (CMR) effect element, or the like.

Next, some examples of the operation of the magnetic element 10 will be described. The first ferromagnetic layer 1 is irradiated with light whose intensity changes. The resistance value in the z direction of the magnetic element 10 changes when the first ferromagnetic layer 1 is irradiated with light. The output voltage from the magnetic element 10 changes when the first ferromagnetic layer 1 is irradiated with light. In the first operation example, a case will be described in which the intensity of the light irradiated to the first ferromagnetic layer 1 has two levels, a first intensity and a second intensity. 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 be the case in which the intensity of the light irradiated to the first ferromagnetic layer 1 is zero.

Figures 7 and 8 are diagrams for explaining a first operation example of the magnetic element 10 according to the first embodiment. Figure 7 is a diagram for explaining a first mechanism of the first operation example, and Figure 8 is a diagram for explaining a second mechanism of the first operation example. In the upper graphs of Figures 7 and 8, the vertical axis represents the intensity of light irradiated to the first ferromagnetic layer 1, and the horizontal axis represents time. In the lower graphs of Figures 7 and 8, the vertical axis represents the resistance value of the magnetic element 10 in the z direction, and the horizontal axis represents time.

First, in a state where 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 parallel to each other, and the resistance value of the magnetic element 10 in the z direction indicates a first resistance value _R1 . The resistance value of the magnetic element 10 in the z direction is calculated by applying a sense current Is to the magnetic element 10 in the z direction, which generates a voltage across the magnetic element 10, and using Ohm's law from the voltage value. The output voltage from the magnetic element 10 is generated between the first electrode 4 and the second electrode 5. In the case of the example shown in FIG. 7, the sense current Is is applied from the first ferromagnetic layer 1 to the second ferromagnetic layer 2. By applying the sense current Is 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 and the magnetization M2 become parallel in the initial state. Furthermore, by passing the sense current Is in this direction, it is possible to prevent the magnetization M1 of the first ferromagnetic layer 1 from being reversed during operation.

Then, the intensity of the light irradiated to the first ferromagnetic layer 1 changes 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 its initial state. The state of the magnetization M1 of the first ferromagnetic layer 1 when 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 inclination angle with respect to the z direction, the magnitude, etc.

For example, as shown in FIG. 7, when the intensity of light irradiated to the first ferromagnetic layer 1 changes from a first intensity to a second intensity, the magnetization M1 tilts with respect to the z direction. Also, as shown in FIG. 8, when the intensity of light irradiated to the first ferromagnetic layer 1 changes from a first intensity to a second intensity, the magnitude of the magnetization M1 decreases. For example, when the magnetization M1 of the first ferromagnetic layer 1 tilts with respect to the z direction due to the irradiation intensity of light, the tilt angle is greater than 0° and less than 90°.

When the magnetization M1 of the first ferromagnetic layer 1 changes from the initial state, the resistance value in the z direction of the magnetic element 10 exhibits a second resistance value _R2 . The second resistance value _R2 is greater than the first resistance value _R1 . The second resistance value _R2 is between the resistance value when the magnetization M1 and the magnetization M2 are parallel (the first resistance value _R1 ) and the resistance value when the magnetization M1 and the magnetization M2 are antiparallel.

In the case shown in FIG. 7, the magnetization M1 of the first ferromagnetic layer 1 is subjected to a spin transfer torque in the same direction as the magnetization M2 of the second ferromagnetic layer 2. Therefore, the magnetization M1 tries to return to a parallel state with 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. In the case shown in FIG. 8, 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 returns to the original, and the magnetic element 10 returns to the initial state. In either case, the resistance value in the z direction of the magnetic element 10 returns to the first resistance value _R1 . In other words, 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 magnetic element 10 changes from the second resistance value _R2 to the first resistance value _R1 .

The resistance value in the z direction of the magnetic element 10 changes in response to changes in the intensity of the light irradiated to the first ferromagnetic layer 1. The output voltage from the magnetic element 10 changes in response to changes in the intensity of the light irradiated to the first ferromagnetic layer 1. In other words, the magnetic element 10 can convert changes in the intensity of the irradiated light into changes in the output voltage. In other words, the magnetic element 10 can convert a received optical signal into an electrical signal. The output voltage from the magnetic element 10 is sent to the integrated circuit 36, and the integrated circuit 36 processes, for example, the output voltage from the magnetic element 10 as a first signal (e.g., "1") when it is equal to or greater than a threshold value, and as a second signal (e.g., "0") when it is less than the threshold value.

Here, the case where magnetization M1 and magnetization M2 are parallel in the initial state have been described as an example, but magnetization M1 and magnetization M2 may be antiparallel in the initial state. In this case, the resistance value in the z direction of the magnetic element 10 decreases as the state of magnetization M1 changes (for example, as the angle change from the initial state of magnetization M1 increases). If the initial state is one in which magnetization M1 and magnetization M2 are antiparallel, it is preferable to flow the sense current Is from the second ferromagnetic layer 2 toward the first ferromagnetic layer 1. By flowing the sense current Is 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 magnetization M1 and magnetization M2 become antiparallel in the initial state.

In the first operation example, the light irradiated to the first ferromagnetic layer 1 has two levels of intensity, a first intensity and a second intensity, but in the second operation example, the intensity of the light irradiated to the first ferromagnetic layer 1 changes in multiple levels or in an analog manner.

Figures 9 and 10 are diagrams for explaining a second operation example of the magnetic element 10 according to the first embodiment. Figure 9 is a diagram for explaining a first mechanism of the second operation example, and Figure 10 is a diagram for explaining a second mechanism of the second operation example. In the upper graphs of Figures 9 and 10, the vertical axis represents the intensity of light irradiated to the first ferromagnetic layer 1, and the horizontal axis represents time. In the lower graphs of Figures 9 and 10, the vertical axis represents the resistance value of the magnetic element 10 in the z direction, and the horizontal axis represents time.

In the case of FIG. 9, when the intensity of the light irradiated to the first ferromagnetic layer 1 increases, the magnetization M1 of the first ferromagnetic layer 1 tilts from its initial state due to the external energy caused by the light irradiation. The angle between the direction of the magnetization M1 of the first ferromagnetic layer 1 when the first ferromagnetic layer 1 is not irradiated with light and the direction of the magnetization M1 when the first ferromagnetic layer 1 is irradiated with light is both greater than 0° and less than 90°.

When the magnetization M1 of the first ferromagnetic layer 1 is tilted from the initial state, the resistance value in the z direction of the magnetic element 10 changes. For example, 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 according to the tilt of the magnetization M1 of the first ferromagnetic layer 1. 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 . That is, the output voltage from the magnetic element 10 changes from the first voltage value to the second voltage value, the third voltage value, and the fourth voltage value according to the tilt of the magnetization M1 of the first ferromagnetic layer 1. The output voltage increases in the order of the first voltage value, the second voltage value, the third voltage value, and the fourth voltage value.

The resistance value of the magnetic element 10 in the z direction changes when the intensity of the light irradiated to the first ferromagnetic layer 1 changes. The output voltage from the magnetic element 10 changes when the intensity of the light irradiated to the first ferromagnetic layer 1 changes. For example, if the first voltage value is defined as "0", the second voltage value as "1", the third voltage value as "2", and the fourth voltage value as "3", the magnetic element 10 can output four values of information. Here, the case where four values are read out is shown as an example, but the number of values to be read out can be freely designed by setting the output voltage threshold. The magnetic element 10 may also output analog values as they are.

Similarly, in the case of FIG. 10, when the intensity of the light irradiated to the first ferromagnetic layer 1 increases, the magnitude of the magnetization M1 of the first ferromagnetic layer 1 decreases from the initial state due to the external energy caused by the light irradiation. When the magnetization M1 of the first ferromagnetic layer 1 decreases from the initial state, the resistance value in the z direction of the magnetic element 10 changes. For example, 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 according to the magnitude of the magnetization M1 of the first ferromagnetic layer 1. That is, the output voltage from the magnetic element 10 changes from the first voltage value to the second voltage value, the third voltage value, and the fourth voltage value according to the magnitude of the magnetization M1 of the first ferromagnetic layer 1. Therefore, similar to the case of FIG. 9, the magnetic element 10 can output the difference between these output voltages as multi-value or analog data.

In the second operating example, as in the first operating example, when the intensity of the light irradiated to the first ferromagnetic layer 1 returns to the first intensity, the state of the magnetization M1 of the first ferromagnetic layer 1 returns to its original state, and the magnetic element 10 returns to its initial state.

Here, we have taken the example of magnetization M1 and magnetization M2 being parallel in the initial state, but in the second operation example as well, magnetization M1 and magnetization M2 may be anti-parallel in the initial state.

In the first and second operation examples, the magnetizations M1 and M2 are parallel or anti-parallel in the initial state, but the magnetizations M1 and M2 may be perpendicular to each other in the initial state. For example, this case applies when the first ferromagnetic layer 1 is an in-plane magnetized film with magnetization M1 oriented in any direction in the xy plane, and the second ferromagnetic layer 2 is a perpendicular magnetized film with magnetization M2 oriented in the z direction. Due to magnetic anisotropy, magnetization M1 is oriented in any direction in the xy plane, and magnetization M2 is oriented in the z direction, so that magnetization M1 and magnetization M2 are perpendicular to each other in the initial state.

Figures 11 and 12 are diagrams for explaining another example of the second operation example of the magnetic element 10 according to the first embodiment. Figures 11 and 12 differ in the flow direction of the sense current Is applied to the magnetic element 10. In Figure 11, the sense current Is flows from the first ferromagnetic layer 1 to the second ferromagnetic layer 2. In Figure 12, the sense current Is flows from the second ferromagnetic layer 2 to the first ferromagnetic layer 1.

11 and 12, a sense current Is flows through the magnetic element 10, and a spin transfer torque acts on the magnetization M1 in the initial state. In the case of FIG. 11, the spin transfer torque acts so that the magnetization M1 is parallel to the magnetization M2 of the second ferromagnetic layer 2. In the case of FIG. 12, the spin transfer torque acts so that the magnetization M1 is antiparallel to the magnetization M2 of the second ferromagnetic layer 2. In both the cases of FIG. 11 and FIG. 12, in the initial state, the effect of magnetic anisotropy on the magnetization M1 is greater than the effect of the spin transfer torque, so the magnetization M1 is oriented in any direction within the xy plane.

When the intensity of the light irradiated to the first ferromagnetic layer 1 increases, the magnetization M1 of the first ferromagnetic layer 1 tilts from its initial state due to the external energy caused by the light irradiation. This is because the sum of the effect of the light irradiation and the effect of the spin transfer torque acting on the magnetization M1 becomes greater than the effect of the magnetic anisotropy related to the magnetization M1. When the intensity of the light irradiated to the first ferromagnetic layer 1 increases, the magnetization M1 in the case of FIG. 11 tilts to be parallel to the magnetization M2 of the second ferromagnetic layer 2, and the magnetization M1 in the case of FIG. 12 tilts to be antiparallel to the magnetization M2 of the second ferromagnetic layer 2. The tilt direction of the magnetization M1 in FIG. 11 and FIG. 12 is different because the direction of the spin transfer torque acting on the magnetization M1 is different.

When the intensity of the light irradiated to the first ferromagnetic layer 1 increases, the resistance value of the magnetic element 10 in the z direction decreases in the case of FIG. 11, and the resistance value of the magnetic element 10 in the z direction increases in the case of FIG. 12. In other words, when the intensity of the light irradiated to the first ferromagnetic layer 1 increases, the output voltage from the magnetic element 10 decreases in the case of FIG. 11, and the output voltage of the magnetic element 10 increases in the case of FIG. 12.

When the intensity of the light irradiated to the first ferromagnetic layer 1 returns to the first intensity, the state of the magnetization M1 of the first ferromagnetic layer 1 returns to its original state due to the effect of magnetic anisotropy on the magnetization M1. As a result, the magnetic element 10 returns to its initial state.

Here, an example has been described in which the first ferromagnetic layer 1 is an in-plane magnetized film and the second ferromagnetic layer 2 is a perpendicular magnetized film, but this relationship may be reversed. That is, in the initial state, magnetization M1 may be oriented in the z direction, and magnetization M2 may be oriented in any direction within the xy plane.

As described above, the receiving device 15 receives an optical signal and converts the received optical signal into an electrical signal using the magnetic element 10.

Figure 13 is a plan view of the light modulation element 21 of the transmitting device 25 according to the first embodiment, viewed from the z direction. Figure 14 is a cross-sectional view of the light modulation element 21 according to the first embodiment. Figure 14 is a cross-section taken along line A-A in Figure 13. The light modulation element 21 converts an electrical signal into an optical signal. The light modulation element 21 is an example of a modulated light output element. The light modulation element 21 shown in Figures 13 and 14 is an example of a light modulation element, and the configuration of the light modulation element is not limited to this example.

The optical modulation element 21 comprises a substrate 22, a coating layer 23, a waveguide 26, and an electrode 27.

The substrate 22 includes, for example, aluminum oxide. The substrate 22 is, for example, _{sapphire. The coating layer 23 is, for example, SiO2, Al2O3, MgF2, La2O3, ZnO, HfO2, MgO, Y2O3 , CaF2 , In2O3 , etc. , or a mixture thereof} .

The waveguide 26 has, for example, an input waveguide 26A, a branching portion 26B, a first waveguide 26C, a second waveguide 26D, a coupling portion 26E, and an output waveguide 26F.

The input waveguide 26A has an input end to which the input light L _in is input, and is connected to the branching portion 26B. The branching portion 26B is located between the input waveguide 26A and the first and second waveguides 26C and 26D. The input light L _in is input from the outside. The input light L _in is, for example, a laser beam.

The first waveguide 26C and the second waveguide 26D extend, for example, in the x direction. The lengths of the first waveguide 26C and the second waveguide 26D in the x direction are, for example, approximately the same.

The coupling portion 26E is located between the first and second waveguides 26C and 26D and the output waveguide 26F. The output waveguide 26F is connected to the coupling portion 26E and has an output end from which the output light L _out is output.

As shown in FIG. 14, the first waveguide 26C and the second waveguide 26D are composed of a part of the slab 28 and a ridge-shaped portion 28P. The slab 28 extends over the substrate 22. The ridge-shaped portion 28P protrudes from the upper surface of the slab 28. The slab 28 increases the electric field strength applied to the waveguide 26.

The slab 28 and the ridge-shaped portion 28P contain lithium niobate as the main component. Therefore, the waveguide 26 contains lithium niobate as the main component. Some elements of the lithium niobate may be replaced with other elements. The waveguide 26 is covered with, for example, a coating layer 23. The slab 28 and the ridge-shaped portion 28P may be made of something other than lithium niobate. For example, the slab 28 and the ridge-shaped portion 28P may be made of silicon or silicon oxide to which germanium oxide has been added, and the coating layer 23 may be silicon oxide. The input waveguide 26A, the branching portion 26B, the coupling portion 26E, and the output waveguide 26F are also configured in the same manner as the first waveguide 26C and the second waveguide 26D.

The electrode 27 includes, for example, electrodes 27A, 27B, and 27C. Electrodes 27A and 27B are located in positions that allow an electric field to be applied to at least a portion of the waveguide 26. An electric field can be applied to the first waveguide 26C from electrode 27A. An electric field can be applied to the second waveguide 26D from electrode 27B. Electrode 27A is, for example, above the first waveguide 26C. Electrode 27B is, for example, above the second waveguide 26D. Electrode 27C is, for example, to the side of electrodes 27A and 27B.

Electrodes 27A and 27B are connected to an integrated circuit 36 (electronic component 32 or wiring 33) of the circuit chip 35. Electrode 27C is connected to a reference potential. The reference potential is, for example, ground.

A voltage is applied to electrode 27A from integrated circuit 36. Integrated circuit 36 applies a modulated voltage to electrode 27A. A voltage is applied to electrode 27B from integrated circuit 36. Integrated circuit 36 applies a modulated voltage to electrode 27B. The voltage applied to electrode 27A and the voltage applied to electrode 27B can be controlled separately.

The input light L _in input from the input waveguide 26A branches and propagates in the first waveguide 26C and the second waveguide 26D. The phase difference between the light propagating in the first waveguide 26C and the light propagating in the second waveguide 26D is zero when the light branches.

When a voltage is applied between electrodes 27A and 27C, an electric field is applied to the first waveguide 26C, and the refractive index of the first waveguide changes due to the electro-optic effect. When a voltage is applied between electrodes 27B and 27C, an electric field is applied to the second waveguide 26D, and the refractive index of the second waveguide 26D changes due to the electro-optic effect.

When the first waveguide 26C and the second waveguide 26D have different refractive indices, a phase difference occurs between the light propagating through the first waveguide 26C and the light propagating through the second waveguide 26D. The lights propagating through the first waveguide 26C and the second waveguide 26D join together in the output waveguide 26F and are output from the optical modulation element 21 as the output light L _out .

The output light L _out is a result of the superposition of the light propagating through the first waveguide 26C and the light propagating through the second waveguide 26D. The intensity of the output light L _out varies according to the phase difference between the light propagating through the first waveguide 26C and the light propagating through the second waveguide 26D. For example, when the phase difference is an even multiple of π, the lights reinforce each other, so the intensity of the output light L _out increases, and when the phase difference is an odd multiple of π, the lights destructively interfere with each other, so the intensity of the output light L _out decreases. Based on this principle, the optical modulation element 21 modulates the input light L _in to the output light L _out in response to an electrical signal from the integrated circuit 36. The transmitting device 25 transmits the output light L _out modulated by the optical modulation element 21 as an optical signal.

In the transceiver 100 according to the first embodiment, the magnetic element 10 that converts the received optical signal into an electrical signal and the optical modulation element 21 that outputs an optical signal that is modulated light are electrically connected to an integrated circuit 36 that controls them, and the magnetic element 10 and the optical modulation element 21 are arranged in the z direction of the circuit chip 35. This allows the transceiver 100 according to the first embodiment to be miniaturized. In addition, the transceiver 100 according to the first embodiment can be handled as a single packaged electronic component, making it easy to connect it to other components such as the fiber 202.

The magnetic element 10 can be manufactured regardless of the material that constitutes the base, and can be manufactured on the circuit chip 35 without an adhesive layer 70 or the like. Therefore, the transceiver 100 according to the first embodiment can easily arrange the magnetic element 10 in the z direction of the circuit chip 35, and can be easily miniaturized.

Second Embodiment
15 is a cross-sectional view of a transmitting/receiving device 101 according to the second embodiment. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The transceiver 101 differs from the transceiver 100 according to the first embodiment in the stacking order of the receiver 15, transmitter 25, and circuit chip 35. In the transceiver 101, the circuit chip 35, receiver 15, and transmitter 25 are stacked in this order. The receiver 15 and transmitter 25 are on the first surface 35S1 side of the circuit chip 35. The magnetic element 10 and the light modulation element 21 are on the first surface 35S1 side of the circuit chip 35. The receiver 15 is between the circuit chip 35 and the transmitter 25 in the z direction. The position of the magnetic element 10 in the z direction is between the position of the circuit chip 35 in the z direction and the position of the light modulation element 21 in the z direction.

The waveguide 11 is located on one side of the receiving device 15. The waveguide 11 is located, for example, between the receiving device 15 and the transmitting device 25. One end of the waveguide 11 is in the traveling direction of the light output from the end of the first fiber 130. The light including the signal output from the end of the first fiber 130 propagates through the waveguide 11 and is irradiated to the magnetic element 10.

The transmitter 25 is bonded to the receiver 15, for example, with an adhesive layer 70. In the example shown in FIG. 15, the substrate 22 of the transmitter 25 and the waveguide 11 side of the receiver 15 are bonded to each other via an adhesive layer 70. The integrated circuit 36 of the circuit chip 35 and the optical modulation element 21 of the transmitter 25 are electrically connected to each other via a through-wire 60. The through-wire 60 penetrates the insulating layer (e.g., the insulating substrate 22, adhesive layer 70, insulating layer 12, and insulating layer 34) between the optical modulation element 21 and the integrated circuit 36, for example, in the z direction. The through-wire 60 connects the optical modulation element 21 and the integrated circuit 36. The optical modulation element 21 and the integrated circuit 36 may be electrically connected to each other via a bump between the transmitter 25 and the circuit chip 35, as in the first embodiment. In this case, the bump between the transmitter 25 and the circuit chip 35 is provided between the transmitter 25 and the receiver 15, sandwiching the adhesive layer 70.

The transceiver device 101 according to the second embodiment has the same effects as the transceiver device 100 according to the first embodiment.

"Third embodiment"
16 is a cross-sectional view of a transmitting/receiving device 102 according to the third embodiment. In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The transceiver 102 differs from the transceiver 100 according to the first embodiment in the stacking order of the receiver 15, transmitter 25, and circuit chip 35. In the transceiver 102, the circuit chip 35, transmitter 25, and receiver 15 are stacked in this order. The receiver 15 and transmitter 25 are on the second surface 35S2 side of the circuit chip 35. The magnetic element 10 and the light modulation element 21 are on the second surface 35S2 side of the circuit chip 35. The transmitter 25 is between the circuit chip 35 and the receiver 15 in the z direction. The position of the light modulation element 21 in the z direction is between the position of the circuit chip 35 in the z direction and the position of the magnetic element 10 in the z direction.

The transmitter 25 is attached to the circuit chip 35, for example, by an adhesive layer 70. In the example shown in FIG. 16, the substrate 22 of the transmitter 25 and the substrate 31 of the circuit chip 35 are attached to each other via an adhesive layer 70. The integrated circuit 36 of the circuit chip 35 and the light modulation element 21 of the transmitter 25 are electrically connected to each other via a through-wire 60. The through-wire 60 penetrates an insulating layer (for example, the insulating substrate 22, the adhesive layer 70, and the insulating substrate 31) between the light modulation element 21 and the integrated circuit 36, for example, in the z-direction. The through-wire 60 connects the light modulation element 21 and the integrated circuit 36. The light modulation element 21 and the integrated circuit 36 may be electrically connected to each other via a bump between the transmitter 25 and the circuit chip 35, as in the first embodiment. In this case, the bump between the transmitter 25 and the circuit chip 35 is provided between the substrate 22 and the substrate 31 sandwiching the adhesive layer 70.

The magnetic element 10 is provided, for example, on the coating layer 23 of the transmitting device 25. The integrated circuit 36 of the circuit chip 35 and the magnetic element 10 of the receiving device 15 are electrically connected via a through-wire 50. The through-wire 50 penetrates the insulating layers (for example, the insulating layer 12, the coating layer 23, the substrate 22, the adhesive layer 70, and the insulating layer 34) between the magnetic element 10 and the integrated circuit 36, for example, in the z-direction. The through-wire 50 connects the magnetic element 10 and the integrated circuit 36.

The transceiver device 102 according to the third embodiment has the same effects as the transceiver device 100 according to the first embodiment.

"Fourth embodiment"
Fig. 17 is a cross-sectional view of the transmitting/receiving device 103 according to the fourth embodiment. Fig. 18 is a plan view of the transmitting/receiving device 103 according to the fourth embodiment. In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The transmitting/receiving device 103 differs from the transmitting/receiving device 100 according to the first embodiment in the arrangement of the receiving device 15 and the transmitting device 25. The receiving device 15 and the transmitting device 25 are on the first surface 35S1 side of the circuit chip 35. The magnetic element 10 and the light modulation element 21 are on the first surface 35S1 side of the circuit chip 35. The receiving device 15 and the transmitting device 25 are arranged, for example, on the first surface 35S1 of the circuit chip 35. The receiving device 15 and the transmitting device 25 are located so as not to overlap each other when viewed from the z direction. The magnetic element 10 and the light modulation element 21 are arranged so as not to overlap each other when viewed from the z direction.

The transmitter 25 is bonded to the circuit chip 35, for example, by an adhesive layer 70. In the example shown in FIG. 17, the substrate 22 of the transmitter 25 and the insulating layer 34 of the circuit chip 35 are bonded to each other via the adhesive layer 70. The integrated circuit 36 of the circuit chip 35 and the light modulation element 21 of the transmitter 25 are electrically connected to each other via the through-wire 60. The through-wire 60 penetrates the insulating layer (for example, the insulating substrate 22, the adhesive layer 70, and the insulating layer 34) between the light modulation element 21 and the integrated circuit 36, for example, in the z direction. The through-wire 60 connects the light modulation element 21 and the integrated circuit 36. The light modulation element 21 and the integrated circuit 36 may be electrically connected to each other via a bump between the transmitter 25 and the circuit chip 35, as in the first embodiment. In this case, the bump between the transmitter 25 and the circuit chip 35 is provided between the substrate 22 and the insulating layer 34, sandwiching the adhesive layer 70.

The transceiver device 103 according to the fourth embodiment has the same effects as the transceiver device 100 according to the first embodiment.

Fifth Embodiment
19 is a cross-sectional view of a transmitting/receiving device 104 according to the fifth embodiment. In the fifth embodiment, the same components as those in the fourth embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The transmitting/receiving device 104 has a transmitting device 40 instead of the transmitting device 25 of the transmitting/receiving device 103 of the fourth embodiment. The transmitting device 40 is equipped with a modulated light output element. The modulated light output element of the fifth embodiment is an element that outputs modulated light by directly switching the light output ON and OFF by switching the power supply ON and OFF. The modulated light output element of the fifth embodiment is, for example, a laser diode, a light emitting diode (LED), etc. When the frequency of the optical signal output from the transmitting device 40 is about several MHz, a modulated light output element that directly switches ON and OFF can be sufficient.

The transceiver device 104 according to the fifth embodiment has the same effects as the transceiver device 100 according to the first embodiment.

Sixth Embodiment
Fig. 20 is a cross-sectional view of the transmitting/receiving device 105 according to the sixth embodiment. Fig. 21 is a plan view of the transmitting/receiving device 105 according to the sixth embodiment. In the sixth embodiment, the same components as those in the fourth embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The transmitting/receiving device 105 further includes a light source 80 in addition to the transmitting/receiving device 103 of the fourth embodiment. The light source 80 is arranged in the z direction of the circuit chip. The light source 80 is on the first surface 35S1 side of the circuit chip 35. The light source 80 is arranged, for example, on the first surface 35S1 of the circuit chip 35. The receiving device 15, the transmitting device 25, and the light source 80 are located so as not to overlap each other when viewed from the z direction. The magnetic element 10, the light modulation element 21, and the light source 80 are arranged so as not to overlap each other when viewed from the z direction.

The light source 80 outputs the input light L _in to be input to the light modulation element 21. The light source 80 is located to the side of the light modulation element 21. The light source 80 is, for example, a laser diode.

The transceiver 105 according to the sixth embodiment is packaged together with the light source 80. The transceiver 105 according to the sixth embodiment provides the same effects as the transceiver 100 according to the first embodiment.

Although FIG. 20 shows an example in which a light source 80 is incorporated in the transceiver 103 according to the fourth embodiment, the light source 80 may also be incorporated in the transceiver 100 to 102 according to the first to third embodiments. The light source 80 may be arranged on the same surface side as the surface of the circuit chip 35 on which the optical modulation element 21 is arranged. FIG. 22 is a modified example of the transceiver according to the fifth embodiment. The transceiver 105A shown in FIG. 22 is an example in which a light source 80 is incorporated in the transceiver 100 according to the first embodiment. In the example shown in FIG. 22, the light source 80 is on the second surface 35S2 side of the circuit chip 35.

Seventh Embodiment
Fig. 23 is a cross-sectional view of the transceiver 106 according to the seventh embodiment. Fig. 24 is a plan view of the transceiver 106 according to the seventh embodiment. In the seventh embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The transmitting/receiving device 106 includes a receiving device 15, a transmitting device 25, a circuit chip 35, a light source 80, and a wiring chip 90. The receiving device 15, the transmitting device 25, the light source 80, and the circuit chip 35 are on the first surface 90S1 side of the wiring chip 90. The magnetic element 10 and the light modulation element 21 are on the first surface 90S1 side of the wiring chip 90. The receiving device 15, the transmitting device 25, the light source 80, and the circuit chip 35 are arranged on the first surface 90S1 of the wiring chip 90. The receiving device 15, the transmitting device 25, the light source 80, and the circuit chip 35 are located so as not to overlap each other when viewed from the z direction. The magnetic element 10, the light modulation element 21, and the circuit chip 35 are arranged so as not to overlap each other when viewed from the z direction.

The wiring chip 90 includes wiring 91 and an insulating layer 92. The wiring chip 90 is electrically connected to each of the magnetic element 10, the light modulation element 21, the light source 80, and the integrated circuit 36 of the circuit chip 35 by through-wires 93. The wiring 91 and the through-wires 93 electrically connect each of the magnetic element 10, the light modulation element 21, and the light source 80 to the integrated circuit 36 of the circuit chip 35. The magnetic element 10 is connected to any of the wirings 91. The light modulation element 21 is connected to any of the wirings 91. The integrated circuit 36 (electronic component 32 or wiring 33) is connected to any of the wirings 91. The magnetic element 10, the light modulation element 21, and the light source 80 are controlled by the integrated circuit 36 of the circuit chip 35.

The transceiver 106 according to the seventh embodiment has the same effects as the transceiver 100 according to the first embodiment. Furthermore, the transceiver 106 according to the seventh embodiment can be packaged after each element is manufactured separately, making it easy to optimize each element.

The present invention is not limited to the above-mentioned embodiment and modified examples, and various modifications and variations are possible within the scope of the gist of the present invention as described in the claims. For example, the characteristic configurations of the above-mentioned embodiment and modified examples may be combined.

For example, in the fifth embodiment, an example was described in which a modulated light output element that directly switches the light output ON and OFF is used in place of the light modulation element 21 of the fourth embodiment, but a modulated light output element that directly switches the light output ON and OFF may be used in place of the light modulation element 21 of the first to third embodiments. Also, a modulated light output element that directly switches the light output ON and OFF may be used in place of the light modulation element 21 and light source 80 of the sixth and seventh embodiments.

Up to this point, the first to seventh embodiments have been used as examples in which the transmitting/receiving device is applied to the communication system 200 shown in FIG. 1, but the communication system is not limited to this case.

For example, FIG. 25 is a conceptual diagram of another example of a communication system. The communication system 300 shown in FIG. 25 is communication between two mobile terminal devices 301. The mobile terminal device 301 is, for example, a smartphone, a tablet, etc.

Each of the mobile terminal devices 301 includes the above-mentioned transmitting/receiving device 100. The transmitting/receiving device 100 may be any of the transmitting/receiving devices 101 to 106 other than those of the first embodiment. An optical signal transmitted from the transmitting device 25 of one mobile terminal device 301 is received by the receiving device 15 of the other mobile terminal device 301. The light used for transmission and reception between the mobile terminal devices 301 is, for example, visible light. Each receiving device 15 has a magnetic element, which converts the optical signal into an electrical signal.

For example, FIG. 26 is a conceptual diagram of another example of a communication system. The communication system 310 shown in FIG. 26 is communication between a mobile terminal device 301 and an information processing device 302. The information processing device 302 is, for example, a personal computer.

The mobile terminal device 301 includes a transmission/reception device 100, and the information processing device 302 includes a reception device 107. The transmission/reception device 100 may be any of the transmission/reception devices 101 to 106 other than those of the first embodiment. The information processing device 302 may include any of the transmission/reception devices 100 to 106 instead of the reception device 107. The optical signal transmitted from the transmission device 25 of the mobile terminal device 301 is received by the reception device 15 of the information processing device 302. The light used for transmission and reception between the mobile terminal device 301 and the information processing device 302 is, for example, visible light. Each reception device 15 has a magnetic element, which converts the optical signal into an electrical signal.

1...first ferromagnetic layer, 2...second ferromagnetic layer, 3...spacer layer, 4...first electrode, 5...second electrode, 10...magnetic element, 11...waveguide, 12...insulating layer, 15...receiving device, 21...optical modulation element, 22...substrate, 23...covering layer, 25...transmitting device, 26...waveguide, 27...electrode, 28...slab, 28P...ridge-shaped portion, 31...substrate, 32...electronic component, 33, 91...wiring, 34, 92...insulating layer, 35...circuit chip, 35S1, 90S1...first surface, 35S2...second surface, 36...integrated circuit, 40...transmitting device, 50, 60, 61, 62, 93...through wiring, 63...bump, 70...adhesive layer, 80...light source, 90...wiring chip, 100, 101, 102, 103, 104, 105, 105A, 106...transmitting/receiving device, 107...receiving device, 110...input section, 120...output section, 130...first fiber, 140...second fiber, 150...connecting section, 160...housing, 200, 300, 310...communication system, 201...transmitting/receiving component, 202...fiber, 301...portable terminal device, 302...information processing device

Claims (13)

a receiving device having a magnetic element including a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, the receiving device receiving an optical signal;
A transmitter having a modulated optical output element for transmitting an optical signal;
a circuit chip having an integrated circuit electrically connected to the magnetic element and the modulated light output element ;
A transceiver device , wherein an output voltage from the magnetic element changes in response to a change in intensity of the light irradiated to the first ferromagnetic layer when the first ferromagnetic layer is irradiated with light . The transceiver device according to claim 1, wherein the magnetic element and the modulated light output element are arranged perpendicular to the surface of the circuit chip. The transceiver according to claim 2, wherein the position of the circuit chip in the perpendicular direction is between the position of the magnetic element in the perpendicular direction and the position of the modulated light output element in the perpendicular direction. The transceiver according to claim 2, wherein the position of the magnetic element in the perpendicular direction is between the position of the modulated light output element in the perpendicular direction and the position of the circuit chip in the perpendicular direction. The transceiver according to claim 2, wherein the position of the modulated light output element in the perpendicular direction is between the position of the magnetic element in the perpendicular direction and the position of the circuit chip in the perpendicular direction. the magnetic element and the modulated light output element are on a first surface side of the circuit chip;
3. The transmitting/receiving device according to claim 2, wherein the magnetic element and the modulated light output element do not overlap each other when viewed from the direction perpendicular to the surface. the magnetic element and the integrated circuit are electrically connected via a first through-wire that penetrates an insulating layer between the magnetic element and the integrated circuit;
The transceiver device according to any one of claims 1 to 6, wherein the modulated light output element and the integrated circuit are electrically connected via a second through-hole wiring that penetrates an insulating layer between the modulated light output element and the integrated circuit. The transceiver according to any one of claims 2 to 7, wherein the modulated light output element and the integrated circuit are electrically connected via bumps between the transmitter and the circuit chip. a wiring chip having wiring electrically connected to the magnetic element, the modulated light output element, and the integrated circuit,
the magnetic element, the modulated light output element, and the circuit chip are located on a first surface side of the wiring chip;
2. The transmitting/receiving device according to claim 1, wherein said modulated light output element, said modulated light output element and said circuit chip do not overlap each other when viewed from a direction perpendicular to a surface of said wiring chip. The transceiver according to any one of claims 1 to 9, wherein the modulated light output element is an optical modulation element. The optical modulator includes a waveguide.
The transceiver of claim 10 , wherein the waveguide comprises lithium niobate. an input unit that irradiates the magnetic element with light containing a signal;
an output section for outputting light including a signal generated by the modulated light output element;
A first fiber connecting the input unit to the outside;
The transmitting/receiving device according to any one of claims 1 to 11, further comprising a second fiber connecting the output unit to an outside. a sense current is caused to flow from the first ferromagnetic layer to the second ferromagnetic layer when the magnetizations of the first ferromagnetic layer and the second ferromagnetic layer are parallel in a state where no light is irradiated;
A transceiver device as described in any one of claims 1 to 12, configured to flow a sense current from the second ferromagnetic layer to the first ferromagnetic layer when the magnetization of the first ferromagnetic layer and the magnetization of the second ferromagnetic layer are anti-parallel in a state in which no light is irradiated.