US-12628569-B2 - Light detection element having first and second ferromagnetic layers sandwiching spacer layer and receiving device

US12628569B2US 12628569 B2US12628569 B2US 12628569B2US-12628569-B2

Abstract

A light detection element include: a magnetic element, a capacitor, and a resistor, wherein the magnetic element and the capacitor are connected in series, the resistor is connected to the magnetic element and the capacitor in parallel, the magnetic element includes a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, and the magnetic element is configured to be irradiated with a light containing an optical signal with a change of intensity of the light.

Inventors

Tetsuya Shibata
Hideaki Fukuzawa
Tomohito Mizuno
Arata Tsukamoto
Yuichi KASATANI

Assignees

TDK CORPORATION

Dates

Publication Date: 20260512
Application Date: 20230412
Priority Date: 20220419

Claims (6)

1 . A light detection element comprising: a magnetic element, a capacitor, and a resistor, wherein the magnetic element and the capacitor are connected in series, the resistor is connected to the magnetic element and the capacitor in parallel, the magnetic element includes a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, and the magnetic element is configured to be irradiated with a light containing an optical signal with a change of intensity of the light; the light detection element further comprising a third electrode layer and a second dielectric body, wherein the magnetic element has a first surface and a second surface opposing each other in a laminating direction of the magnetic element, a position of the second dielectric body is between the third electrode layer and the second surface in the laminating direction, and the second dielectric body and the third electrode layer constitute at least a part of the capacitor; and the light detection element further comprising a second connecting via and a fourth electrode layer, wherein the resistor is connected to the third electrode layer branched off from the third electrode layer at a connecting part and the resistor is located between the connecting part and the second connecting via, and the fourth electrode layer is electrically connected to the first surface and the second connecting via, and electrically connected to the third electrode layer via the second connecting via and the resistor.
2 . The light detection element according to claim 1 , wherein the magnetic element is configured to be irradiated with the light from a side of the first surface.
3 . The light detection element according to claim 1 , further comprising a first electrode layer and a first dielectric body, wherein the magnetic element has a first surface and a second surface opposing each other in a laminating direction of the magnetic element, the first electrode layer is electrically connected to the first surface, a slit filled with the first dielectric body is provided in the first electrode layer, and the first dielectric body and the first electrode layer constitute at least a part of the capacitor.
4 . The light detection element according to claim 3 , further comprising a first connecting via and a second electrode layer, wherein the resistor is connected to the first electrode layer branched off from the first electrode layer at a connecting part, the resistor is located between the connecting part of the first electrode layer and the first connecting via, the slit is located between the magnetic element and the connecting part, and the second electrode layer is electrically connected to the second surface and the first connecting via, and electrically connected to the first electrode layer via the first connecting via and the resistor.
5 . The light detection element according to claim 3 , wherein the magnetic element is configured to be irradiated with the light from a side of the first surface.
6 . A receiving device comprising a magnetic element and a circuit, wherein the circuit includes a capacitor connected to the magnetic element in series, and a resistor connected to the magnetic element and the capacitor in parallel, wherein the magnetic element includes a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, the magnetic element is configured to be irradiated with a light containing an optical signal with a change of intensity of the light, the circuit is connected to the magnetic element and is configured to output a voltage with a magnitude corresponding to an amount of change per unit time of an output voltage output from the magnetic element according to the optical signal, and the receiving device is configured to receive the optical signal on a basis of the voltage output from the circuit; the receiving device further comprising a third electrode layer and a second dielectric body, wherein the magnetic element has a first surface and a second surface opposing each other in a laminating direction of the magnetic element, a position of the second dielectric body is between the third electrode layer and the second surface in the laminating direction, and the second dielectric body and the third electrode layer constitute at least a part of the capacitor; and the receiving device further comprising a second connecting via and a fourth electrode layer, wherein the resistor is connected to the third electrode layer branched off from the third electrode layer at a connecting part and the resistor is located between the connecting part and the second connecting via, and the fourth electrode layer is electrically connected to the first surface and the second connecting via, and electrically connected to the third electrode layer via the second connecting via and the resistor.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS This application relies for priority upon Japanese Patent Application No. 2022-068947 filed on Apr. 19, 2022, and Japanese Patent Application No. 2022-189938 filed on Nov. 29, 2022, the entire contents of which are hereby incorporated herein by reference for all purposes as if fully set forth herein. BACKGROUND The present disclosure relates to a light detection element and a receiving device. Communication traffic volumes have dramatically increased with the spread of the Internet, and the importance of optical communication has increased significantly. Optical communication involves communication means configured to convert an electric signal into an optical signal and perform transmission and reception using the optical signal. For example, Patent Document 1 discloses a receiving device configured to receive an optical signal using a photo diode. The photo diode is, for example, a p-n junction diode or the like using a p-n junction of a semiconductor. [Patent Document 1] Japanese Unexamined Patent Application, First Publication No. 2001-292107 SUMMARY While a light detection element using a p-n junction of a semiconductor is widely used, a new breakthrough is required for further development. In addition, there is a need to study a configuration that considers an actual use of the new light detection element. It is desirable to provide a novel light detection element and receiving device in consideration of actual use. The following means are provided. A light detection element including: a magnetic element, a capacitor, and a resistor, wherein the magnetic element and the capacitor are connected in series, the resistor is connected to the magnetic element and the capacitor in parallel, the magnetic element includes a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, and the magnetic element is configured to be irradiated with a light containing an optical signal with a change of intensity of the light. A light detection element including: a magnetic element, a resistor, and an inductor, wherein the magnetic element and the resistor are connected in series, the inductor is connected to the magnetic element and the resistor in parallel, the magnetic element includes a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, and the magnetic element is configured to be irradiated with a light containing an optical signal with a change of intensity of the light. A receiving device including a magnetic element and a circuit, wherein the magnetic element includes a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, the magnetic element is configured to be irradiated with a light containing an optical signal with a change of intensity of the light, the circuit is connected to the magnetic element and is configured to output a voltage with a magnitude corresponding to an amount of change per unit time of an output voltage output from the magnetic element according to the optical signal, and the receiving device is configured to receive the optical signal on a basis of the voltage output from the circuit. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a receiving device according to a first embodiment. FIG. 2 is a circuit diagram of a light detection element according to the first embodiment. FIG. 3 is a plan view of a feature portion of the light detection element according to the first embodiment. FIG. 4 is a cross-sectional view of the feature portion of the light detection element according to the first embodiment. FIG. 5 is a cross-sectional view of the feature portion of the light detection element according to the first embodiment. FIG. 6 is a view for describing a first mechanism of a first operation example of a magnetic element according to the first embodiment. FIG. 7 is a view for describing a second mechanism of the first operation example of the magnetic element according to the first embodiment. FIG. 8 is a graph showing a time change of an input voltage input to a CR circuit and an output voltage from the CR circuit. FIG. 9 shows a relation between a time change of an input voltage to the circuit according to the first embodiment and a time change of an output voltage from the light detection element according to the first embodiment. FIG. 10 is a view for describing a second operation example of the magnetic element according to the first embodiment. FIG. 11 is an example of an absolute value circuit according to the first embodiment. FIG. 12 is a plan view of a feature portion of a light detection element according to a second embodiment. FIG. 13 is a cross-sectional view of the feature portion of the light detection el