Detection and measurement devices

Abstract

To downsize a detection device that emits light to a living body and detects the light returned from the living body.SOLUTION: A detection device 3 includes: a semiconductor board 20; a first photoelectric conversion part 31 formed on the semiconductor board 20; a first light emitting layer 671 formed on the semiconductor board 20 in a laminated manner; and a first filter layer 32 formed on the first photoelectric conversion part in a laminated manner.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a detection device and a measurement device that include a light-emitting unit and a light-receiving unit. [Background technology]

[0002] Various measurement techniques for non-invasively measuring biological information such as pulse waves have been proposed. Patent documents 1 and 2 describe detection devices that include a light-emitting unit that emits light toward a living body and a light-receiving unit that receives light reflected from the living body. By analyzing the signal output from the light-receiving unit of this type of detection device, biological information can be obtained.

[0003] The detection device (detection element) in Patent Document 1 includes a substrate on which a light source (organic EL element or LED) is mounted as a light-emitting unit. On the substrate, a photodiode, phototransistor, photoconductive cell, image sensor, or the like is mounted as a light-receiving unit adjacent to the light source.

[0004] The detection device (optical sensor module) in Patent Document 2 uses a flexible printed circuit board as a substrate on which a light-emitting unit and a light-receiving unit are arranged. The light-emitting unit is an LED, and the light-receiving unit is a photodiode. By using a flexible printed circuit board, the substrate can be made thinner, thereby enabling the detection device to be made thinner. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2018-149157 [Patent Document 2] Japanese Patent Application Publication No. 2018-042597 Summary of the Invention [Problem to be solved by the invention]

[0006] In the detection devices described in Patent Documents 1 and 2, the LED used as the light-emitting unit and the photodiode used as the light-receiving unit are each made into chips and can be handled as components. Therefore, when mounting them on the surface of a substrate, a certain clearance must be provided between the light-emitting unit and the light-receiving unit depending on the mounting accuracy of the chip. This places a limit on how small the detection device can be. [Means for solving the problem]

[0007] In order to solve the above problems, the detection device of the present invention includes a semiconductor substrate, a first photoelectric conversion unit formed on the semiconductor substrate, a first light-emitting layer formed by being laminated on the semiconductor substrate, and a first filter layer formed by being laminated on the first photoelectric conversion unit; a light-emitting section formed on a first surface of the semiconductor substrate and emitting light toward a living body; and a light-receiving section formed on the first surface at a position adjacent to the light-emitting section and receiving light from the living body, wherein the light-receiving section comprises the first photoelectric conversion section formed within a layer of the semiconductor substrate and the first filter layer formed on the surface of the first photoelectric conversion section, and the light-emitting section comprises a first light-emitting element at least a portion of which is disposed at the same position as the first filter layer in a normal direction of the semiconductor substrate, and the first light-emitting element comprises a first electrode, a light-transmitting second electrode facing the first electrode from the opposite side to the semiconductor substrate, and the first light-emitting layer formed between the first electrode and the second electrode. .

[0008] A measuring device of the present invention comprises the above-described detecting device and an information analyzing unit that identifies biological information from a detection signal that indicates a detection result by the detecting device. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a side view of a measuring device to which the present invention is applied. [Figure 2] 1 is a block diagram showing the functional configuration of a measurement device to which the present invention is applied. [Figure 3] FIG. 2 is a plan view schematically showing the planar shapes of a light receiving section and a light emitting section. [Figure 4] FIG. 2 is a cross-sectional view schematically showing the cross-sectional configuration of a light receiving section and a light emitting section. [Figure 5] 10 is a cross-sectional view schematically showing the cross-sectional configuration of a light receiving section and a light emitting section when each light emitting element is provided with a color filter. FIG. [Figure 6] 10 is a cross-sectional view that schematically shows the cross-sectional configuration of a light receiving section and a light emitting section when an angle limiting filter layer is omitted. FIG. [Figure 7] FIG. 10 is a plan view schematically showing the planar shapes of a light receiving section and a light emitting section of a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, each component is illustrated in a schematic manner so that it can be recognized, and the actual dimensions and proportions may differ from those shown in the drawings.

[0011] <Measuring equipment> FIG. 1 is a side view of a measuring device 100 to which the present invention is applied. The measuring device 100 is a biometric measuring device that non-invasively measures biometric information. The measuring device 100 is used by pointing it at a part of the body (living body) of a subject to be measured (hereinafter referred to as "measurement part M"). In the example shown in FIG. 1, the measuring device 100 is a wristwatch-type portable device equipped with a housing 1 and a strap 2. The measurement part M is the subject's wrist. The measuring device 100 is used by wrapping the band-shaped strap 2 around the subject's wrist so that the detection surface 10 of the housing 1 faces the skin surface of the wrist (measurement part M).

[0012] In this specification, the X, Y, and Z directions are perpendicular to each other. The Z direction is the normal direction of the detection surface 10. The +Z direction is the direction from the detection surface 10 toward the measurement site M, and the -Z direction is the direction from the measurement site M toward the detection surface 10.

[0013] In this specification, the subject's pulse wave (e.g., pulse rate) and oxygen saturation (SpO2) are exemplified as biological information. The pulse wave refers to the time change in the volume of blood vessels linked to the heartbeat. The oxygen saturation refers to the percentage of hemoglobin in the subject's blood that is bound to oxygen, and is an index for evaluating the subject's respiratory function.

[0014] Fig. 2 is a block diagram showing the functional configuration of a measuring device 100 to which the present invention is applied. As shown in Fig. 2, the measuring device 100 includes a control device 5, a storage device 6, a display device 4, and a detection device 3. The control device 5 and the storage device 6 are arranged inside a housing 1. The detection device 3 is arranged on a detection surface 10. The display device 4 is arranged on the surface of the housing 1 opposite to the detection surface 10. The display device 4 displays various images including measurement results under the control of the control device 5. The display device 4 is, for example, a liquid crystal display panel.

[0015] 2, the measuring device 100 may be configured to include an operation unit such as operation buttons or a touch panel arranged on the surface of the housing 1, and to input operation signals corresponding to operations on the operation unit to the control device 5. The measuring device 100 may also include a communication unit for outputting the measurement results to the outside and inputting signals from the outside to the control device 5. Alternatively, the measuring device 100 may include an audio output unit or a vibration unit as means for notifying the measurement results.

[0016] 2, the detection device 3 includes a light receiving unit 11, a light emitting unit 12, a drive circuit 13, and an output circuit 14. Note that it is also possible to install one or both of the drive circuit 13 and the output circuit 14 as external circuits of the detection device 3. In other words, the drive circuit 13 and the output circuit 14 can be omitted from the detection device 3.

[0017] The detection device 3 is a reflective optical sensor module that emits light from a detection surface 10, receives light incident on the detection surface 10 from a measurement site M, and generates a detection signal S. That is, in the detection device 3 of this embodiment, a light receiving unit 11 and a light emitting unit 12 are arranged on the detection surface 10. The light emitting unit 12 has a first light emitting element 121, a second light emitting element 122, and a third light emitting element 123. The first light emitting element 121, the second light emitting element 122, and the third light emitting element 123 are, respectively, a detection element. Light of different wavelengths is emitted from the exit surface 10.

[0018] The first light emitting element 121 emits a first light LG. The first light LG is, for example, green light having a green wavelength band of 520 nm to 550 nm and a peak wavelength of 520 nm. The second light emitting element 122 emits a second light LR. The second light LR is, for example, red light having a red wavelength band of 600 nm to 800 nm and a peak wavelength of 660 nm. The third light emitting element 123 emits a third light LI. The third light LI is, for example, near-infrared light having a near-infrared wavelength band of 800 nm to 1300 nm. The third light LI is, for example, light having a peak wavelength of 905 nm. Note that the wavelength of the light emitted by each light emitting element is not limited to the above wavelength bands.

[0019] The drive circuit 13 supplies a drive current to cause each of the first light-emitting element 121, the second light-emitting element 122, and the third light-emitting element 123 to emit light. For example, the drive circuit 13 causes each of the first light-emitting element 121, the second light-emitting element 122, and the third light-emitting element 123 to emit light periodically in a time-division manner. The light emitted from each of the first light-emitting element 121, the second light-emitting element 122, and the third light-emitting element 123 enters the measurement site M from the detection surface 10, propagates while being repeatedly reflected and scattered within the measurement site M, and then exits the measurement site M and enters the light-receiving unit 11 arranged on the detection surface 10.

[0020] The light receiving section 11 has a first light receiving section 111 and a second light receiving section 112. The first light receiving section 111 and the second light receiving section 112 each generate a detection signal according to the intensity of the received light.

[0021] The first light receiving unit 111 receives the first light LG emitted from the first light emitting element 121 and propagated inside the measurement site M, and generates a detection signal according to the intensity of the received light. The second light receiving unit 112 receives the second light LR emitted from the second light emitting element 122 and propagated inside the measurement site M, or the third light LI emitted from the third light emitting element 123 and propagated inside the measurement site M, and generates a detection signal according to the intensity of the received light.

[0022] The output circuit 14 is configured to include, for example, an A / D converter that converts the detection signals generated by the first light receiving unit 111 and the second light receiving unit 112 from analog to digital, and an amplifier circuit that amplifies the converted detection signals (both not shown), and generates multiple detection signals S (S1, S2, S3) corresponding to different wavelengths.

[0023] The detection signal S1 is a signal representing the intensity of light received by the first light receiving unit 111 when receiving the first light LG (green light) emitted from the first light emitting element 121. The detection signal S2 is a signal representing the intensity of light received by the second light receiving unit 112 when receiving the second light LR (infrared light) emitted from the second light emitting element 122. The detection signal S3 is a signal representing the intensity of light received by the second light receiving unit 112 when receiving the third light LI (near-infrared light) emitted from the third light emitting element 123.

[0024] Generally, the amount of light absorbed by blood differs when blood vessels are dilated and when they are contracted, so each detection signal S becomes a pulse wave signal that includes a periodic fluctuation component corresponding to the pulsation component (volume pulse wave) of the artery inside the measurement site M.

[0025] The drive circuit 13 and the output circuit 14 are mounted on a substrate, for example, in the form of an IC chip. As will be described later, in this embodiment, the light receiving unit 11 and the light emitting unit 12 are formed on the same semiconductor substrate 20 (see FIGS. 3 and 4). The drive circuit 13 and the output circuit 14 are mounted on a circuit arrangement section of the semiconductor substrate 20 on which the light receiving unit 11 and the light emitting unit 12 are formed. Note that the drive circuit 13 and the output circuit 14 may be mounted on a substrate separate from the semiconductor substrate 20 on which the light receiving unit 11 and the light emitting unit 12 are formed. Alternatively, as described above, the drive circuit 13 and the output circuit 14 can be installed as external circuits of the detection device 3.

[0026] The control device 5 is an arithmetic processing device such as a CPU (Central Processing Unit) or FPGA (Field-Programmable Gate Array), and controls the entire measuring device 100. The storage device 6 is composed of, for example, a non-volatile semiconductor memory, and stores programs executed by the control device 5 and various data used by the control device 5. Note that the functions of the control device 5 may be distributed across multiple integrated circuits, or some or all of the functions of the control device 5 may be implemented by dedicated electronic circuits. Note that, although the control device 5 and the storage device 6 are illustrated as separate elements in FIG. 2, the control device 5 incorporating the storage device 6 may also be implemented by, for example, an ASIC or the like.

[0027] The control device 5 executes a program stored in the storage device 6 to identify the subject's biological information from the multiple detection signals S (S1, S2, S3) generated by the detection device 3. Specifically, the control device 5 identifies the subject's pulse wave from the detection signal S1 representing the intensity of the first light LG (green light) received by the first light receiving unit 111. The control device 5 can identify the subject's pulse rate, for example, based on the detection signal S1. The control device 5 can also identify the subject's oxygen saturation (SpO2) by analyzing the detection signal S2 representing the intensity of the second light LR (red light) received by the light receiving unit 11 and the detection signal S3 representing the intensity of the third light LI (near-infrared light) received by the light receiving unit 11.

[0028] As described above, the control device 5 functions as an information analysis unit that identifies biological information from the detection signal S that indicates the detection result by the detection device 3. The control device (information analysis unit) 5 displays the biological information identified from the detection signal S on the display device 4. It is also possible to notify the user of the measurement results by audio output. It is also possible to notify the user of a warning (possible impairment of physical function) if the pulse rate or oxygen saturation level fluctuates to a value outside a predetermined range.

[0029] <Detailed configuration of the light-emitting unit and light-receiving unit> FIG. 3 is a plan view schematically showing the planar shapes of the light receiving section 11 and the light emitting section 12. FIG. 4 is a cross-sectional view schematically showing the cross-sectional configuration of the light receiving section 11 and the light emitting section 12 of FIG. 3, taken along the line AA in FIG. 3. In this embodiment, the light receiving section 11 and the light emitting section 12 are formed on the same semiconductor substrate 20. The semiconductor substrate 20 is made of a semiconductor material such as silicon (Si) and is used as a base (underlying layer) on which the light receiving section 11 and the light emitting section 12 are formed. As shown in FIG. 4, the light receiving section 11 and the light emitting section 12 are formed on a first surface 21 of the semiconductor substrate 20. The first surface 21 is a surface facing the +Z direction. The light receiving section 11 and the light emitting section 12 are formed adjacent to each other on the first surface 21.

[0030] As described above, the light receiving unit 11 includes the first light receiving unit 111 and the second light receiving unit 112. As shown in FIG. 4, the first light receiving unit 111 is formed in a position adjacent to the light emitting unit 12. The second light receiving unit 112 is disposed on the opposite side of the first light receiving unit 111 from the light emitting unit 12. Therefore, the second light receiving unit 112 is farther from the light emitting unit 12 than the first light receiving unit 111.

[0031] 3, in this embodiment, the light receiving unit 11 is rectangular. The light receiving unit 11 has a shape in which the second light receiving unit 112 is disposed in the center, and the first light receiving unit 111 surrounds the outer periphery of the second light receiving unit 112 in a strip shape with a constant width. The light receiving unit 11 includes an anode electrode 113 and a cathode electrode 114 corresponding to the first light receiving unit 111, and an anode electrode 115 and a cathode electrode 116 corresponding to the second light receiving unit 112. These electrodes are electrically connected to terminals C1, C2, C3, and C4 disposed on the outside of the light receiving unit 11 and the light emitting unit 12, respectively, via wiring formed in the angle limiting filter layer 35, which will be described later.

[0032] The light-emitting section 12 has a shape that surrounds the outer periphery of the light-receiving section 11. The first light-emitting element 121 that emits the first light LG (green light) is arranged in the inner periphery of the light-emitting section 12, and surrounds the outer periphery of the light-receiving section 11 in a strip shape with a constant width. The second light-emitting element 122 that emits the second light LR (red light) is arranged in the inner periphery of the first light-emitting element 121. The third light-emitting element 123 that emits the third light LI (near-infrared light) is arranged in the peripheral region of the light-emitting unit 12, and surrounds the outer periphery of the second light-emitting element 122 in a band shape with a constant width. Therefore, the second light-emitting element 122 is farther from the light-receiving unit 11 than the first light-emitting element 121. The third light-emitting element 123 is farther from the light-receiving unit 11 than the second light-emitting element 122.

[0033] The light-emitting unit 12 includes anode contacts 126, 127, and 128 corresponding to the first light-emitting element 121, the second light-emitting element 122, and the third light-emitting element 123, respectively, and a common cathode contact 129. The anode contacts 126, 127, and 128 and the cathode contact 129 are electrically connected to terminals D1, D2, D3, and D4 arranged outside the light-receiving unit 11 and the light-emitting unit 12, respectively, via wiring formed in a wiring layer 61, which will be described later.

[0034] <Cross-sectional structure of the light receiving section> 4, the first light receiving section 111 includes a first photoelectric conversion section 31 formed within a layer of the semiconductor substrate 20, and a first filter 32 formed by being laminated on the surface of the first photoelectric conversion section 31 in the +Z direction. The second light receiving section 112 includes a second photoelectric conversion section 33 formed at a position adjacent to the first photoelectric conversion section 31 within the layer of the semiconductor substrate 20, and a second filter layer 34 formed by being laminated on the surface of the second photoelectric conversion section 33. The second photoelectric conversion section 33 is farther from the light emitting section 12 than the first photoelectric conversion section 31.

[0035] Each of the first photoelectric conversion unit 31 and the second photoelectric conversion unit 33 includes a photodiode such as a PIN-type photodiode or a PN-type photodiode, or a phototransistor. In the example shown in Fig. 4, each of the first photoelectric conversion unit 31 and the second photoelectric conversion unit 33 includes an n-type semiconductor layer 41 embedded in the semiconductor substrate 20, a p-type semiconductor layer 42 formed inside the n-type semiconductor layer 41, and an n-type semiconductor layer 43 embedded inside the p-type semiconductor layer 42. The p-type semiconductor layer 42 is exposed on the first surface 21 of the semiconductor substrate 20, and forms a light-receiving surface 44 onto which light passing through the first filter layer 32 or the second filter layer 34 is incident.

[0036] The first photoelectric conversion section 31 and the second photoelectric conversion section 33 are embedded in a surface layer on the first surface 21 side of the semiconductor substrate 20. The light-receiving surface 44 of the first photoelectric conversion section 31 and the light-receiving surface 44 of the second photoelectric conversion section 33 are located on the same plane as the first surface 21 of the semiconductor substrate 20. The first filter layer 32 and the second filter layer 34 are located in the +Z direction with respect to the first surface 21.

[0037] An angle limiting filter layer 35 is formed on the first surface 21 of the semiconductor substrate 20 over the entire area where the first photoelectric conversion section 31 and the second photoelectric conversion section 33 are arranged. The angle limiting filter layer 35 has a first region 351 that overlaps the first photoelectric conversion section 31, and a second region 352 that overlaps the second photoelectric conversion section 33. Light-blocking materials that constitute the angle limiting filter 36 are arranged within the layers of the first region 351 and the second region 352, respectively.

[0038] The first filter layer 32 has a layer structure in which a bandpass filter layer 37 is laminated on the surface of a first region 351 in the angle limiting filter layer 35. The second filter layer 34 is made up of only the second region 352 of the angle limiting filter layer 35. In other words, the first light receiving section 111 and the second light receiving section 112 are identical in configuration except that the first light receiving section 111 has a bandpass filter layer 37 and the second light receiving section 112 does not have a bandpass filter layer 37.

[0039] For example, the angle limiting filter layer 35 includes a conductive layer 51 made of a light-reflecting material such as an aluminum copper alloy (AlCu) alloy or titanium nitride (TIN), an interlayer insulating film 52 made of a light-transmitting material such as silicon dioxide (SiO2) or silicon nitride (SiN), and a light shielding body 53 formed inside the interlayer insulating film 52. The light shielding body 53 is, for example, a conductive plug made of a light-absorbing material such as tungsten (W). 6 includes a conductive layer 51 and a light shielding body 53 arranged to form an opening 54 that overlaps with a light receiving surface 44 formed by a p-type semiconductor layer 42, and the light shielding body 53 arranged in a columnar shape inside the opening 54.

[0040] Due to the arrangement of the conductive layer 51 and the light shielding body 53, the angle limiting filter 36 has the property of transmitting light incident at angles smaller than a predetermined incident angle (hereinafter referred to as the allowable incident angle) and cutting light incident at angles larger than the allowable incident angle. Therefore, the first filter layer 32 limits the incident angle of light incident on the light receiving surface 44 of the first photoelectric conversion section 31. Furthermore, the second filter layer 34 limits the incident angle of light incident on the light receiving surface 44 of the second photoelectric conversion section 33. Therefore, the detection device 3 can transmit light that propagates within the living body and then enters the detection surface 10 of the detection device 3 at the allowable incident angle, and can cut light that enters at an angle larger than the allowable incident angle, such as external light such as sunlight or light that did not enter the living body.

[0041] A portion of the conductive layer 51 and the light shielding body 53 (conductive plug) arranged in the angle limiting filter layer 35 constitutes wiring electrically connected to the anode electrode 113 and the cathode electrode 114 of the first photoelectric conversion section 31, and wiring electrically connected to the anode electrode 115 and the cathode electrode 116 of the second photoelectric conversion section 33.

[0042] The bandpass filter layer 37 includes a multilayer film 58 formed by alternately stacking thin films made of a low-refractive index material such as silicon dioxide (SiO2) and thin films made of a high-refractive index material such as titanium dioxide (TiO2), and a light-shielding wall 59 surrounding the periphery of the multilayer film 58. The light-shielding wall 59 blocks, for example, the second light LR (red light) and the third light LI (near-infrared light). Note that the light-shielding wall 59 may be omitted. The multilayer film 58 has the property of selectively transmitting the wavelength band of the first light LG (green light) and absorbing and cutting the second light LR (red light) and the third light LI (near-infrared light), which are light in other wavelength bands.

[0043] <Cross-sectional structure of the light-emitting part> As shown in FIG. 4, the light-emitting section 12 includes a wiring layer 61 formed on the first surface 21 of the semiconductor substrate 20, an organic EL element forming section 62 formed on the surface of the wiring layer 61, and a sealing layer 63 covering the entire area of ​​the organic EL element forming section 62 and its periphery from the +Z direction. The sealing layer 63 is made of a light-transmitting inorganic material such as silicon dioxide (SiO2) or silicon oxynitride (SiON). The sealing layer 63 may contain other materials to the extent that the sealing performance is not impaired. The light-emitting section 12 also includes a reflective layer 64 disposed within the wiring layer 61. The reflective layer 64 is made of a light-reflective material such as an aluminum-copper alloy (AlCu).

[0044] 4, the wiring layer 61 extends to the outer periphery of the sealing layer 63 on the first surface 21 of the semiconductor substrate 20. Terminals D1, D2, D3, and D4 (see FIG. 3) connected to the light-emitting unit 12 and terminals C1, C2, C3, and C4 (see FIG. 3) connected to the light-receiving unit 11 are formed on the surface of the wiring layer 61 extending to the outer periphery of the sealing layer 63.

[0045] The wiring layer 61 includes a conductive layer 55 made of a material such as aluminum copper alloy (AlCu) or titanium nitride (TIN), an interlayer insulating film 56 made of an optically transparent material such as silicon dioxide (SiO2) or silicon nitride (SiN), and a conductive plug 57 made of a material such as tungsten (W).

[0046] 4, the plurality of interlayer insulating films 56 constituting the wiring layer 61 are each formed in the same layer as the interlayer insulating film 52 constituting the angle limiting filter layer 35, and the interlayer insulating films 56, 52 are formed to form a continuous layer. Also, the conductive layer 55 provided in the wiring layer 61 is formed in the same layer as the conductive layer 51 provided in the angle limiting filter layer 35. Therefore, The angle limiting filter layer 35 and the wiring layer 61 can be formed on the semiconductor substrate 20 in the same process. Note that the layer configuration of the wiring layer 61 and the angle limiting filter layer 35 is not limited to the configuration shown in FIG.

[0047] 4, the wiring layer 61 and the angle limiting filter layer 35 are at approximately the same position and height in the Z direction. The organic EL element forming section 62 is formed on the surface of the wiring layer 61, and the height (thickness) in the Z direction of the organic EL element forming section 62 is smaller than the height (thickness) in the Z direction of the bandpass filter layer 37. Therefore, the first light emitting element 121, the second light emitting element 122, and the third light emitting element 123 are all disposed within the range of the height in the Z direction of the first filter layer 32. In other words, the first light emitting element 121, the second light emitting element 122, and the third light emitting element 123 are disposed at the same position in the Z direction as the first filter layer 32. Note that the magnitude relationship between the height (thickness) in the Z direction of the bandpass filter layer 37 and the organic EL element forming section 62 is not limited to the configuration shown in FIG. 4.

[0048] The organic EL element forming section 62 includes a first light-emitting region 621 that constitutes the first light-emitting element 121, a second light-emitting region 622 that constitutes the second light-emitting element 122, and a third light-emitting region 623 that constitutes the third light-emitting element 123. The first light-emitting region 621, the second light-emitting region 622, and the third light-emitting region 623 are arranged in this order in a direction away from the light-receiving section 11, with the first light-emitting region 621, the second light-emitting region 622, and the third light-emitting region 623 being disposed on the side closest to the light-receiving section 11.

[0049] The first light-emitting region 621, the second light-emitting region 622, and the third light-emitting region 623 each include a first electrode 65 and a second electrode 66 facing each other in the Z direction, and an organic light-emitting layer 67 formed between the first electrode 65 and the second electrode 66. The organic light-emitting layer 67 includes an organic material that emits light when a current is supplied. The first light-emitting region 621 includes, as the organic light-emitting layer 67, a first light-emitting layer 671 including a green light-emitting material. The second light-emitting region 622 includes, as the organic light-emitting layer 67, a second light-emitting layer 672 including a red light-emitting material. The third light-emitting region 623 includes, as the organic light-emitting layer 67, a third light-emitting layer 673 including a near-infrared light-emitting material. The first light-emitting layer 671, the second light-emitting layer 672, and the third light-emitting layer 673 are arranged in the same layer.

[0050] In addition, the first light-emitting region 621, the second light-emitting region 622, and the third light-emitting region 623 may each have a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer in addition to the organic light-emitting layer 67 between the first electrode 65 and the second electrode 66.

[0051] The first light-emitting element 121, the second light-emitting element 122, and the third light-emitting element 123 are top-emission organic EL elements that can extract light from the +Z side of the organic light-emitting layer 67. The first light-emitting element 121, the second light-emitting element 122, and the third light-emitting element 123 each include a reflective layer 64 that is disposed within the wiring layer 61. The reflective layer 64 is formed at a position that overlaps with each of the first light-emitting layer 671, the second light-emitting layer 672, and the third light-emitting layer 673 from the -Z direction (i.e., the semiconductor substrate 20 side).

[0052] The first electrode 65 is an anode. The first electrode 65 is a transparent electrode made of, for example, indium tin oxide (ITO). The first electrode 65 is formed on the surface of the wiring layer 61 in the +Z direction. In this embodiment, the first electrode 65 is separated for each light-emitting element. For example, the first electrode 65 is formed in three locations corresponding to the first light-emitting region 621, the second light-emitting region 622, and the third light-emitting region 623, respectively.

[0053] The second electrode 66 is a cathode. The second electrode 66 is a light-transmitting electrode made of, for example, a silver-magnesium alloy (AgMg). The second electrode 66 faces the organic light-emitting layer 67 from the side opposite to the semiconductor substrate 20 (+Z direction). The second electrodes 66 of the three light-emitting elements are continuous. The first electrodes 65 are arranged in three positions and extend in the direction in which they are aligned.

[0054] In the wiring layer 61, conductive layers 55 and conductive plugs 57 are arranged to form wiring and anode contacts 126, 127, and 128 (see FIG. 3) for respectively connecting the three first electrodes 65 to the drive circuit 13. In addition, in the wiring layer 61, conductive layers 55 and conductive plugs 57 are arranged to form wiring and cathode contact 129 (see FIG. 3) for connecting the second electrode 66 to the GND of the drive circuit 13. The wiring structure in the wiring layer 61 and the drive circuit 13 are configured to drive the first light-emitting element 121, the second light-emitting element 122, and the third light-emitting element 123 in a passive matrix manner.

[0055] The light receiving section 11 and the light emitting section 12 are covered with a cover plate 72 via a transparent resin layer 71. The surface of the cover plate 72 in the +Z direction forms the detection surface 10. The cover plate 72 is optically transparent and may be made of, for example, a glass plate or a quartz plate. The transparent resin layer 71 is made of, for example, a transparent resin such as epoxy resin or acrylic resin.

[0056] <Major Effects of This Embodiment> As described above, the detection device 3 of this embodiment comprises a semiconductor substrate 20, a first photoelectric conversion section 31 formed on the semiconductor substrate 20, a first light-emitting layer 671 formed by stacking on the semiconductor substrate 20, and a first filter layer 32 formed by stacking on the first photoelectric conversion section 31.

[0057] More specifically, the detection device 3 of this embodiment includes a semiconductor substrate 20, a light-emitting section 12 formed on a first surface 21 of the semiconductor substrate 20, and a light-receiving section 11 formed adjacent to the light-emitting section 12 on the first surface 21. The light-receiving section 11 includes a first photoelectric conversion section 31 formed within a layer of the semiconductor substrate 20 and a first filter layer 32 formed on the surface of the first photoelectric conversion section 31. The light-emitting section 12 includes a first light-emitting element 121 disposed at the same position as the first filter layer 32 in the Z direction, which is the normal direction of the semiconductor substrate 20. The first light-emitting element 121 includes a first electrode 65, a light-transmitting second electrode 66 facing the first electrode 65 from the side opposite the semiconductor substrate 20, and a first light-emitting layer 671 formed between the first electrode 65 and the second electrode 66.

[0058] The measurement device 100 of this embodiment includes a detection device 3 and a control device 5 as an information analysis unit that identifies biological information from a detection signal indicating the detection result by the detection device 3.

[0059] In the detection device 3 of this embodiment, the light receiving unit 11 and the light emitting unit 12 are formed on a common semiconductor substrate 20 as a base, so the gap (clearance) between the light receiving unit 11 and the light emitting unit 12 is smaller than in the past. Conventionally, when chipped LEDs or photodiodes are mounted on a substrate, the gap between the light receiving unit 11 and the light emitting unit 12 is measured in millimeters. However, when the light receiving unit 11 and the light emitting unit 12 are formed directly on the semiconductor substrate 20 using a technology for forming a layer structure including semiconductor layers, insulator layers, conductor layers constituting wiring and electrodes, and organic material layers, the gap between the first light emitting element 121 and the first light receiving unit 111 can be measured in microns. This allows the detection device 3 to be miniaturized.

[0060] Furthermore, in the detection device 3 of this embodiment, the light-receiving section 11 has the first photoelectric conversion section 31 formed within a layer of the semiconductor substrate 20, so the height of the detection device 3 in the Z direction is reduced. Furthermore, in the light-emitting section 12, the entire organic EL element forming section 62 that constitutes the first light-emitting element 121 is disposed within the range of the height of the first filter layer 32 in the Z direction. Therefore, the detection device 3 can be made thinner.

[0061] If the gap between the light receiving unit 11 and the light emitting unit 12 can be reduced, the amount of light received that is emitted from the light emitting unit 12 and returns to the light receiving unit 11 from the measurement site M increases. In particular, when the first light LG emitted from the light emitting unit 12 is green light, the green light returns without diffusing to a shallow region inside the subject's body. Therefore, the amount of received light decreases rapidly as the distance from the light-emitting unit 12 increases. Therefore, by reducing the gap between the light-receiving unit 11 and the light-emitting unit 12, the amount of received first light LG (green light) emitted from the light-emitting unit 12 can be increased. As a result, the necessary amount of light can be secured even if the amount of light emitted by the first light-emitting element 121 is reduced, so the power consumption of the light-emitting unit 12 can be reduced. Therefore, power saving of the detection device 3 can be achieved. Furthermore, since a large amount of light returning from the measurement site M can be received, the S / N ratio can be improved. As a result, the measurement device 100 can identify biological information from a detection signal S with a high S / N ratio, thereby improving measurement accuracy.

[0062] Furthermore, the first light-emitting element 121 has a light-transmitting second electrode 66 disposed on the opposite side of the semiconductor substrate 20, and is a top-emission organic EL light-emitting element, so it emits a large amount of light. Therefore, even if the amount of current is reduced and the amount of light emitted is reduced, the necessary amount of light can be secured, so the power consumption of the light-emitting unit 12 can be reduced. This allows the detection device 3 to be made more energy-efficient.

[0063] In this embodiment, the light receiving unit 11 has a second light receiving unit 112 including a second photoelectric conversion unit 33 formed in a layer of the semiconductor substrate 20 and a second filter layer 34 formed on the surface of the second photoelectric conversion unit 33. The second photoelectric conversion unit 33 is located farther from the light emitting unit 12 than the first photoelectric conversion unit 31. The light emitting unit 12 also includes a second light emitting element 122 that emits second light LR (red light) having a longer wavelength than the first light LG (green light) emitted by the first light emitting element 121. The second light emitting element 122 is located farther from the first light receiving unit 111 than the first light emitting element 121.

[0064] Furthermore, the light emitting unit 12 includes a third light emitting element 123 that emits third light LI (near-infrared light) having a longer wavelength than the second light LR. The third light emitting element 123 is further away from the first light receiving unit 111 than the second light emitting element 122.

[0065] With this configuration, the light-emitting unit 12 can emit three types of light: first light LG (green light), second light LR (red light), and third light LI (near-infrared light). The light-receiving unit 11 can receive light using two photoelectric conversion units. Therefore, light in multiple wavelength bands can be received by multiple light-receiving units, and a detection signal S1 representing the received light intensity of the first light LG (green light), a detection signal S2 representing the received light intensity of the second light LR (red light), and a detection signal S3 representing the received light intensity of the third light LI (near-infrared light) can be obtained. Various types of biological information can be determined from the detection signals S1, S2, and S3. For example, the subject's pulse rate can be determined based on the detection signal S1. Furthermore, the subject's oxygen saturation can be determined by analyzing the detection signals S2 and S3.

[0066] In this embodiment, the light-emitting unit 12 has the first light-emitting element 121, which emits the first light LG (green light), arranged closest to the light-receiving unit 11. This arrangement allows the light-receiving unit 11 to receive a large amount of the first light LG (green light) that returns after propagating a short distance within the living body. Therefore, even if the emission intensity of the first light-emitting element 121 is reduced, the first light LG (green light) that has propagated within the living body can be sufficiently detected by the light-receiving unit 11. This makes it possible to increase the S / N ratio of the detection signal S1, which represents the received light intensity of the first light LG (green light), while reducing the power consumption of the light-emitting unit 12.

[0067] In this embodiment, the first filter layer 32 provided in the first light receiving section 111 includes a bandpass filter layer 37 that selectively transmits light of a wavelength (i.e., green light) emitted from the first light emitting element 121 in the light emitting section 12. As described above, the first light receiving section 111 is disposed in a position closest to the light emitting element 12 in the light receiving section 11, and therefore receives a large amount of the first light LG (green light) that returns after propagating a short distance within the living body. Therefore, by disposing the bandpass filter layer 37 in the first light receiving section 111, the second light LR (red light) and third light LI (near-infrared light) emitted from other light emitting elements are cut, and the received light intensity of the first light LG (green light) is displayed. This can improve the S / N ratio of the detection signal S1 that indicates the received light intensity of the first light LG (green light). Furthermore, the bandpass filter layer 37 can cut out external light in a wavelength band different from that of the green light, thereby reducing noise caused by external light. This can improve the S / N ratio of the detection signal S1 that indicates the received light intensity of the first light LG (green light).

[0068] In this embodiment, the first filter layer 32 and the second filter layer 34 include an angle-limiting filter layer 35. The angle-limiting filter layer 35 transmits light incident at angles smaller than the allowable incident angle and blocks light incident at angles larger than the allowable incident angle. Therefore, the first light receiving section 111 and the second light receiving section 112 can each block external light incident from a direction different from the measurement site M of the living body, thereby increasing the S / N ratio of the detection signal S1 obtained from the first light receiving section 111 and increasing the S / N ratios of the detection signals S2 and S3 obtained from the second light receiving section 112.

[0069] Here, the second filter layer 34 does not include a bandpass filter layer. As described above, the first light LG (green light) can propagate only a shorter distance within a living body than the second light LR (red light) or the third light LI (near-infrared light). Therefore, the first light LG (green light) does not reach the position of the second light receiving section 112, and therefore, even without a bandpass filter layer, the first light LG (green light) does not enter the second photoelectric conversion section 33. Therefore, the second light receiving section 112 can omit a bandpass filter layer, thereby reducing costs.

[0070] In this embodiment, the light-emitting unit 12 is shaped to surround the light-receiving unit 11, and in the light-receiving unit 11, the first light-receiving unit 111 is shaped to surround the second light-receiving unit 112. Therefore, in the semiconductor substrate 20, the first photoelectric conversion unit 31 is formed in a shape that surrounds the second photoelectric conversion unit 33. As described above, the first light LG (green light) propagates only a short distance within the living body before being emitted, so it does not reach far, and the amount of light that can be received is small. Therefore, by configuring the light-emitting unit 12 to surround the light-receiving unit 11 all around, the amount of light directed toward the light-receiving unit 11 can be increased. Furthermore, by arranging the first photoelectric conversion unit 31 in a shape that surrounds the second photoelectric conversion unit 33 all around, the entire area close to the light-emitting unit 12 can receive the first light LG (green light). Therefore, the amount of received first light LG (green light) can be increased.

[0071] The light-emitting section 12 of this embodiment does not have an active element such as a switching transistor for each light-emitting element, but has a passive matrix organic EL element structure. Therefore, the structure of the light-emitting section 12 is simple, and the light-emitting section 12 is easy to manufacture.

[0072] In the light-emitting section 12 of this embodiment, the wiring layer 61 is provided with a reflective layer 64 at a position overlapping each of the first light-emitting layer 671, the second light-emitting layer 672, and the third light-emitting layer 673 from the semiconductor substrate 20 side. Therefore, in each light-emitting element, light in a predetermined wavelength range among the light generated in the organic light-emitting layer 67 resonates between the reflective layer 64 and the second electrode 66 (cathode). This makes the peak of the wavelength distribution of the light extracted from each light-emitting element in the +Z direction steeper, thereby increasing the intensity and color purity of the light (first light LG, second light LR, third light LI) emitted from the light-emitting section 12.

[0073] The detection device 3 of this embodiment has a transparent cover plate 72 that covers the light-emitting unit 12 and the light-receiving unit 11 from the side opposite the semiconductor substrate 20, and a transparent resin layer 71 formed between the light-emitting unit 12 and the light-receiving unit 11 and the cover plate 72. This allows the formation of a protective layer that protects the light-receiving unit 11 and the light-emitting unit 12. In addition, the detection surface 10 can be configured by the cover plate 72.

[0074] <Modifications of the detection device> (1) The light-emitting unit 12 in the above embodiment is configured to be able to emit light of three wavelength bands: the first light LG (green light), the second light LR (red light), and the third light LI (near-infrared light). Either the third light emitting element 123 or the second light emitting element 122 may be omitted.

[0075] (2) In the above embodiment, the first electrode 65 is a transparent electrode (ITO film), but the first electrode 65 may be a light-shielding electrode.

[0076] (3) In the above embodiment, the light-emitting unit 12 is configured to drive each light-emitting element using a passive matrix method, but it may also be configured to drive each light-emitting element using an active matrix method. For example, a switching transistor can be formed in a layer of the semiconductor substrate 20 at a position overlapping each light-emitting element in the Z direction.

[0077] (4) The light-emitting unit 12 may be configured so that each light-emitting element includes a color filter. FIG. 5 is a cross-sectional view schematically showing the cross-sectional configuration of the light-receiving unit 11 and the light-emitting unit 12 when each light-emitting element includes a color filter. As shown in FIG. 5, the first light-emitting element 121 includes a first color filter 681 overlapping the first light-emitting layer 671. The second light-emitting element 122 includes a second color filter 682 overlapping the second light-emitting layer 672. The third light-emitting element 123 includes a third color filter 683 overlapping the third light-emitting layer 673. The first color filter 681, the second color filter 682, and the third color filter 683 are formed on the surface of the sealing layer 63 in the +Z direction.

[0078] The first color filter 681 selectively transmits light in a wavelength band corresponding to the first light LG (green light). The second color filter 682 selectively transmits light in a wavelength band corresponding to the second light LR (red light). The third color filter 683 selectively transmits light in a wavelength band corresponding to the third light LI (near-infrared light). By providing the first color filter 681, the second color filter 682, and the third color filter 683, it is possible to improve the color purity of the first light LG (green light), the second light LR (red light), and the third light LI (near-infrared light) emitted from the light-emitting unit 12.

[0079] (5) As shown in Figure 5, when each light-emitting element is configured to have a color filter, the first light-emitting layer 671, the second light-emitting layer 672, and the third light-emitting layer 673 can all be formed from an organic material that emits white light.

[0080] (6) In the above embodiment, both the first light receiving section 111 and the second light receiving section 112 are provided with the angle limiting filter layer 35. However, the angle limiting filter layer 35 may be omitted from one or both of the first light receiving section 111 and the second light receiving section 112. For example, if a structure is adopted that can block external light from the light receiving section 11 and the light emitting section 12, the angle limiting filter layer 35 for reducing noise due to external light can be omitted.

[0081] 6 is a cross-sectional view that schematically shows the cross-sectional configuration of the light receiving section 11 and the light emitting section 12 when the angle limiting filter layer 35 is omitted. In the configuration shown in FIG. 6, the first light receiving section 111 has a first filter layer 32, which is made up of only a bandpass filter layer 37. The second light receiving section 112 does not have a filter layer, and a transparent resin layer 71 is formed on the surface of the second photoelectric conversion section 33. The light emitting section 12 has a wiring layer 61, but the layer structure of the wiring layer 61 is simpler than the configuration shown in FIG. 4.

[0082] (7) In the above embodiment, the second filter layer 34 does not include a bandpass filter layer, but the first filter layer 32 and the second filter layer 34 may each include a bandpass filter layer that transmits light of different wavelength bands. For example, the second filter layer 34 may be provided with a bandpass filter layer that selectively transmits one or both of the second light LR (red light) and the third light LI (near-infrared light).

[0083] (8) In the above embodiment, the first light-emitting element 121, the second light-emitting element 122, and the third light-emitting element 123 are entirely disposed within the range of the thickness (height) in the Z direction of the first filter layer 32. However, a configuration may also be adopted in which part or all of the first light-emitting element 121, the second light-emitting element 122, and the third light-emitting element 123 in the Z direction are disposed outside the range of the thickness (height) in the Z direction of the first filter layer 32. For example, as shown in FIG. 6 , in a case where the angle limiting filter layer 35 is omitted and the thickness (height) in the Z direction of the bandpass filter layer 37 is reduced, part or all of the organic EL element forming portion 62 constituting the first light-emitting element 121, the second light-emitting element 122, and the third light-emitting element 123 can be disposed further in the +Z direction than the first filter layer 32.

[0084] (9) Fig. 7 is a plan view schematically showing the planar shapes of a modified light receiving section 11 and light emitting section 12. As shown in Fig. 7, the light receiving section 11 and light emitting section 12 may have a circular planar shape instead of a rectangular shape. [Explanation of symbols]

[0085] 1...housing, 2...belt, 3...detection device, 4...display device, 5...control device, 6...storage device, 10...detection surface, 11...light receiving section, 12...light emitting section, 13...drive circuit, 14...output circuit, 20...semiconductor substrate, 21...first surface, 31...first photoelectric conversion section, 32...first filter layer, 33...second photoelectric conversion section, 34...second filter layer, 35...angle limiting filter layer, 36...angle limiting filter, 37...band Pass filter layer, 41...n-type semiconductor layer, 42...p-type semiconductor layer, 43...n-type semiconductor layer, 44...light receiving surface, 51...conductive layer, 52...interlayer insulating film, 53...light shielding body, 54...opening, 55...conductive layer, 56...interlayer insulating film, 57...conductive plug, 58...multilayer film, 59...light shielding wall, 61...wiring layer, 62...organic EL element forming portion, 63...sealing layer, 64...reflective layer, 65...first electrode, 66...second electrode, 67...organic EL element Optical layer, 71...transparent resin layer, 72...cover plate, 100...measuring device, 111...first light receiving section, 112...second light receiving section, 113, 115...anode electrode, 114, 116...cathode electrode, 121...first light emitting element, 122...second light emitting element, 123...third light emitting element, 126, 127, 128...anode contact, 129...cathode contact, 351...first region, 352...second region, 621...first light emitting region , 622...second light-emitting region, 623...third light-emitting region, 671...first light-emitting layer, 672...second light-emitting layer, 673...third light-emitting layer, 681...first color filter, 682...second color filter, 683...third color filter, C1, C2, C3, C4...terminals, D1, D2, D3, D4...terminals, LG...first light, LR...second light, LI...third light, M...measurement site, S, S1, S2, S3...detection signal.

Claims

1. a semiconductor substrate; a first photoelectric conversion unit formed on the semiconductor substrate; a first light emitting layer formed by laminating on the semiconductor substrate; a first filter layer formed by being laminated on the first photoelectric conversion portion; a light emitting portion formed on a first surface of the semiconductor substrate and configured to emit light toward a living body; a light receiving unit formed on the first surface at a position adjacent to the light emitting unit and configured to receive light from a living body; the light receiving unit includes the first photoelectric conversion unit formed in a layer of the semiconductor substrate, and the first filter layer formed on a surface of the first photoelectric conversion unit, the light emitting section includes a first light emitting element at least part of which is disposed at the same position as the first filter layer in a normal direction of the semiconductor substrate, The detection device is characterized in that the first light-emitting element comprises a first electrode, a light-transmitting second electrode facing the first electrode from the side opposite the semiconductor substrate, and the first light-emitting layer formed between the first electrode and the second electrode.

2. The detection device according to claim 1 , wherein the first electrode has a light-shielding property.

3. 3. The detection device according to claim 1, further comprising a reflective layer overlapping the first light-emitting layer from the semiconductor substrate side.

4. 4. The detection device according to claim 1, wherein the first filter layer includes a bandpass filter layer that selectively transmits light of a wavelength emitted from the light-emitting portion.

5. the light-emitting unit includes a second light-emitting element that emits second light having a wavelength longer than that of the first light emitted by the first light-emitting element, The detection device according to claim 4 , wherein the second light-emitting element is located farther from the light-receiving unit than the first light-emitting element.

6. the first light is light in a green wavelength band, the bandpass filter layer selectively transmits the first light; 6. The detection device according to claim 5, wherein the second light is light in a red wavelength band or a near-infrared wavelength band.

7. the second light-emitting element includes a second light-emitting layer; the first light-emitting element includes a first color filter overlapping the first light-emitting layer; 7. The detection device according to claim 5, wherein the second light-emitting element includes a second color filter overlapping the second light-emitting layer.

8. The light receiving unit a second photoelectric conversion unit formed in a layer of the semiconductor substrate, and a second filter layer formed on a surface of the second photoelectric conversion unit; The detection device according to claim 5 , wherein the second photoelectric conversion unit is located farther from the light emitting unit than the first photoelectric conversion unit.

9. 9. The detection device of claim 8, wherein the first filter layer and the second filter layer each comprise an angle-limiting filter layer.

10. the light-emitting portion has a shape surrounding the light-receiving portion, 10. The detection device according to claim 8, wherein the first photoelectric conversion unit has a shape that surrounds the second photoelectric conversion unit.

11. a transparent cover plate that covers the light-emitting portion and the light-receiving portion from the side opposite to the semiconductor substrate; 11. The detection device according to claim 1, further comprising a transparent resin layer formed between the light-emitting section and the cover plate, and between the light-receiving section and the cover plate.

12. A detection device according to any one of claims 1 to 11; and an information analysis unit that identifies biological information from a detection signal that indicates a detection result by the detection device.

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