Distance measuring device

Abstract

A ranging device includes: a first component including a first optical waveguide configured to transmit a chirp signal; a light source generating light for being modulated by a modulator to generate the chirp signal; and a second component including logic circuitry to control the light source. The first component and the second component are stacked. The ranging device also includes a first conductor forming at least a portion of an electrical connection between the logic circuit and the light source, and the first conductor penetrates the first component at a position spaced apart from the light source in a first direction.

Description

Cross - reference to related applications

[0001] This application claims the benefit of priority of Japanese Patent Application JP 2022 - 192058, filed on November 30, 2022, the entire content of which is incorporated herein by reference. Technical field

[0002] The present invention relates to a distance - measuring device. Background art

[0003] An optical detection and ranging (LiDAR) system using a photon - integrated circuit (PIC) has been developed, in which optical elements such as silicon (Si) waveguides are stacked on a silicon - on - insulator (SOI) substrate instead of optical fibers (for example, see Patent Document 1). List of cited documents Patent documents

[0004] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019 - 121691 Summary of the invention Technical problem

[0005] In such a system, for example, due to heat generation in a laser serving as a light source, the operation becomes unstable. Therefore, it is desirable to provide a distance - measuring device capable of suppressing operation instability caused by heat generation or the like. Solution to the technical problem

[0006] According to at least one embodiment, a ranging device includes: a first component including a first optical waveguide configured to transmit a chirp signal; a light source that generates light to be modulated by a modulator to generate the chirp signal; and a second component including logic circuitry that controls the light source. The first component and the second component are stacked. The ranging device further includes a first conductor that forms at least a part of an electrical connection between the logic circuitry and the light source, and the first conductor penetrates the first component at a position spaced apart from the light source in a first direction. The first conductor passes through the first component. The first conductor passes through at least a part of the second component. The second component includes a silicon layer and an interlayer insulating film. The first conductor passes through the interlayer insulating film to reach the silicon layer. The first conductor is electrically connected to a wiring of the interlayer insulating film. The wiring is located at a joint surface between the first component and the second component. The wiring is located between a first surface of the interlayer insulating film and a second surface of the interlayer insulating film opposite to the first surface. The ranging device further includes at least one second conductor that electrically connects the first conductor to the light source. The first component includes at least a part of the at least one second conductor. At least a part of the at least one second conductor extends in the first direction. The at least one second conductor includes a conductive bump. The ranging device further includes: a third component including the light source, and the first component is located between the second component and the third component. The third component includes at least a part of the at least one second conductor. The first conductor passes through the third component, the first component, and at least a part of the second component.

[0007] According to at least one embodiment, a ranging device includes: a first component including a first silicon layer including a first optical waveguide configured to transmit an optical signal; a light source that generates light to be modulated by a modulator to generate the optical signal; a second component including a second silicon layer including logic circuitry that controls the light source. The first component and the second component are stacked. The ranging device further includes a first conductor that forms at least a part of an electrical connection between the logic circuitry and the light source. The first conductor penetrates the first component at a position spaced apart from the light source in a first direction. The light source is located between the first optical waveguide and the first conductor. The first component further includes: a beam splitter configured to separate the optical signal into a transmission signal and a reference signal; and a coupler and a detector circuit configured to output a beat signal based on the reference signal and a reflected signal. The logic circuitry includes: a controller configured to output an electronic control signal that controls generation of the optical signal.

[0008] According to at least one embodiment, a ranging device includes: a first component including a first optical waveguide configured to transmit a chirp signal; a light source that generates light to be modulated by a modulator to generate a chirp signal; a second component including a logic circuit that controls the light source. The first component and the second component are stacked. The ranging device includes: a first conductor that forms at least a part of an electrical connection between the logic circuit and the light source, wherein the first conductor penetrates the first component at a position spaced apart from the light source in a first direction. The ranging device further includes at least one second conductor that forms the remaining part of the electrical connection between the logic circuit and the light source, wherein at least a part of the at least one second conductor extends in the first direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 Figure 1 is a diagram showing an exemplary schematic configuration of a ranging device according to a first embodiment of the present invention. Figure 2 Figure 2 is a diagram showing an exemplary planar configuration of Figure 1 the ranging device. Figure 3 Figure 3 is a diagram showing an exemplary cross-sectional configuration taken along line A-A in Figure 2 . Figure 4 Figure 4 is a diagram showing an exemplary cross-sectional configuration taken along line B-B in Figure 2 . Figure 5 Figure 5 is a diagram showing an exemplary cross-sectional configuration taken along line C-C in Figure 2 . Figure 6 Figure 6 is a diagram showing an exemplary schematic configuration of the antenna in Figure 1 . Figure 7 Figure 7 is a diagram showing an exemplary cross-sectional configuration taken along line A-A in Figure 6 . Figure 8 Figure 8 is a diagram showing an exemplary cross-sectional configuration taken along line B-B in Figure 6 . Fig. 9 Fig. 9 is a diagram showing an exemplary schematic configuration of the detector in Figure 1 . ​​​​​​​​​​​​​​​​​​​ Fig.10 Fig.10 is a diagram showing an exemplary three-dimensional structure of a detector in Fig. 9 . Fig.11 Fig.11 is a cross-sectional view for explaining the manufacturing method of a distance measuring device for Figure 1 . Fig.12 Fig.12 is a cross-sectional view for explaining the manufacturing method after Fig.11 . Fig.13 Fig.13 is a cross-sectional view for explaining the manufacturing method after Fig.12 . Fig.14 Fig.14 is a cross-sectional view for explaining the manufacturing method after Fig.13 . Fig.15 Fig.15 is a cross-sectional view for explaining the manufacturing method after Fig.14 . Fig.16 Fig.16 is a cross-sectional view for explaining the manufacturing method after Fig.15 . Fig.17 Fig.17 is a cross-sectional view for explaining the manufacturing method after Fig.16 . Fig.18 Fig.18 is a cross-sectional view for explaining the manufacturing method after Fig.16 . Fig.19 Fig.19 is a cross-sectional view for explaining the manufacturing method after Fig.17 . Fig. 20 Fig. 20 is a cross-sectional view for explaining the manufacturing method after Fig.18 . Fig.21 Fig.21 is a diagram showing a modified example of the cross-sectional structure of Figure 5 . Fig. 22 Fig. 22 is a diagram showing a modified example of the cross-sectional structure of Figure 4 . Fig.23 Fig.23 is a diagram showing a modified example of the planar structure of Figure 2 .​​​​​​​​​​​​​​​​​​​​​​​​​​​ Fig.24 Fig.24 is a diagram showing an exemplary cross-sectional structure taken along line A-A in Fig.23 . Fig.25 Fig.25 is a diagram showing an exemplary schematic structure of a distance measuring device according to a second embodiment of the present invention. Fig.26 Fig.26 is a diagram showing an exemplary planar structure of the distance measuring device of Fig.25 . Fig. 27 Fig. 27 is a diagram showing an exemplary cross-sectional structure taken along line A-A in Fig.26 . Fig.28 Fig.28 is a diagram showing an exemplary cross-sectional structure taken along line B-B in Fig.26 . Fig.29 Fig.29 is a diagram showing an exemplary cross-sectional structure taken along line C-C in Fig.26 . Fig.30 Fig.30 is a diagram showing a modified example of the cross-sectional structure of Fig.29 . Fig.31 Fig.31 is a diagram showing a modified example of the cross-sectional structure of Fig.28 . Fig.32 Fig.32 is a diagram showing a modified example of the cross-sectional structure of Fig.28 . Fig.33 Fig.33 is a diagram showing an exemplary layout of the groove section in Fig.32 . Fig.34 Fig.34 is a diagram showing an exemplary layout of the groove section in Fig.32 . Fig.35 Fig.35 is a diagram showing an exemplary layout of the groove section in Fig.32 . Fig.36 Fig.36 is a diagram showing a modified example of the cross-sectional structure of Fig.31 . ​​​​​​​​​​​​​​​​​​​​​​​​​​​ Fig.37 Fig.37 is a figure showing a modified example of the cross-sectional structure of Fig.32 . Fig.38 Fig.38 is a figure showing a modified example of the cross-sectional structure of Fig.28 . Fig.39 Fig.39 is a figure showing a modified example of the cross-sectional structure of Fig.29 . Fig.40 Fig.40 is a figure showing a modified example of the cross-sectional structure of Fig.28 . Fig.41 Fig.41 is a figure showing a modified example of the cross-sectional structure of Fig.29 . Fig.42 Fig.42 is a figure showing an example of providing a groove portion in a recessed section in Figures 38 to 41 . Fig.43 Fig.43 is a figure showing an example of providing a groove portion in a recessed section in Figures 38 to 41 . Fig.44 Fig.44 is a figure showing an example of providing a groove portion in a recessed section in Figures 38 to 41 . Fig.45 Fig.45 is a figure showing a modified example of the cross-sectional structure of Fig.28 . Fig.46 Fig.46 is a figure showing a modified example of the cross-sectional structure of Fig.29 . Fig.47 Fig.47 is a figure showing a modified example of the cross-sectional structure of Fig.46 . Fig.48 Fig.48 is a figure showing a modified example of the planar structure of a recessed section in Fig.26 . Fig.49 Fig.49 is a figure showing a modified example of the cross-sectional structure of a recessed section in Fig.28 . Fig.50 Fig.50 is a figure showing Fig.26 ​​​​​​​​​​​​​​​​​​​​​​​​​​​Diagrams of the concave portion in [ ] and modified examples of the planar structure of the laser chip. Fig.51 Fig.51 is a diagram showing Fig.28 a modified example of the cross-sectional structure of the concave portion in [ ]. Fig.52 Fig.52 is a diagram showing Fig.26 a modified example of the planar structure of the concave portion in [ ]. Fig.53 Fig.53 is a diagram showing an exemplary cross-sectional structure taken along line A-A in [ ]. Fig.52 Fig.54 Fig.54 is a diagram showing Fig.53 the exemplary planar structure of the concave portion and the laser chip in [ ] and Fig.53 the exemplary structure of the bottom surface of the laser chip in [ ]. Fig.55 Fig.55 is a diagram showing Fig.28 a modified example of the cross-sectional structure of the concave portion in [ ]. Fig.56 Fig.56 is a diagram showing Fig.28 a modified example of the cross-sectional structure of the first die in [ ]. Fig.57 Fig.57 is a diagram showing Fig.28 a modified example of the cross-sectional structure of the first die in [ ]. Fig.58 Fig.58 is a diagram showing Fig.28 a modified example of the cross-sectional structure of the first die in [ ]. Fig.59 Fig.59 is a block diagram showing an example of the schematic structure of a vehicle control system. Fig.60 Fig.60 is a diagram assisting in explaining an example of the installation positions of the out-of-vehicle information detection unit and the imaging unit. Detailed Description of the Embodiments

[0010] Hereinafter, some embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the description will be carried out in the following order. 1. First Embodiment ( Figures 1 to 20 ) An example of stacking a laser substrate, a PIC substrate, and a signal processing substrate through through-chip via (TCV) connections​​​​​​​​​​​​​​​​​​​​​ 2. Variations of the First Embodiment Variation 2-1: Example of connecting the anode and cathode of a laser diode to the metal wiring of a signal processing substrate ( Fig.21 ) Variation 2-2: Example of providing a heat dissipation structure directly below the laser diode ( Fig. 22 ) Variation 2-3: Example of providing a heat dissipation structure directly above the laser diode ( Fig.23 and Fig.24 ) 3. Second Embodiment ( Figure 25 to Figure 29 ) Example of mounting a laser chip on a PIC substrate 4. Variations of the Second Embodiment Variation 4-1: Example of connecting the anode and cathode of a laser chip to the metal wiring of a signal processing substrate ( Fig.30 ) Variation 4-2: Example of providing a groove portion on the bottom surface of a recess in a PIC substrate ( Figure 31 to Figure 37 ) Variation 4-3: Example of providing a via in a recess of a PIC substrate ( Fig.38 and Fig.39 ) Variation 4-4: Example of stacking a PIC substrate and a signal processing substrate by Cu-Cu bonding ( Figures 40 to 44 ) Variation 4-5: Example of connecting a signal processing substrate and a PIC substrate to each other by wire bonding ( Figure 45 to Figure 47 ) Variation 4-6: Example of providing a measure to prevent return light on the light incident surface of a recess in a PIC substrate or the light emitting end face of a laser chip ( Figures 48 to 50 ) Variation 4-7: Example of providing an alignment structure on the bottom surface of a recess in a PIC substrate ( Figures 51 to 54 ) Variation 4-8: Example of providing a laser chip height adjustment member on the bottom surface of a recess in a PIC substrate ( Fig.55 ) Variation 4-9: Example of providing a dedicated waveguide for capturing laser light on a PIC substrate ( Fig.56 ) Variation 4-10: Example of providing a cutout portion on a PIC substrate ( Fig.57 and Fig.58 ) 5. Application Examples ( Fig.59 and Fig.60 ) <1. First Embodiment> Structure

[0011] Figure 1 Shows an exemplary schematic structure of the ranging device 1000 according to the first embodiment of the present invention. Figure 2 Shows an exemplary planar structure of the ranging device 1000. Figure 3 Shows along Figure 2 An exemplary cross-sectional structure taken along line A-A in Figure 4 Shows along Figure 2 An exemplary cross-sectional structure taken along line B-B in Figure 5 Shows along Figure 2 An exemplary cross-sectional structure taken along line C-C in

[0012] The ranging device 1000 includes a frequency-modulated continuous-wave (FMCW) LiDAR. In the FMCW LiDAR, a laser (transmission signal) whose frequency has been modulated to linearly increase over time is continuously applied to determine the distance by the frequency difference between the transmission signal and the reflected light (return signal).

[0013] As Figure 1 Shown, the ranging device 1000 includes, for example, a first bare chip 100, a second bare chip 200, and a third bare chip 300. The first bare chip 100 and the second bare chip 200 are stacked on the third bare chip 300 and are connected to each other through a bonding surface S1 between the first bare chip 100 and the third bare chip 300 and a bonding surface S2 between the second bare chip 200 and the third bare chip 300. The top surface of the second bare chip 200 serves as the incident / emission surface S3. The first, second, and third bare chips 100, 200, 300 may form all or part of the corresponding components herein (for example, each bare chip corresponds to one of the first, second, or third components herein). The bonding surfaces S1 and S2 may also be referred to as joint surfaces. (Second bare chip 200)

[0014] As Figure 1 Shown, the second bare chip 200 includes, for example, a laser 210. In the second bare chip 200, the laser 210 is disposed in the semiconductor substrate 201.

[0015] The laser 210 is a light source that outputs an optical signal. In some examples, the light source generates light for modulation by the modulator 110 to generate a chirp signal transmitted or carried by the waveguide WG1. The laser 210 is a vertical cavity surface emitting laser (VCSEL) and emits a laser beam L (optical signal) having a predetermined fixed wavelength (e.g., 1550 nm) under the control of a controller 310, which will be described later. The surface emitting laser includes, for example, an active layer and a pair of distributed Bragg (Btagg) reflector (DBR) layers. The active layer is sandwiched between a pair of DBR layers in the thickness direction. As Figure 3 shown, the surface emitting laser includes, for example, a contact layer 211 and a contact layer 212. The contact layer 211 is ohmically connected to one of the DBR layers, and the contact layer 212 is ohmically connected to the other DBR layer. The surface emitting laser emits the laser beam L to the first bare chip 100 (Si layer 101, which will be described later) through the contact layer 212 and the bonding surface S2.

[0016] The second bare chip 200 includes wirings that electrically connect the laser 210 and the third bare chip 300 (signal processing circuit) to each other. As Figures 2 to 5 shown, as the above wirings, the second bare chip 200 includes, for example, a wiring 410 that contacts the contact layer 211 and a wiring 420 that contacts the contact layer 212. The wirings 410 and 420 correspond to specific examples of the "first wiring" according to the embodiments of the present invention. In the wirings 410 and 420, one wiring serves as the wiring for the cathode of the laser 210, and the other wiring serves as the wiring for the anode of the laser 210. Hereinafter, the wiring 410 serves as the wiring for the cathode of the laser 210, and the wiring 420 serves as the wiring for the anode of the laser 210. It should be noted that, depending on the structure of the laser 210, the wiring 410 may serve as the wiring for the anode of the laser 210, and the wiring 420 may serve as the wiring for the cathode of the laser 210.

[0017] As Figures 2 to 4 shown, the wiring 410 includes, for example, vias 411, 412, and a wiring layer 413. As Figure 2 , Figure 3 and Figure 5As shown, the wiring 420 includes, for example, vias 421, 422, and a wiring layer 423. The wirings 410 and 420 contain, for example, copper (Cu). The second bare chip 200 (laser 210) is electrically connected to the third bare chip 300 (signal processing circuit) through the wirings 410 and 420. The via 412 and similarly positioned vias or electrical connections described with reference to other figures herein may be referred to as conductors that form at least a part of the electrical connection between the logic circuit and the light source (e.g., between the laser 210 and the logic circuit in the third bare chip 300 that controls the laser 210). Such conductors penetrate at least one component (e.g., more than one of the bare chips 100, 200, and / or 300) at least partially. For example, the conductor (such as the via 412, etc.) penetrates the component (e.g., the bare chip 100) including the waveguide WG1 (e.g., the bare chip 100) at a position spaced apart from the laser 210 in a first direction that is the horizontal direction in this and other figures. In all the figures, the wiring that connects the conductor to the laser 210 may be referred to as at least one conductor that forms the remaining part of the electrical connection between the logic circuit that controls the laser 210 and the laser 210. In Figure 4 and other figures, these conductors or wirings include wirings 411 and 413. Even if not explicitly stated below, it should be understood that at least Figure 4 , Figure 5 , Figures 19 to 22 , Fig.24 , Figure 28 to Figure 32 , Figure 36 to Figure 41 , Fig.46 and Fig.47 show other examples of the above conductors spaced apart from the laser 210 and / or the above conductors that form the remaining part of the electrical connection between the light source (such as the laser 210, etc.) and the logic circuit that controls the light source (such as the controller 310, etc.). Such conductors may have the heat dissipation characteristics / functions described herein.

[0018] The via 411 is in contact with the contact layer 211 and the wiring layer 413. The via 411 is provided in the semiconductor substrate 201 and extends along the stacking direction of the semiconductor substrate 201. For example, the via 411 includes a metal (e.g., Cu) embedded in a via hole provided in the semiconductor substrate 201. The via 412 is in contact with the wiring layer 413 and a wiring layer (e.g., Cu) in the interlayer insulating film 302 to be described later. This wiring layer is electrically connected to the controller 310, for example. The via 412 is provided in the first bare chip 100, the second bare chip 200, and the third bare chip 300 and extends from the semiconductor substrate 201 to the interlayer insulating film 302. For example, the via 412 includes a metal (e.g., Cu) embedded in a via hole provided from the semiconductor substrate 201 to the interlayer insulating film 302. The wiring layer 413 is provided on the front surface of the semiconductor substrate 201 and is in contact with the via 411 and the via 412. The wiring layer 413 includes a metal (e.g., Cu).

[0019] The via 421 is in contact with the contact layer 212 and the wiring layer 423. The via 421 is provided in the semiconductor substrate 201 and extends along the stacking direction of the semiconductor substrate 201. For example, the via 421 includes a metal (e.g., Cu) embedded in a via hole provided in the semiconductor substrate 201. The via 422 is in contact with the wiring layer 423 and the Si substrate 301. The via 422 is provided in the first bare chip 100, the second bare chip 200, and the third bare chip 300 and extends from the semiconductor substrate 201 to the interlayer insulating film 302. For example, the via 422 includes a metal (e.g., Cu) embedded in a via hole provided from the semiconductor substrate 201 to the interlayer insulating film 302. The wiring layer 423 is provided on the front surface of the semiconductor substrate 201 and is in contact with the via 421 and the via 422. The wiring layer 423 includes a metal (e.g., Cu).

[0020] The second bare chip 200 and the first bare chip 100 further include, for example, a wiring 430 that electrically connects the detector 160, which will be described later, and the third bare chip 300 (signal processing circuit) to each other. As Figure 2 and Figure 4 shown, for example, the wiring 430 includes a via 431, a via 432, and a wiring layer 433. For example, the wiring 430 includes Cu. The first bare chip 100 (detector 160) is electrically connected to the third bare chip 300 (signal processing circuit) through the wiring 430.

[0021] The via 431 contacts a wiring layer (e.g., Cu) in the interlayer insulating film 302 and the wiring layer 433. For example, this wiring layer is electrically connected to the controller 310. The via 431 extends from the semiconductor substrate 201 to the interlayer insulating film 302. For example, the via 431 contains a metal (e.g., Cu) embedded in a via opening provided from the semiconductor substrate 201 to the interlayer insulating film 302. The via 432 contacts a wiring layer (e.g., Cu) in the interlayer insulating film 102 and the wiring layer 433 that is electrically connected to the detector 160. The via 432 extends from the semiconductor substrate 201 to the interlayer insulating film 102. For example, the via 432 contains a metal (e.g., Cu) embedded in a via opening provided from the semiconductor substrate 201 to the interlayer insulating film 102. The wiring layer 433 is disposed on the front surface of the semiconductor substrate 201 and contacts the via 431 and the via 432. The wiring layer 433 includes a metal (e.g., Cu). (First bare chip 100)

[0022] As Figure 1 shown, for example, the first bare chip 100 includes a modulator 110, a splitter 120, a circulator 130, an antenna 140, a coupler 150, and a detector 160. In the first bare chip 100, the modulator 110, the splitter 120, the circulator 130, the antenna 140, the coupler 150, and the detector 160 are disposed in the PIC substrate 100A.

[0023] As Figures 3 to 5 shown, for example, the PIC substrate 100A includes an Si layer 101, an interlayer insulating film 102, and a buried oxide (BOX) layer 103. The Si layer 101 is sandwiched between the interlayer insulating film 102 and the BOX layer 103. The PIC substrate 100A is obtained by removing the Si substrate 104, which will be described later, from the SOI substrate 106, which will be described later. The BOX layer 103 includes an SiO2 layer. The interlayer insulating film 102 is a layer disposed on the SOI substrate 106 and has a structure in which a plurality of patterned wiring layers are provided in a stacked plurality of SiO2 layers and vias for connecting the wiring layers to each other. The front surface of the interlayer insulating film 102 serves as the bottom surface of the first bare chip 100. The front surface of the interlayer insulating film 102 contacts the top surface of the third bare chip 300 (interlayer insulating film 302). The front surface of the BOX layer 103 serves as the top surface of the first bare chip 100.

[0024] Optical waveguides WG1, WG2, and WG3 are provided in the Si layer 101. The optical waveguide WG1 extends, for example, from a portion directly below the laser 210 through the modulator 110, the optical splitter 120, and the circulator 130 to the antenna 140. The optical waveguide WG2 is an optical wavelength branched from the optical waveguide WG1 in the optical splitter 120 and is coupled to one input terminal (the optical waveguide 151 to be described later) of the coupler 150. The optical waveguide WG3 is an optical waveguide branched from the optical waveguide WG1 in the circulator 130 and is coupled to the other input terminal (the optical waveguide 152 to be described later) of the coupler 150.

[0025] The laser beam L emitted from the laser 210 enters the optical waveguide WG1. The diffraction grating 105 is provided at a position of the optical waveguide WG1 opposite to the laser 210 (a portion directly below the laser 210). For example, the diffraction grating 105 is an element in which a plurality of grooves or through holes are arranged in a row at intervals of several hundred nm in the Si layer 101. The diffraction grating 105 guides the laser beam L emitted from the laser 210 into the optical waveguide WG1. The laser beam L propagating through the optical waveguide WG1 is input to the modulator 110. In other words, the diffraction grating 105 guides the laser beam L emitted from the laser 210 to the modulator 110.

[0026] The modulator 110 performs frequency modulation of the laser beam L under the control of the controller 310. For example, the modulator 110 modulates the laser beam L to linearly increase the frequency of the laser beam L over time and then modulates the laser beam L to linearly decrease the frequency of the laser beam L over time. For example, the modulator 110 periodically repeats such linear increase and decrease of the frequency to generate the transmission signal Stx and outputs the transmission signal Stx to the optical splitter 120 through the optical waveguide WG1. The transmission signal Stx is a chirp signal obtained by frequency modulating the laser beam L by the modulator 110. The optical waveguide WG1 transmits the chirp signal. For example, the modulator 110 is provided in the Si layer 101. The modulator 110 includes, for example, a Mach-Zehnder interferometer in which the Si waveguide is branched into two. In this case, the modulator 110 generates a signal with a changed optical phase by forming a PN junction in one of the branched waveguides and applying an AC waveform voltage to the PN junction to change the refractive index by the carrier plasma effect. The modulator 110 can modulate the phase of the original signal by multiplexing the generated signal waveform and the original waveform at the interferometer output.

[0027] The optical splitter 120 separates the transmission signal Stx into a transmission signal Stx (transmission signal Stx1) for application to the target TG and a transmission signal Stx (transmission signal Stx2) for interfering with the return signal Srx (also referred to as the reflection signal) in the interference coupler 150. The transmission signal Stx1 has most of the energy of the transmission signal Stx. The transmission signal Stx2 is a reference signal whose energy is much smaller than that of the transmission signal Stx1 but is sufficient to interfere with the return signal Srx in the interference coupler 150. The return signal Srx corresponds to a signal having a delayed phase with respect to the transmission signal Stx1. The return signal Srx is generated by the target TG reflecting the transmission signal Stx.

[0028] The optical splitter 120 is an element having three ports. In the optical splitter 120, the first port and the third port are present in the optical waveguide WG1. The second port is present in the optical waveguide WG2. The optical waveguide WG2 is provided near a portion between the first port and the third port of the optical waveguide WG1. This causes the optical signal propagating through the optical waveguide WG1 to leak into the optical waveguide WG2. The optical signal leaking from the optical waveguide WG1 into the optical waveguide WG2 propagates through the optical waveguide WG2 as the transmission signal Stx2. The optical waveguide WG2 transmits the transmission signal Stx2.

[0029] The circulator 130 is an element having three ports. In the circulator 130, the transmission signal Stx1 incident from the first port is transmitted to the third port, and the return signal Srx incident from the third port is transmitted to the second port. In the circulator 130, the first port is coupled to the optical waveguide WG1, and the second port is coupled to the optical waveguide WG2. The third port is coupled to the optical waveguide extending from the antenna 140. For example, the circulator 130 is used to rectify the optical signal to be transmitted and the optical signal received from the Si antenna 141. In the circulator 130, by means of the structure of the optical waveguide including the Si branch, the signal intensity of each of the transmission signal and the reception signal is divided into 50% and 50% at each branch. Processing such half signals enables the transmitted light and the received light to be separated.

[0030] The antenna 140 is a non-mechanical scanner without a driving part. The antenna 140 transmits the transmission signal Stx1 to the target TG through the lens 220 and receives the return signal Srx through the lens 220. The lens 220 is bonded to the region (incident / output surface S3) of the front surface of the second bare chip 200 opposite to the Si antenna 141. The transmission signal Stx1 is output from the incident / output surface S3, and the return signal Srx enters the incident / output surface S3. The lens 220 is bonded to the incident / output surface S3, and the transmission signal Stx is output from the antenna 140 to the outside through the lens 220 and the incident / output surface S3, and the return signal Srx enters the antenna 140 from the outside through the lens 220 and the incident / output surface S3.

[0031] As shown Figure 6 in, for example, FIG. 140, the antenna 140 includes a plurality (e.g., four) of antenna bodies, each of which includes a Si antenna 141 and a pair of heaters 142 disposed on both sides of the Si antenna 141. The antenna bodies all extend in a common direction, and the plurality of antenna bodies are arranged side by side at a predetermined interval in a direction orthogonal to the direction in which the antenna bodies extend.

[0032] The Si antenna 141 includes a diffraction grating provided in the Si layer 101. For example, the diffraction grating is an element in which a plurality of grooves or through holes are arranged side by side in a row in the Si layer 101 at a pitch of several hundred nm. The Si antenna 141 outputs a transmission signal Stx1 having a peak at a specific position corresponding to the pitch of the diffraction grating to the front surface of the Si layer 101 at a predetermined angle under the control of the controller 310. Each of the heaters 142 includes a resistor element extending along the Si antenna 141. The heater 142 heats the Si antenna 141 by the heat generated in the resistor element due to the application of current to the resistor element under the control of the controller 310. In the Si antenna 141, the refractive index is changed by the heating of the heater 142, and the transmission signal Stx1 is output at an angle corresponding to the change in the refractive index. In other words, the Si antenna 141 scans the transmission signal Stx1 in a predetermined external area under the control of the controller 310.

[0033] In the case where the antenna 140 includes four antenna bodies, as shown Figure 6 in, for example, FIG. 140, the antenna 140 further includes: four optical switches 143, with one optical switch 143 provided for each antenna body; and two optical switches 144, with one optical switch 144 provided for every two optical switches 143. Each of the optical switches 143 is a switch for connecting and disconnecting an optical waveguide between two terminals (a first terminal and a second terminal). Each of the optical switches 144 is a switch for connecting and disconnecting an optical waveguide between two terminals (a third terminal and a fourth terminal). As shown Figure 6 in, for example, FIG. 140, the antenna 140 further includes an optical switch 145 coupled to the two optical switches 144. The optical switch 145 is a switch for connecting and disconnecting an optical waveguide between two terminals (a fifth terminal and a sixth terminal).

[0034] In each of the optical switches 143, the first terminal is connected to the antenna body, and the second terminal is connected to the second terminal of another optical switch 143 and the third terminal of the optical switch 144. In each of the optical switches 144, the third terminal is connected to the second terminals of two corresponding optical switches 143, and the fourth terminal is connected to the fourth terminal of another optical switch 144 and the fifth terminal of the optical switch 145. In the optical switch 145, the fifth terminal is connected to the fourth terminals of the two optical switches 144, and the sixth terminal is connected to the second port of the circulator 130.

[0035] As Figure 7 and Figure 8 shown, for example, the antenna body includes a diffraction grating disposed in the Si layer 101, respectively. Figure 7 Shows along Figure 6 An exemplary cross-sectional configuration of the antenna body taken along line A-A in. Figure 8 Shows along Figure 6 An exemplary cross-sectional configuration of the antenna body taken along line B-B in. As Figure 7 and Figure 8 shown, for example, the diffraction grating is an element in which a plurality of grooves are arranged side by side in a row at a pitch of several hundred nm in the Si layer 101. The depth of each groove is, for example, several hundred nm, and the thickness of the portion of the Si layer 101 corresponding to the base of the diffraction grating is, for example, several hundred nm.

[0036] In the Si antenna 141, the transmission signal Stx1 having a peak at a specific position corresponding to the pitch of the diffraction grating is output to the front surface of the Si layer 101 at a predetermined angle. The heater 142 includes a resistor element extending along the Si antenna 141, respectively. The heater 142 heats the Si antenna 141 by the heat generated in the resistor element by applying current to the resistor element under the control of the controller 310. In the Si antenna 141, the refractive index is changed by the heating of the heater 142, and the transmission signal Stx1 is output at an angle corresponding to the change in the refractive index.

[0037] The antenna 140 turns on and off four optical switches 143, two optical switches 144, and one optical switch 145 under the control of the controller 310. Therefore, the antenna 140 outputs the transmission signal Stx1 from each antenna body in a predetermined direction and receives the return signal Srx input from the outside.

[0038] The coupler 150 is an element that generates a beat signal Sbt by the interference between the transmission signal Stx2 and the return signal Srx. The frequency of the beat signal Sbt changes according to the frequency difference between the transmission signal Stx2 and the return signal Srx. The frequency difference changes according to the distance from the Si antenna 141 to the target TG. Therefore, the distance from the Si antenna 142 to the target TG can be estimated based on the frequency of the beat signal Sbt.

[0039] As Fig. 9As shown, for example, the coupler 150 includes an optical waveguide 151 for propagating the transmission signal Stx2 and an optical waveguide 152 for propagating the return signal Srx. Each of the optical waveguides 151 and 152 is, for example, a rib waveguide. A part of the optical waveguide 151 and a part of the optical waveguide 152 are arranged close to each other. This causes the transmission signal Stx2 propagating through the optical waveguide 151 and the return signal Srx propagating through the optical waveguide 152 to interfere with each other, thereby generating a beat signal Sbt.

[0040] The detector 160 is an element that extracts the beat signal Sbt from the signals propagating through the optical waveguides 151 and 152 under the control of the controller 310. The module including the coupler 150 and the detector 160 corresponds to a specific example of the "signal generator for generating a beat signal" according to an embodiment of the present invention. As Fig.10 shown, for example, the detector 160 includes Ge-PDs 161 and 162 connected in series with each other, and a transimpedance amplifier 163 connected to a connection node between the Ge-PD 161 and the Ge-PD 162.

[0041] As Fig. 9 shown, for example, the Ge-PD 161 is a PIN photodiode coupled to the optical waveguide 151. As Fig. 9 shown, for example, the Ge-PD 162 is a PIN photodiode coupled to the optical waveguide 152. The Ge-PDs 161 and 162 each include, for example, an Si platform portion 61 and a p-type Si layer 62 coupled to the optical waveguides 151 and 152, respectively. The p-type Si layer 62 is formed by implanting B ions into the Si platform portion 61. The Si platform portions 61 and the optical waveguides 151 and 152 are provided in a common Si layer 101.

[0042] The Ge-PDs 161 and 162 each further include, for example, an island-shaped i-type Ge layer 63, a two-dimensionally grown i-type Ge layer 64, and an n-type Ge layer 65. The island-shaped i-type Ge layer 63 and the two-dimensionally grown i-type Ge layer 64 are provided on the p-type Si layer 62. The n-type Ge layer 65 is formed by implanting P ions into the two-dimensionally grown i-type Ge layer 64. The PIN photodiode includes a stack including the p-type Si layer 62, the island-shaped i-type Ge layer 63, the two-dimensionally grown i-type Ge layer 64, and the n-type Ge layer 65. In the PIN photodiode, the island-shaped i-type Ge layer 63, which is actually p-type and does not include a depletion layer, has a small thickness, and the two-dimensionally grown i-type Ge film 64 with a large thickness serves as a depletion layer, which improves the sensitivity.

[0043] Ge-PD 161 and 162 further include, for example, an n-side electrode 66 in contact with the n-type Ge layer 65 and a p-side electrode 67 in contact with the p-type Si layer 62, respectively. The p-side electrode 67 of Ge-PD 161 and the n-side electrode 66 of Ge-PD 162 are connected to each other through wiring, and the wiring connecting the p-side circuit 67 of Ge-PD 161 and the n-side circuit 66 of Ge-PD 162 is connected to the input terminal of the transimpedance amplifier 163.

[0044] The transimpedance amplifier 163 performs impedance conversion and amplification on the current signals photoelectrically converted by Ge-PD 161 and 162, and outputs the beat signal Sbt as a voltage signal. (Third bare chip 300)

[0045] As Figure 1 shown, for example, the third bare chip 300 includes a controller 310, a DAC 320, an ADC 330, and a fast Fourier transform (FFT) 340. The FFT 340 corresponds to a specific example of the "signal processor for processing the beat signal" according to an embodiment of the present invention. In some examples, the third bare chip 300 is referred to as including a logic circuit that outputs an electronic signal for controlling the output control laser 210 to generate an optical signal (e.g., a chirp signal). In some cases, the controller 310 corresponds to or forms a part of the logic circuit.

[0046] The controller 310 generates, for example, control signals for controlling the laser 210, the modulator 110, the antenna 140, and the detector 160, and outputs the control signals to the DAC 320. The controller 310 also generates, for example, a control signal for controlling the ADC 330, and outputs the control signal to the ADC 330. The DAC 320 performs DA conversion on the control signals received from the controller 310, and outputs the obtained analog control signals to the laser 210, the modulator 110, the antenna 140, and the detector 160. The ADC 330 performs AD conversion on the beat signal Sbt received from the detector 160, and outputs the beat signal Sbt to the FFT 340. The FFT 340 performs FFT on the beat signal Sbt received digitally from the ADC 330 to obtain the power spectral density, and derives the frequency of the beat signal Sbt based on the obtained power spectral density. The FFT 340 outputs information (frequency information) about the derived frequency to the controller 310. The controller 310 outputs the frequency information received from the FFT 340 to the outside according to the control from the outside.

[0047] As Figures 3 to 5As shown, for example, the third bare chip 300 includes an Si substrate 301. The Si substrate 301 includes, for example, signal processing circuits such as a controller 310, a DAC 320, an ADC 330, and an FFT 340. An interlayer insulating film 302 is provided on the Si substrate 301. The interlayer insulating film 302 has the following structure: among the stacked multiple SiO2 layers, a plurality of patterned wiring layers and vias for connecting the wiring layers to each other are provided. In the interlayer insulating film 302, wirings and vias in the signal processing circuits, wirings and vias for electrically connecting the signal processing circuits to the first bare chip 100 and the second bare chip 200, etc. are provided. [Manufacturing method]

[0048] Next, the manufacturing method of the distance measuring device 1000 will be described.

[0049] Figures 11 to 20 These are cross-sectional views for explaining the manufacturing process of the distance measuring device 1000. First, an SOI substrate 106 ( Fig.11 ) is prepared. The SOI substrate 106 includes a substrate in which a BOX layer 103 and an Si layer 101 are sequentially provided on an Si substrate 104. Next, optical waveguides WG1, WG2, and WG3, a splitter 120, a circulator 130, an Si antenna 141, a coupler 150, and a part of Ge-PD 161 and 1662 (Si platform portion 61 and p-type Si layer 62) are formed in the Si layer 101 of the SOI substrate 106 ( Fig.11 ). Next, an interlayer insulating film 102 is formed on the SOI substrate 106 ( Fig.11 ).

[0050] Next, the SOI substrate 106 and the third bare chip 300 are bonded together so that the front surfaces of the interlayer insulating film 102 and the interlayer insulating film 302 face each other ( Fig.11 and Fig.12 ). Next, the Si substrate 104 in the SOI substrate 106 is removed ( Fig.13 ). Thus, the PIC substrate 100A is formed on the third bare chip 300. Then, the PIC substrate 100A and the laser substrate 230 are bonded together so that the front surface of the BOX layer 103 and the front surface of the semiconductor substrate 201 face each other ( Fig.14 and Fig.15 ). Next, the Si substrate 202 in the laser substrate 230 is removed ( Fig.16 ). Thus, the second bare chip 200 is formed on the first bare chip 100.

[0051] Next, via openings H1 to H6 are formed in the semiconductor substrate 201 ( Fig.17 and Fig.18)。Therefore, the contact layer 211 is exposed on the bottom surface of the via opening H1, the contact layer 212 is exposed on the bottom surface of the via opening H2, the wiring layer in the interlayer insulating film 302 is exposed on the bottom surface of the via opening H3, and the Si substrate 301 is exposed on the bottom surface of the via opening H4. In addition, the wiring layer in the interlayer insulating film 302 is exposed on the bottom surface of the via opening H5, and the wiring layer electrically connected to the Ge-PD 161 is exposed on the bottom surface of the via opening H6.

[0052] Next, metal is buried in the via openings H1 to H6 ( Fig.19 and Fig. 20 ). Thus, vias 411, 412, 421, 422, 431, and 432 are formed. Then, metal connecting the via 411 and the via 412 to each other, metal connecting the via 421 and the via 422 to each other, and metal connecting the via 431 and the via 432 to each other are formed ( Fig.19 and Fig. 20 ). Thus, wiring layers 413, 423, and 433 are formed. Finally, the lens 220 is provided. Thus, the distance measuring device 1000 is manufactured. Effect

[0053] Next, the effect of the distance measuring device 1000 will be described.

[0054] In the present embodiment, the second bare chip 200 (laser 210) is electrically connected to the third bare chip 300 (signal processing circuit) through the wirings 410 and 420. In addition, the first bare chip 100 (detector 160) is electrically connected to the third bare chip 300 (signal processing circuit) through the wiring 430. This enables the heat generated in the laser 210 and the heat generated in the detector 160 to be discharged to the Si substrate 301 through the wirings 410, 420, and 430. Therefore, it is possible to suppress the operation instability caused by the heat generation in the laser 210 and the detector 160.

[0055] In the present embodiment, parts of the wirings 410, 420, and 430 include the vias 411, 412, 421, 422, 431, and 432. This enables the cross-sectional areas of the wirings 410, 420, and 430 to be increased compared to the wiring layers formed by patterning, which enables the heat generated in the laser 210 and the heat generated in the detector 160 to be effectively discharged to the Si substrate 301. Therefore, it is possible to suppress the operation instability caused by the heat generation in the laser 210 and the detector 160.

[0056] In this embodiment, in the PIC substrate 100A, the optical waveguide WG1, the optical splitter 120, the optical waveguides WG2 and WG3, the coupler 150, and the Ge-PDs 161 and 162 are provided in the common Si layer 101. In addition, the controller 310, the DAC 320, the ADC 330, and the FFT 340 are provided in the third bare chip 300 (signal processing substrate). Further, the PIC substrate 100A and the second bare chip 200 are stacked on the third bare chip 300 and are electrically connected to the third bare chip 300 through the wirings 410, 420, and 430. Compared with a module in which a plurality of RF components are optically coupled, this enables size reduction. By reducing the size, the electrical signal path after the Ge-PDs 161 and 162 is shortened, which enables reduction of external noise mixing into the electrical signal.

[0057] In this embodiment, the modulator 110 and the Si antenna 141 are provided in the Si layer 101. The modulator 110 generates a transmission signal Stx (chirp signal). The Si antenna 141 outputs the transmission signal Stx1 separated from the transmission signal Stx to the outside and receives the return signal Srx from the outside. Compared with a module in which a plurality of RF components are optically coupled, this enables size reduction.

[0058] In this embodiment, the diffraction grating 105 is provided at a position opposite to the laser 210 (directly below the laser 210). The diffraction grating 105 guides the laser L emitted from the laser 210 into the optical waveguide WG1. Compared with a module in which a plurality of RF components are optically coupled, this enables size reduction. By reducing the size, the propagation path of the laser L is shortened, which enables reduction of the loss of the laser L. <2. Variation of the First Embodiment>

[0059] Next, a variation of the distance measuring device 1000 according to the above embodiment will be described. [Variation 2-1]

[0060] Fig.21 An exemplary cross-sectional structure of the distance measuring device 1000 according to the variation is shown. Fig.21 Shown is Figure 5 a variation of the cross-sectional structure. In the above embodiment, for example, as Fig.21 shown, the via 422 can be in contact with the wiring layer 423 and the wiring layer in the interlayer insulating film 302. Even in this case, the heat generated in the laser 210 can be discharged to the Si substrate 301 through the wiring 420 including the via 422. Therefore, unstable operation caused by heat generation in the laser 210 can be suppressed. [Variation 2-2]

[0061] Fig. 22 An exemplary cross-sectional configuration of the distance measuring device 1000 according to a modified example is shown. Fig. 22 Shown is Figure 5 A modified example of the cross-sectional configuration shown. In the above-described embodiments and modified examples, for example, as Fig. 22 shown, in the interlayer insulating film 102 of the PIC substrate 100A, a heat dissipation member 107 may be provided at a position opposite to the laser 210 (directly below the laser 210). The heat dissipation member 107 may include a metal (e.g., Cu). The heat dissipation member 107 may be provided, for example, in the same layer as another circuit wiring in the interlayer insulating film 102, and may include the same material as another wiring in the interlayer insulating film 102. The heat dissipation member 107 may be used as a part of the circuit wiring in the distance measuring device 1000, or may not be used as the circuit wiring of the distance measuring device 1000. In order to stabilize the potential of the heat dissipation member 107, a wiring connecting the heat dissipation member 107 and a constant potential wiring to each other may be provided in the interlayer insulating film 102.

[0062] In this modified example, in the interlayer insulating film 102 of the PIC substrate 100A, the heat dissipation member 107 is provided at a position opposite to the laser 210 (directly below the laser 210). This enables the heat generated in the laser 210 to be effectively discharged to the Si substrate 301 through the heat dissipation member 107. Therefore, it is possible to suppress the operation instability caused by the heat generation in the laser 210. [Modified Example 2-3]

[0063] Fig.23 An exemplary planar configuration of the distance measuring device 1000 according to a modified example is shown. Fig.24 Shown is along Fig.23 An example of a cross-sectional configuration taken along line A-A in Fig.23 and Fig.24 shown, for example, the second bare chip 200 may include a heat dissipation member 440 on the front surface of the semiconductor substrate 201. The heat dissipation member 440 may be provided separately from the wirings 410 and 420, and may include, for example, a metal (e.g., Cu). The heat dissipation member 440 may be used as a part of the circuit wiring in the distance measuring device 1000, or may not be used as the circuit wiring in the distance measuring device 1000. Fig.24 An example where the heat dissipation member 440 does not function as a part of the circuit wiring in the distance measuring device 1000 is illustrated.

[0064] The heat dissipation member 440 includes, for example, a via hole 441 and a wiring layer 442. The via hole 441 is in contact with the contact layer 211 and the wiring layer 442. The via hole 441 is provided in the semiconductor substrate 201 and extends along the stacking direction of the semiconductor substrate 201. The via hole 441 includes, for example, a metal (e.g., Cu) embedded in a via hole opening provided in the semiconductor substrate 201. The wiring layer 442 contains a metal (e.g., Cu). The wiring layer 442 is provided on the front surface of the semiconductor substrate 201 and is in contact with the via hole 441. In this case, the heat generated in the laser 210 can be effectively discharged to the outside through the heat dissipation member 440. Therefore, the operation instability caused by the heat generation in the laser 210 can be suppressed. <3. Second Embodiment>

[0065] Next, the distance measuring device 2000 according to the second embodiment of the present invention will be described. Hereinafter, the same components as those in the above embodiment are denoted by the same reference numerals. And the description thereof will be appropriately omitted. Structure

[0066] Fig.25 An exemplary schematic structure of the distance measuring device 2000 according to the second embodiment of the present invention is shown. Fig.26 An exemplary planar structure of the distance measuring device 2000 is shown. Fig. 27 Shown along Fig.26 An exemplary cross-sectional structure taken along line A-A in Fig.28 Shown along Fig.26 An exemplary cross-sectional structure taken along line B-B in Fig.29 Shown along Fig.26 An exemplary cross-sectional structure taken along line C-C in

[0067] The distance measuring device 2000 includes an FMCW LiDAR. As Fig.25 shown, for example, the distance measuring device 2000 includes a first bare chip 500, a laser chip 600, and a third bare chip 300. The first bare chip 500 is stacked on the third bare chip 300 and is connected to the third bare chip 300 through a bonding surface S4 between the first bare chip 500 and the third bare chip 300. The top surface of the first bare chip 500 serves as an incident / output surface S3. (Laser Chip 600)

[0068] The laser chip 600 is a light source chip that outputs an optical signal. The laser chip 600 is a chip-shaped edge-emitting semiconductor laser, and emits laser light L with a predetermined fixed wavelength (e.g., 1550 nm) from the end face of the active layer 601 under the control of the controller 310. The laser chip 600 is mounted in the recess 510 so that the laser light L is incident on the inner surface (optical waveguide WG1) of the recess 510 of the PIC substrate 500A to be described later. The laser chip 600 is mounted in the recess 510 so that the light spot of the laser chip 600 (the light spot generated on the end face of the active layer 601) is set at the same height as the Si layer 101 (optical waveguide WG1).

[0069] The laser chip 600 includes, for example, an active layer 601, a pair of cladding layers, a contact layer (first contact layer), and a contact layer (second contact layer). The active layer 601 is sandwiched between a pair of cladding layers in the thickness direction. The contact layer (first contact layer) is ohmically connected to one of the cladding layers, and the contact layer (second contact layer) is ohmically connected to the other cladding layer. The laser chip 600 further includes, for example, electrodes 610 and 620. The electrode 610 is in contact with the first contact layer, and the electrode 620 is electrically connected to the second contact layer through a via hole. The electrodes 610 and 620 are provided, for example, on the common surface (e.g., the bottom surface of the laser chip 600) of the laser chip 600. The electrodes 610 and 620 contain, for example, copper (Cu). The laser chip 600 is electrically connected to the third bare chip 300 (signal processing circuit) through the electrodes 610 and 620 and the wirings 710 and 720 to be described later. (First bare chip 500)

[0070] As Fig.25 shown, for example, the first bare chip 500 includes a modulator 110, a splitter 120, a circulator 130, an antenna 140, a coupler 150, and a detector 160. In the first bare chip 500, the modulator 110, the splitter 120, the circulator 130, the antenna 140, the coupler 150, and the detector 160 are provided in the PIC substrate 500A.

[0071] As Figure 27 to Figure 29As shown, for example, the PIC substrate 500A includes an Si layer 101, an interlayer insulating film 102, and a BOX layer 103. The Si layer 101 is sandwiched between the interlayer insulating film 102 and the BOX layer 103. The PIC substrate 500A is obtained by removing the Si substrate 104 from the SOI substrate 106. The BOX layer 103 includes a SiO2 layer. The interlayer insulating film 102 is a layer provided on the SOI substrate 106 and has a structure in which a plurality of patterned wiring layers are provided in a stacked plurality of SiO2 layers and vias for connecting the wiring layers to each other. The front surface of the interlayer insulating film 102 serves as the bottom surface of the first bare chip 500. The front surface of the interlayer insulating film 102 serves as the top surface of the first bare chip 500 and serves as the incident / output surface S5.

[0072] Optical waveguides WG1, WG2, and WG3 are provided in the Si layer 101. The optical waveguide WG1 extends, for example, from the inner surface (side surface) of the recess 510, which will be described later, through the modulator 110, the optical splitter 120, and the circulator 130 to the antenna 140. The optical waveguide WG2 is an optical wavelength branched from the optical waveguide WG1 in the optical splitter 120 and is coupled to one input terminal (optical waveguide 151) of the coupler 150. The optical waveguide WG3 is an optical waveguide branched from the optical waveguide WG1 in the circulator 130 and is coupled to the other input terminal (optical waveguide 152) of the coupler 150.

[0073] The lens 220 is bonded to the region (incident / output surface S5) of the front surface of the first bare chip 500 that faces the Si antenna 141. The transmission signal Stx1 is output from the incident / output surface S5, and the return signal Srx enters the incident / output surface S5. The lens 220 is bonded to the incident / output surface S5, and the transmission signal Stx is output from the antenna 140 to the outside through the lens 220 and the incident / output surface S5, and the return signal Srx enters the antenna 140 from the outside through the lens 22 and the incident / output surface S5.

[0074] The PIC substrate 500A has a recess 510 that houses the laser chip 600. The optical waveguide WG1 (Si layer 101) is exposed on the inner surface (side surface) of the recess 510. An insulating film such as an antireflection film may be provided on the inner surface (side surface) of the recess 510. The antireflection film prevents (or reduces) the reflection of light from the laser chip 600.

[0075] The first bare chip 500 includes wirings that electrically connect the laser chip 600 and the third bare chip 300 (signal processing circuit) to each other. As Figure 26 to Figure 29As shown, for example, the first bare chip 500 includes wiring 710 that contacts the electrode 610 of the laser chip 600 and wiring 720 that contacts the electrode 620 of the laser chip 600 as the above-described wiring. The wirings 710 and 720 correspond to specific examples of the "first wiring" according to an embodiment of the present invention. In the wirings 710 and 720, one wiring serves as the wiring for the cathode of the laser chip 600, and the other wiring serves as the wiring for the anode of the laser chip 600. Hereinafter, the wiring 710 serves as the wiring for the cathode of the laser chip 600, and the wiring 720 serves as the wiring for the anode of the laser chip 600. It should be noted that, depending on the structure of the laser chip 600, the wiring 710 may serve as the wiring for the anode of the laser chip 600, and the wiring 720 may serve as the wiring for the cathode of the laser chip 600.

[0076] As Figure 26 to Figure 28 shown, for example, the wiring 710 includes solder 711, via 712, and wiring layer 713. As Fig.26 , Fig. 27 and Fig.29 shown, for example, the wiring 720 includes solder 721, via 722, and wiring layer 723. The wirings 710 and 720 contain, for example, Cu. The laser chip 600 is electrically connected to the third bare chip 300 (signal processing circuit) through the wirings 710 and 720.

[0077] The solder 711 contacts the electrode 610 and the wiring layer 713. The solder 711 is provided at a position on the front surface of the wiring layer 713 that faces the bottom surface of the recess 510. The via 712 contacts the wiring layer in the wiring layer 713 and the interlayer insulating film 302. The via 712 is provided in the first bare chip 500 and the third bare chip 300 and extends from the BOX layer 103 to the interlayer insulating film 302. The via 712 includes, for example, a metal (e.g., Cu) buried in the via opening provided from the BOX layer 103 to the interlayer insulating film 302. The wiring layer 713 contacts the solder 711 and the via 712. The wiring layer 713 contains a metal (e.g., Cu) and is provided on the bottom surface and side surface of the recess 510 and the front surface of the first bare chip 500.

[0078] The solder 721 is in contact with the electrode 620 and the wiring layer 723. The solder 721 is disposed at a position on the front surface of the wiring layer 723 that faces the bottom surface of the recess 510. The via 722 is in contact with the wiring layer 723 and the Si substrate 301. The via 722 is provided in the first bare chip 500 and the third bare chip 300, and extends from the BOX layer 103 to the interlayer insulating film 302. The via 722 includes, for example, a metal (e.g., Cu) embedded in a via opening provided from the BOX layer 103 to the interlayer insulating film 302. The wiring layer 723 is in contact with the solder 711 and the via 712. The wiring layer 723 contains a metal (e.g., Cu), and is disposed on the bottom surface and side surface of the recess 510 and the front surface of the first bare chip 500.

[0079] Metal bumps can be used instead of the solder 711. Additionally, metal bumps can be used instead of the solder 721.

[0080] The first bare chip 500 further includes, for example, a wiring 430 that electrically connects the detector 160 and the third bare chip 300 (signal processing circuit) to each other. As Fig.26 and Fig.28 shown, for example, the wiring 430 includes vias 431, vias 432, and a wiring layer 433. The wiring 430 contains, for example, copper (Cu). The first bare chip 100 (detector 160) is electrically connected to the third bare chip 300 (signal processing circuit) through the wiring 430.

[0081] The via 431 is in contact with a wiring layer (e.g., Cu) in the interlayer insulating film 302 and the wiring layer 433. The via 431 extends from the BOX layer 103 to the interlayer insulating film 302. The via 431 includes, for example, a metal (e.g., Cu) embedded in a via opening provided from the BOX layer 103 to the interlayer insulating film 302. The via 432 is in contact with a wiring layer (e.g., Cu) in the interlayer insulating film 102 that is electrically connected to the detector 160 and the wiring layer 433. The via 432 extends from the BOX layer 103 to the interlayer insulating film 102. The via 432 includes, for example, a metal (e.g., Cu) embedded in a via opening provided from the BOX layer 103 to the interlayer insulating film 102. The wiring layer 433 is disposed on the front surface of the BOX layer 103, and is in contact with the via 431 and the via 432. The wiring layer 433 contains a metal (e.g., Cu). Effect

[0082] Next, the effects of the distance measuring device 2000 will be described.

[0083] In the present embodiment, the laser chip 600 is electrically connected to the third bare chip 300 (signal processing circuit) through the wirings 710 and 720. In addition, the first bare chip 500 (detector 160) is electrically connected to the third bare chip 300 (signal processing circuit) through the wiring 430. This makes it possible to discharge the heat generated in the laser chip 600 and the heat generated in the detector 160 to the Si substrate 301 through the wirings 710, 720, and 430. Therefore, it is possible to suppress operational instability caused by heat generation in the laser chip 600 and the detector 160.

[0084] In the present embodiment, parts of the wirings 710, 720, and 430 include vias 712, 722, 431, and 432. This makes it possible to increase the cross-sectional area of ​​the wirings 710, 720, and 430 compared to a wiring layer formed by patterning, which makes it possible to effectively discharge the heat generated in the laser chip 600 and the heat generated in the detector 160 to the Si substrate 301. Therefore, it is possible to suppress operational instability caused by heat generation in the laser chip 600 and the detector 160.

[0085] In the present embodiment, in the PIC substrate 500A, the optical waveguide WG1, the optical splitter 120, the optical waveguides WG2 and WG3, the coupler 150, and the Ge-PDs 161 and 162 are arranged in a common Si layer 101. In addition, the controller 310, the DAC 320, the ADC 330, and the FFT 340 are arranged in the third bare chip 300 (signal processing substrate). In addition, the PIC substrate 500A is stacked on the third bare chip 300 and is electrically connected to the third bare chip 300 through wiring 710, 720, and 430. Compared with a module in which a plurality of RF components are connected by optical fibers, this enables a reduction in size. The electrical signal path after the Ge-PDs 161 and 162 is shortened by reducing the size, which enables a reduction in external noise mixed into the electrical signal.

[0086] In the present embodiment, the recess 510 accommodating the laser chip 600 is provided in the PIC substrate 500A, and the laser light L emitted from the laser chip 600 is introduced from the end of the optical waveguide WG1 (Si layer 101) exposed on the inner surface (side) of the recess 510. This enables a reduction in size compared to a module in which a plurality of RF components are connected by optical fibers. The propagation path of the laser light L is shortened by reducing the size, which enables a reduction in the loss of the laser light L. <4. Modification of the Second Implementation Example>

[0087] Next, a modification of the distance measuring device 2000 according to the second embodiment will be described. [Variation 4-1]

[0088] Fig.30Shows an exemplary cross-sectional structure of the distance measuring device 2000 according to a modified example. Fig.30 Shows Fig.29 a modified example of the cross-sectional structure. In the above second embodiment, as Fig.30 shown, the via hole 722 can be in contact with the wiring layer 723 and the wiring layer in the interlayer insulating film 302. Even in such a case, heat generated in the laser chip 600 can be discharged to the Si substrate 301 through the wiring 720 including the via hole 722. Therefore, it is possible to suppress the operation instability caused by heat generation in the laser chip 600. [Modified Example 4-2]

[0089] Fig.31 And Fig.32 respectively show an exemplary cross-sectional structure of the distance measuring device 2000 according to a modified example. Fig.31 And Fig.32 respectively show Fig.28 a modified example of the cross-sectional structure shown. In the above second embodiment and its modified examples, for example, as Fig.31 And 32 shown, a groove portion 520 can be provided on the bottom surface of the recess 510. As Fig.31 shown, the groove portion 520 can have a depth penetrating the PIC substrate 500A. For example, as Fig.32 shown, the groove portion 520 can have a depth penetrating not only the PIC substrate 500A but also the interlayer insulating film 302.

[0090] The groove portion 520 is provided at least in such a region that in a plan view, it is the region of the bottom surface of the recess 510 located between the optical waveguide WG1 and the laser chip 600. As Fig.33 shown, the groove portion 520 can have, for example, a length in a plan view spanning the region of the bottom surface of the recess 510 located between the optical waveguide WG1 and the laser chip 600. Additionally, for example, as Fig.34 And Fig.35 shown, in a plan view, the groove portion 520 can be provided to surround three sides including the light emitting surface of the laser chip 600. In such a case, for example, as Fig.34 shown, a plurality of groove portions 520 can be provided for each of the three sides of the laser chip 600. Or, for example, as Fig.35 shown, one groove portion 520 can have a U shape surrounding three sides including the light emitting surface of the laser chip 600.

[0091] Therefore, in this modified example, in the plan view, the groove portion 520 is provided at least in a region of the bottom surface of the recessed portion 510 that is located between the optical waveguide WG1 and the laser chip 600. Therefore, the groove portion 520 makes it difficult for the heat generated in the laser chip 600 to be propagated to the optical waveguide WG1. Therefore, it is possible to suppress the operation instability caused by the heat generation in the laser chip 600. In other words, in this modified example, the groove portion 520 is used to prevent the heat generated by the laser chip 600 from being propagated to the waveguide WG1.

[0092] In this modified example, for example, as Fig.36 and Fig.37 shown, the resin member 530 may be buried in the recessed portion 510 and the groove portion 520. The resin member 530 includes a resin material (transparent resin material) that allows laser light to pass through, and includes, for example, epoxy resin, acrylic resin, or acrylate. By burying the resin member 530 in the recessed portion 510 and the groove portion 520 in this way, it is possible to suppress the detachment of the laser chip 600 or the displacement of the laser chip 600. Therefore, it is possible to suppress the operation instability caused by the reduction of the optical coupling characteristics between the laser chip 600 and the optical waveguide WG1. [Modified Example 4-3]

[0093] Fig.38 and Fig.39 respectively show exemplary cross-sectional configurations of the distance measuring device 2000 according to the modified example. Fig.38 Shows Fig.28 a modified example of the cross-sectional configuration shown. Fig.39 Shows Fig.29 a modified example of the cross-sectional configuration shown. In the above second embodiment and its modified examples, for example, as Fig.38 shown, a via opening 540 may be provided on the bottom surface of the recessed portion 510. For example, as Fig.38 shown, the via opening 540 may have a depth that penetrates the PIC substrate 500A and reaches the wiring layer in the interlayer insulating film 302. In this case, the wiring layer in the interlayer insulating film 302 is exposed on the bottom surface of the via opening 540. In addition, in the above second embodiment and its modified examples, for example, as Fig.39 shown, a via opening 550 may be provided on the bottom surface of the recessed portion 510. For example, as Fig.39 shown, the via opening 550 may have a depth that penetrates the PIC substrate 500A and the interlayer insulating film 302 and reaches the Si substrate 301. In this case, the Si substrate 301 is exposed on the bottom surface of the via opening 550.

[0094] In this modified example, the wiring 710 in contact with the electrode 610 of the laser chip 600 extends from the bottom surface of the recess 510 along the side surface and the bottom surface of the via opening 540. The wiring 710 contacts the wiring layer in the interlayer insulating film 302 through the via opening 540. It should be noted that the portion of the wiring 710 extending along the side surface and the bottom surface of the via opening 540 corresponds to a via.

[0095] In this modified example, the wiring 720 in contact with the electrode 620 of the laser chip 600 extends from the bottom surface of the recess 510 to the side surface and the bottom surface of the via opening 550. The wiring 720 contacts the Si substrate 301 through the via opening 550. It should be noted that the portion of the wiring 720 extending along the side surface and the bottom surface of the via opening 550 corresponds to a via.

[0096] Therefore, in this modified example, the wiring 710 contacts the wiring layer in the interlayer insulating film 302 through the via opening 540, and the wiring 720 contacts the Si substrate 301 through the via opening 550. This enables the wirings 710 and 720 not only to electrically connect the laser chip 600 and the controller 310 to each other, but also to discharge the heat generated in the laser chip 600 to the Si substrate 301 through the wirings 710 and 720. Therefore, it is possible to suppress the operation instability caused by the heat generation in the laser chip 600. [Modified Example 4-4]

[0097] Fig.40 and Fig.41 respectively show exemplary cross-sectional configurations of the distance measuring device 2000 according to the modified example. Fig.40 shows Fig.28 a modified example of the cross-sectional configuration shown. Fig.41 shows Fig.29 a modified example of the cross-sectional configuration shown. In the above second embodiment and its modified examples, for example, as Fig.40 and Fig.41 shown, the first bare chip 500 and the third bare chip 300 are bonded together to bond the pad electrodes 561, 562, and 563 provided on the first bare chip 300 (PIC substrate 500A) and the pad electrodes 303, 304, and 305 on the third bare chip 300 (interlayer insulating film 302) to each other.

[0098] The pad electrodes 561 form part of the wiring 710 and are electrically connected to the wiring layer 713. The wiring layer 713 electrically connects the laser chip 600 and the pad electrodes 561 to each other. The pad electrode 562 is electrically connected to the Ge-PD 161, for example. The pad electrode 563 forms part of the wiring 720 and is electrically connected to the wiring 723. The wiring layer 723 electrically connects the laser chip 600 and the pad electrode 563 to each other. The pad electrodes 303, 304, 305, 561, 562, and 563 each include a metal (e.g., a copper pad). The wirings 710 and 720 electrically connect the laser chip 600 and the third bare chip 300 (interlayer insulating film 302) to each other, respectively. The wirings 710 and 720 correspond to specific examples of the "second wiring" according to the first embodiment of the present invention.

[0099] For example, as Fig.40 and Fig.41 shown, the wiring layers 713 and 723 can be electrically connected to the pad electrodes 561 and 563 through openings provided on the bottom surface of the recess 510. A part of the wiring layers 713 and 723 can include a metal material different from that of the pad electrodes 303, 304, 305, 561, 562, and 563. A part of the wiring layers 713 and 723 can include a material having high heat dissipation (e.g., aluminum (Al)) compared with the materials of the pad electrodes 303, 304, 305, 561, 562, and 563.

[0100] Therefore, in this modification, the first bare chip 500 and the third bare chip 300 are bonded together so that the pad electrodes 561, 562, and 563 are in contact with the pad electrodes 303, 304, and 305, respectively. Even in this case, the heat generated in the laser chip 600 and the heat generated in the detector 160 can be discharged to the Si substrate 301 through the wirings 710 and 720 and the pad electrodes 562 and 304. Therefore, it is possible to suppress the operation instability caused by the heat generation in the laser 210 and the detector 160.

[0101] In this modification, for example, as Fig.42 、 Figure 43 and Figure 44 shown, the groove portion 520 can be provided on the bottom surface of the recess 510. The groove portion 520 can have a depth penetrating the PIC substrate 500A, for example, or can have a depth penetrating not only the PIC substrate 500A but also the interlayer insulating film 302.

[0102] The groove portion 520 is provided at least in the region of the bottom surface of the recess 510 that is located between the optical waveguide WG1 and the laser chip 600 in the plan view. As Figure 42As shown, in the plan view, the groove portion 520 may have, for example, a length in a region between the optical waveguide WG1 and the laser chip 600 that spans the bottom surface of the recess 510. Further, for example, as Figure 43 and Figure 44 shown, in the plan view, the groove portion 520 may be provided to surround four side surfaces including the light emitting surface of the laser chip 600. In this case, for example, as Figure 43 shown, a plurality of groove portions 520 may be provided for each of the four side surfaces of the laser chip 600. Alternatively, for example, as Figure 44 shown, one groove portion 520 may have an annular shape surrounding the laser chip 600.

[0103] Therefore, in this modification, when the groove portion 520 is provided at least in the region of the bottom surface of the recess 510 that is located between the optical waveguide WG1 and the laser chip 600 in the plan view, the groove portion 520 makes it difficult for the heat generated in the laser chip 600 to propagate to the optical waveguide WG1. Therefore, it is possible to suppress the operation instability caused by the heat generation in the laser chip 600.

[0104] In this modification, the resin member 530 may be embedded in the recess 510 and the groove portion 520. Embedding the resin member 530 in the recess 510 and the groove portion 520 in this way makes it possible to prevent (or reduce) the laser chip 600 from falling off or the laser chip 600 from being displaced. Therefore, it is possible to suppress the operation instability caused by the reduction in the optical coupling characteristics between the laser chip 600 and the optical waveguide WG1. [Modification 4-5]

[0105] Figure 45 and Figure 46 respectively show exemplary cross-sectional configurations of the distance measuring device 2000 according to the modification. Figure 45 Shows Figure 28 a modification of the cross-sectional configuration shown. Figure 46 Shows Figure 29 a modification of the cross-sectional configuration shown. In the above second embodiment and its modifications, the first bare chip 500 may not be stacked on the third bare chip 300, and the first bare chip 500 and the third bare chip 300 may be separately provided. In this case, for example, as Figure 45 shown, the wiring 710 may be electrically connected to the third bare chip 300 (signal processing circuit) through the bonding wire 571. The bonding wire 571 contacts, for example, the wiring layer 713. For example, as Figure 45 shown, the wiring 430 may be electrically connected to the third bare chip 300 (signal processing circuit) through the bonding wire 572. The bonding wire 572 contacts, for example, the front surface of the wiring layer 433. The bonding wires 571 and 572 contain, for example, gold (Au).

[0106] In this modified example, for instance, as Figure 45 and Figure 46 shown, the PIC substrate 500A is stacked on the support substrate 580. In this case, the front surface on the side of the interlayer insulating film 102 of the PIC substrate 500A serves as the incident / output surface S5. Additionally, in the wiring 720, the via 722 is in contact with the support substrate 580. It should be noted that in the wiring 720, the via 722 can be omitted, and the wiring 720 can be electrically connected to the third bare chip 300 (signal processing circuit) through the bonding wire 572.

[0107] In this modified example, the first bare chip 500 and the third bare chip 300 are separately arranged. In this case, the heat generated in the laser chip 600 and the heat generated in the detector 160 can be discharged to the outside through the wirings 710, 720, and 430 and the bonding wires 571 and 572. Therefore, the operation instability caused by the heat generation in the laser chip 600 and the detector 160 can be suppressed.

[0108] In this modified example, for instance, as Figure 47 shown, the wiring 720 can be in contact with the support substrate 580 through the connection wiring 724 provided in the opening on the bottom surface of the recess 510. In this case, the heat generated in the laser chip 600 can be effectively discharged to the support substrate 580 through the connection wiring 724. Therefore, the operation instability caused by the heat generation in the laser chip 600 can be suppressed. [Modified Example 4-6]

[0109] Figure 48 Shows an exemplary planar configuration of the laser chip 600 and the recess 510 of the distance measuring device 2000 according to the modified example. Figure 49 Shows an exemplary cross-sectional configuration of the laser chip 600 and the recess 510 of the distance measuring device 2000 according to the modified example. In the above second embodiment and its modified examples, for instance, as Figure 48 shown, in the plan view, the surface (side surface 510a) of the inner surface (side surface) of the recess 510 where the light (laser L) of the laser chip 600 is incident can be set to be not directly opposite to the light emitting surface of the laser chip 600, but inclined relative thereto. The side surface 510a is the surface among the inner surfaces (side surfaces) of the recess 510 that is adjacent to the light emitting surface of the laser chip 600. Additionally, in the above second embodiment and its modified examples, for instance, as Figure 49 shown, in the vertical cross-sectional view, the surface (side surface 510a) among the inner surfaces (side surfaces) of the recess 510 that is adjacent to the light emitting surface of the laser chip 600 can be set to be not directly opposite to the light emitting surface of the laser chip 60 but inclined relative thereto.

[0110] In addition, in the second embodiment and its modified examples described above, an insulating film 590 such as an antireflection film may cover the side surface 510a. The antireflection film prevents (or reduces) the reflection of light from the laser chip 600. For example, as Figure 48 and Figure 49 shown, the waveguide 602 that causes laser oscillation in the active layer 601 and the optical waveguide WG1 may be arranged on the same straight line. This makes it possible to prevent (or reduce) the light reflected by the side surface 510a of the laser L emitted from the laser chip 600 from directly entering the active layer 601 as return light. Therefore, it is possible to suppress the operation instability caused by the return light.

[0111] In a modified example, for example, the waveguide 602 and the optical waveguide WG1 may be arranged on a line parallel to the normal of the side surface 510a. Even in this case, it is possible to prevent (or reduce) the light reflected by the side surface 510a of the laser L emitted from the laser chip 600 from directly entering the active layer 601 as return light. Therefore, it is possible to suppress the operation instability caused by the return light. [Modified Examples 4-7]

[0112] Figure 51 An exemplary cross-sectional configuration of the laser chip 600 and the recess 510 in the distance measuring device 2000 according to the modified example is shown. In the second embodiment and its modified examples described above, for example, as Figure 51 shown, a recess 591 may be provided on the bottom surface of the recess 510. The recess 591 adjusts the position of the laser chip 600. The recess 591 has a configuration that enables adjustment of the position of one or more protrusions 630 provided on the laser chip 600, and is, for example, a triangular groove or a mortar-shaped groove. Providing the recess 591 on the bottom surface of the recess 510 in this way enables adjustment of the position of the laser chip 600. Therefore, it is possible to accurately arrange the laser chip 600 at a desired position, which makes it possible to suppress the operation instability caused by a decrease in the optical coupling characteristics between the laser chip 600 and the optical waveguide WG1.

[0113] Figure 52 An exemplary planar configuration of the laser chip 600 and the recess 510 of the distance measuring device 2000 according to the modified example is shown. Figure 53 Shows an exemplary cross-sectional configuration taken along the line A-A in Figure 52 . Figure 54 (A) of Figure 52 shows an exemplary planar configuration of the recess 510 in the case where the laser chip 600 is removed in Figure 54 . (B) of

[0114] In this modified example, for example, asFigure 52 , Figure 53 and Figure 54 As shown in Figure 54 , a plurality of recesses 592 can be provided on the bottom surface of the recess 510. The recesses 592 respectively adjust the position of the laser chip 600. Each recess 592 is provided at a position opposite to one of the four corners of the laser chip 600, and, for example, has an L shape in a plan view. It should be noted that Figure 52 and Figure 54 illustrate the case where two recesses 592 are provided on the bottom surface of the recess 510.

[0115] In this modification, for example, as shown in Figure 52 , Figure 53 and Figure 54 shown, a protrusion 593 can also be provided at a position adjacent to the recess 592. The protrusion 593 adjusts the height of the laser chip 600. The protrusion 593 also serves as, for example, the side wall of the recess 592 and has, for example, a W shape in a plan view. It should be noted that Figure 52 and Figure 54 illustrate the case where two protrusions 593 are provided on the bottom surface of the recess 510.

[0116] In this modification, providing two recesses 592 on the bottom surface of the recess 510 enables adjustment of the position of the laser chip 600 in the rotational direction in a plan view. Further, in this modification, providing the protrusion 593 that also serves as the side wall of the recess 592 enables adjustment of the height of the laser chip 600. Accordingly, the laser chip 600 can be accurately arranged at a desired position, which makes it possible to suppress operation instability caused by a decrease in the optical coupling characteristics between the laser chip 600 and the optical waveguide WG1. [Modification 4-8]

[0117] Figure 55 FIG. Figure 55 shows a cross-sectional example of the laser chip 600 and the recess 510 of the distance measuring device 2000 according to the modification. In the above-described second embodiment and its modifications, for example, as shown in Figure 55 shown, one or more protrusions 594 can be provided on the bottom surface of the recess 510. The one or more protrusions 594 adjust the height of the laser chip 600. The plurality of protrusions 594 are provided, for example, at positions adjacent to the wiring layers 713 and 723. Accordingly, the laser chip 600 can be accurately arranged at a desired position, which makes it possible to suppress operation instability caused by a decrease in the optical coupling characteristics between the laser chip 600 and the optical waveguide WG1. [Modification 4-9]

[0118] Figure 56 FIG. Figure 56 shows an exemplary cross-sectional configuration of the distance measuring device 2000 according to the modification. In the above-described second embodiment and its modifications, for example, as shown inFigure 56 As shown, the PIC substrate 500A may include, for example, an optical waveguide WGa separated from the optical waveguide WG1.

[0119] In the PIC substrate 500A, the optical waveguide WGa is disposed in, for example, a layer different from the layer including the optical waveguide WG1 (e.g., the BOX layer 103). The optical waveguide WGa is disposed in the layer 101a containing a material having a refractive index equal to or greater than the refractive index of SiO2 (1.44) and equal to or less than the refractive index of Si (3.45). For example, the optical waveguide WGa may be disposed in the layer 101a containing a material such as Ta2O5, Nb2O2, ZnO, TeO2, CeO2, or Al2O3 having a refractive index equal to or greater than 2.0 and less than the refractive index of Si (3.45). Disposing the optical waveguide WGa in the layer 101a containing such a material enables obtaining a high-quality optical waveguide WGa with few defects.

[0120] The laser L emitted from the laser chip 600 is incident on the optical waveguide WGa. The diffraction grating 501 is disposed at a position of the optical waveguide WGa opposite to the diffraction grating 502 of the optical waveguide WG1 (a portion directly above the diffraction grating 502). For example, the diffraction grating 501 is an element in which a plurality of grooves or through holes are arranged side by side in a row at a pitch of several hundred nm in the layer 101a. The diffraction grating 501 outputs the laser L propagating through the optical waveguide WGa toward the diffraction grating 502. The diffraction grating 502 is, for example, an element in which a plurality of grooves or through holes are arranged side by side in a row at a pitch of several hundred nm in the optical waveguide WG1. The diffraction grating 502 guides the laser L output from the optical waveguide WGa into the optical waveguide WG1. The laser L propagating through the optical waveguide WG1 is input to the modulator 110.

[0121] In the PIC substrate 500A, the reflective layer 503 may be disposed at a position opposite to the diffraction grating 501, and the diffraction grating 502 is disposed between the reflective layer 503 and the diffraction grating 501 (i.e., directly below the diffraction grating 501). The reflective layer 503 functions as follows: It reflects the light in the laser L output from the diffraction grating 501 that has passed through the diffraction grating 502 without being introduced into the diffraction grating 502 to return the light to the diffraction grating 502. The reflective layer 503 is disposed, for example, in the interlayer insulating film 102. The reflective layer 503 contains a metal (e.g., Cu).

[0122] In this modification, in the PIC substrate 500A, the optical waveguide WGa is disposed separately from the optical waveguide WG1. Therefore, a material suitable for capturing the laser L emitted from the laser chip 600 can be selected as the material of the optical waveguide WGa. Compared with the case where the laser L is directly captured in the optical waveguide WG1, this enables obtaining a high-quality optical waveguide WGa with few defects, which enables suppressing operation instability caused by crystal defects. [Modification Example 4 - 10]

[0123] Figure 57 and Figure 58 respectively show exemplary cross - sectional configurations of the distance - measuring device 2000 according to the modification example. In the above - mentioned second embodiment and its modification examples, a cutout section 511 for accommodating the laser chip 600 may be provided in the PIC substrate 500A instead of the recess 510. Even in this case, effects similar to those of the above - mentioned second embodiment and its modification examples can be achieved.

[0124] It should be noted that the pad electrodes 303, 304 and 305, the wirings 410, the vias 411 and 412, the wiring layer 413, the wiring 420, the vias 421 and 422, the wiring layer 423, the wiring 430, the vias 431 and 432, the wiring layer 433, the heat - dissipating member 440, the via 441, the wiring layer 442, the electrodes 610 and 620, the wiring 710, the via 712, the wiring layer 713, the wiring 720, the via 722, the wiring layer 723 and the connection wiring 724 are not limited to the above - mentioned materials, and for example, may respectively have a stacked structure including W, Al, Cu, Ag or their alloys and barrier metals (e.g., TiN, Ti, Ta or TaN). <5. Application Example>

[0125] The technology according to the present invention can be applied to various products. For example, the technology according to the present invention can be implemented in the form of a device installed on any type of moving body such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, a personal mobility device, an aircraft, a drone, a ship, a robot, a construction machine, and an agricultural machine (tractor).

[0126] Figure 59 is a block diagram showing a schematic configuration example of a vehicle control system 7000 as an example of a moving - body control system to which the technology according to the present invention is applied. The vehicle control system 7000 includes a plurality of electronic control units connected to each other via a communication network 7010. In Figure 59 the example shown, the vehicle control system 7000 includes a drive - system control unit 7100, a body - system control unit 7200, a battery - control unit 7300, an outside - vehicle - information detection unit 7400, an inside - vehicle - information detection unit 7500, and an integrated - control unit 7600. The communication network 7010 connecting the plurality of control units can be, for example, a vehicle - mounted communication network conforming to any standard such as Controller Area Network (CAN), Local Interconnect Network (LIN), Local Area Network (LAN), or FlexRay (registered trademark).

[0127] Each control unit includes: a microcomputer that performs arithmetic processing according to various types of programs; a storage unit that stores programs executed by the microcomputer, parameters for various types of operations, etc.; and a drive circuit that drives various types of controlled target devices. Each control unit further includes: a network interface (I / F) for communicating with other control units via a communication network 7010; and a communication I / F for communicating with devices, sensors, etc. inside and outside the vehicle by wired communication or radio communication. Figure 59 The functional configuration of the illustrated integrated control unit 7600 includes a microcomputer 7610, a general-purpose communication I / F 7620, a dedicated communication I / F 7630, a positioning unit 7640, a beacon receiving unit 7650, a vehicle-mounted device I / F 7660, a sound / image output unit 7670, a vehicle-mounted network I / F 7680, and a storage unit 7690. Other control units similarly include a microcomputer, a communication I / F, a storage unit, etc.

[0128] The drive system control unit 7100 controls the operation of devices related to the drive system of the vehicle according to various types of programs. For example, the drive system control unit 7100 serves as a control device for the following devices: a driving force generation device such as an internal combustion engine, a drive motor, etc. that generates the driving force of the vehicle; a driving force transmission mechanism that transmits the driving force to the wheels; a steering mechanism that adjusts the steering angle of the vehicle; and a braking device that generates the braking force of the vehicle, etc. The drive system control unit 7100 may have the function of a control device for an anti-lock braking system (ABS) or electronic stability control (ESC), etc.

[0129] The drive system control unit 7100 is connected to the vehicle state detection unit 7110. For example, the vehicle state detection unit 7110 includes at least one of a gyro sensor that detects the angular velocity of the axial rotational movement of the vehicle body, an acceleration sensor that detects the acceleration of the vehicle, and sensors for detecting the operation amount of the accelerator pedal, the operation amount of the brake pedal, the steering angle of the steering wheel, the engine speed, or the rotational speed of the wheels, etc. The drive system control unit 7100 performs arithmetic processing using the signals input from the vehicle state detection section 7110, and controls the internal combustion engine, the drive motor, the electric power steering device, the braking device, etc.

[0130] The vehicle body system control unit 7200 controls the operations of various types of devices provided to the vehicle body according to various types of programs. For example, the vehicle body system control unit 7200 serves as a control device for a keyless entry system, a smart key system, an electric window device, or various types of lights such as headlamps, reverse lamps, brake lamps, turn signal lamps, and fog lamps. In this case, radio waves transmitted from a mobile device that substitutes for a key or signals from various types of switches can be input to the vehicle body system control unit 7200. The vehicle body system control unit 7200 receives these input radio waves or signals and controls the vehicle's door lock device, electric window device, lights, etc.

[0131] The battery control unit 7300 controls the storage battery 7310 that serves as a power source for driving an electric motor according to various types of programs. For example, information about the battery temperature, battery output voltage, remaining battery charge, etc. is provided from the battery device including the storage battery 7310 to the battery control unit 7300. The battery control unit 7300 performs arithmetic processing using these signals and performs control for adjusting the temperature of the storage battery 7310 or controls a cooling device supplied to the battery device, etc.

[0132] The vehicle exterior information detection unit 7400 detects information about the exterior of the vehicle including the vehicle control system 7000. For example, the vehicle exterior information detection unit 7400 is connected to at least one of a camera unit 7410 and a vehicle exterior information detection unit 7420. The camera unit 7410 includes at least one of a time-of-flight (ToF) camera, a stereo camera, a monocular camera, an infrared camera, and other cameras. The vehicle exterior information detection unit 7420 includes, for example, at least one of an environmental sensor for detecting the current atmospheric conditions or weather conditions and a peripheral information detection sensor for detecting other vehicles, obstacles, pedestrians, etc. in the periphery of the vehicle including the vehicle control system 7000.

[0133] For example, the environmental sensor can be at least one of a rain drop sensor for detecting rainfall, a fog sensor for detecting fog, a sunshine sensor for detecting the degree of sunshine, and a snow sensor for detecting snowfall. The peripheral information detection sensor can be at least one of an ultrasonic sensor, a radar device, and a LIDAR device (light detection and ranging device, or laser vision detection and ranging device). Each of the camera unit 7410 and the vehicle exterior information detection unit 7420 is provided as an independent sensor or device, or as a device in which a plurality of sensors or devices are integrated.

[0134] Figure 60An example of the installation positions of the imaging unit 7410 and the vehicle exterior information detection section 7420 is shown. The imaging units 7910, 7912, 7914, 7916, and 7918 are provided, for example, at at least one of the positions of the front nose, side mirrors, rear bumper, and rear door of the vehicle 7900 and at a position above the windshield inside the vehicle. The imaging unit 7910 provided at the front nose and the imaging unit 7918 provided at the upper part of the windshield inside the vehicle mainly acquire images in front of the vehicle 7900. The imaging units 7912 and 7914 provided at the side mirrors mainly acquire images on both sides of the vehicle 7900. The imaging unit 7916 provided at the rear bumper or the rear door mainly acquires images behind the vehicle 7900. The imaging unit 7918 provided at the upper part of the windshield inside the vehicle is mainly used to detect preceding vehicles, pedestrians, obstacles, signals, traffic signs, lanes, etc.

[0135] Incidentally, Figure 60 An example of the imaging range of each of the imaging units 7910, 7912, 7914, and 7916 is shown. The imaging range a represents the imaging range of the imaging unit 7910 provided at the front nose. The imaging ranges b and c represent the imaging ranges of the imaging units 7912 and 7914 provided at the side mirrors, respectively. The imaging range d represents the imaging range of the imaging unit 7916 provided at the rear bumper or the rear door. For example, a bird's-eye view image of the vehicle 7900 viewed from above can be obtained by superimposing the image data captured by the imaging units 7910, 7912, 7914, and 7916.

[0136] The vehicle exterior information detection units 7920, 7922, 7924, 7926, 7928, and 7930 provided at the front, rear, both sides, corners of the vehicle 7900, and at the upper part of the windshield inside the vehicle can be, for example, ultrasonic sensors or radar devices. For example, the vehicle exterior information detection units 7920, 7926, and 7930 provided at the front nose, rear bumper, rear door of the vehicle 7900, and at the upper part of the windshield inside the vehicle can be LIDAR devices. These vehicle exterior information detection units 7920 to 7930 are mainly used to detect preceding vehicles, pedestrians, or obstacles, etc.

[0137] Will return Figure 59Continue the description. The vehicle exterior information detection unit 7400 causes the imaging unit 7410 to capture an image of the exterior of the vehicle and receives data of the captured image. In addition, the vehicle exterior information detection unit 7400 receives detection information from the vehicle exterior information detection unit 7420 connected to the vehicle exterior information detection unit 7400. When the vehicle exterior information detection unit 7420 is an ultrasonic sensor, a radar device, or a LIDAR device, the vehicle exterior information detection unit 7400 emits ultrasonic waves, electromagnetic waves, etc., and receives information on the received reflected waves. Based on the received information, the vehicle exterior information detection unit 7400 can perform processing for detecting objects such as people, vehicles, obstacles, signs, characters on the road surface, etc., or processing for detecting the distance to the object. The vehicle exterior information detection unit 7400 can perform environmental recognition processing such as recognizing rainfall, fog, or road surface conditions based on the received information. The vehicle exterior information detection unit 7400 can calculate the distance to an object outside the vehicle based on the received information.

[0138] In addition, based on the received image data, the vehicle exterior information detection unit 7400 can perform image recognition processing for recognizing people, vehicles, obstacles, signs, characters on the road surface, etc., or processing for detecting the distance thereto. The vehicle exterior information detection unit 7400 can perform processing such as distortion correction and alignment on the received image data, and combine the image data captured by a plurality of different imaging units 7410 to generate a bird's-eye view image or a panoramic image. The vehicle exterior information detection unit 7400 can perform viewpoint conversion processing using the image data captured by the imaging unit 7410 including different imaging units.

[0139] The vehicle interior information detection unit 7500 detects information about the interior of the vehicle. The vehicle interior information detection unit 7500 is connected to, for example, a driver state detection unit 7510 that detects the state of the driver. The driver state detection unit 7510 may include a camera that captures an image of the driver, a biosensor that detects biometric information of the driver, a microphone that collects sounds inside the vehicle, etc. The biosensor is provided, for example, on the seat surface, the steering wheel, etc., and detects biometric information of a passenger sitting on the seat or a driver holding the steering wheel. Based on the detection information input from the driver state detection unit 7510, the vehicle interior information detection unit 7500 can calculate the degree of fatigue or concentration of the driver, or can determine whether the driver is dozing off. The vehicle interior information detection unit 7500 can perform processing such as noise cancellation processing on the audio signal obtained by collecting sounds.

[0140] The integrated control unit 7600 controls the overall operation within the vehicle control system 7000 according to various types of programs. The integrated control unit 7600 is connected to the input unit 7800. For example, the input unit 7800 is implemented by a device that can be input-operated by a passenger, such as a touch panel, a button, a microphone, a switch, or a joystick. Data obtained by performing speech recognition on the speech input via the microphone can be supplied to the integrated control unit 7600. The input unit 7800 can be, for example, a remote control device using infrared rays or other radio waves, or an external connection device such as a mobile phone or a personal digital assistant (PDA) that supports the operation of the vehicle control system 7000. The input unit 7800 can be, for example, a camera. In this case, the passenger can input information by gestures. Or, data obtained by detecting the movement of the wearable device worn by the passenger can be input. In addition, the input unit 7800 can include, for example, an input control circuit or the like that generates an input signal based on the information input by the passenger or the like using the above input unit 7800 and outputs the generated input signal to the integrated control unit 7600. The passenger or the like inputs various types of data to the vehicle control system 7000 or gives instructions for processing operations by operating the input unit 7800.

[0141] The storage unit 7690 can include a read-only memory (ROM) that stores various types of programs executed by the microcomputer and a random access memory (RAM) that stores various parameters, operation results, sensor values, etc. In addition, the storage unit 7690 can be implemented by a magnetic storage device such as a hard disk drive (HDD), a semiconductor storage device, an optical storage device, or a magneto-optical storage device.

[0142] The general communication I / F 7620 is a widely used communication I / F that regulates communication with various devices existing in the external environment 7750. The general communication I / F 7620 can implement cellular communication protocols such as the Global System for Mobile Communications (GSM (registered trademark)), Worldwide Interoperability for Microwave Access (WiMAX (registered trademark)), Long Term Evolution (LTE (registered trademark)), or Advanced LTE (LTE-A), or other wireless communication protocols such as Wireless LAN (also known as Wireless Fidelity Wi-Fi (registered trademark)), Bluetooth (registered trademark), etc. The general communication I / F 7620 can be connected to a device (such as an application server or a control server) existing on an external network (such as the Internet, a cloud network, or a company private network) via a base station or an access point, for example. Additionally, for example, the general communication I / F 7620 can use peer-to-peer (P2P) technology to connect to a terminal that appears near the vehicle (the terminal is, for example, a driver's, a pedestrian's, or a store's terminal, or a machine type communication (MTC) terminal).

[0143] The dedicated communication I / F 7630 is a communication I / F that supports communication protocols developed for use in vehicles. For example, the dedicated communication I / F 7630 can implement standard protocols such as wireless access in vehicular environments (WAVE) (which is a combination of Institute of Electrical and Electronics Engineers (IEEE) 802.11p as the lower layer and IEEE 1609 as the upper layer), dedicated short range communication (DSRC), or cellular communication protocols. The dedicated communication I / F 7630 generally performs V2X communication, which is a concept including one or more of communication between vehicles (vehicle-to-vehicle), communication between a road and a vehicle (vehicle-to-infrastructure), communication between a vehicle and a home (vehicle-to-home), and communication between a pedestrian and a vehicle (vehicle-to-pedestrian).

[0144] For example, the positioning unit 7640 performs positioning by receiving Global Navigation Satellite System (GNSS) signals (e.g., GPS signals from Global Positioning System (GPS) satellites) from GNSS satellites, and generates position information including the latitude, longitude, and altitude of the vehicle. Incidentally, the positioning unit 7640 can identify the current position by exchanging signals with a wireless access point, or can obtain position information from a terminal such as a mobile phone, a Personal Handy-phone System (PHS), or a smart phone having a positioning function.

[0145] For example, the beacon receiving unit 7650 receives radio waves or electromagnetic waves transmitted from a radio station installed on a road or the like, thereby obtaining information such as the current position, congestion, closed roads, or required time. Incidentally, the function of the beacon receiving unit 7650 can be included in the above-mentioned dedicated communication I / F 7630.

[0146] The in-vehicle device I / F 7660 is a communication interface that mediates the connection between the microcomputer 7610 and various in-vehicle devices 7760 present in the vehicle. The in-vehicle device I / F 7660 can establish a wireless connection using wireless communication protocols such as Wireless LAN, Bluetooth (registered trademark), Near Field Communication (NFC), or Wireless Universal Serial Bus (WUSB). In addition, the in-vehicle device I / F 7660 can establish a wired connection via a connection terminal (and, if necessary, through a cable) not shown in the figure by Universal Serial Bus (USB), High-Definition Multimedia Interface (HDMI (registered trademark)), Mobile High-Definition Link (MHL), etc. For example, the in-vehicle device 7760 can include at least one of a mobile device and a wearable device owned by a passenger and an information device carried into the vehicle or attached to the vehicle. The in-vehicle device 7760 can also include a navigation device that searches for a route to an arbitrary destination. The in-vehicle device I / F 7660 exchanges control signals or data signals with these in-vehicle devices 7760.

[0147] The in-vehicle network I / F 7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The in-vehicle network I / F 7680 transmits and receives signals, etc. in accordance with a predetermined protocol supported by the communication network 7010.

[0148] Based on information obtained via at least one of the general communication I / F 7620, the dedicated communication I / F 7630, the positioning unit 7640, the beacon receiving unit 7650, the in-vehicle device I / F 7660, and the in-vehicle network I / F 7680, the microcomputer 7610 of the integrated control unit 7600 controls the vehicle control system 7000 according to various types of programs. For example, the microcomputer 7610 can calculate control target values for the driving force generating device, the steering mechanism, or the braking device based on the obtained information about the inside and outside of the vehicle, and output a control command to the drive system control unit 7100. For example, the microcomputer 7610 can perform cooperative control for functions aimed at implementing an advanced driver assistance system (ADAS), which includes vehicle collision avoidance or shock absorption, following driving based on the following distance, vehicle speed holding driving, vehicle collision warning, vehicle lane departure warning, etc. In addition, the microcomputer 7610 can perform cooperative control for autonomous driving by controlling the driving force generating device, the steering mechanism, the braking device, etc. based on the obtained information about the surroundings of the vehicle, enabling the vehicle to drive autonomously without relying on the driver's operation, etc.

[0149] Based on information obtained via at least one of the general communication I / F 7620, the dedicated communication I / F 7630, the positioning unit 7640, the beacon receiving unit 7650, the in-vehicle device I / F 7660, and the in-vehicle network I / F 7680, the microcomputer 7610 generates three-dimensional distance information between the vehicle and objects such as surrounding structures, people, etc., and generates local map information including peripheral information about the current position of the vehicle. In addition, the microcomputer 7610 can predict dangers such as the approach or entry of vehicle collisions, pedestrians, etc. into a closed road, etc. based on the obtained information, and generate a warning signal. For example, the warning signal can be a signal for generating a warning sound or lighting a warning lamp.

[0150] The sound / image output unit 7670 sends an output signal of at least one of sound and image to an output device capable of notifying information visually or auditorily to the passengers of the vehicle or to the outside of the vehicle. Figure 59In the example, as output devices, an audio speaker 7710, a display unit 7720, and a dashboard 7730 are shown. For example, the display unit 7720 may include at least one of an in-vehicle display and a head-up display. The display unit 7720 may have an augmented reality (AR) display function. The output device may be other devices such as headphones, wearable devices such as glasses-type displays worn by passengers, projectors, lights, etc., in addition to these. In the case where the output device is a display device, the display device visually displays the results obtained by various types of processing executed by the microcomputer 7610 or the information received from other control units in various forms such as text, images, tables, charts, etc. In addition, in the case where the output device is an audio output device, the audio output device converts an audio signal composed of reproduced audio data, sound data, etc. into an analog signal and outputs the analog signal auditorily.

[0151] Incidentally, in Figure 59 the example shown, at least two control units connected to each other via the communication network 7010 may be integrated into one control unit. Alternatively, each individual control unit may include a plurality of control units. In addition, the vehicle control system 7000 may include other control units not shown in the figure. In addition, a part or all of the functions executed by one control unit in the above description may be assigned to another control unit. That is, as long as information is transmitted and received via the communication network 7010, any control unit can perform predetermined arithmetic processing. Similarly, a sensor or device connected to one of the control units may be connected to another control unit, and the plurality of control units may transmit and receive detection information to and from each other via the communication network 7010.

[0152] It should be noted that computer programs for implementing the respective functions of the ranging devices 1000 and 2000 described with reference to Figures 1 to 58 etc. can be installed on any control unit or the like. In addition, a computer-readable recording medium storing such a computer program can also be provided. For example, the recording medium is a magnetic disk, an optical disk, a magneto-optical disk, a flash memory, etc. In addition, for example, the above computer program can be distributed via a network without using a recording medium.

[0153] For example, the above vehicle control system 7000 can use any one of the ranging devices 1000 and 2000 described with reference to Figures 1 to 58 etc. as the light source steering unit of the LIDAR, which is an environmental sensor.

[0154] In addition, at least some components of the ranging devices 1000 and 2000 described with reference to Figures 1 to 58 etc. can be implemented in a module (for example, an integrated circuit module included in one bare chip) for the integrated control unit 7600 shown in Figure 59 or, with reference toFigures 1 to 58 The ranging devices 1000 and 2000 described above can be implemented by Figure 59 multiple control units of the vehicle control system 7000 shown in the figure.

[0155] Although the present invention has been described above with reference to the embodiments and their variations, the present technology is not limited to the above embodiments and the like, and can be modified in various ways. It should be noted that the effects described herein are merely illustrative. The effects of the present invention are not limited to the effects described herein. The present invention may have effects other than those described herein.

[0156] In addition, the present invention may have the following configurations. (1) A ranging device, comprising: A first component, which includes a first optical waveguide configured to transmit a chirp signal; A light source that generates light to be modulated by a modulator to generate the chirp signal; A second component, which includes a logic circuit for controlling the light source, wherein the first component and the second component are stacked; and A first conductor that forms at least a part of the electrical connection between the logic circuit and the light source, wherein the first conductor penetrates the first component at a position spaced apart from the light source in a first direction. (2) The ranging device according to (1), wherein the first conductor passes through the first component. (3) The ranging device according to one or more of (1) to (2), wherein the first conductor passes through at least a part of the second component. (4) The ranging device according to one or more of (1) to (3), wherein the second component includes a silicon layer and an interlayer insulating film. (5) The ranging device according to one or more of (1) to (4), wherein the first conductor passes through the interlayer insulating film to reach the silicon layer. (6) The ranging device according to one or more of (1) to (5), wherein the first conductor is electrically connected to the wiring of the interlayer insulating film. (7) The ranging device according to one or more of (1) to (6), wherein the wiring is located at the joint surface between the first component and the second component. (8) The ranging device according to one or more of (1) to (7), wherein the wiring is located between the first surface of the interlayer insulating film and the second surface of the interlayer insulating film opposite to the first surface. (9) The ranging device according to one or more of (1) to (8), further comprising: At least one second conductor that electrically connects the first conductor to the light source. (10) The ranging device according to one or more of (1) to (9), wherein the first component includes at least a part of the at least one second conductor. (11) The ranging device according to one or more of (1) to (10), wherein at least a part of the at least one second conductor extends along the first direction. (12) The ranging device according to one or more of (1) to (11), wherein the at least one second conductor includes conductive bumps. (13) The ranging device according to one or more of (1) to (12), further comprising: A third component that includes the light source, wherein the first component is located between the second component and the third component. (14) The ranging device according to one or more of (1) to (13), wherein the third component includes at least a part of the at least one second conductor. (15) The ranging device according to one or more of (1) to (14), wherein the first conductor passes through at least a part of the third component, the first component, and the second component. (16) A ranging device, comprising: A first component that includes a first silicon layer, the first silicon layer including a first optical waveguide configured to transmit an optical signal; A light source that generates light to be modulated by a modulator to generate the optical signal; A second component that includes a second silicon layer, the second silicon layer including a logic circuit that controls the light source, wherein the first component and the second component are stacked; and A first conductor that forms at least a part of the electrical connection between the logic circuit and the light source, wherein the first conductor penetrates the first component at a position spaced apart from the light source in a first direction. (17) The ranging device according to (16), wherein the light source is located between the first optical waveguide and the first conductor. (18) The ranging device according to (16) to (17), wherein the first component further includes: A beam splitter configured to separate the optical signal into a transmission signal and a reference signal; and A coupler and a detector circuit configured to output a beat signal based on the reference signal and a reflected signal. (19) The ranging device according to claims (16) to (18), wherein the logic circuit includes: A controller configured to output an electronic control signal for controlling the generation of the optical signal. (20) A ranging device, comprising: A first component including a first optical waveguide configured to transmit a chirp signal; A light source that generates light to be modulated by a modulator to generate the chirp signal; A second component including a logic circuit for controlling the light source, wherein the first component and the second component are stacked; A first conductor forming at least a part of the electrical connection between the logic circuit and the light source, wherein the first conductor penetrates the first component at a position spaced apart from the light source in a first direction; and At least one second conductor forming the remaining part of the electrical connection between the logic circuit and the light source, wherein at least a part of the at least one second conductor extends in the first direction. (B1) A ranging device, comprising: A semiconductor substrate including a light source that outputs an optical signal; A photon integration circuit substrate including a modulator, a first waveguide, a splitter, a second waveguide, and a signal generator disposed in a common silicon layer, the modulator generating a chirp signal by modulating the frequency of the optical signal, the first waveguide transmitting the chirp signal, the splitter dividing the chirp signal into a transmission signal and a reference signal, the second waveguide transmitting a return signal corresponding to a signal having a delayed phase with respect to the transmission signal, and the signal generator generating a beat signal based on the reference signal and the return signal; and A signal processing substrate including a converter, a signal processor, and a controller, the converter performing analog-to-digital conversion on the beat signal, the signal processor processing the beat signal digitally generated by the converter, and the controller controlling the light source, the modulator, and the signal generator, The photon integration circuit substrate and the semiconductor substrate are sequentially stacked on the signal processing substrate, and The semiconductor substrate and the signal processing substrate are electrically connected to each other through vias. (B2) The ranging device according to (1), further comprising a first wiring electrically connecting the light source and the controller, wherein The first wiring includes a first via and a second via as the vias, the first via is disposed in the semiconductor substrate, and the second via is disposed in the semiconductor substrate, the photon integration circuit substrate, and the signal processing substrate. (B3) The ranging device according to (1) or (2) further includes a first heat dissipation member electrically connected to the light source, wherein, the first heat dissipation member includes a third via hole and a first wiring layer, the third via hole is provided in the semiconductor substrate, and the first wiring layer is provided on the front surface of the semiconductor substrate. (B4) The ranging device according to any one of (1) to (3), wherein the photon integration circuit substrate includes a diffraction grating located at a position opposite to the light source, and the diffraction grating guides the optical signal output from the light source to the modulator. (B5) The ranging device according to any one of (1) to (4), wherein the photon integration circuit substrate includes a second heat dissipation member located at a position opposite to the light source. (B6) A ranging device includes: a light source chip that outputs an optical signal; a photon integration circuit substrate that includes a modulator, a first waveguide, a splitter, a second waveguide, and a signal generator provided in a common silicon layer, the modulator generates a chirp signal by modulating the frequency of the optical signal, the first waveguide transmits the chirp signal, the splitter divides the chirp signal into a transmission signal and a reference signal, the second waveguide transmits a return signal corresponding to a signal having a delayed phase with respect to the transmission signal, and the signal generator generates a beat signal based on the reference signal and the return signal; and a signal processing substrate that includes a converter, a signal processor, and a controller, the converter performs analog-to-digital conversion on the beat signal, the signal processor processes the beat signal digitally generated by the converter, and the controller controls the light source chip, the modulator, and the signal generator, the photon integration circuit substrate has a recess or a cutout portion for accommodating the light source chip, an end portion of the first waveguide is exposed on an inner surface of the recess or the cutout portion, the light source chip is mounted in the recess or the cutout portion such that the optical signal is incident on the end portion of the first waveguide exposed on the inner surface of the recess or the cutout portion, the photon integration circuit substrate is stacked on the signal processing substrate, and the light source chip and the signal processing substrate are electrically connected to each other through a via hole. (B7) The distance measuring device according to (6) further includes a first wiring that electrically connects the light source chip and the controller to each other, where The first wiring includes a first via as the via, and the first via is provided in the photon integration circuit substrate and the signal processing substrate. (B8) The distance measuring device according to (6) or (7), where The photon integration circuit substrate has a groove portion provided on the bottom surface of the recess or the cutout portion, and The groove portion is provided at least in a region of the bottom surface of the recess or the cutout portion that is located between the first waveguide and the light source chip in a plan view. (B9) The distance measuring device according to (6) or (7), where The signal processing substrate includes a silicon substrate and an interlayer insulating film. The silicon substrate is provided with the converter, the signal processor, and the controller, and the interlayer insulating film is provided on the silicon substrate. The photon integration circuit substrate and the signal processing substrate have a groove portion provided on the bottom surface of the recess or the cutout portion. The groove portion has a depth that penetrates the interlayer insulating film from the bottom surface of the recess or the cutout portion, and The groove portion is provided at least in a region of the bottom surface of the recess or the cutout portion that is located between the first waveguide and the light source chip in a plan view. (B10) The distance measuring device according to (8) further includes a resin member embedded in the recess or the cutout portion and the groove portion. (B11) The distance measuring device according to (9) further includes a resin member embedded in the recess or the cutout portion and the groove portion. (B12) The distance measuring device according to any one of (6) to (11), where the surface of the inner surface of the recess or the cutout portion where the optical signal enters is arranged to be obliquely opposed rather than directly opposed to the light emitting surface of the light source chip. (B13) The distance measuring device according to any one of (6) to (12) further includes an antireflection film covering the surface of the inner surface of the recess or the cutout portion where the optical signal enters. (B14) A distance measuring device, comprising: A light source chip that outputs an optical signal; A photon integration circuit substrate, which includes a modulator, a first waveguide, a splitter, a second waveguide, and a signal generator disposed in a common silicon layer. The modulator generates a chirp signal by modulating the frequency of the optical signal. The first waveguide transmits the chirp signal. The splitter divides the chirp signal into a transmission signal and a reference signal. The second waveguide transmits a return signal corresponding to a signal having a delayed phase relative to the transmission signal. The signal generator generates a beat signal based on the reference signal and the return signal; and A signal processing substrate, which includes a converter, a signal processor, and a controller. The converter performs analog-to-digital conversion on the beat signal. The signal processor processes the beat signal digitally generated by the converter. And the controller controls the light source chip, the modulator, and the signal generator, The photon integration circuit substrate has a recess or a cutout for accommodating the light source chip, An end portion of the first waveguide is exposed on an inner surface of the recess or the cutout, The light source chip is mounted in the recess or the cutout so that the optical signal is incident on the end portion of the first waveguide exposed on the inner surface of the recess or the cutout, The photon integration circuit substrate is stacked on the signal processing substrate, and The light source chip and the photon integration circuit substrate are electrically connected to each other by bonding copper pads to each other. The copper pads are provided between the signal processing substrate and the photon integration circuit substrate. (B15) The ranging device according to (14) further includes a second wiring for electrically connecting the light source chip and the controller. Wherein, The second wiring includes the copper pads and a connection wiring layer for electrically connecting the light source chip and the copper pads to each other.

[0157] Those skilled in the art should understand that various deformations, combinations, sub-combinations, and changes can be made according to design requirements and other factors as long as they are within the scope of the appended claims or their equivalents. List of reference numerals

[0158] 61 Si platform portion 62 p-type Si layer 63 Island-shaped i-type Ge layer 64 Two-dimensionally grown i-type Ge layer 65 n-type Ge layer 66 n-side electrode 67 p-side electrode 100 First bare chip 100A PIC substrate 101 Si layer 101a layer 102 interlayer insulating film 103 BOX layer 104 Si substrate 105 diffraction grating 106 SOI substrate 107 heat dissipation member 110 modulator 120 optical splitter 130 circulator 140 antenna 141 Si antenna 142 heater 143, 144, 145 optical switches 150 coupler 151, 152 optical waveguides 160 detector 161, 162 Ge-PD 163 transimpedance amplifier 200 second bare chip 201 semiconductor substrate 202 Si substrate 210 laser 211, 212 contact layers 220 lens 230 laser substrate 300 third bare chip 301 Si substrate 302 interlayer insulating film 303, 304, 305 pad electrodes 310 controller 320 DAC 330 ADC 340 FFT 410 wiring 411, 412 vias 413 wiring layer 420 wiring 421, 422 vias 423 wiring layer 430 wiring 431, 432 vias 433 wiring layer 440 heat dissipation member 441 via 442 wiring layer 500 first bare chip 500A PIC substrate 501 and 502 diffraction gratings 503 reflective layer 510 recess 510a side surface 511 notch 520 groove 530 resin member 540 and 550 via openings 561, 562, and 563 pad electrodes 571 and 572 bonding wires 580 support substrate 590 insulating film 591 and 592 recesses 593 and 594 protrusions 600 laser chip 601 active layer 602 waveguide 610 and 620 electrodes 630 protrusion 710 wiring 711 solder 712 via 713 wiring layer 720 wiring 721 solder 722 via 723 wiring layer 724 connecting wiring 1000 and 2000 distance measuring devices H1 to H6 via openings L laser S1 and S2 bonding surfaces S3 incident / output surface S4 bonding surface S5 incident / output surface Sbt beat signal Srx return signal Stx, Stx1, and Stx2 transmission signals TG target WG1, WG2, WG3, and WGa optical waveguides

Claims

1. A distance measuring device, comprising: A first component, which includes a first optical waveguide configured to transmit a chirp signal; A light source that generates light to be modulated by a modulator to generate the chirp signal; A second component, which includes a logic circuit for controlling the light source, wherein the first component and the second component are stacked; and A first conductor that forms at least a part of the electrical connection between the logic circuit and the light source, wherein the first conductor penetrates the first component at a position spaced apart from the light source in a first direction.

2. The distance measuring device according to claim 1, wherein the first conductor passes through the first component.

3. The distance measuring device according to claim 1, wherein the first conductor passes through at least a part of the second component.

4. The distance measuring device according to claim 3, wherein the second component includes a silicon layer and an interlayer insulating film.

5. The distance measuring device according to claim 4, wherein the first conductor passes through the interlayer insulating film to reach the silicon layer.

6. The distance measuring device according to claim 4, wherein the first conductor is electrically connected to the wiring of the interlayer insulating film.

7. The distance measuring device according to claim 6, wherein the wiring is located at the bonding surface between the first component and the second component.

8. The distance measuring device according to claim 6, wherein the wiring is located between the first surface of the interlayer insulating film and the second surface of the interlayer insulating film opposite to the first surface.

9. The distance measuring device according to claim 1, further comprising: At least one second conductor that electrically connects the first conductor to the light source.

10. The distance measuring device according to claim 9, wherein the first component includes at least a part of the at least one second conductor.

11. The distance measuring device according to claim 9, wherein at least a part of the at least one second conductor extends in the first direction.

12. The distance measuring device according to claim 9, wherein the at least one second conductor includes a conductive bump.

13. The distance measuring device according to claim 9, further comprising: A third component, which includes the light source, wherein the first component is located between the second component and the third component.

14. The distance measuring device according to claim 13, wherein the third component includes at least a part of the at least one second conductor.

15. The distance measuring device according to claim 13, wherein the first conductor passes through the third component and the first component, and through at least a part of the second component.

16. A distance measuring device, comprising: A first component, which includes a first silicon layer, and the first silicon layer includes a first optical waveguide configured to transmit an optical signal; A light source that generates light to be modulated by a modulator to generate the optical signal; A second component, which includes a second silicon layer, and the second silicon layer includes a logic circuit for controlling the light source, wherein the first component and the second component are stacked; And A first conductor that forms at least a part of an electrical connection between the logic circuit and the light source, wherein the first conductor penetrates the first component at a position spaced apart from the light source in a first direction.

17. The ranging device according to claim 16, wherein, The light source is located between the first optical waveguide and the first conductor.

18. The distance measuring device according to claim 16, wherein, The first component further includes: A splitter configured to separate the optical signal into a transmission signal and a reference signal; and A coupler and a detector circuit configured to output a beat signal based on the reference signal and the reflected signal.

19. The distance measuring device according to claim 18, wherein, The logic circuit includes: A controller configured to output an electronic control signal for controlling generation of the optical signal.

20. A distance measuring device, comprising: A first component including a first optical waveguide configured to transmit a chirp signal; A light source that generates light to be modulated by a modulator to generate the chirp signal; A second component including a logic circuit for controlling the light source, wherein the first component and the second component are stacked; A first conductor that forms at least a part of an electrical connection between the logic circuit and the light source, wherein the first conductor penetrates the first component at a position spaced apart from the light source in a first direction; and At least one second conductor that forms the remaining part of the electrical connection between the logic circuit and the light source, wherein at least a part of the at least one second conductor extends in the first direction.

Images