JP2004327584A - Optical interconnection circuit, method for manufacturing thereof and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical interconnection circuit which can perform light control introduced into an optical waveguide with high precision, enables easy miniaturization, and can be easily manufactured. <P>SOLUTION: The optical interconnection circuit is equipped with a surface light emitting laser 1 and a first light receiving element 5 constituted of minute tiling-like element formed on a substrate 10 and a first light receiving element, an optical waveguide 4 having optical waveguide material which is formed on the substrate 10 and optically coupled with a light emitting part 1a of the surface light emitting laser 1 and a light receiving part 5a of the first light receiving element 5, an integrated circuit chip 20 which is flip chip mounted on the substrate 10 and arranged so as to cover at least a part of the optical waveguide 4, and a photodiode 2 which is included by the integrated circuit chip 20 and formed at a position facing the optical waveguide 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical interconnection circuit, a method for manufacturing an optical interconnection circuit, an electro-optical device, and an electronic apparatus.
[0002]
[Prior art]
In recent years, as a flat display device, an electroluminescence display device, a plasma display device, a liquid crystal display device, and the like have been used. In these display devices, technologies for using optical signals for data transmission are being studied in order to eliminate signal delays and the like accompanying large-sized and large-capacity displays. In computers, the operating speed (operating clock) inside the CPU has been improving year by year due to the miniaturization of the internal structure of the integrated circuit, but the data transmission speed on the bus connecting the CPU and peripheral devices such as storage devices is almost limited. And is becoming a bottleneck in computer processing speed. If optical signals can be used for data transmission on this bus, the processing speed limit of the computer can be significantly increased.
[0003]
In order to transmit data using an optical signal, an optical transmission means for transmitting an optical signal emitted from a light emitting element to a predetermined location and inputting the signal to a light receiving element or the like is required. As such conventional optical transmission means, there is a technique using an optical fiber or a technique using an optical waveguide formed on a substrate (for example, Patent Document 1 below).
[0004]
[Patent Document 1]
JP-A-5-167060
[0005]
[Problems to be solved by the invention]
However, when an optical fiber is used as an optical transmission means, connection with optical components such as a light-emitting element and a light-receiving element becomes complicated, and it takes a lot of cost and time to manufacture the optical transmission means, and it is difficult to reduce the size of the optical transmission means. Problem.
[0006]
On the other hand, by using an optical waveguide formed on a substrate, it is conceivable to simplify the connection between an optical transmission medium and a light emitting element, a light receiving element, and the like. There is a demand for the establishment of an optical transmission means having an optical waveguide which has been miniaturized to a certain degree and which is easy to manufacture. In addition, in order to perform stable optical transmission, it is necessary to control the amount of light introduced into the optical waveguide irrespective of an aging change such as an external environment change or element deterioration. In particular, when a semiconductor laser is used as a light emitting element, since the laser efficiency of the semiconductor laser changes depending on the ambient temperature or the like, it is required to optically monitor and control the amount of light.
[0007]
The present invention has been made in view of the above circumstances, and is capable of accurately controlling the amount of light introduced into an optical waveguide, and can be easily miniaturized, and can be easily manufactured. It is an object to provide a method and an electronic device.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, an optical interconnection circuit according to the present invention includes a light-emitting element and a first light-receiving element each formed of a small tile-shaped element provided on a substrate, and the light-emitting element provided on the substrate. An optical waveguide having an optical waveguide material optically coupled to the light emitting section and the light receiving section of the first light receiving element; and a flip chip mounted on the substrate, and disposed so as to cover at least a part of the optical waveguide. And a second light receiving element included in the integrated circuit chip and provided at a position facing the optical waveguide.
According to the present invention, an optical signal emitted from a light emitting element composed of a small tile element can propagate through an optical waveguide to reach a first light receiving element that is another small tile element having a light receiving function, Optical signals can be transmitted and received between the micro tiled elements. Therefore, a very high-speed signal transmission means can be easily realized. In addition, the minute tile-shaped element is formed into a very small shape (for example, an element having an area of several hundred μm square or less and a thickness of several tens μm or less) to easily manufacture a very fine optical signal transmission means. can do. Here, as an optical waveguide material forming the optical waveguide, a transparent material such as a transparent resin or sol-gel glass can be applied. Sol-gel glass is obtained by transforming a solution containing a glass component into a solid glass by heating or the like.
A part of the light emitted from the light emitting element may leak from the optical waveguide, but the second light receiving element is provided at a position facing the optical waveguide, so that the second light receiving element leaks. Receives leaked light. Therefore, the second light receiving element can monitor the light amount of the light propagating through the optical waveguide based on the light receiving signal based on the leaked light, and thus the output (light emission amount) of the light emitting element. Then, by adjusting the output of the light emitting element based on the monitoring result, the amount of light introduced into the optical waveguide can be controlled.
Further, according to the present invention, since the integrated circuit chip including the second light receiving element is flip-chip mounted on the substrate via bumps or the like which are conductive members, a clearance is provided between the integrated circuit chip and the substrate. Is formed. Therefore, by providing an optical waveguide and a light emitting element in the clearance, contact between the integrated circuit chip including the second light receiving element and the optical waveguide and the light emitting element can be avoided, and damage to the light receiving element, the light emitting element, or the optical waveguide can be prevented. Can be prevented.
Further, according to the present invention, as described above, an optical waveguide and a light emitting element can be arranged in the clearance, and the light emitting element is formed as a small tile-shaped element, so that the output of the light emitting element can be monitored. The circuit can be made extremely compact, and the semiconductor integrated circuit can be easily manufactured using existing manufacturing techniques.
Here, the micro tile element may be a compound semiconductor or a silicon semiconductor, and the substrate to which the micro tile element is bonded may be a silicon semiconductor substrate or a compound semiconductor substrate. Therefore, a hybrid substrate (a semiconductor integrated circuit capable of monitoring the output of a surface emitting laser with high accuracy) in which a compound semiconductor and a silicon semiconductor are three-dimensionally combined, which cannot be formed by a single monolithic substrate, is extremely compact. Can be formed.
[0009]
Here, the second light receiving element only needs to face a part of the optical waveguide so as to be able to receive the leaked light, and does not need to be arranged at a position facing the light emitting element (near the light emitting element). Good.
[0010]
On the other hand, the integrated circuit chip is disposed so as to cover the light emitting element, and the second light receiving element is provided at a position facing the light emitting element. The output can be monitored more accurately. In addition, since the integrated circuit chip is disposed so as to cover the light emitting element, external disturbance light incident on the second light receiving element can be blocked by the integrated circuit chip, and the output of the light emitting element can be more precisely. Can be monitored.
[0011]
In the optical interconnection circuit according to the present invention, the integrated circuit chip includes an automatic output control circuit that controls the amount of light emitted from the light emitting element based on the amount of light received by the second light receiving element.
According to the present invention, by providing the automatic output control circuit that controls the light emission amount of the light emitting element based on the light reception amount of the second light receiving element, without being affected by temperature change, aging, manufacturing quality, etc. A compact semiconductor integrated circuit that stably outputs a desired amount of emitted light for many years can be provided at low cost. The automatic output control circuit may be provided on a substrate.
[0012]
Here, when the amount of light emitted from the light emitting element and the amount of leaked light leaking from the optical waveguide are in a proportional relationship, the automatic output control circuit calculates the amount of light received from the second light receiving element based on the result of proportional calculation. The amount of light emitted from the light emitting element can be controlled. On the other hand, for example, the distance condition between the light emitting position of the light emitting element and the leak position of the leak light (the leak light detecting position of the second light receiving element), and the light transmission characteristics of the optical waveguide (light transmission loss characteristics, waveguide loss characteristics). If the amount of light emitted from the light emitting element and the amount of leaked light leaking from the optical waveguide are not in a proportional relationship due to the detection condition, the amount of light emitted from the light emitting element and the amount of leaked light leaking from the optical waveguide are not determined. The relationship may be derived in advance based on the detection condition, and the automatic output control circuit may control the light emission amount of the light emitting element based on the derived result.
[0013]
In the optical interconnection circuit according to the aspect of the invention, the optical waveguide has a leakage portion that leaks a part of light from the light emitting element to the outside, and the second light receiving element receives the leaked light. And
According to the present invention, by providing a leak portion for partially leaking light propagating through the optical waveguide in a part of the optical waveguide, the light amount of the light propagating through the optical waveguide, and thus the output of the light emitting element, Can be accurately monitored. That is, when the optical waveguide material forming the optical waveguide is a transparent material as described above, part of the light propagating through the optical waveguide leaks naturally, but does not leak naturally when it is an opaque material. The case is conceivable. Therefore, even when such an opaque material is used, the amount of light emitted from the light-emitting element can be monitored accurately by providing the leakage portion.
[0014]
In this case, it is possible to include a light reflecting film provided on a surface of an optical waveguide material forming the optical waveguide, and the leakage portion can have an opening formed in a part of the light reflecting film. It is. Thus, a part of the light propagating through the optical waveguide leaks outside through the opening and can enter the second light receiving element. Further, by providing the reflective film, it is possible to suppress light leakage from portions other than the leakage portion (opening), and thus it is possible to suppress the waveguide loss (transmission loss) of the optical waveguide and obtain good light transmission efficiency. it can.
[0015]
When the optical waveguide is made of the transparent material (transparent resin or sol-gel glass), for example, the leakage part has a different reflectance (refractive index) from the area where the leakage part is to be formed in the optical waveguide to other areas. The region may be processed as described above. For example, a light scattering portion is formed by mixing light scattering particles in a material constituting a region where a leakage portion is to be formed of an optical waveguide, providing a light scattering member, or forming an uneven shape by embossing or the like. May be used as the leakage part. Further, the material of the region where the leakage portion is to be formed can be made of a material different from the material of the other region.
[0016]
In this case, it is preferable that the leaking part is provided near the light emitting element in the optical waveguide. Thus, the second light receiving element can accurately monitor the output of the light emitting element by receiving the light leaked from the leak portion provided near the light emitting element.
[0017]
Further, in this case, it is preferable that the leaking part is arranged on the light emitting axis of the light emitting element, and accordingly, the light receiving part of the second light receiving element is also arranged on the light emitting axis of the light emitting element. It is preferred that Thereby, the output of the light emitting element can be monitored more accurately.
[0018]
In the optical interconnection circuit according to the present invention, the optical waveguide is formed in a planar or linear shape along a plane of the substrate.
According to the present invention, for example, a plane or line is formed between a first micro tile element having a light emitting function (light emitting element) and a second micro tile element having a light receiving function (first light receiving element). The optical signal propagates through the optical waveguide material by being connected by the optical waveguide material provided in the shape, and the optical signal can be transmitted between the first micro tile element and the second micro tile element. it can. Further, for example, by providing an optical waveguide material in a planar or linear shape so as to cover one first micro tile element having a light emitting function and a plurality of second micro tile elements having a light receiving function. Optical signals output from one first micro tiled element can be received simultaneously by a plurality of second tiled elements, and higher-speed signal transmission can be performed. On the other hand, by providing an optical waveguide material in a planar or linear shape so as to cover a plurality of first micro tile elements having a light emitting function and a plurality of second micro tile elements having a light receiving function, High-speed signal transmission can be performed between the first micro tile element and the plurality of second micro tile elements. Here, by setting the wavelength of the light of the optical signal to be output to each of the first minute tile-shaped elements to be different, it is possible to easily configure the bus using the optical signal.
[0019]
In the optical interconnection circuit according to the present invention, the light emitting element is a surface emitting laser.
According to the present invention, a minute light emitting element can be provided by using a surface emitting laser as the light emitting element. Here, since the surface emitting laser is made of a compound semiconductor, it is very difficult to directly form a silicon integrated circuit by a semiconductor process such as epitaxy without lattice matching with silicon. Therefore, a surface emitting laser is formed once on a gallium arsenide substrate, and then the surface emitting laser is formed by chipping into a minute tile shape. By forming such a chip, the surface emitting laser can be disposed at an arbitrary position on a substrate such as silicon.
[0020]
In the optical interconnection circuit according to the present invention, the light receiving element is a photodiode.
According to the present invention, a semiconductor integrated circuit having a combination of a surface emitting laser and a photodiode, which cannot be formed by a single monolithic substrate, can be formed extremely compactly and easily.
[0021]
The method of manufacturing an optical interconnection circuit according to the present invention includes the steps of: adhering a light emitting element composed of a micro tile element and a first light receiving element on a substrate; and a light emitting section of the light emitting element and the first light receiving element on the substrate. Providing an optical waveguide including an optical waveguide material optically coupled to a light receiving portion of the light receiving element; and providing an integrated circuit chip including a second light receiving element on the substrate so as to cover at least a part of the optical waveguide. Flip-chip mounting.
ADVANTAGE OF THE INVENTION According to this invention, the optical interconnection circuit which can monitor the output of the light emitting element which consists of a micro tile-shaped element with high precision can be easily manufactured using the existing manufacturing technique. Further, according to the present invention, the optical interconnection circuit can be easily made compact.
[0022]
Here, the method includes a step of forming a light reflection film having an opening in a part of the surface of the optical waveguide material forming the light waveguide, wherein the light reflection film includes the light reflection film forming material. A structure in which droplets of a liquid material are ejected can be employed. This makes it possible to easily form a leak portion that leaks a part of light propagating through the optical waveguide at a desired position based on the droplet discharge method while suppressing waste of material consumption.
[0023]
According to another aspect of the invention, an electronic apparatus includes the above-described optical interconnection circuit.
According to the present invention, it is possible to provide an inexpensive electronic device including a compact optical interconnection circuit that can stably introduce an optical signal having a desired light emission amount into an optical waveguide for many years. For example, by applying the optical interconnection circuit of the present invention to an integrated circuit, high-speed signal processing and compact electronic equipment can be provided at low cost. Further, according to the present invention, it is possible to provide an electric device capable of displaying a high-quality image by applying an optical interconnection circuit to a display device, for example.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an optical interconnection circuit of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view showing one embodiment of the optical interconnection circuit of the present invention.
In FIG. 1, the optical interconnection circuit includes a light emitting element 1 and a first light receiving element 5 each composed of a micro tile-shaped element provided on a substrate 10, and a light emitting unit 1a of the light emitting element 1 provided on the substrate 10. An optical waveguide 4 having an optical waveguide material optically coupled to the light receiving portion 5a of the first light receiving element 5; and an integrated circuit mounted on the substrate 10 by flip-chip and arranged to cover at least a part of the optical waveguide 4 A circuit chip 20 and a second light receiving element 2 included in the integrated circuit chip 20 and provided at a position facing the optical waveguide 4 are provided. In the present embodiment, the light emitting element 1 is a surface emitting laser, and the second light receiving element 2 is a photodiode. The surface emitting laser (light emitting element) 1 is attached to the surface (upper surface) of the substrate 10. The first light receiving element 5 is also a photodiode, and the photodiode (first light receiving element) 5 is also attached to the surface (upper surface) of the substrate 10.
[0025]
The minute tile-shaped element including the surface emitting laser 1 and the photodiode 5 is a semiconductor device having a minute tile shape (plate shape), for example, a thickness of several tens μm or less and an area of several hundred μm. ² The following rectangular plate-like members are shown. A method for manufacturing the micro tile element will be described later. Note that the shape of the minute tile-shaped element including the surface emitting laser 1 is not limited to a square, and may be another shape.
[0026]
As the substrate 10, any material such as glass, plastic, glass epoxy substrate, ceramic, semiconductor substrate, and silicon can be used. The integrated circuit chip 20 is flip-chip mounted on the substrate 10 via bonding pads (not shown) provided at desired positions on the substrate 10 and bumps 21 made of a conductive member. The circuit in the integrated circuit chip 20 is electrically connected to wiring (not shown) provided on the substrate 10 via the bump 21 and the bonding pad. The wiring of the substrate 10 is electrically connected to the surface emitting laser 1. Therefore, the surface emitting laser 1 is electrically connected to a circuit in the integrated circuit chip 20 via the bumps 21 and the like.
[0027]
In the present embodiment, the integrated circuit chip 20 is disposed so as to cover the surface emitting laser 1 on the substrate 10. The integrated circuit chip 20 includes an APC (Auto Power) for controlling the light emitting amount (output) of the surface emitting laser 1 based on the photodiode 2 as the second light receiving element and the detection value (light receiving amount) of the photodiode 2. (Control) driver circuit (automatic output control circuit) 3. The photodiode 2 is arranged so as to face the upper surface of the surface emitting laser 1. Here, the light receiving section of the photodiode 2 is preferably arranged on the light emitting axis of the surface emitting laser 1.
[0028]
FIG. 2 is a plan view of FIG. 1 and particularly shows the optical waveguide 4. The optical waveguide 4 is made of an optical waveguide material such as a transparent resin or sol-gel glass, and is formed linearly on the surface of the substrate 10. One end of the optical waveguide 4 covers the light emitting section 1a of the surface emitting laser (first micro tile element) 1, and the other end thereof is a first light receiving element (second micro tile element). 5 is covered. The first light receiving element 5 is attached to the surface of the substrate 10, and the optical waveguide material forming the optical waveguide 4 includes at least the light emitting section 1 a of the surface emitting laser 1 and the light receiving section 5 a of the first light receiving element 5. It is formed on the surface of the substrate 10 so as to cover it.
When the substrate 10 is made of silicon, a photodiode can be directly formed as the first light receiving element 5 on the substrate 10 made of silicon. Alternatively, the first light receiving element 5 for receiving an optical signal may be provided on an integrated circuit chip 20 provided at a position facing the light emitting element 1. In this case, the first light receiving element 5 for receiving an optical signal is disposed on the light emitting axis of the light emitting element 1, while the photodiode 2, which is the second light receiving element for monitoring the amount of light, It is arranged at a position shifted from the light emitting axis and capable of receiving the leaked light from the optical waveguide 4.
[0029]
With such a configuration, light emitted from the light emitting unit 1a of the surface emitting laser 1 as the first micro tile element propagates through the optical waveguide 4, and the first light receiving element as the second micro tile element. 5 reaches the light receiving section 5a. Therefore, when the light emitting operation of the light emitting unit 1a is controlled to emit an optical signal from the light emitting unit 1a, the optical signal propagates through the optical waveguide 4, and the optical signal transmitted through the optical waveguide 4 is detected by the light receiving unit 5a. Can be.
[0030]
In addition, an optical signal emitted from the surface emitting laser 1 propagates through the optical waveguide 4 to enter the first light receiving element 5 and pass over the first light receiving element 5. Thus, an optical signal can be transmitted from one surface emitting laser 1 to a plurality of light emitting elements 5 substantially simultaneously. Here, by setting the thickness of the first light emitting element 5 to 20 μm or less, the step with the substrate becomes sufficiently small, so that the optical waveguide 4 can be continuously formed over the step as shown in FIG. Even if the optical waveguide 4 is continuously formed at the step portion, light transmission loss such as scattering can be almost ignored because the step is small. Therefore, a special structure or an optical element for reducing the step is not required in the step. Therefore, it can be easily manufactured at low cost. Further, the thickness of the optical waveguide material forming the optical waveguide 4 can be reduced to several tens μm or less.
[0031]
On the other hand, part of the light emitted from the surface emitting laser 1 becomes leaked light that leaks to the outside after propagating upward through the optical waveguide 4 as shown in FIG. The photodiode 2 provided on the integrated circuit chip 20 receives the leaked light.
[0032]
Next, output control of the surface emitting laser 1 by the APC driver circuit 3 will be described with reference to FIG. First, most of the light emitted from the surface emitting laser 1 propagates in the optical waveguide 4 in the longitudinal direction as an optical signal L1. On the other hand, the leaked light L2 leaked to the outside of the optical waveguide 4 enters the photodiode 2 as the second light receiving element. Here, the light quantity of the light signal L1 emitted from the surface emitting laser 1 and the light quantity of the leak light (monitor light) L2 are in a proportional relationship. That is, when the light amount of the optical signal L1 decreases, the light amount of the leakage light L2 also decreases in proportion thereto.
[0033]
Since the leak light L2 is incident on the photodiode 2, a current corresponding to the amount of the leak light L2 flows through the photodiode 2. The APC driver circuit 3 converts the value of the current flowing through the photodiode 2 into a detection signal as a detection value, and compares the detection value with a predetermined reference value. Further, the APC driver circuit 3 controls the drive voltage or drive current of the surface emitting laser 1 so that the comparison result becomes a constant value. As a result, the light emission amount (optical signal L1 and leakage light L2) of the surface emitting laser 1 is feedback-controlled, and is maintained at a desired value for many years without being affected by ambient temperature, aging, and the like.
[0034]
The APC driver circuit 3 may be provided on the substrate 10 instead of being provided on the integrated circuit chip 20. Further, the APC driver circuit 3 may be configured to be separated into an APC circuit section and a driver circuit section. Further, the APC circuit section may be configured to be separated into a detection circuit (including a preamplifier) for detecting the output of the photodiode 2 and an APC circuit.
[0035]
As described above, according to the present embodiment, the optical signal emitted from the surface emitting laser 1 can propagate through the optical waveguide 4 and reach the first light receiving element 5 for receiving the optical signal. Can transmit and receive optical signals. Therefore, a very high-speed signal transmission means can be easily realized. Further, by forming the element in a very small shape, a very fine optical signal transmission means can be easily manufactured. Then, of the light emitted from the surface emitting laser 1, the leakage light leaking from the optical waveguide 4 made of a transparent material is converted into a photodiode which is a second light receiving element for light amount monitoring provided at a position facing the optical waveguide 4. By receiving the light at 2, the photodiode 2 can monitor the amount of light propagating through the optical waveguide 4 based on the light receiving signal related to the leaked light, and thus the output (light emission amount) of the surface emitting laser 1. Therefore, the output of the surface emitting laser 1 can be adjusted based on the monitoring result, and the amount of light introduced into the optical waveguide 4 can be controlled.
[0036]
Since the integrated circuit chip 20 including the photodiode 2 is flip-chip mounted on the substrate 10, a clearance is formed between the integrated circuit chip 20 and the substrate 10. Therefore, by providing the optical waveguide 4 and the surface emitting laser 1 in this clearance, contact between the integrated circuit chip 20 including the photodiode 2 and the optical waveguide 4 and the surface emitting laser 1 can be avoided. 1 or the optical waveguide 4 can be prevented from being damaged. Since the optical waveguide 4 and the surface emitting laser 1 are arranged in the clearance between the substrate 10 and the integrated circuit 20, and the surface emitting laser 1 is formed as a small tile-shaped element, the output of the surface emitting laser 1 can be monitored. The semiconductor integrated circuit can be made extremely compact, and the semiconductor integrated circuit can be easily manufactured using existing manufacturing techniques.
[0037]
4A and 4B are diagrams showing another embodiment of the optical waveguide 4, FIG. 4A is a side sectional view, and FIG. 4B is a plan view. A light reflecting film 6 having an opening 6a at a predetermined position is provided on the surface of the optical waveguide material forming the optical waveguide 4. That is, the light reflecting film 6 is provided on the entire surface of the optical waveguide material except the opening 6a. This light reflection film 6 is made of a metal film. Examples of a material for forming the metal film (light reflection film) 6 include gold, silver, aluminum, magnesium, copper, nickel, titanium, chromium, and zinc.
[0038]
In the present embodiment, the metal film 6 is formed based on a droplet discharge method. The droplet discharge method is a method of forming a film pattern on a predetermined surface by discharging liquid material droplets from a discharge nozzle of a droplet discharge head onto a predetermined surface. In the present embodiment, the metal film 6 is formed by discharging and arranging a droplet of a liquid material in which metal fine particles are dispersed in a dispersion medium on the surface of the optical waveguide material. This makes it possible to easily form the metal film 6 having the opening 6a at a desired position while suppressing waste of material consumption. When a liquid material droplet is placed on the surface of the optical waveguide material, it is preferable that the surface of the optical waveguide material is previously subjected to a surface treatment for controlling the liquid repellency (or lyophilicity).
[0039]
The opening 6a serves as a leaking part for leaking a part of the light propagating through the optical waveguide 4, and the photodiode 2 provided in the integrated circuit chip 20 leaks through the opening 6a. The light L2 is received. Here, the opening (leakage portion) 6 a is preferably provided near the photodiode 2 on the surface of the optical waveguide material forming the optical waveguide 4, and is further disposed on the light emitting axis of the surface emitting laser 1. Is preferred.
[0040]
As described above, the provision of the leak portion 6a that actively leaks a part of the light emitted from the surface emitting laser 1 to the outside enables the photodiode 2 to monitor the leak light satisfactorily. Further, by providing the reflection film 6 on the entire surface of the optical waveguide material other than the opening (leakage portion) 6a as in the present embodiment, it is possible to suppress light leakage from portions other than the leakage portion 6a. No. 4 can obtain good light transmission efficiency.
[0041]
It is sufficient that the leakage portion has a larger amount of light leakage than the other region. For example, the region where the leakage portion is to be formed is formed of a different material from the other region, or the light reflectance (refractive index) is different from that of the other region. The leaking portion may be formed by a process of making the leaking portion different, for example, by mixing light scattering particles in a region where the leaking portion is to be formed, by providing a light scattering member, or by embossing or the like to form an uneven shape.
[0042]
In each of the above embodiments, the light emitting element 1 may include, for example, an LED or a DFB (Distributed Feedback) laser in addition to the VCSEL (surface emitting laser). As a light emitting device, an LED has the simplest structure and is easy to manufacture, but the modulation speed of an optical signal is as slow as several hundred Mbps. On the other hand, VCSELs can perform very high-speed modulation exceeding 10 Gbps, and can be driven with low power consumption because the threshold current is small and the luminous efficiency is high. The DFB laser emits laser light in a direction parallel to the plane of the substrate 10, that is, along the optical waveguide 4, from the edge of the minute tile shape, although the modulation speed is about 1 Gbps, which is inferior to a surface emitting laser. The optical signal can be transmitted more efficiently than the surface emitting laser. It should be noted that the DFB laser may have a built-in electro-absorption modulator. In this way, a modulation speed exceeding 10 Gbps can be obtained, so that it is possible to achieve both efficient optical signal propagation of the DFB and high-speed modulation.
[0043]
The second light receiving element 2 and the first light receiving element 5 may include, for example, a phototransistor in addition to a photodiode. Here, as the photodiode, a PIN photodiode, an APD (avalanche photodiode), and an MSM (Metal-Semiconductor-Metal) photodiode can be selected according to the application. APD has high light sensitivity and high response frequency. The MSM photodiode has a simple structure and is easily integrated with an amplifying transistor.
Note that light receiving elements having different characteristics between the first light receiving element 5 and the second light receiving element 2 can be used. For example, since the second light receiving element 2 is used for monitoring the amount of light, the linearity (linearity) between the amount of incident light and the output signal is important, but the high-speed response is allowed to some extent because the time average of the amount of light is measured. . On the other hand, the first light receiving element 5 is for receiving an optical signal, so that high-speed response is important. On the other hand, the received optical signal is an ON / OFF pulse signal, so that the linearity is allowed to some extent. Devices used as the first and second light receiving elements are appropriately selected based on such a viewpoint.
[0044]
The surface emitting laser 1 and the first light receiving element 5 are electrically connected to an integrated circuit provided on the substrate 10 or an electronic circuit (not shown) such as an EL display circuit, a plasma display, and a liquid crystal display circuit. ing. As a result, a computer system including an integrated circuit and the like can be made faster than before, while being compact. In addition, a scanning signal from a flat display provided on the substrate 10 can be transmitted at high speed by the optical interconnection circuit of the present embodiment, and the screen size and quality of the flat display device can be increased. it can.
[0045]
In FIG. 1, the surface emitting laser 1 and the first light receiving element 5 are respectively connected to one light guide path 4 one by one, but the number of the first light receiving elements 5 is plural. Is also good. In this case, an optical signal transmitted from one surface emitting laser 1 propagates through one light guide path 4 and is simultaneously detected by a plurality of first light receiving elements 5. This is the same as a one-to-many bus line. Further, each of the surface emitting laser 1 and the first light receiving element 5 may be plural. Here, each of the surface emitting lasers 1 may emit a different wavelength of light. Further, it is preferable that each first light receiving element 5 is a light receiving means having a wavelength selecting function corresponding to a wavelength of light emitted by at least one surface emitting laser 1. Thus, a plurality of optical signals respectively transmitted from the plurality of surface emitting lasers 1 can be simultaneously propagated through one optical waveguide 4 and detected by each of the plurality of first light receiving elements 5. Therefore, a bus that can transmit and receive a plurality of optical signals in parallel can be easily configured.
[0046]
Although the optical waveguide 4 is formed in a straight line in FIG. 1, it may be formed in a curved line or branched into a plurality. Further, it may be formed in a loop shape. Further, it may be formed in a sheet shape (plane shape) so as to cover a plurality of tile elements. Needless to say, a plurality of sets of the surface emitting laser 1, the first light receiving element 5, and the optical waveguide 30 may be formed on the surface of one substrate 10. Furthermore, the surface emitting laser 1, the light receiving element, and the optical waveguide 4 can be formed on both the front and back surfaces of the substrate 10.
[0047]
The photodiode 2 may be provided with a filter that transmits only light having a desired wavelength (for example, the emission wavelength of the surface emitting laser 1). In this case, since the light incident on the photodiode 2 is only the light emitted from the surface emitting laser 1, the light emission amount of the surface emitting laser 1 can be detected with high accuracy without being affected by disturbance light. it can.
[0048]
The integrated circuit chip 20 may include a conversion circuit that converts a parallel signal into a serial signal. In this case, the parallel signal output from the CPU or the like is converted into a serial signal in the integrated circuit chip 20 and the surface emitting laser 1 is driven by the serial signal, so that the serial signal related to the optical signal can be included. it can.
[0049]
<Method of manufacturing optical waveguide>
Next, a method of manufacturing the optical waveguide 4 in the optical interconnection circuit according to the above embodiment will be described with reference to FIGS. FIG. 5 is a schematic side view showing a method for manufacturing the optical waveguide 4.
[0050]
First, the first minute tile-shaped element (surface emitting laser) and the second minute tile-shaped element (first light receiving element) are adhered to the upper surface of the substrate 10. After that, the manufacturing process of the optical waveguide 4 is started. Then, as shown in FIG. 5A, the entire surface of the upper surface of the substrate 10 and the upper surfaces of the first micro-tile-shaped element and the second micro-tile-shaped element (not shown) is coated with a liquid photocurable resin 4c. . This coating is performed by a spin coating method, a roll coating method, a spray coating method, or the like.
[0051]
Next, the liquid photocurable resin 4c is irradiated with ultraviolet rays (UV) through a mask having a desired pattern. Thereby, only the desired region in the liquid photo-curable resin 4c is cured and patterned. Then, by removing the uncured resin by washing or the like, an optical waveguide 4d made of a cured optical waveguide material is formed as shown in FIG. 5B.
[0052]
FIG. 6 is a schematic side view showing another example of the method for manufacturing the optical waveguide 4. First, the first micro tile element and the second micro tile element are bonded to the upper surface of the substrate 10. After that, the manufacturing process of the optical waveguide 4 is started. Then, as shown in FIG. 6A, the upper surface of the substrate 10 and the entire upper surfaces of the first micro tile element and the second micro tile element (not shown) are coated with the resin 4e and cured. This coating is performed by a spin coating method, a roll coating method, a spray coating method, or the like. Next, a resist mask 41 is formed in a desired region of the resin 4e. The region where the resist mask 41 is formed is the same as the region where the optical waveguide 4 is formed.
[0053]
Next, as shown in FIG. 6B, the entire substrate 10 is subjected to dry etching or wet etching from above the resist mask 41 to remove the resin 4e other than under the resist mask 41. By performing photolithography patterning and removing the resist mask 41 in this manner, an optical waveguide 4f made of an optical waveguide material is formed. Basically, it is based on the epitaxial lift-off method.
[0054]
FIG. 7 is a schematic side view showing another example of the method for manufacturing the optical waveguide 4. First, the first micro tile element and the second micro tile element are bonded to the upper surface of the substrate 10. After that, the manufacturing process of the optical waveguide 4 is started. Then, a liquid-repellent surface 51 is provided by performing liquid-repellent treatment on the upper surface of the substrate 10 and the entire upper surfaces of the first microtile-shaped elements and the second microtile-shaped elements (not shown).
[0055]
Next, as shown in FIG. 7A, a desired pattern area on the liquid-repellent surface 51 is irradiated with ultraviolet rays or the like to form a lyophilic surface 52 having a desired pattern in the liquid-repellent surface 51. Next, as shown in FIG. 7B, 4 g of a liquid optical waveguide material is dropped onto the lyophilic surface 52 from an ink jet nozzle or a dispenser. As the optical waveguide material 4g, a transparent resin or sol-gel glass is used. Then, by curing the optical waveguide material 4g dropped on the substrate 10, the optical waveguide 4h made of the optical waveguide material is formed. When the optical waveguide 4g is formed of sol-gel glass, a solution or the like obtained by adding an acid to a metal alkoxide and hydrolyzing the solution is dropped onto the lyophilic surface 52 from an inkjet nozzle or a dispenser. Next, energy such as heat is applied to the dropped solution to vitrify it, thereby obtaining an optical waveguide 4h.
[0056]
FIG. 8 is a schematic side view showing another example of the method for manufacturing the optical waveguide 4. First, the first micro tile element and the second micro tile element are bonded to the upper surface of the substrate 10. After that, the manufacturing process of the optical waveguide 4 is started. Then, as shown in FIG. 8A, the upper surface of the substrate 10 and the upper surfaces of the first and second minute tile-shaped elements are covered with the region where the optical waveguide 4 is to be provided. Then, a liquid resin 4i is applied.
[0057]
Next, a stamper 51 having a pattern shape 52 of the optical waveguide 30 is pressed from above the substrate 10 onto the surface of the substrate 10. Next, as shown in FIG. 8B, the stamper 51 is lifted from the surface of the substrate 10. Thus, an optical waveguide 4j made of an optical waveguide material having a desired pattern shape is formed on the substrate 10 by a pattern transfer method using the stamper 51.
[0058]
As a method of manufacturing the optical waveguide 4, a method described below may be used in addition to the method shown in FIGS. For example, an optical waveguide material forming the optical waveguide 4 may be provided by using a printing method such as screen printing or offset printing. Further, an optical waveguide material forming the optical waveguide 4 may be provided by using a slit coating method of discharging a liquid resin from the slit-shaped gap. As the slit coating method, a method of applying a desired member such as a resin to the substrate 10 using a capillary phenomenon may be employed.
[0059]
<Manufacturing method of micro tile element>
Next, a method of manufacturing the minute tile-shaped element forming the surface emitting laser 1 and a method of bonding the minute tile-shaped element to a substrate (final substrate) will be described with reference to FIGS. In the present manufacturing method, a case in which a compound semiconductor device (compound semiconductor device) as a minute tile-shaped element is bonded onto a silicon / LSI chip serving as a final substrate will be described. The present invention can be applied. The “semiconductor substrate” in the present embodiment refers to an object made of a semiconductor material, but is not limited to a plate-shaped substrate, and any shape of semiconductor material is included in the “semiconductor substrate”. . In the method for manufacturing the micro tile element, the epitaxial lift-off method is used as a basis.
[0060]
(First step)
FIG. 9 is a schematic sectional view showing a first step of the method of manufacturing the semiconductor integrated circuit. In FIG. 9, a substrate 110 is a semiconductor substrate, for example, a gallium-arsenic compound semiconductor substrate. A sacrificial layer 111 is provided on the lowest layer of the substrate 110. The sacrificial layer 111 is made of aluminum arsenic (AlAs) and has a thickness of, for example, several hundred nm. For example, a functional layer 112 is provided above the sacrificial layer 111. The thickness of the functional layer 112 is, for example, about 1 μm to 10 (20) μm. Then, a semiconductor device (surface emitting laser 1) 113 is formed in the functional layer 112. As the semiconductor device 113, for example, in addition to a surface emitting laser (VCSEL), other functional elements, for example, a driver circuit or an APC circuit including a high electron mobility transistor (HEMT), a hetero bipolar transistor (HBT), and the like are formed. Is also good. In each of these semiconductor devices 113, an element is formed by laminating a multilayer epitaxial layer on a substrate 110. Further, an electrode is formed on each semiconductor device 113, and an operation test is also performed.
[0061]
(2nd process)
FIG. 10 is a schematic sectional view showing a second step of the method for manufacturing a semiconductor integrated circuit. In this step, an isolation groove 121 is formed so as to divide each semiconductor device 113. The separation groove 121 is a groove having a depth that reaches at least the sacrifice layer 111. For example, both the width and the depth of the separation groove are set to 10 μm to several hundred μm. In addition, the separation groove 121 is a groove that is connected without a dead end so that a selective etching solution to be described later flows through the separation groove 121. Further, it is preferable that the separation grooves 121 are formed in a lattice shape like a go board. Further, by setting the interval between the separation grooves 121 to several tens μm to several hundred μm, the size of each semiconductor device 113 divided and formed by the separation grooves 121 has an area of several tens μm to several hundred μm square. Shall be. As a method for forming the separation groove 121, a method using photolithography and wet etching, or a method using dry etching is used. Further, the separation groove 121 may be formed by dicing a U-shaped groove to the extent that cracks do not occur in the substrate.
[0062]
(3rd step)
FIG. 11 is a schematic sectional view showing a third step of the method of manufacturing the semiconductor integrated circuit. In this step, the intermediate transfer film 131 is attached to the surface of the substrate 110 (on the semiconductor device 113 side). The intermediate transfer film 131 is a flexible film having a surface coated with an adhesive.
[0063]
(4th process)
FIG. 12 is a schematic sectional view showing a fourth step of the method for manufacturing the semiconductor integrated circuit. In this step, the selective etching solution 141 is injected into the separation groove 121. In this step, in order to selectively etch only the sacrificial layer 111, low concentration hydrochloric acid having high selectivity to aluminum and arsenic is used as the selective etching solution 141.
[0064]
(Fifth step)
FIG. 13 is a schematic sectional view showing a fifth step of the method for manufacturing a semiconductor integrated circuit. In this step, after injecting the selective etching solution 141 into the separation groove 121 in the fourth step, the entire sacrificial layer 111 is selectively etched and removed from the substrate 110 after a predetermined time has elapsed.
[0065]
(Sixth step)
FIG. 14 is a schematic sectional view showing a sixth step of the method for manufacturing a semiconductor integrated circuit. When the sacrificial layer 111 is entirely etched in the fifth step, the functional layer 112 is separated from the substrate 110. Then, in this step, by separating the intermediate transfer film 131 from the substrate 110, the functional layer 112 attached to the intermediate transfer film 131 is separated from the substrate 110. As a result, the functional layer 112 on which the semiconductor device 113 is formed is divided by forming the separation groove 121 and etching the sacrificial layer 111 to form a semiconductor element having a predetermined shape (for example, a minute tile shape) (“ The surface emitting laser 1) is attached and held on the intermediate transfer film 131. Here, it is preferable that the thickness of the functional layer is, for example, about 1 μm to 10 μm, and the size (length and width) is, for example, several tens μm to several hundred μm.
[0066]
(Seventh step)
FIG. 15 is a schematic sectional view showing a seventh step of the method for manufacturing a semiconductor integrated circuit. In this step, by moving the intermediate transfer film 131 (to which the minute tile-shaped element 161 is attached), the minute tile-shaped element 161 (the surface emitting laser 1) is moved to a desired position on the final substrate 171 (the transparent substrate 10). A) Align. Here, the final substrate 171 is made of, for example, a silicon semiconductor, and has an LSI region 172 formed therein. In addition, an adhesive 173 for bonding the micro tile element 161 is applied to a desired position of the final substrate 171. The adhesive may be applied to the minute tile-shaped element.
[0067]
(Eighth step)
FIG. 16 is a schematic sectional view showing an eighth step of the method for manufacturing a semiconductor integrated circuit. In this step, the minute tile-shaped element 161 aligned at a desired position on the final substrate 171 is pressed by the backing jig 181 over the intermediate transfer film 131 and joined to the final substrate 171. Here, since the adhesive 173 is applied to the desired position, the micro tile element 161 is bonded to the desired position on the final substrate 171.
[0068]
(Ninth step)
FIG. 17 is a schematic sectional view showing a ninth step of the method for manufacturing a semiconductor integrated circuit. In this step, the adhesive force of the intermediate transfer film 131 is eliminated, and the intermediate transfer film 131 is peeled off from the minute tile-shaped element 161. The adhesive of the intermediate transfer film 131 is UV-curable or thermosetting. In the case of using a UV curable adhesive, the back pressing jig 181 is made of a transparent material, and the adhesive force of the intermediate transfer film 131 is lost by irradiating ultraviolet rays (UV) from the tip of the back pressing jig 181. Let it. When a thermosetting adhesive is used, the back pressing jig 181 may be heated. Alternatively, after the sixth step, the adhesive force may be completely eliminated by irradiating the intermediate transfer film 131 with ultraviolet light over the entire surface. Although the adhesive force has disappeared, the adhesiveness actually remains slightly, and the micro tile element 161 is held on the intermediate transfer film 131 because it is very thin and light.
[0069]
(Tenth step)
This step is not shown. In this step, the minute tile element 161 is fully bonded to the final substrate 171 by performing a heat treatment or the like.
[0070]
(Eleventh process)
FIG. 18 is a schematic sectional view showing an eleventh step of the method for manufacturing a semiconductor integrated circuit. In this step, the electrodes of the minute tile-shaped element 161 (surface emitting laser 1) and the circuit on the final substrate 171 (transparent substrate 10) are electrically connected by wiring 191 to complete a semiconductor integrated circuit such as one LSI chip. Let it. As the final substrate 171, not only a silicon semiconductor but also a glass substrate, a quartz substrate, or a plastic film may be used.
[0071]
Thus, even if the transparent substrate 10 as the final substrate 171 is made of plastic, for example, the surface emitting laser 1 made of gallium / arsenic is formed at a desired position on the transparent substrate 10. The semiconductor element can be formed over a substrate made of a different material from the semiconductor element. Further, since the surface emitting laser 1 is completed on the semiconductor substrate and then cut into a minute tile shape, it is possible to test and sort the surface emitting laser 1 in advance before forming a semiconductor integrated circuit.
[0072]
Further, according to the above manufacturing method, only the functional layer including the semiconductor element (the surface emitting laser 1) can be cut out from the semiconductor substrate as a minute tile-shaped element and mounted on a film for handling. Can be individually selected and bonded to the transparent substrate 10, and the size of the surface emitting laser 1 that can be handled can be made smaller than that of the conventional mounting technology. Therefore, a compact semiconductor integrated circuit that outputs a desired amount of light and a desired state of laser light can be provided easily and at low cost.
[0073]
Then, after a surface emitting laser composed of micro tile elements formed by the process described with reference to FIGS. 9 to 18 is adhered on the substrate, the surface emitting laser is adhered to the substrate by the process described with reference to FIGS. An optical waveguide including an optical waveguide material that is optically coupled to a light emitting portion of a light emitting element is provided. Then, an integrated circuit chip 20 including a photodiode 2 is flipped on a substrate so as to cover the surface emitting laser 1 (optical waveguide 4). By mounting on a chip, the optical interconnection circuit shown in FIG. 1 is manufactured.
[0074]
<Electronic equipment>
An example of an electronic device including the optical interconnection circuit of the above embodiment will be described. FIG. 19 is a perspective view illustrating a configuration of a mobile personal computer (information processing device) including the display device according to the above-described embodiment. In the figure, a personal computer 1100 includes a main body 1104 having a keyboard 1102, and the above-described display device unit 1106.
[0075]
Since the electronic apparatus shown in FIG. 19 includes the optical interconnection circuit of the above embodiment, a compact optical interconnection circuit capable of stably introducing an optical signal of a desired light emission amount into an optical waveguide for many years is included in the electronic apparatus. Electronic equipment can be provided at low cost. For example, by applying the optical interconnection circuit of the present invention to an integrated circuit, high-speed signal processing and compact electronic equipment can be provided at low cost. Further, according to the present invention, it is possible to provide an electric device capable of displaying a high-quality image by applying an optical interconnection circuit to a display device, for example.
[0076]
In addition to the above-described example, as other examples, a mobile phone, a wristwatch type electronic device, a liquid crystal television, a viewfinder type or a monitor direct-view type video tape recorder, a car navigation device, a pager, an electronic notebook, a calculator, a word processor, Examples include a workstation, a videophone, a POS terminal, electronic paper, and a device equipped with a touch panel. The electro-optical device according to the invention can be applied to a display unit of such an electronic apparatus. Note that the electronic device of the present embodiment may be a device having a liquid crystal device, or an electronic device having another electro-optical device, such as an organic electroluminescence display device or a plasma display device.
[0077]
As described above, the preferred embodiments of the present invention have been described with reference to the accompanying drawings. However, it goes without saying that the present invention is not limited to the embodiments. The shapes, combinations, and the like of the constituent members shown in the above-described examples are merely examples, and can be variously changed based on design requirements and the like without departing from the gist of the present invention.
[Brief description of the drawings]
FIG. 1 is a schematic side sectional view showing one embodiment of an optical interconnection circuit of the present invention.
FIG. 2 is a plan view showing a main part including an optical waveguide.
FIG. 3 is an explanatory diagram illustrating an operation of the automatic output control circuit according to the embodiment.
FIG. 4 is a diagram showing another embodiment of the optical interconnection circuit of the present invention, showing a main part including an optical waveguide.
FIG. 5 is an explanatory view illustrating an example of a method for manufacturing an optical waveguide.
FIG. 6 is an explanatory view showing another example of a method for manufacturing an optical waveguide.
FIG. 7 is an explanatory view showing another example of a method for manufacturing an optical waveguide.
FIG. 8 is an explanatory view showing another example of a method for manufacturing an optical waveguide.
FIG. 9 is a schematic cross-sectional view showing a first step of the method for manufacturing a micro tile element.
FIG. 10 is a schematic cross-sectional view showing a second step of the manufacturing method.
FIG. 11 is a schematic cross-sectional view showing a third step of the above manufacturing method.
FIG. 12 is a schematic sectional view showing a fourth step of the manufacturing method according to the embodiment.
FIG. 13 is a schematic cross-sectional view showing a fifth step of the above manufacturing method.
FIG. 14 is a schematic cross-sectional view showing a sixth step of the above manufacturing method.
FIG. 15 is a schematic sectional view showing a seventh step of the above manufacturing method.
FIG. 16 is a schematic sectional view showing an eighth step of the above manufacturing method.
FIG. 17 is a schematic sectional view showing a ninth step of the above manufacturing method.
FIG. 18 is a schematic sectional view showing an eleventh step of the manufacturing method.
FIG. 19 illustrates an example of an electronic device of the invention.
[Explanation of symbols]
1. Surface emitting laser (light emitting element), 1a Light emitting unit,
2. Photodiode (second light receiving element),
3: APC driver circuit (automatic output control circuit), 4: optical waveguide,
5 ... first light receiving element, 5a ... light receiving section, 6 ... light reflection film,
6a: opening (leakage), 10: substrate, 20: integrated circuit chip,
21: bump, L1: optical signal, L2: leaked light

Claims (13)

A light emitting element and a first light receiving element, each of which is composed of a small tile-shaped element provided on a substrate,
An optical waveguide provided on the substrate and having an optical waveguide material optically coupled to a light emitting unit of the light emitting element and a light receiving unit of the first light receiving element;
An integrated circuit chip that is flip-chip mounted on the substrate and arranged to cover at least a part of the optical waveguide,
An optical interconnection circuit comprising: a second light receiving element included in the integrated circuit chip and provided at a position facing the optical waveguide. 2. The optical interconnection circuit according to claim 1, wherein the integrated circuit chip is disposed so as to cover the light emitting element, and the second light receiving element is provided at a position facing the light emitting element. 3. The optical interconnection according to claim 1, wherein the integrated circuit chip has an automatic output control circuit that controls an amount of light emitted from the light emitting element based on an amount of light received by the second light receiving element. circuit. The light guide according to any one of claims 1 to 3, wherein the optical waveguide has a leak portion that leaks a part of light from the light emitting element to the outside, and the second light receiving element receives the leaked light. The optical interconnection circuit according to claim 1. 5. The optical waveguide according to claim 4, further comprising a light reflecting film provided on a surface of an optical waveguide material forming the optical waveguide, wherein the leaking portion has an opening formed in a part of the light reflecting film. Optical interconnection circuit. The optical interconnection circuit according to claim 4, wherein the leakage portion is provided near the light emitting element in the optical waveguide. The optical interconnection circuit according to any one of claims 4 to 6, wherein the leakage part is arranged on a light emitting axis of the light emitting element. The optical interconnection circuit according to any one of claims 1 to 7, wherein a light receiving section of the second light receiving element is arranged on a light emitting axis of the light emitting element. The optical interconnection circuit according to any one of claims 1 to 8, wherein the optical waveguide is formed in a planar shape or a linear shape along a plane of the substrate. The optical interconnection circuit according to claim 1, wherein the light emitting element is a surface emitting laser. The optical interconnection circuit according to claim 1, wherein the second light receiving element is a photodiode. Adhering a light emitting element and a first light receiving element each composed of a micro tile element on a substrate;
Providing an optical waveguide including an optical waveguide material optically coupled to the light emitting unit of the light emitting element and the light receiving unit of the first light receiving element on the substrate;
Flip-chip mounting an integrated circuit chip including a second light receiving element on the substrate so as to cover at least a part of the optical waveguide. An electronic device comprising the optical interconnection circuit according to claim 1.

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