JP2008102318A - Optical element, optical integrated device and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical element including a molded body molded by utilizing an impact solidification phenomenon, and to provide an optical integrated device equipped with the same. <P>SOLUTION: The optical element comprises a lower electrode formed on a substrate, a waveguide which is comprises a molded body, molded by applying mechanical impact force to an ultrafine particulate brittle material supplied to the substrate to join the ultrafine particulate brittle material and which is formed on the lower electrode, and an upper electrode formed on the waveguide, wherein the lower electrode is constituted of a metal multilayer film. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical element used for optical communication, optical wiring, optical storage, and an optical integrated device in which it is integrated.

The electro-optic effect in which the refractive index changes due to the interaction between an electric field and a substance is applied to an optical modulator because of its high speed, low power consumption due to voltage drive, and simplicity of structure. In an optical modulator using LiNbO ₃ , a Mach-Zehnder type waveguide is formed on a single crystal LiNbO ₃ substrate by a Ti diffusion method, and an optical modulator is formed by combining electrodes. By applying a voltage, the refractive index of the waveguide can be changed, and the optical signal can be turned ON / OFF. However, since it is necessary to use a single crystal substrate, it is expensive, and since the electro-optic effect of LiNbO ₃ is small and the planar electrode structure is required, the length of the waveguide is required, and the element size is in the cm range. There is a disadvantage that it is very large.

Pb _1-x La _x (Zr _y Ti _1-y ) _{1-x / 4} O ₃ (hereinafter referred to as PLZT), which is a transparent ceramic, is two times higher than the LiNbO ₃ single crystal used in current optical modulators. Since the electro-optic coefficient is almost as large as possible, it can be expected to reduce cost, reduce power consumption, and increase the speed by reducing the size of the optical element. 1 and Non-Patent Document 2).

  However, in order to form a thin film with a high light transmittance and a large electro-optic effect, it is necessary to perform epitaxial growth, and since a single crystal substrate is required as a base material, it is formed on another substrate such as a silicon-based waveguide. However, there is a drawback that a long film forming process is required to form a film thickness required for the optical element by the sol-gel method, which is expensive.

Electro-optical materials such as LiNbO ₃ and PLZT are all ferroelectric materials, and their characteristics are manifested when a crystal structure unique to each compound is formed. For this reason, in order to use the electro-optic material as an optical element, it has been considered essential to use its own single crystal substrate or to epitaxially grow the electro-optic material on the single crystal substrate.

  In the future, the realization of nanophotonic devices that enable integration of electro-optic elements and electronic elements on one chip is required as a major innovation. In order to realize this, it is necessary to have technology for forming LSIs such as CPU and memory and active optical elements such as optical switches on the same substrate. Electro-optical materials such as PLZT are highly crystallized on a silicon or quartz substrate. Therefore, there is a need for a technique for film formation. As a technique for forming an electro-optic element on a different substrate, a technique for directly joining a thinned bulk electro-optic material is known, and a single layer or a multilayer is used to ensure the waveguide characteristics of the electro-optic element. It has been reported that an intermediate layer having a structure is provided (see Patent Document 1).

  On the other hand, as a new oxide film formation technique, aerosol deposition (AD method) utilizing a normal temperature impact solidification phenomenon has been developed. The AD method utilizes the impact adhesion phenomenon of ultrafine particle materials. Realization of a high film formation rate and a low process temperature is expected compared to conventional thin film formation methods (see Non-Patent Document 3). In addition, since the AD method does not depend on the underlying layer, the substrate can be freely selected.

  Patent Document 2 discloses a method for forming a brittle material ultrafine particle compact. In this molding method, the ultrafine particle brittle material supplied onto the substrate is subjected to mechanical impact and pulverized, and the ultrafine particle brittle materials or the ultrafine particle brittle materials and the ultrafine particle brittle material and the substrate are joined. It is characterized by. This realizes bonding between the ultrafine particles, and a high-density and high-strength film is formed without applying heat.

  Patent Document 3 discloses that a structure formed by the AD method is concerned. This structure is a polycrystalline body having no crystal orientation, and is substantially free of a grain boundary layer composed of a glass layer. It is a feature.

  On the other hand, in Non-Patent Document 4, studies on thin film forming of electro-optical material with high transparency using the AD method are made. According to this, it has been clarified that the transmission loss of the AD film, which is a basic characteristic of the optical element, is due to Rayleigh scattering of fine particles forming a compact and non-molded fine particles having different refractive indexes.

Furthermore, Patent Document 4 discloses an optical element, an optical integrated device, an optical information propagation system, and a method for manufacturing a molded body by AD method. For example, regarding an optical element, an optical element in which a compact is formed by an impact solidification phenomenon in which a mechanical impact force is applied to an ultrafine particle brittle material supplied on a substrate to pulverize and bond the ultrafine particle brittle material. , The average radius d (nm) of the portion where the refractive index of pores (holes), different phases, etc. contained in the optical element is different from the main constituent of the molded body and the wavelength λ (nm) of the light propagating through the molded body There is a relationship of d ⁶ / λ ⁴ <4 × 10 ⁻⁵ (nm ² ) between the optical elements. Furthermore, the optical element is formed by a lower electrode formed on the substrate and an impact solidification phenomenon in which a mechanical impact force is applied to the ultrafine particle brittle material on the lower electrode to pulverize and bond the ultrafine particle brittle material. A structure comprising a waveguide made of a molded body and an upper electrode formed on the waveguide is disclosed.

JP 2004-145261 A Japanese Patent Laid-Open No. 2001-3180 JP 2002-235181 A JP 2005-181995 A "Comparison of electro-optic lead-lanthanum zircinate titanate films on crystalline and glass substrates" K. D. Preston and G. H. Haertling: Appl. Phys. Let. Vol. 60 June 1992. “Patterning of (Pb, La) (Zr, Ti) O3 waveguides for fabricating micro-optics using wetting and solid-phase epitaxy” K. Nashimoto, K. Haga, M. Watmura and M. Watanabe, Phys. Lett. Vol.75, No.8, 23 August 1999, p1054. “Microstructure and Electrical Properties of Lead Zirconate Titanate (Pb (Zr52 / Ti48) O3) Thick Films Deposited by Aero J Depot. “Optical and electro-optical properties of Pb (Zr, Ti) O3 and (Pb, La) (Zr, Ti) O3 films prepared by aerosol deposition method” Masafumi Nakada, Keishi Oh Joun ) e1275.

  By applying an electro-optic material film by the AD method to an optical element such as an optical modulator, a waveguide made of an electro-optic material is formed on an arbitrary lower electrode because the material characteristics do not depend on the substrate or the base material. can do. Accordingly, a structure in which the waveguide is sandwiched between the lower and upper electrodes is possible, an electric field can be effectively applied to the waveguide, and the optical element can be downsized or reduced in power consumption. As these electrode materials, it is desirable to use a metal material having a small electric resistance because it enables high-speed operation of the optical element.

  However, when an electro-optic material film is formed on the lower electrode made of a metal material such as gold by the AD method, since the ultrafine particle brittle material collides with the lower electrode at a high speed, the lower electrode is deformed by its mechanical impact force. Or I found the problem of destroying.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical element in which a molded body by an AD method is formed on a lower electrode made of a metal material having a low electrical resistance.

  Another object of the present invention is to provide an optical integrated device using an optical element made of a molded body by the AD method, and a manufacturing method thereof.

  An optical element according to the present invention comprises a lower electrode formed on a substrate and a molded body formed by joining the ultrafine particle brittle material by applying a mechanical impact force to the ultrafine particle brittle material supplied to the substrate. It includes a waveguide formed on the lower electrode and an upper electrode formed on the waveguide, and the lower electrode is made of a metal multilayer film. When the lower electrode is made of a metal multilayer film, the hardness of the metal film can be increased, and a molded body can be formed on the lower electrode with increased hardness.

  In the optical element, it is preferable that the metal multilayer film includes a plurality of layers containing at least one of gold, silver, copper, Ir, Ru, W, and Mo as a main component and another metal layer. A metal multilayer film composed of a plurality of layers mainly composed of at least one of gold, silver, copper, Ir, Ru, W, and Mo having a low electrical resistance is higher in hardness than a single layer film and has a lower electrode. Therefore, it is suitable for the lower electrode of the optical element.

  In the optical element, it is preferable that each of the plurality of layers has a thickness of 500 nm or less. In order to increase the hardness of the lower electrode, it is necessary to stack an initial growth layer having a small crystal grain size. If the thickness of each of the plurality of layers is 500 nm or less, the hardness can be increased by stacking.

  In the optical element, the optical element is an optical modulator or an optical switch that controls light by applying an electric signal to an electrode. According to the present invention, it is possible to form an optical modulator and an optical switch that can respond at high speed and can be reduced in size or power consumption by adopting a structure in which a molded body is sandwiched between a lower electrode and an upper electrode.

  According to the present invention, a first optical element including a molded body formed by applying a mechanical impact force to an ultrafine particle brittle material supplied to a substrate and bonding the ultrafine particle brittle material, and a second optical element Each of which is integrated on the substrate, wherein the first optical element includes a lower electrode formed on the substrate and the molded body formed on the lower electrode. And an upper electrode formed on the waveguide, wherein the lower electrode is made of a metal multilayer film. In this optical integrated device, the second optical element is any one of a laser, an electric-optical converter, an optical-electric converter, an optical amplifier, an optical switch, and an optical filter. In this case, integration of a plurality of optical elements, which has been difficult due to different manufacturing processes, can be achieved by forming an impact solidification phenomenon that can be formed on any underlying material at room temperature.

  According to the present invention, an optical element including a molded body formed by bonding a mechanical impact force to an ultrafine particle brittle material supplied to a substrate and bonding the ultrafine particle brittle material, and an electronic circuit are further provided. An optical integrated device integrated on the substrate, wherein the optical element includes a lower electrode formed on the substrate, a waveguide made of the molded body formed on the lower electrode, and the waveguide. And an upper electrode formed on the waveguide, wherein the lower electrode is made of a metal multilayer film. In this optical integrated device, the electronic circuit is a central processing unit or a memory. In this case, integration of optical elements and electronic circuits on the same substrate, which was difficult due to different manufacturing processes, can be achieved by forming an impact solidification phenomenon that can be formed on any underlying material at room temperature. Become.

  In the optical element and the optical integrated device according to the present invention, an active element such as an optical modulator and a device can be manufactured by using an electro-optical material as a constituent material of the molded body.

  In the optical element and the optical integrated device according to the present invention, the electro-optic material is mainly composed of lead zirconate titanate to which lead zirconate titanate or lanthanum is added. Active elements such as modulators and devices can be manufactured.

  The manufacturing method of the optical element and the integrated optical device according to the present invention is characterized in that the manufacturing method of the molded body is molding by a normal temperature impact solidification phenomenon. By using the normal temperature impact solidification phenomenon, a molded body can be formed on an arbitrary substrate at room temperature. Among the film forming methods based on the normal temperature impact solidification phenomenon, the aerosol deposition method is suitable as a method for producing a molded body.

  According to the present invention, it becomes possible to form on a low electrical resistance electrode a molding by room temperature impact solidification phenomenon, that is, a super compact brittle material is bonded by applying a mechanical impact force to the ultra fine brittle material, Thereby, a high-performance optical element and an optical integrated device can be provided.

  Before describing the embodiments of the present invention, the progress of the present invention will be described. In the present invention, when an oxide electro-optic material is formed on a lower electrode made of a metal material by an AD method using a normal temperature impact solidification phenomenon, it is necessary to increase the hardness of the metal film. This is based on the finding that it is effective to multilayer the metal layer with other metal layers.

  Hereinafter, it demonstrates using a figure. FIG. 6 shows a cross-sectional structure of an optical modulator in which a lead zirconate titanate (PZT) film, which is an electro-optic material, is formed on a metal lower electrode by an AD method, and an upper electrode is formed thereon. The lower electrode is made of gold. In the AD method, an AD film is formed by colliding PZT particles on the lower electrode at a high speed, but it is clear from experiments that the lower electrode is deformed or broken by the mechanical impact force. became. FIG. 7 is an SEM photograph showing a cross section of the sample. The corrugated structure observed in the middle part is a lower electrode made of gold, and it can be seen that the flat gold thin film is greatly deformed by the collision of particles. When the lower electrode is deformed in this way, the light incident on the PZT is scattered, so that it cannot be used as an optical element.

  Further, in order for the PZT film formed by the AD method to exhibit the electro-optic effect, annealing at about 600 ° C. is necessary. FIG. 8 is a photomicrograph after annealing of the PZT film formed on the lower electrode by the AD method, and a large number of circular peeling portions are observed. Such peeling is caused by concentration of thermal stress during annealing on the electrode deformed portion.

  The present inventors have found that it is effective to make the low electrical resistance layer of the lower electrode multi-layered in order to prevent the destruction of the laminated structure caused by the film formation by the AD method.

  FIG. 1 schematically shows a cross-sectional structure of an optical modulator according to the present invention. It is characterized in that the gold layer of the lower electrode has two layers. FIG. 3 is a photomicrograph after annealing of the PZT film formed by AD method on the lower electrode composed of two gold layers. There was no peeling or cracking, and good optical properties were exhibited.

  The effect of the multi-layered low electrical resistance layer in the lower electrode is considered as follows. Increasing the hardness of the metal layer is effective in preventing the deformation of the lower electrode due to the collision of PZT particles. In order to prevent deformation of the metal crystal grain, the crystal grain boundary which is an interface between the crystal grains can increase the hardness of the thin film by inserting a large number of crystal grain boundaries in the film. In the growth of thin films such as sputtering, crystal nuclei are first formed, and the film grows around the nuclei. For this reason, at the initial stage of film formation, the crystal grains are small, a large number of crystal grain boundaries exist, and a film with high hardness can be obtained. On the other hand, since it is necessary to reduce the electrical resistance in order to use it as an electrode, a thin initial formation layer having a high electrical resistance cannot be used for the electrode layer. Therefore, by laminating the initial film formation state in which the crystal grains do not increase, the hardness of the film can be increased and the low electrical resistance can be satisfied.

  As described above, for the first time, it has been clarified by the present invention that an optical element having an AD film formed thereon can be formed by multilayering a lower electrode made of a metal film. By applying this result, high-performance optical elements and optical integrated devices can be formed at low cost.

  Hereinafter, the present invention will be described in detail with reference to some examples.

(First embodiment)
FIG. 1 is a diagram schematically showing a cross-sectional structure of an optical element according to the present invention. A lower electrode 42 was formed on a glass substrate (Corning 7059) 41 by sputtering. The lower electrode 42 includes a Ti layer (film thickness 3 nm) 43, a gold layer (film thickness 200 nm) 44, a Ti layer (film thickness 5 nm) 45, a gold layer (film thickness 200 nm) 46, and a Ti layer (film thickness 3 nm) 47. It is a metal multilayer film. A DC magnetron sputtering method was used for the sputtering method, and Ar gas was used as the sputtering gas. An electro-optic layer 48 was formed on the lower electrode 42 by the AD method. The film forming method will be described in detail later. Subsequently, after annealing in the atmosphere at 600 ° C. for 30 minutes, surface polishing was performed, and an upper electrode 49 was formed on the polished electro-optic layer 48 by a sputtering method. The upper electrode 49 is composed of a Ti layer (film thickness 3 nm) 410 and a gold layer (film thickness 200 nm) 411, and the film formation method is the same as that of the lower electrode 42.

  Next, the film forming method by the AD method used in the first embodiment will be described in detail. FIG. 2 is a schematic view of a film forming apparatus used in the present invention. A gas cylinder 61 containing oxygen gas is connected to the glass bottle 62 through a transfer tube. A raw material powder 63 made of an ultrafine particle brittle material is placed in a glass bottle 62 and evacuated to a vacuum of about 20 Torr through an exhaust pipe 64, and then oxygen is introduced as a carrier gas while controlling its flow rate. The glass bottle 62 is vibrated by the vibrator 65 to generate an aerosol in which fine particles of the raw material powder are dispersed in a gas, and the carrier gas is transported to the film forming chamber 67 through the transport pipe 66. The film forming chamber 67 is evacuated to a predetermined degree of vacuum by a vacuum pump 68. By spraying the raw material powder onto the substrate 610 in the film forming chamber 67 from the nozzle 69, a thin film is formed.

The film forming conditions are as follows. The carrier gas is oxygen, the incident angle with respect to the substrate 610 is 30 degrees, the gas flow rate is 12 (l / min), the film forming speed is 0.5 μm / min, and the vibration frequency of the vibrator 65 is 200 rpm. Glass was used for the substrate 610. As a raw material powder as a film forming material, lead zirconate titanate (PZT) based powder which is an oxide having a large electro-optic effect was used. The composition of PZT is x = 0.3 in Pb (Zr _x Ti _1-x ) O ₃ . The average particle size of the raw material powder was 0.7 μm. The film thickness is 3 μm. The PZT-based powder as a film forming material is a ferroelectric composition having a perovskite crystal structure, and is a composition that can be applied to an optical device having a first-order large electro-optic coefficient.

  FIG. 3 is a photomicrograph after annealing of the PZT film (electro-optic layer 48) by the AD method formed on the lower electrode 42 composed of two gold layers. As described above, there was no peeling, cracking, etc., and good optical properties were exhibited.

  Next, as a comparative example, the case of a single-layer lower electrode made of a low resistance metal such as gold will be described.

  FIG. 6 is a diagram schematically showing a cross-sectional structure of an optical modulator as a comparative example. On the glass substrate (Corning 7059) 11, the lower electrode 12 was formed by sputtering. The lower electrode includes a Ti layer (film thickness 3 nm) 13, a gold layer (film thickness 200 nm) 14, and a Ti layer (film thickness 3 nm) 15. A DC magnetron sputtering method was used for the sputtering method, and Ar gas was used as the sputtering gas. An electro-optic layer 16 was formed on the top by AD method. The method for forming the electro-optical layer 16 is the same as that in the first embodiment. Subsequently, after annealing in the atmosphere at 600 ° C. for 30 minutes, surface polishing was performed, and an upper electrode 17 was formed thereon by a sputtering method. The upper electrode 17 includes a Ti layer (film thickness 3 nm) 18 and a gold layer (film thickness 200 nm) 19, and the film formation method is the same as that of the lower electrode 12.

  FIG. 7 is an SEM photograph of a cross section of a sample manufactured as a comparative example. A lower electrode 22 made of gold is formed on the glass substrate 21, and an electro-optic layer 23 made of PZT by the AD method is formed on the lower electrode 22. As described above, the corrugated structure observed in the intermediate portion is the lower electrode 22 made of gold, and it can be seen that the flat gold thin film is greatly deformed by the collision of particles. When the lower electrode 22 is deformed in this way, the light incident on the PZT is scattered, so that it cannot be used as an optical element.

  FIG. 8 is a photomicrograph after annealing of the PZT film formed on the lower electrode 22 by the AD method, and a large number of circular peeling portions are observed as described above. These peeling portions are generated due to concentration of thermal stress during annealing on the deformed portion of the lower electrode 22.

  On the other hand, in the first embodiment, the lower electrode 42 is formed by multilayering the low electrical resistance layer, whereby an optical element having good optical characteristics can be obtained.

The first embodiment relates to PZT which is an electro-optic material, but the material system is not limited thereto, and lanthanum-added lead zirconate titanate, barium titanate, strontium-added barium titanate, KTN The same effect can be obtained by electro-optic materials such as SiO ₂ and optical waveguide forming materials such as SiO ₂ and silicon nitride. Further, the optical waveguide layer (electro-optic layer) does not need to be a single layer.

(Second embodiment)
A second embodiment of the present invention will be described with reference to FIGS. The second embodiment is an example in which the present invention is applied to a Fabry-Perot modulator.

FIG. 4 is a diagram schematically showing a cross-sectional structure of a Fabry-Perot optical modulator according to the present invention. A lower electrode 72 was formed on a glass substrate (Corning 7059) 71 by sputtering. The lower electrode 72 includes a Ti layer (film thickness 3 nm) 73, a gold layer (film thickness 200 nm) 74, a Ti layer (film thickness 5 nm) 75, a gold layer (film thickness 200 nm) 76, and a Ti layer (film thickness 3 nm) 77. It is a metal multilayer film. The film forming method is the same as in the first embodiment. An electro-optic layer 78 was formed on the top by AD method. The method for forming the electro-optic layer 78 is the same as that in the first embodiment. Subsequently, after annealing in the atmosphere at 600 ° C. for 30 minutes, the surface of the electro-optic layer 78 was polished, and a transparent electrode ITO (film thickness 120 nm) 79 was formed thereon by a sputtering method. A DC magnetron sputtering method was used for the sputtering method, and Ar gas was used as the sputtering gas. A dielectric multilayer film 710 was formed thereon by sputtering. The configuration of the dielectric multilayer film 710 is (SiO ₂ / Ta ₂ O ₅ ) 5 cycles (only 3 cycles are shown for convenience in FIG. 4), and Ar gas was formed as a sputtering gas by DC magnetron sputtering.

  FIG. 5 is a characteristic diagram showing the wavelength dependence of the reflectance. In FIG. 5, a reflectance spectrum 81 is in a state where no voltage is applied, and a reflectance peak due to Fabry-Perot interference is observed. The reflectance spectrum 82 is in a state where 120 V is applied, and the peak of transmittance due to Fabry-Perot interference is shifted to the high wavelength side, and it can be seen that the reflectance can be controlled by voltage.

  On the other hand, when the gold layer of the lower electrode was made a single layer, the AD film was peeled off during annealing, and the structure as shown in FIG. 4 could not be formed.

  Further, when the thickness of each gold layer of the lower electrode 72 exceeded 500 nm, there was no effect of multi-layering, and the AD film was peeled off or the optical characteristics were lowered during annealing.

  The advantage that the characteristics of the AD film do not essentially depend on the crystallinity of the underlayer is that, for example, other types of optical elements such as lasers, electrical-optical converters, optical-electrical converters, optical amplifiers, optical waveguides, optical filters, etc. The optical element according to the present invention is further formed on a substrate on which an integrated circuit composed of electronic elements such as a CPU (central processing unit) and a memory is formed in advance. As a whole, it can be applied to the production of an optical integrated device in which an optical device constituted by the optical element of the present invention and other devices are integrated.

  In the above embodiment, the case where one metal layer of the metal multilayer film constituting the lower electrode is gold has been described. However, not only gold but also gold, silver, copper, Ir, Ru, W, Mo It is good also as a layer which has at least 1 of these as a main component, and it is not necessary for all the layers to be the same metal. In the above embodiment, Ti is used as the other metal layer, but Cr, Ta, Nb, etc. may be used instead.

  An optical element, an optical integrated device, and a manufacturing method thereof according to the present invention form a molded body in which a mechanical impact force is applied to an ultrafine particle brittle material to join the ultrafine particle brittle material on a lower electrode with low electrical resistance. It can be applied to a wide range of objects.

FIG. 1 is a sectional view of an optical element structure using a two-layer lower electrode made of gold as a first embodiment of the present invention. FIG. 2 is a diagram schematically showing a configuration of a film forming apparatus by an aerosol deposition method used in the first embodiment. FIG. 3 is an optical micrograph of the optical element according to the first embodiment of the present invention. FIG. 4 is a sectional view of a Fabry-Perot modulator using a two-layer lower electrode made of gold as a second embodiment of the present invention. FIG. 5 is a diagram showing the change in the reflectance spectrum of the Fabry-Perot modulator using the two-layer lower electrode made of gold in the second embodiment due to voltage application. FIG. 6 is a cross-sectional view of a conventional optical element structure using a single-layer lower electrode made of gold. FIG. 7 is a photograph of a cross-sectional SEM structure of a conventional optical element using a single-layer lower electrode made of gold. FIG. 8 is an optical micrograph of a conventional optical element using a single-layer lower electrode made of gold.

Explanation of symbols

11, 21, 41, 71 ... glass substrate 12, 22, 42, 72 ... lower electrode 13, 15, 18, 43, 45, 47, 73, 75, 77, 410 ... Ti layer 14, 19, 44, 46, 74, 76, 411 ... gold layer 16, 23, 48, 78 ... electro-optic layer 17, 49 ... upper electrode 61 ... gas cylinder 62 ... Glass bottle 63 ... Raw material powder 64 ... Exhaust pipe 65 ... Vibrator 66 ... Transport pipe 67 ... Deposition chamber 68 ... Vacuum pump 69 ... Nozzle 79 .. Transparent electrode 81... Reflectance spectrum without voltage application 82... Reflection spectrum with 120 V voltage application state 610... Substrate 710.

Claims (16)

  A lower electrode formed on a substrate and a molded body formed by bonding the ultrafine particle brittle material by applying a mechanical impact force to the ultrafine particle brittle material supplied to the substrate, and formed on the lower electrode. An optical element comprising a waveguide and an upper electrode formed on the waveguide, wherein the lower electrode is made of a metal multilayer film.   2. The optical element according to claim 1, wherein the metal multilayer film includes a plurality of layers mainly composed of at least one of gold, silver, copper, Ir, Ru, W, and Mo and another metal layer. A featured optical element.   3. The optical element according to claim 2, wherein each of the plurality of layers has a layer thickness of 500 nm or less.   4. The optical element according to claim 1, wherein the optical element is an optical modulator or an optical switch that controls light by applying an electric signal to an electrode.   4. The optical element according to claim 1, wherein the ultrafine particle brittle material is an electro-optic material.   6. The optical element according to claim 5, wherein the electro-optic material is mainly composed of lead zirconate titanate to which lead zirconate titanate or lanthanum is added.   The method for manufacturing an optical element according to claim 1, wherein the method for manufacturing the molded body is molding by a normal temperature impact solidification phenomenon.   8. The method of manufacturing an optical element according to claim 7, wherein the method of manufacturing the molded body is an aerosol deposition method. At least one first optical element and a second optical element each including a molded body formed by bonding a mechanical impact force to an ultrafine particle brittle material supplied to a substrate and bonding the ultrafine particle brittle material; An optical integrated device integrated on the substrate,
The first optical element includes a lower electrode formed on the substrate, a waveguide made of the molded body formed on the lower electrode, and an upper electrode formed on the waveguide, An optical integrated device, wherein the lower electrode is made of a metal multilayer film.   The optical integrated device according to claim 9, wherein the second optical element is any one of a laser, an electrical-optical converter, an optical-electrical converter, an optical amplifier, an optical switch, and an optical filter. Integrated optical device. At least one of an optical element including a molded body formed by applying a mechanical impact force to an ultrafine particle brittle material supplied to a substrate and bonding the ultrafine particle brittle material and an electronic circuit are integrated on the substrate. Integrated optical device,
The optical element includes a lower electrode formed on the substrate, a waveguide made of the molded body formed on the lower electrode, and an upper electrode formed on the waveguide, and the lower electrode An optical integrated device characterized by comprising a metal multilayer film.   12. The optical integrated device according to claim 11, wherein the electronic circuit is a central processing unit or a memory.   The optical integrated device according to claim 9 or 11, wherein the ultrafine particle brittle material is an electro-optical material.   14. The optical integrated device according to claim 13, wherein the electro-optic material is mainly composed of lead zirconate titanate to which lead zirconate titanate or lanthanum is added.   12. The method of manufacturing an optical integrated device according to claim 9, wherein the manufacturing method of the molded body is molding by a normal temperature impact solidification phenomenon.   16. The method for manufacturing an optical integrated device according to claim 15, wherein the method for manufacturing the molded body is an aerosol deposition method.