JP2001127373A - Optical module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical module which can prevent the breakage of an optical fiber or a wiring by a convenient structure as much as possible, connect accurately and optically the optical fiber and optical element, realize downsizing at almost the same size as a mounting substrate, keep a long-period realiability, and is excellent in heat radiation and high-speed operation. SOLUTION: This optical module M1 is composed of a first substrate 3 provided with an optical semiconductor element 1 and an optical wave guide body 2 to be connected optically therewith on its lower surface, and a second substrate 5 provided with an outer conductor 4 to energize to the element 1. A conductor pattern for energizing the element 1 is provided on the lower surface of the first substrate 3, and a recessed part 8 which is provided with a conductor pattern to be connected with the outer conductor 4 is formed on the second substrate 5, and then the lower surface side of the first substrate 3 is housed within the recessed part 8 so that the conductor pattern of the first substrate 3 is connected with that of the second substrate 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical module used for transmitting and receiving optical transmission such as optical fiber communication and optical interconnection.

[0002]

2. Description of the Related Art In recent years, in an optical module used for transmitting and receiving an optical signal, a metal electrode for power supply of an optical semiconductor element or the like has been used in order to simplify a component configuration to reduce costs and improve the assemblability. A mounting substrate in which V-grooves for fixing optical fibers are precisely formed is used.

Conventionally, a condensing lens has been used for optical connection between an optical semiconductor element and an optical fiber in order to obtain a desired coupling efficiency. However, both are fixed to a precision-processed mounting substrate. Thus, the optical semiconductor element and the optical fiber can be arranged very close to each other, and a desired coupling efficiency can be obtained without using a condenser lens.

In the case of an optical coupling structure using a mounting substrate, an optical fiber that is optically connected to an optical semiconductor element is pulled out of the housing as it is, and the gap between the optical fiber and a hole formed in a package through which the optical fiber is inserted is sealed by some method. I have to stop.

For example, in the optical module J shown in FIG.
An optical fiber 82 partially covered with a protective coating 83 and a glass pipe 78 covering the protective coating 83 are provided in a notch 81 and a pipe groove 75 formed on the upper surface of the package 71. A mounting substrate 80 is disposed in a concave portion 74 formed in the semiconductor device, and a semiconductor laser 72 as an optical semiconductor element is mounted and fixed on the mounting substrate 80,
The optical fiber 82 and the semiconductor laser 72 are optically connected.

After the sealing metal plate 77 and the lid 85 are sealed on the upper surface of the package 71, a low melting glass powder (not shown) disposed in the notch 81.
Is heated and melted to realize an airtight structure.
In order to heat the low melting point glass, it has been proposed to perform partial heating by means of a CO ₂ (carbon dioxide) laser or the like (for example, see Japanese Patent Application Laid-Open No. 7-63957).

In order to hermetically fix the optical element mounting board to the mounting board, a frame-shaped sealing bonding layer is formed along the periphery of the main surface of the optical element mounting board on which the optical element is fixed. And an optical module K (not shown) for providing an airtight fixing by providing a sealing bonding layer on a mounting substrate corresponding to the sealing bonding layer (for example, Japanese Unexamined Patent Publication No.
-97797).

[0008]

However, the structure of the optical module J shown in FIG. 6 employs a structure in which the optical fiber 82 and the glass pipe 78 attached thereto are disposed in the package 71. In a commonly used multilayer ceramic package, since a manufacturing method of laminating thin plates is used, a notch 81 in which an optical fiber 82 is provided and a pipe groove 7 in which a glass pipe 78 is provided.
The central axis of 5 is largely shifted with respect to the package 71.

A semiconductor laser 7 is provided in a package 71.
2 and the mounting substrate 80 on which the optical fiber 82 is mounted, the V-groove 86 formed on the mounting substrate 80 is fixed on the basis of the outer shape by the center axis of the notch 81 with respect to the V-groove 86. And the relationship with the central axis of the V-groove 86 is greatly shifted. That is, a mounting substrate made of silicon or the like is generally formed into a V-groove by etching a wafer of several inches in size and then divided into individual substrates by dicing. In such a dicing method, the outer shape accuracy is determined based on the V-groove. High processing is difficult.

Therefore, when the optical fiber is mounted on the basis of the V-groove, the positional relationship between the notch of the package, the pipe groove and the V-groove is largely displaced, so that the optical fiber and the axis of the ferrule mounted thereon are not fixed linearly. . This allows
Unnecessary bending, so-called microbending, occurs in the optical fiber, and there is a serious problem that the optical module breaks from the bending position due to an environmental change.

In order to prevent the micro-bend, it is conceivable to precisely position the shaft with respect to the notch 81 and the pipe groove 75 by cutting the optical fiber and the ferrule. In addition, it is necessary to prepare a complicated and high-performance device for performing surface treatment on the optical fiber itself and positioning the axis. This is a problem because the assembly of the optical module becomes complicated.

Further, in the optical module J, an optical fiber 82 is arranged in a notch 81 of a package 71, and a low melting point glass as a sealing material is melted and airtightly sealed in a gap between the package 71 and a lid 85. Due to the structure for obtaining the structure, an axially symmetric structure is not formed when the optical fiber 82 is fixed.
This causes a difference in the amount of thermal contraction or thermal expansion caused by the difference in the amount of the sealing material, applies stress in a specific direction of the optical fiber 82, and causes the optical fiber 82 to break.

In the case of an optical module housed in such a package, the electrical connection between the package and the package on which the semiconductor laser is mounted is generally made by wiring. Not only cannot provide a high-speed optical module, but also cause serious problems such as wire breakage.

In order to solve such a wiring problem, in the above-described optical module K, the optical element mounting board is air-tightly fixed to the mounting board. That is, a frame-shaped sealing bonding layer is provided along the periphery on the main surface of the optical element mounting substrate on which the optical element is fixed, and the sealing substrate is also sealed on the mounting substrate side corresponding to the sealing bonding layer. A stop bonding layer is provided, and airtight fixing is performed between the two.

However, in this optical module K, the above-mentioned optical fiber sealing portion is not considered at all. In general, the surface of an optical fiber is made of quartz glass or the like, and thus has poor wettability, and cannot be easily hermetically sealed using only a bonding agent such as ordinary solder. Further, even if the optical fiber can be sealed, there is a problem that the optical fiber is easily broken because only a part of the optical fiber is fixed.

Further, in the optical module K, when the mounting substrate and the optical element mounting substrate are bonded, the bonding surface is the mounting substrate,
Since the main surface of the optical device mounting board is bonded between flat surfaces, it is brittle against impact from the side, and due to the difference in thermal expansion between the mounting substrate and the It cannot be used and is easily peeled off from the joint.

In a package using a resin mold, high heat and high pressing force are applied in the process of molding the resin, and there is a danger that a large stress is applied to the mounting substrate on which the optical element is mounted and the optical fiber. Furthermore, it is difficult to hermetically seal the resin mold and efficiently radiate high heat generated in the optical element.

Accordingly, the present invention not only prevents the breakage of the optical fiber and the wiring described above with a simple configuration as much as possible, but also enables the optical connection between the optical fiber and the optical element to be performed accurately, as well as the mounting board. It is an object of the present invention to provide an optical module that can be reduced in size to a certain extent, withstands long-term reliability, has good heat dissipation, and is excellent in high-speed operation.

[0019]

In order to solve the above-mentioned problems, an optical module according to the present invention comprises a first base having at least an optical semiconductor element and an optical waveguide for optically connecting the optical semiconductor element on a lower surface. A second base provided with an external conductor for energizing the optical semiconductor element, a conductive pattern for energizing the optical semiconductor element is provided on the lower surface of the first base, and the second base is connected to the external conductor. Forming a concave portion provided with a conductive pattern to be formed,
The lower surface of the first base is accommodated in the recess so as to connect to the conductor pattern of the base.

In particular, it is preferable that the first substrate is made of a material such as silicon single crystal which can be subjected to anisotropic etching and has good thermal conductivity, and a groove for fixing the optical waveguide is formed in the upper portion. It shall be formed by anisotropic etching of the base. Further, the second substrate is preferably made of a ceramic multilayer wiring board mainly made of ceramic such as alumina or aluminum nitride.

In addition, in particular, in fitting or joining the first base and the second base, solder is used as a joining material.

In particular, when an optical fiber is used as the optical waveguide, a part of the cladding surface is metallized, so that the solder may be used for the sealing portion of the optical fiber. Therefore, airtightness can be improved.

The optical fiber is particularly supported by a ferrule mainly made of ceramic such as zirconia or alumina, and is hermetically fixed and supported by the optical fiber sealing portion of the second base.

The optical fiber sealing portion of the second base is
At least a groove or a through-hole for supporting the optical fiber is formed, and at least a part thereof is metallized.

[0025]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an exploded perspective view schematically showing the optical module M1 according to the present invention, and FIG. 2 is a front view of the optical module M1 in FIG. FIG. 3 shows a perspective view of the completed optical module M1.

The optical module M1 comprises a first base (upper base) 3 made of silicon single crystal or the like which can be anisotropically etched, and a second base (lower base) 5 made of multilayer ceramic with internal wiring. A light emitting element 1 such as a semiconductor laser or the like, which is an optical semiconductor element, and an optical fiber 2 which is an optical waveguide to be optically connected to the light emitting element 1 are provided on the lower surface 3a of the upper substrate 3. In addition, a plurality of leads 4, which are external conductors, are provided symmetrically on the lower surface 5 a of the lower base 5, and specific ones of the leads 4 are connected to the internal wiring in the lower base 5.

On the lower surface 3a of the upper substrate 3, a light receiving element 11 for monitoring, such as a photodiode, is provided.
, And the emission intensity of the light emitting element 1 can be controlled by monitoring the light emitted from the rear side of the light emitting element 1. A V groove 9 is formed on the front side of the light emitting element 1 by anisotropic etching or the like, and the optical fiber 2 is mounted in the V groove 9.

On the lower surface 3a of the upper substrate 3, conductive patterns (electrode pads) 6a, 6b for energizing the light emitting element 1 are provided.
And conductive patterns (electrode pads) 12a and 12b for energizing the light receiving element 11 are formed. The conductive patterns 6a, 6b, 12a and 12b are formed by a thin film forming process or the like in order to transmit and receive electric signals. It is formed by applying Au (gold) metallization.

The light emitting element 1 is passively aligned on the conductor pattern 6a at a precise position with respect to the V-groove 9, and is mounted and fixed by melting a solder made of an Au-Sn alloy formed on the conductor pattern 6a in advance. You. Similarly, the light receiving element 11 is mounted and fixed on the conductor pattern 12a. Further, in each optical element, a chip upper surface electrode of each optical element and the conductor patterns 6b and 12b are connected by a bonding wire such as an Au wire having a diameter of about 25 μm, for example.

An outer peripheral portion 3c on the upper surface 3b side of the upper base 3 has an inclined surface formed by anisotropic etching or the like, and the inclined surface is subjected to Au metallization by a thin film manufacturing process or the like. I have.

Optical fiber 2 optically connected to light emitting element 1
For example, a quartz-based single mode optical fiber of about φ125 μm or the like is applied, and a part of the outer circumference is precisely formed of zirconia or the like for optically connecting to an external optical connector (not shown). An optical fiber stub that is supported and fixed by a ceramic ferrule 20 having a length of about 6 mm is mounted. Further, on the exposed clad surface of the optical fiber 2, a metal plating (metallized portion) 19 of, for example, Ni or Au is partially formed over a length of, for example, about 2.8 mm in the longitudinal direction. The groove 1 formed on the lower surface 3a of the upper substrate 3
Reference numeral 0 denotes a stopper groove at the tip 2a of the optical fiber 2.

The lower substrate 5 has a recess 8 provided with conductor patterns 7a and 7b connected to the leads 4. The lower substrate 5 has conductor patterns 6a and 6b and the lower substrate 5 has conductor patterns 7a and 6b. The lower surface 3a side of the upper substrate 3 is accommodated in the concave portion 8 so as to be connected to the lower substrate 7b.

The lower substrate 5 is formed of a ceramic multi-layer substrate or the like formed by laminating ceramic thin sheets made of alumina or aluminum nitride, on which conductive patterns for electrodes and internal wiring are formed. The conductor patterns 6a, 6b, 12a, 1
A conductor pattern (electrode) 7 in which a shallow recess 13 is subjected to, for example, Au metallization, and a joining material such as a solder made of, for example, a Pb-Sn alloy is provided in advance in order to join with 2b.
a, 7b, 14a, and 14b are formed. This makes it possible to provide an optical module having excellent high-speed performance. In particular, when aluminum nitride is used as the main constituent material of the lower substrate 5, since the difference in thermal expansion between the upper substrate 3 and a silicon substrate, for example, is small and the heat transfer characteristics are excellent, the silicon substrate is When used as a mounting substrate, heat is radiated through the upper substrate 3 which is an optical element mounting substrate, which is very effective.

In the shallow recess 13, Au metallization or the like for accommodating an optical element (optical semiconductor element) provided on the upper base 1 is provided on substantially the upper half of the side wall. For fixing, for example, about 200μ width
An Au metallized groove 16 having a depth of about 60 μm and a length of about 2 mm is formed. Furthermore, A
u-metallized through hole 18 having a width of about 400 μm, a height of about 400 μm, and a length of about 800 μm, for example.
Are formed around the bottom surface of the groove 16. In order to fix and support the ferrule 20, for example, a ferrule supporting recess 17 having a width of about 1.3 mm is formed at a side end of the lower base 5.

Next, an example of an assembling procedure of the optical module M1 will be described.

First, the light emitting element 1 and the light receiving element 11 are mounted and fixed on the upper base 3, and wiring is performed on these optical elements. The metallized portion 19 of the optical fiber stub is pre-equipped with a bonding material 21 which is a solder preform made of, for example, a Pb-Sn alloy or the like from the tip 2a of the optical fiber 2. The optical fiber 2 is inserted through the through hole 18 formed in the side wall. At this time, the optical fibers 2 are aligned on the grooves 16 of the lower substrate 5.

The upper substrate 3 is composed of the conductor patterns 6a, 6b, 12a, 12b formed on the upper substrate 3 and the lower substrate 5
Conductor patterns 7a, 7b, 14a, 14b formed in
Are mounted on the lower substrate 5 so that At this time, the optical fiber 2 is aligned and supported in the V-shaped groove 9 of the upper base 3. Here, the length of the optical fiber 2 is adjusted in advance so that the end 2a comes to a predetermined position when mounted.

A bonding material 22 such as a solder preform made of a Pb-Sn alloy or the like whose dimensions have been adjusted is mounted on the metalized outer edge 3c of the upper base 3,
The lower substrate 5 is heated at about 260 ° C. At this time, it is desirable to press the upper substrate 3 against the lower substrate 5. Due to this heating and pressing, a bonding material such as a solder made of a Pb-Sn alloy or the like formed in advance on the conductor pattern on the lower substrate 5 is melted and wetted on the conductor pattern on the upper substrate 3. Further, the bonding material 21 such as a solder preform provided in the metallized portion 19 of the optical fiber 2 also melts and flows into the groove 16 of the lower substrate 5 and the metallized portion 19 of the optical fiber 2. Further, the bonding material is also filled in the through hole 18. Then, the optical fiber 2 comes into contact with the slope of the V-shaped groove 9 formed in the upper substrate 3 by pressing the upper substrate 3.

After the heating is sufficiently performed and the above-mentioned bonding material is melted, the heating of the lower substrate 5 is terminated and cooling is performed. By this cooling, the bonding material 22 is fixed and hermetically sealed. Further, in the ferrule supporting recess 17 to which the ferrule 20 is fixed, at least the lower surface 20a of the ferrule 20 is fixed with an adhesive such as an epoxy resin, and the optical module M1 as shown in FIG. 3 is manufactured.

Thus, the upper substrate 3 is mounted in the concave portion 8 of the lower substrate 5, and the optical fiber portion is also completely housed in the lower substrate 5 to have a rigid structure, and reliability can be ensured for a long period of time. . Although not shown, it is preferable to form a structure (for example, a cutout) on the lower base 5 that matches the optical connector to be fitted to the ferrule 20.

In addition, these series of operations described above are:
It is desirable to carry out in an atmosphere of an inert gas such as nitrogen. This is because optical waveguides such as optical semiconductor elements and optical fibers are deteriorated in characteristics due to the presence of moisture and the like, whereby an optical module with higher reliability can be provided.
In addition, a bonding material 22 such as a solder preform was used for sealing the upper surface side of the upper base 3, but this was made of Fe-Ni-
The same effect can be obtained by using a seal ring made of a Co alloy or the like. In this case, after pressing and heating and fixing the optical fiber portion and the electrodes in advance with solder, the seal ring is attached to the slope of the upper substrate 3. A similar hermetic seal is realized by arranging and performing seam welding. At this time, in order to perform seam welding, it is desirable to previously metallize the surface of the lower substrate 5.

Next, another embodiment will be described with reference to FIGS.
It will be described based on.

In the optical module M2 shown in FIG.
Similarly to the above-mentioned optical module M1, an upper base body provided with a light emitting element element 31 such as a semiconductor laser and a light receiving element 41 for monitoring such as a photodiode, and an optical fiber 32 optically connected to the light emitting element 31 provided on a lower surface 33a. 33 and a lower base 35 provided with a lead 34 for energizing the light emitting element 31 and the light receiving element 41.

On the lower surface 33a of the upper base 33, a V-shaped groove 39 for mounting the optical fiber 32 and the V-shaped groove 39 are provided.
And a conductor pattern 36a, 36b, 42a, 42b for energizing the optical element is provided, and a conductor pattern 37 connected to the lead 34 is provided on the lower base 35.
a, 37b, 44a, and 44b are formed, and the conductor pattern of the upper substrate 33 and the lower substrate 3 are formed.
The lower surface 33a side of the upper substrate 33 is accommodated in the recess 38 so as to be connected to the fifth conductor pattern.

The lower surface 33a side of the upper substrate 33 is formed with a convex portion 53 having an outer peripheral portion 53a formed on an inclined surface by using an anisotropic etching process, and the peripheral portion 54 has a terrace structure. Then, metallization such as Au is applied to at least the inclined surface or the terrace portion. in this way,
The optical module M2 is hermetically sealed not between the upper surface 33b of the upper substrate 33 but the lower surface 33a and the upper surface of the lower substrate 35, unlike the optical module M1.
As a result, the bonding area can be widened, so that a rigid structure can be obtained.

As the optical fiber 32, a quartz single mode optical fiber or the like is applied similarly to the above-mentioned optical module M1, and a part of its outer periphery is used for optical connection with an external optical connector (not shown). A ferrule 50 precisely formed of ceramic such as zirconia is mounted, and the optical fiber stub is supported and fixed by this. Similarly to the optical module M1, the exposed cladding surface of the optical fiber 32 is partially plated with metal plating 49.
Is given. The groove 40 formed on the lower surface 33a of the upper base 33 is a stopper groove at the tip 32a of the optical fiber 32.

A bonding material 55 such as a solder preform made of a Pb-Sn alloy or the like is arranged on the upper surface of the concave portion 38 formed in the lower base 35, and after the optical fibers 32 are aligned in the above-described procedure, The upper base 33 is fitted to the lower base 35. That is, after the upper base 33 and the lower base 35 are fitted together, the upper base 33 is heated while being pressed to melt the bonding material 55. When the bonding material 55 is melted, the bonding material 55 wets and flows on the terrace portion of the upper base 33.

At this time, until the upper end of the concave portion 38 of the lower base 35 matches the outer peripheral slope of the upper base 35 or the terrace portion, the lower surface 33a side of the upper base 33 is
5 is accommodated in the recess 38. Here, a shallow concave portion 43 and a deep concave portion 45 are formed in the concave portion 38 similarly to the optical module M1, and the light emitting element 31 and the light receiving element 41 provided on the upper base 35 are accommodated in the deep concave portion 45. You.

Conductor patterns 36a, 36b, 42a, 42b formed on the upper substrate 33 for supplying current to the optical element
And a bonding material (not shown) is previously formed on the lower substrate 35,
The conductor patterns 37a, 37b connected to the leads 34,
44a and 44b are formed so as to match each other, and melt the bonding material by heating. Upper substrate 3
When the conductor pattern formed in 3 contacts the molten bonding material, it wets and flows into the conductor pattern of the upper substrate 33. After that, the heating is terminated, and the material is cooled to fix the bonding material.

At this time, the conductor pattern formed on the upper substrate 33 and the conductor pattern on which the bonding material has been formed in advance on the lower substrate 35 coincide with each other, and the concave portion 38 is previously contacted with the conductor pattern on the upper substrate 33. It is desirable to adjust the depth and manufacture it. This adjustment can be performed by adjusting the thickness of the ceramic sheets to be laminated when the lower substrate 35 is formed of a ceramic multilayer substrate.
It is easy by shaving off the upper surface of the lower substrate 35 by polishing. Further, the amount of the bonding material previously formed on the conductor pattern of the lower base 35 is adjusted, and the upper base 33 and the lower base 35 are adjusted.
A gap may be provided between them.

As in the case of the optical module M1, the shallow recess 43 is provided with a groove 46 provided with Au metallization having a predetermined width, depth and length to support and fix the optical fiber 32. Is formed. Further, a through-hole 4 having a predetermined width, height, and length similarly subjected to Au metallization or the like.
8 are formed around the bottom surface of the groove 46. Further, a ferrule supporting concave portion 47 having a predetermined width for fixing and supporting the ferrule 50 is formed at a side end of the lower base 35. In the drawing, reference numeral 51 denotes a bonding material such as a solder preform similar to the optical module M1.

As shown schematically in FIG. 5, the lower substrate 35 is connected to an upper electrode and a lead for transmitting and receiving an electric signal to the outside and connecting to an external mounting substrate. (External electrodes) Vias 56, 58, 5 connected to 34
9, 61 and internal wiring 57, 60 are provided.
It is desirable that these vias and internal wirings have an optimally designed configuration using a microstrip line or the like for high-speed operation.

When aluminum nitride is used as the main constituent material of the lower base 35 in the same manner as in the optical module M1, the difference in thermal expansion between the upper base 33 and, for example, the silicon substrate is small, and the heat transfer characteristic is excellent. Therefore, when a silicon substrate is used as an optical element mounting substrate, it is very effective.

[0055]

As described above, according to the optical module of the present invention, the optical semiconductor device and the upper base on which the optical waveguide optically connected to the optical semiconductor device are mounted are electrically connected to the optical semiconductor device. An excellent hermetic sealing structure can be obtained by fitting the conductive pattern to be performed and the lower substrate in which the conductive pattern is connected to the external electrode by the internal wiring and joining with a joining material such as solder.

Further, by using a material having good thermal conductivity for the upper substrate and the lower substrate, high-temperature heat generated in the optical semiconductor element can be appropriately radiated, and a highly reliable optical module without characteristic deterioration. Can be provided.

Furthermore, the need for electrical connection such as wiring and complicated manufacturing steps, which have been required conventionally, are not required, and the speeding up and miniaturization of the optical module can be achieved together with the improvement in productivity.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view schematically illustrating an embodiment of an optical module according to the present invention.

FIG. 2 is a front view as viewed from P in FIG. 1;

FIG. 3 is a perspective view schematically illustrating an embodiment of the optical module according to the present invention.

FIG. 4 is an exploded perspective view for schematically explaining another embodiment of the optical module according to the present invention.

FIG. 5 is a cross-sectional view schematically illustrating another embodiment of the optical module according to the present invention.

FIG. 6 is an exploded perspective view for explaining a conventional optical module.

[Explanation of symbols]

1, 31: light emitting element (optical semiconductor element) 2, 32: optical fiber (optical waveguide) 11, 41: light receiving element 3, 33: upper substrate (first substrate) 4, 34: lead (outer conductor) 5 , 35: Lower substrate (second substrate) 6a, 6b, 12a, 12b, 7a, 7b, 14a, 1
4b, 36a, 36b, 42a, 42b, 37a, 37
b, 44a, 44b: Conductor pattern 20, 50: Ferrule M1, M2: Optical module

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Ryuji Yoneda 3-5-chome, Seika-cho, Soraku-gun, Kyoto Prefecture Inside the Central Research Laboratory, Kyocera Corporation (72) Inventor Yutaka Kuyoshi 3-chome, Seika-cho, Soraku-gun, Kyoto 5 Kyocera Corporation Central Research Laboratory F term (reference) 2H037 AA01 BA02 DA03 DA06 DA12 5F073 AB28 BA01 FA02 FA07 FA13 FA15 FA16 FA18 FA29

Claims (2)

[Claims] 1. A first base having at least an optical semiconductor element and an optical waveguide for optically connecting to the optical semiconductor element provided on a lower surface, and a second base including an external conductor for supplying a current to the optical semiconductor element. An optical module comprising: a conductive pattern for providing an electric current to the optical semiconductor element provided on a lower surface of the first base; and a concave part provided with a conductive pattern connected to the external conductor on the second base. An optical module, wherein the lower surface of the first base is accommodated in the recess so as to connect the conductive pattern of the first base and the conductive pattern of the second base. . 2. The optical module according to claim 1, wherein said first base is a single crystal silicon substrate, and said second base is a ceramic multilayer wiring board.