JPH10311936A - Optical module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a high light coupling efficiency equivalent to that of the conventional active alignment with a simple structure. SOLUTION: An LD mounted substrate 5 on whose surface 51 an LD 1 is attached is fitted on a guide substrate 3 provided with a guide groove 4 in whose internal part an optical fiber 2 is held and a recessed groove 7 continuing to the terminal part of the guide 4 so that the LD 1 is contained while the surface 51 is made to be a lower side and it has a space in the recessed groove 7 in a state that it is adjusted to be at the maximum position of a light output by making the surface 51 be in contact with the upper surface 31 of the guide substrate 31 and by moving the guide substrate 31 and the LD mounted substrate 5 relatively in a surface direction.

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 optical communication and the like.

[0002]

2. Description of the Related Art FIG. 14 is a sectional structural view of a conventional optical module. In FIG. 14, reference numeral 10 denotes an LD (Laser Diod).
e: semiconductor laser), 20 is an optical fiber terminal, 70 is an aspheric lens, 80 is a flanged pipe, 90 is a lens holder, 91 is a rubber holder, 92 is a case, and 93 is an LD element package. In order to couple the optical output of the LD to the optical fiber efficiently, it is necessary to accurately align the light emitting point of the LD with the core of the optical fiber (optical axis alignment). For this purpose, conventionally, the LD 10 is mounted on a package 93 to cause the LD 10 to emit light, and the holder 10 on which the optical fiber 20 is mounted is moved in three directions of x, y, and z to be coupled to the optical fiber 20. Adjust the position while monitoring the light output, and fix by welding at the position where the light output is maximized. The method of operating and emitting the LD to adjust the position while monitoring the light intensity coupled to the optical fiber and mounting the LD is referred to as an active alignment method. In this method, three axes of x, y, and z are used. Since the position adjustment is performed, the optical axis adjustment takes a long time, and the ratio of the optical axis adjustment to the cost is extremely high, and it is difficult to reduce the cost. Further, since the LD is discretely mounted in a package, it is difficult to reduce the size.

On the other hand, a planar mounting type passive alignment method has been developed as an optical module that can be reduced in size and cost. In this method, as shown in FIG. 15, since the LD 10 and the optical fiber 20 are mechanically positioned independently and accurately on the Si substrate 30, no optical axis adjustment is performed. The optical fiber 20 is a Si substrate 3
V formed by photolithography and anisotropic etching
Since it is fixed to the groove 40, three-dimensional high-precision positioning is possible. On the other hand, in order to eliminate a position error in the height direction due to a variation in the thickness of the substrate, the LD 10 is set such that the light emitting point is on the lower side, that is, the semiconductor layer crystal-grown on the semiconductor substrate is on the lower side. It is positioned with high precision by using, for example, and mounted on the mounting surface 60 of the Si substrate 30. However, in this passive alignment method, there are many other error factors such as processing of the Si substrate 30 and formation of a position recognition marker.
It is very difficult to keep the optical output of the LD below this level, and it is difficult to apply the LD to a product that is required to couple the optical output of the LD to the optical fiber with high efficiency.

Japanese Patent Application Laid-Open No. Hei 8-201664 proposes an optical module for optically coupling a semiconductor light emitting element array and a plurality of optical fibers. This optical module has two optical fibers 1 as shown in FIGS.
V-groove 30 for arranging and fixing 000 at a constant pitch
0 is provided, and an optical array coupling structure for optically coupling the end face type semiconductor light emitting element array 500 and the two optical fibers 1000 is provided. That is, the two optical fibers 1000 are connected to the V
After arranging and fixing the two optical fibers 1000 at the same pitch as the grooves 300 on the auxiliary guide substrate 800 and polishing the tips of the two optical fibers 1000 together with the auxiliary guide substrate 800, the end surface type semiconductor light emitting element array 500 is mounted on the back surface. The above-described auxiliary guide substrate 800 in which the two optical fibers 1000 are integrated with each other is mounted on the guide substrate 200. The guide substrate 200 is mounted on the base substrate 100. The end face type semiconductor light emitting element array 500 is shown in FIG.
As shown in FIG. 7, two light emitting elements 600 are formed. Each light emitting element 600 is connected to a wiring pad 700, and a bump layer 120 made of a conductive polymer adhesive is formed at the tip of the wiring pad 700. The bump layer 120 is in contact with the V-groove side wiring 400 formed on the upper surface of the guide substrate 200 in the optical module. As shown in FIG. 18, the cross-sectional structure of the end surface type semiconductor light emitting element array 500 is a p-type GaAs substrate 140.
A p-type GaAs buffer layer 150, a p-type AlGaAs cladding layer 160 having a large band gap, an AlGaAs active layer 170 serving as a light emitting layer, an n-type AlGaAs cladding layer 180, an n-type GaAs cap layer 190, and an n ⁺ -type G
It has a double hetero structure in which aAs contact layers 2000 are sequentially stacked. An n-side electrode 230 is formed on the contact layer 2000 of each light-emitting element 600, and a p-side electrode is formed on the back surface of the substrate 140. Further, the end surface type semiconductor light emitting element array 50
0 itself is separated by mechanical cutting, so that a margin 2
20 are formed.

[0005]

In the optical module based on the active alignment method shown in FIG. 14, the optical axis of the LD and the optical fiber is adjusted in three axes x, y and z. It takes time and LD10
Is discretely mounted on the package 93, which makes it difficult to reduce the size of the optical module.

In the optical module using the passive alignment method shown in FIG. 15, since there are many other error factors such as processing of the Si substrate 30 and formation of a position recognition marker, it is difficult to suppress the optical axis deviation to about 2 μm or less. There is a problem that it is quite difficult and it is difficult to apply it to a product that is required to couple the optical output of the LD to the optical fiber with high efficiency.

The optical module shown in FIG. 16 has a problem that it is difficult to realize a module that can perform optical coupling with high efficiency because there are many error factors as in the optical module using the passive alignment method. In addition, the structure of the element is limited, such as the necessity of etching the light emitting element 600 (light emitting portion) of the end face type light emitting element array 500 so as to enter the V-shaped groove 300, and its manufacture is troublesome. There is a problem. Further, since the end surface type light emitting element array 500 is in direct contact with the auxiliary guide substrate 800, the load of the end surface type light emitting element array 500 on the auxiliary guide substrate 800 is reduced.
There is a problem that a die bond load or the like is directly applied, which is not preferable in terms of reliability.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to obtain an optical module which can realize a high optical coupling efficiency equivalent to that of a conventional active alignment system with a simple structure. I do.

[0009]

According to a first aspect of the present invention, there is provided an optical module for arranging an optical fiber and a semiconductor laser chip so as to face each other and optically coupling the optical fiber and the semiconductor laser chip.
The optical fiber is held on a guide substrate, the semiconductor laser chip is attached to the LD mounting substrate in a junction-down manner, and the guide substrate has a guide groove on its upper surface for holding the optical fiber therein. And a concave groove which is connected to an end portion of the guide groove and accommodates the semiconductor laser chip mounted on the LD mounting substrate. The LD mounting substrate is
The semiconductor laser chip is attached to the surface,
The guide substrate and the LD mounting substrate are moved relative to each other in a state where the surface of the LD mounting substrate is in contact with the upper surface of the guide substrate so that the semiconductor laser chip is housed with a space in the concave groove of the guide substrate. The optical fiber is characterized by being positioned at a position where the optical output coupled to the optical fiber is maximized while moving in the plane direction, and mounted on the guide substrate.

An optical module according to a second aspect of the present invention comprises:
2. The optical module according to claim 1, wherein the LD mounting substrate is formed with electrodes for supplying power to the semiconductor laser chip continuously from the surface on which the semiconductor laser chip is mounted to the rear surface on the opposite side. It is a feature.

An optical module according to a third aspect of the present invention comprises:
2. The optical module according to claim 1, wherein the LD mounting board has an electrode formed on a surface on which the semiconductor laser chip is mounted, for supplying power to the semiconductor laser chip.
The guide substrate is characterized in that an electrode is formed on a top surface of the guide substrate at a position in contact with the electrode formed on the LD mounting substrate.

An optical module according to a fourth aspect of the present invention comprises:
2. The optical module according to claim 1, wherein the guide substrate and the LD mounting substrate are formed with step portions for engaging the both.

An optical module according to claim 5 of the present invention comprises:
In the optical module according to the first aspect, the LD mounting board is characterized in that a step portion is formed which comes into contact with an upper portion of a distal end of the optical fiber held in the guide groove of the guide board.

An optical module according to a sixth aspect of the present invention comprises:
In an optical module in which an optical fiber and a semiconductor laser chip are arranged opposite to each other and optically coupled, the optical fiber is held on a guide substrate, and the semiconductor laser chip is mounted on an LD mounting substrate. The guide substrate is penetrated from one end to the other end, and a guide groove for holding the optical fiber is formed on the upper surface inside the guide substrate. The LD mounting substrate has a semiconductor laser chip on the surface side. A mounting surface, and a cutout surface provided by cutting out a position adjacent to the mounting surface, and the cutout surface is formed on the guide substrate so that the semiconductor laser chip is arranged outside the guide substrate. The guide substrate and the LD mounting substrate are moved relative to each other in the direction of the surface while being in contact with the upper surface of the optical fiber, while being adjusted to a position where the optical output coupled to the optical fiber is maximized. In state and it is characterized by comprising attached to said guide substrate.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a schematic view showing a part of an optical module according to Embodiment 1 of the present invention, and FIG. 2 is a schematic sectional view thereof. In the figure, 1 is a semiconductor laser chip (hereinafter referred to as “LD”), 2 is an optical fiber (the tip is φ
3 is an Si substrate as a guide substrate on which the optical fiber 2 and the LD 1 are arranged;
4 is V as a guide groove for holding the optical fiber 2 inside.
The groove 5 is an LD mounting substrate (a carrier such as a Si substrate or a ceramic) on which the LD 1 is mounted, and 6 is an LD mounting substrate 5
A metallized electrode 7 formed by patterning is a groove having a depth of about 400 μm.

In the optical module according to the first embodiment, as shown in FIGS. 1 and 2, the optical fiber 2 is held on a Si substrate 3 as a guide substrate, and the LD 1 is mounted on an LD mounting substrate 5.
And the fiber end faces 2 of these optical fibers 2
1 and the light-emitting end face 11 of the LD 1 are arranged to face each other and optically coupled. The Si substrate 3 has, on its upper surface 31, a V-groove 4 for holding the optical fiber 2 therein,
A groove 7 connected to the end of the V groove 4 is provided. The V-groove 4 is formed by photolithography and anisotropic etching, and the depth is determined with high precision according to the width of the groove. The Si substrate 3 is not limited to the Si substrate as long as it has such a structure, and may be a ceramic substrate. The LD mounting substrate 5 is made of a carrier such as a Si substrate or a ceramic, and the surface
D1 is attached. The LD mounting substrate 5 has a surface 5
The LD 1 mounted on the surface 51 with the S
It is mounted on the Si substrate 3 so as to be housed with a space in the groove 7 of the i substrate 3. The surface 51 of the LD mounting substrate 5 is in contact with the upper surface 31 of the Si substrate 3.
Further, the LD mounting board 5 is moved in the lateral direction by relatively moving the Si substrate 3 and the LD mounting board 5 so that the Si substrate 3 and the LD mounting board 5 are adjusted to the position where the optical output coupled to the optical fiber 2 is maximized.
It is fixed on the substrate 3. Further, the LD mounting board 5
A metallized electrode 6 for supplying power to the LD 1 is formed in a pattern continuously from the surface 51 on which the LD 1 is mounted to the opposite surface.

The surface 13 of the LD 1 is mounted on the surface 51 of the LD mounting board 5 as shown in FIG.
That is, the surface of the LD 1 where the light emitting point 1 a is located is opposed to the surface 51 of the LD mounting board 5,
1 on the metallized electrode 6 patterned in
4 fixes LD1. Then, the LD 1 mounted on the LD mounting substrate 5 is electrically connected to another metallized electrode 6 formed on the front surface 51 of the LD mounting substrate 5 by a gold wire 8 on the back surface 12 as shown in FIG. Is done.

As the LD 1, for example, as shown in FIG. 6, a ridge 111 composed of a lower cladding layer 102, an active layer 103 and an upper cladding layer 104 grown on a semiconductor substrate 101 by MOCVD or the like, and Ridge 1
11, a current block layer in which predetermined semiconductor layers 105, 106, 107 are buried and grown, a ridge 111, and a contact layer 108 crystal-grown on the current block layer. A ridge type in which electrodes 109 and 110 are respectively formed is used. However, the LD 1 is not limited to the one having such a structure, and other types such as an SAS type can be used, and various materials such as GaAs, InP, and Si can be used. it can.

The LD mounting substrate 5 (see FIG. 4) subassembled as described above is turned upside down on the Si substrate 3 during assembly as shown in FIG. The substrate 5 is placed on the Si substrate 3 so that the surfaces thereof are aligned. Therefore, in order to allow the electrodes to be removed from the upper surface of the LD mounting substrate 5 in an upside down state, patterned metallized electrodes 6 are formed on the upper and lower surfaces and side surfaces as shown in FIG. When the LD 1 is die-bonded to the LD mounting substrate 5, the surface 13 of the LD 1 is joined to the surface 51 of the LD mounting substrate 5 as shown in FIG. The LD mounting board 5 on which the LD 1 is mounted is mounted on the Si substrate 3 with its front surface 51 facing down. This is called junction-down assembly. In this manner, the height of the light emitting point 1a of the LD 1 with respect to the surface 51 of the LD
(The total thickness of the epi layer, the LD electrode, and the plating is about 8 μm) and the thickness of the electrode 6 on the LD mounting substrate 5 and the solder 14 (about 2 μm). The error at this time is almost within 1 μm.

The optical fiber 2 has a tip of φ125 μm.
As shown in FIG. 5, the structure includes a clad 22 and a core 23 disposed at the center.
It consists of: The core 23 has a higher refractive index than the clad 22. This core 23 has an LD
The laser light emitted from 1 is incident. Thus L
The light incident by D1 is transmitted in the core 23.

Next, the procedure for assembling the optical module will be described. First, as shown in FIGS.
A substrate mounted on the D mounting substrate 5 by die bonding and wire bonding in advance is prepared.

Next, as shown in FIG. 7 (a), the optical fiber 2 is placed in the V-groove 4 of the Si substrate 3, held down, and fixed with resin. The height of the core 23 of the optical fiber 2 is accurately determined by the width of the V-groove 4 and the diameter (125 μm) of the optical fiber 2 with reference to the surface 31 of the Si substrate 3.

Then, the pre-assembled LD mounting substrate 5 is mounted on the Si substrate 3 with the surface 51 on which the LD 1 is mounted facing downward as shown in FIG. 7B. Before placing the LD mounting substrate 5 on the Si substrate 3,
A thermosetting resin is applied to a portion to be a bonding surface between the substrate 3 and the LD mounting substrate 5. Thus, the Si substrate 3 and the LD
When the mounting substrates 5 are combined so that the surfaces thereof are matched with each other, the optical fiber 2
The height of the core 23 and the height of the light emitting point 1a of the LD 1 are accurately determined. Therefore, the positional relationship in the height direction between the core 23 of the optical fiber 2 and the light emitting point 1a of the LD 1 is accurately determined.

On the other hand, the positional relationship in the horizontal direction is shown in FIG.
Even in the conventional passive alignment method shown in FIG. 5, the error tends to increase as compared with the height direction. Therefore, in the first embodiment, as shown by the arrow in FIG. 7B, only the lateral position adjustment is performed by the active alignment. FIG.
The conventional active alignment shown in FIG.
It takes a very long time because the adjustment is performed by moving in the three axial directions in the z direction. However, as in the first embodiment, the simplified adjustment in only one axial direction can be performed in a short time and at low cost. . The specific method will be described.

As shown in FIG. 7 (b), with the LD mounting substrate 5 placed on the Si substrate 3, a prober is applied to the electrode 6 (see FIG. 1 (b)) formed on the upper surface of the LD mounting substrate 5. A current is applied to the LD 1 to emit light. An optical power monitor is connected to the optical fiber 2, and while monitoring the optical output coupled into the optical fiber 2, the Si substrate 3 and the LD mounting substrate 5 are relatively moved in the direction of the arrow in FIG. Find a position where As a method of relatively moving the Si substrate 3 and the LD mounting substrate 5, for example, a precision fine moving stage on which the Si substrate 3 is mounted on a fine fine moving stage, the LD mounting substrate 5 is fixed, and the Si substrate 3 is mounted. Can be performed by moving. Then, at the position where the light output is maximum, S
The i-substrate 3 and the LD mounting substrate 5 are heated, and the resin applied to a portion to be a bonding surface between the Si substrate 3 and the LD mounting substrate 5 is cured, and the LD mounting substrate 5 is placed on the Si substrate 3.
Is fixed. Finally, when the electrodes 6 formed on the upper surface of the LD mounting substrate 5 and the leads of the package are electrically connected by gold wires, the optical module according to the first embodiment is completed.

As described above, according to the optical module of the first embodiment, the optical fiber 2 and the LD 1
The optical fiber 2 and the LD 1 are positioned by the passive alignment method in which the positioning in the height direction with respect to the optical fiber 2 and the LD 1 is performed by the active alignment method in which errors are likely to be large in the LD mounting. Since the optical axis adjustment is performed, it is possible to achieve a light coupling efficiency that is simpler and equal to that of the conventional method in which the three-axis light adjustment of x, y, and z is performed by the active alignment method. Therefore, an effect of realizing an optical module requiring high output can be obtained. Also, in this optical module,
Since the optical fiber 2 and the LD mounting substrate 5 to which the LD 1 is attached are fixed on the Si substrate 3, there is an effect that downsizing can be realized as in the conventional passive alignment method. Further, in the present optical module, since the LD 1 attached to the LD mounting board 5 is accommodated in the groove 7 provided in the Si substrate 3 with a space, the shape of the LD 1 like the conventional one shown in FIG. However, the present invention is not limited thereto, and various types can be applied, and since a load of the Si substrate 3 or the like is not applied to the LD 1, there is an effect that a highly reliable one can be obtained.

Embodiment 2 FIG. In the first embodiment, the patterned metallized electrodes 6 are formed on the upper and lower surfaces and side surfaces of the LD mounting substrate 5 as shown in FIG. 2 so that the electrodes can be taken from the upper surface of the LD mounting substrate 5 attached to the Si substrate 3. The optical module according to the second embodiment has electrodes 16 formed on both sides of groove 7 on upper surface 31 of Si substrate 3 holding optical fiber 2 as shown in FIGS. 8 and 9. In addition, the electrode 6 is formed on the surface 51 to be die-bonded on the LD mounting substrate 5 on which the LD 1 is die-bonded, and the electrode 16 formed on the Si substrate 3 when the LD mounting substrate 5 is mounted on the Si substrate 3 is It is superposed so as to be in contact with the electrode 6 formed on the LD mounting substrate 5. Thus, the LD 1 can be operated by applying a prober to the electrode 16 formed on the Si substrate 3 or by wire bonding to supply power to the LD 1. The optical module is assembled in the same manner as in the first embodiment.

As described above, according to the optical module according to the second embodiment, it is possible to assemble the optical module in the same manner as in the first embodiment. In this way, a device having a simple and equivalent optical coupling efficiency can be realized, and the electrodes 6 and 1 are provided on both the LD mounting substrate 5 and the Si substrate 3.
6 is formed so that both electrodes 6 and 16 are brought into contact with each other, and wiring to the LD 1 is performed on the electrode 16 formed on the Si substrate 3.
6 can be easily formed, and an effect that wiring to the LD 1 can be easily performed can be obtained.

Embodiment 3 In the optical module according to the third embodiment, steps 61 and 62 are formed on the Si substrate 3 and the LD mounting board 5, respectively, as shown in FIG. Parts 61, 6
The two are engaged with each other.

As described above, according to the optical module of the third embodiment, the active alignment is performed by moving the Si substrate 3 and the LD mounting substrate 5 relatively laterally in a state of being engaged with the steps 61 and 62. By adjusting the optical axis by the method, the adjustment can be performed while keeping the angle of the LD 1 and the distance between the LD 1 and the end of the optical fiber 2 constant. The effect of easily realizing a device having a high optical coupling efficiency as compared with the device is obtained.

Embodiment 4 FIG. In the optical module according to the fourth embodiment, as shown in FIG. 11, a projection 52 is provided on an LD
2, a step 53 is formed, and the step 53 is brought into contact with the fiber end face 21 of the optical fiber 2. In order to make the step 53 come into contact with the upper part of the optical fiber 2 and not to block the laser beam from the LD 1, the protrusion 52 is formed with a step surface 54 that is partially cut away. ing.

As described above, according to the optical module according to the fourth embodiment, the Si substrate 3 and the LD mounting substrate 5 are relatively moved in a state where the step 53 is in contact with the fiber end face 21 of the optical fiber 2. By adjusting the optical axis by the active alignment method by moving in the lateral direction, the adjustment can be performed while keeping the distance between the LD 1 and the end of the optical fiber 2 constant. An effect is obtained that can easily realize a device having a high optical coupling efficiency as compared with the device of the second type.

Embodiment 5 FIG. FIG. 12 is a schematic diagram showing an optical module according to Embodiment 5 of the present invention.
Is a side view thereof. In the optical module according to the fifth embodiment, as shown in FIG. 12, the optical fiber 2 is held on the Si substrate 3 and the LD 1 is attached to the LD mounting substrate 5 so that the optical fiber 2 and the LD 1 face each other. And optically coupled. The Si substrate 3 penetrates from one end to the other end and has a V-groove 4 formed on the upper surface 31, and the optical fiber 2 is held in the V-groove 4.
The LD mounting board 5 has a mounting surface 51 on the front side on which the LD 1 is mounted, and a cutout surface 55 formed by cutting out a position adjacent to the mounting surface 51. Also,
The cutout surface 55 is formed with a clearance groove 9 in which the upper part of the optical fiber 2 is accommodated. The escape groove 9 is set to be wider than the V groove 4 formed in the Si substrate 3 by about 5 μm so as to be movable in the lateral direction (the direction of the arrow in FIG. 12B). The LD mounting board 5 is mounted on the Si substrate 3 and the LD mounting board 5 with the cutout surface 55 in contact with the upper surface 31 of the Si substrate 3 so that the LD 1 is disposed outside the Si substrate 3.
Are relatively moved in the lateral direction, and the optical fiber 2 is moved.
Is mounted on the Si substrate 3 in a state where it is adjusted to the position where the optical output coupled to the substrate becomes the maximum. Note that the electrodes for driving the LD 1 are the same as those in the first or second embodiment.
It is formed by the same method as described above.

Next, a method of assembling the optical module according to the fifth embodiment will be described. The LD mounting board 5 is prepared by assembling the LD 1 junction-down on the mounting surface 51 and wiring it by wire bonding. A V-groove 4 is formed in the Si substrate 3, and the optical fiber 2 is held in the V-groove 4 and fixed with resin. Next, the LD mounting board 5 is
As shown in FIG. 2 (a), the cut face 55 is
The substrate is placed on the Si substrate 3 while being in contact with the upper surface 31 of the substrate 3. At this time, the upper part of the optical fiber 2 held in the V groove 4 of the Si substrate 3 is accommodated in the clearance groove 9 of the LD mounting substrate 5. The end surface 32 of the Si substrate 3 is in contact with the cutout side surface 56 of the LD mounting substrate 5. The height of the core 23 of the optical fiber 2 is determined by the width of the V-groove 4, and is set to match the height of the light emitting point of the LD 1 in the assembled state as shown in FIGS. And LD1
The LD mounting board 5 is moved in the horizontal direction indicated by the arrow in FIG. 12 while monitoring the light output by causing the LD 1 to emit light with a prober or the like to the electrode which supplies power to the electrode, and searching for the position where the light output becomes maximum. Is fixed on the Si substrate 3, the optical module according to the fifth embodiment is completed.

As described above, according to the optical module of the fifth embodiment, the optical fiber 2 and the LD 1
The optical fiber 2 and the LD 1 are positioned by the passive alignment method in which the positioning in the height direction with respect to the optical fiber 2 and the LD 1 is performed by the active alignment method in which errors are likely to be large in the LD mounting. The optical axis is adjusted, and the end surface 32 of the Si substrate 3 and L
Since the cutout side surface 56 of the D-mount substrate 5 is in contact with the cutout side surface 56, it is easier and has the same high light intensity as compared with the conventional case where the x-, y-, and z-axis light adjustment is performed by the active alignment method. A coupling efficiency can be achieved, and an effect of realizing an optical module requiring high output can be obtained. Further, in this optical module, since the optical fiber 2 and the LD mounting substrate 5 on which the LD 1 is mounted are fixed on the Si substrate 3, there is an effect that downsizing can be realized as in the conventional passive alignment method. . Further, in the present optical module, since the LD 1 attached to the LD mounting substrate 5 is arranged outside the Si substrate 3, the shape and the like of the LD 1 like the conventional one shown in FIG. Since the load of the Si substrate 3 and the like are not applied to the LD 1, a highly reliable LD 1 can be obtained.

[0036]

According to the optical module according to the first aspect of the present invention, in an optical module in which an optical fiber and a semiconductor laser chip are arranged to face each other and optically coupled, the optical fiber is held by a guide substrate. The semiconductor laser chip is attached to the LD mounting board in a junction-down manner, and the guide board is connected on its upper surface to a guide groove for holding the optical fiber therein and an end portion of the guide groove. And a concave groove for accommodating the semiconductor laser chip mounted on the LD mounting board. The LD mounting board has the semiconductor laser chip mounted on the surface thereof, and the semiconductor laser chip is A state in which the surface of the LD mounting substrate is brought into contact with the upper surface of the guide substrate so as to be accommodated with a space in the concave groove of the guide substrate. The guide substrate and the LD mounting substrate are moved relative to each other in the plane direction, and are positioned at a position where the optical output coupled to the optical fiber is maximized, and mounted on the guide substrate. In this manner, the so-called passive alignment method can mechanically accurately position the optical fiber and the semiconductor laser chip on the guide substrate in the height direction, and the error is large in the LD mounting. Positioning in the direction of the surface that tends to be easily performed can be accurately performed by the active alignment method. Therefore, in this optical module, the optical axis adjustment between the optical fiber and the semiconductor laser chip is
An optical axis adjustment of the three axes x, y, and z can be performed more easily and with higher accuracy than the conventional active alignment method, and high optical coupling equivalent to that of the conventional active alignment method can be obtained. It is possible to realize an optical module that requires high output. Further, in the present optical module, since the optical fiber and the LD mounting substrate on which the semiconductor laser chip is mounted are fixed on the guide substrate, there is an effect that downsizing can be realized as in the conventional passive alignment method. Further, in the present optical module, the semiconductor laser chip mounted on the LD mounting substrate is accommodated in the concave groove provided in the guide substrate in a state having a space, so that a semiconductor laser chip such as the conventional semiconductor laser chip shown in FIG. The shape and the like are not limited, and various types can be applied, and since there is no load of the guide substrate or the like applied to the semiconductor laser chip, a highly reliable semiconductor laser chip can be obtained.

According to the optical module according to the second aspect of the present invention, in the optical module according to the first aspect, the LD mounting substrate is continuously formed from a surface on which the semiconductor laser chip is mounted to a rear surface on the opposite side. An electrode for supplying power to the semiconductor laser chip is formed, and thereby, in addition to the above-described effects, a device that can easily perform wiring for supplying power to the semiconductor laser chip can be realized. The effect is obtained.

According to the optical module of the third aspect of the present invention, in the optical module of the first aspect, the LD mounting board is provided with an electrode for supplying power to the semiconductor laser chip on a surface on which the semiconductor laser chip is mounted. The guide substrate is characterized in that an electrode is formed on the upper surface of the guide substrate at a position in contact with the electrode formed on the LD mounting substrate. An effect is obtained that a device that can easily perform wiring for supplying power to the laser chip can be realized.

According to the optical module of the fourth aspect of the present invention, in the optical module of the first aspect, the guide substrate and the LD mounting substrate are formed with step portions for engaging both. This makes it possible to adjust the optical axis while keeping the angle of the semiconductor laser chip and the distance between the semiconductor laser chip and the end of the optical fiber constant. The effect that an object having efficiency can be realized is obtained.

According to the optical module according to the fifth aspect of the present invention, in the optical module according to the first aspect, the LD mounting board is in contact with an upper portion of the tip of the optical fiber held in the guide groove of the guide board. It is characterized in that a step portion is formed, and thereby,
The adjustment can be performed while keeping the distance between the semiconductor laser chip and the end of the optical fiber constant, and the effect of easily realizing a device having high optical coupling efficiency can be obtained.

According to the optical module according to the sixth aspect of the present invention, in the optical module in which the optical fiber and the semiconductor laser chip are arranged to face each other and optically coupled, the optical fiber is held by the guide substrate, The semiconductor laser chip is mounted on an LD mounting substrate, and the guide substrate is penetrated from one end to the other end,
A guide groove for holding the optical fiber is formed in the upper surface thereof, and the LD mounting board is formed by cutting out a mounting surface on which a semiconductor laser chip is mounted and a position adjacent to the mounting surface on the surface side. A notch surface provided, and the guide substrate and the LD mounting substrate are arranged in a state where the notch surface is in contact with the upper surface of the guide substrate so that the semiconductor laser chip is disposed outside the guide substrate. Is relatively positioned in the plane direction while being positioned at a position where the optical output coupled to the optical fiber is maximized, and is mounted on the guide substrate. With the so-called passive alignment method, the optical fiber and the semiconductor laser chip can be mechanically and precisely positioned on the guide substrate in the height direction. Greatly prone surface direction positioning of the difference can be accurately performed by the active alignment method. Therefore, in the present optical module, the optical axis adjustment between the optical fiber and the semiconductor laser chip can be performed more easily and more accurately than the conventional optical axis adjustment of three axes of x, y, and z by the active alignment method. The optical module can be obtained, and high optical coupling equivalent to that of the conventional active alignment method can be realized, and an optical module requiring high output can be obtained. Further, in the present optical module, since the optical fiber and the LD mounting substrate on which the semiconductor laser chip is mounted are fixed on the guide substrate, there is an effect that downsizing can be realized as in the conventional passive alignment method. Further, in the present optical module, since the semiconductor laser chip mounted on the LD mounting substrate is arranged outside the guide substrate, FIG.
The shape and the like of a semiconductor laser chip such as the conventional one shown in FIG. 1 are not limited, and various types can be applied, and the semiconductor laser chip does not receive the load of the guide substrate and the like, so that a highly reliable one can be obtained. There is.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an optical module according to Embodiment 1 of the present invention.

FIG. 2 is a schematic sectional view showing an optical module according to Embodiment 1 of the present invention.

FIG. 3 is a schematic sectional view showing an LD mounting portion of the optical module according to the first embodiment of the present invention.

FIG. 4 is a schematic diagram showing an LD mounting board which is a component of the optical module according to the first embodiment of the present invention.

FIG. 5 is a schematic diagram showing a distal end portion of an optical fiber which is a component of the optical module according to the first embodiment of the present invention.

FIG. 6 is a schematic sectional view showing a structure of an LD which is a component of the optical module according to the first embodiment of the present invention.

FIG. 7 is a schematic diagram for explaining how to assemble the optical module according to Embodiment 1 of the present invention.

FIG. 8 is a schematic diagram showing an optical module according to Embodiment 2 of the present invention.

FIG. 9 is a schematic diagram showing an LD mounting board which is a component of the optical module according to Embodiment 2 of the present invention.

FIG. 10 is a schematic diagram showing an optical module according to Embodiment 3 of the present invention.

FIG. 11 is a schematic sectional view showing an optical module according to Embodiment 4 of the present invention.

FIG. 12 is a schematic diagram showing an optical module according to Embodiment 5 of the present invention.

FIG. 13 is a schematic side view showing an optical module according to Embodiment 5 of the present invention.

FIG. 14 is a sectional view showing an optical module according to a conventional active alignment method.

FIG. 15 is a perspective view showing an optical module according to a conventional passive alignment method.

FIG. 16 is a perspective view showing another conventional optical module.

FIG. 17 is a perspective view showing an end-face type semiconductor light emitting element array which is a component of the conventional optical module shown in FIG.

FIG. 18 is a cross-sectional view showing a structure of a light emitting element portion of an end face type semiconductor light emitting element array which is a component of the conventional optical module shown in FIG.

[Explanation of symbols]

1 semiconductor laser chip (LD), 1a emission point, 2
Optical fiber, 3 Si substrate, 4 V groove, 5 LD mounting substrate, 6 metallized electrode, 7 groove, 8 gold wire, 9
Escape groove, 11 emission end face, 12 LD back face, 13 L
D surface, 14 solder, 16 metallized electrode, 21
Fiber end face, 22 clad, 23 core, 31
Surface of Si substrate, 32 Si substrate end surface, 51 LD mounting substrate surface, 52 LD mounting substrate projection, 53 LD
Step portion of mounting substrate, 54 Step surface of LD mounting substrate, 55
Notched surface of LD mounting substrate, 56 Notched side surface of LD mounting substrate, 61 Step portion on Si substrate side, 62 Step portion on LD mounting substrate side.

Claims (6)

[Claims] An optical module in which an optical fiber and a semiconductor laser chip are arranged to face each other and optically coupled to each other, wherein the optical fiber is held by a guide substrate, and the semiconductor laser chip is connected to an LD mounting substrate by a junction. The guide substrate has a guide groove for holding the optical fiber therein and an end portion of the guide groove, and the semiconductor laser chip mounted on the LD mounting substrate. The LD mounting board has the semiconductor laser chip mounted on the surface thereof, and the semiconductor laser chip is housed with a space in the groove of the guide substrate. The LD
With the mounting board surface in contact with the upper surface of the guide board,
The guide substrate and the LD mounting substrate are moved relative to each other in the plane direction while being positioned at a position where the optical output coupled to the optical fiber is maximized, and mounted on the guide substrate. Optical module. 2. The optical module according to claim 1, wherein the LD mounting substrate has an electrode for supplying power to the semiconductor laser chip continuously from a surface on which the semiconductor laser chip is mounted to a rear surface on the opposite side. An optical module characterized by being formed. 3. The optical module according to claim 1, wherein the LD mounting substrate has an electrode for supplying power to the semiconductor laser chip on a surface on which the semiconductor laser chip is mounted, and the guide substrate has An optical module, wherein an electrode is formed at a position in contact with the electrode formed on the LD mounting board on the upper surface. 4. The optical module according to claim 1, wherein the guide substrate and the LD mounting substrate are each formed with a step portion that engages the two. 5. The optical module according to claim 1, wherein the LD mounting board is formed with a stepped portion that comes into contact with an upper portion of a tip end of the optical fiber held in the guide groove of the guide board. Optical module. 6. An optical module in which an optical fiber and a semiconductor laser chip are arranged to face each other and optically coupled to each other, wherein the optical fiber is held on a guide substrate, and the semiconductor laser chip is mounted on an LD mounting substrate. The guide board is penetrated from one end to the other end, and a guide groove for holding the optical fiber is formed on the upper surface thereof, and the LD mounting board is formed on a front side thereof. Has a mounting surface on which the semiconductor laser chip is mounted, and a cutout surface provided by cutting out a position adjacent to the mounting surface, and the semiconductor laser chip is disposed outside the guide substrate. With the notched surface in contact with the upper surface of the guide substrate,
The guide substrate and the LD mounting substrate are moved relative to each other in the plane direction while being positioned at a position where the optical output coupled to the optical fiber is maximized, and mounted on the guide substrate. Optical module.