JPH10253852A - Receptacle type optical fiber array - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable optical fiber array suitable for being mounted on a receptacle type optical module by using a heat resistant substrate and fixing an optical fiber and a guide pin with two types of solder having a different fusing point. SOLUTION: Silicon wafer substrate 1 is formed to have an array groove for positioning an optical fiber wire and a guide pin, and a glass wafer substrate 4 is jointed thereto in a solid phase. In addition, the optical fiber wire is inserted and fixed with solder 14 having a high fusion point. Then, the edge of the wire at the side of a connector is polished. Thereafter, a guide pin 17 is inserted and fixed with solder 20 having a low fusion point. A metallic sleeve 21 is also concurrently fixed with the solder 20. Then, the edge of the wire at the side of optical module coupling surface is polished.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber array having a receptacle type structure used for an optical module or the like used for optical parallel transmission.

[0002]

2. Description of the Related Art An optical transmission / reception module for optical parallel transmission includes:
In order to transmit optical signals using multiple light emitting or light receiving elements, an optical fiber array in which multiple optical fibers are positioned with high precision is required. Optical modules are roughly classified into two types: a pigtail type and a receptacle type.

FIG. 13A is a schematic diagram of a pigtail type optical module. Optical fiber tape 32 attached to optical fiber array 31 from optical module body 23
, And an optical connector 33 is attached to the end. Due to the difficulty in handling and heat resistance of the optical fiber tape 32, the mounting process of the optical module main body 23 on the substrate using solder reflow or the like has been made more difficult. Therefore, this mounting process has been a bottleneck in mass production and cost reduction.

FIG. 13B is a schematic view of a receptacle type optical module. In the receptacle type optical module, an optical connector 35 having an optical fiber 36 is attached to and detached from an optical fiber array 34 attached to the optical module main body 23 without fixing the optical fiber tape to the optical module main body. It has the form as described above. Unlike the pigtail type, since the optical fiber tape is not fixed, it has the advantage that it is very easy to handle in the mounting process on the board.On the other hand, the optical fiber array part that constitutes the receptacle type has optical fiber and It is necessary to simultaneously position the guide pins for connecting the optical connector with high precision. Further, in order to improve the reliability of the optical module, it is necessary to fix the optical fiber with a hermetic sealing material such as solder. Further, it is more desirable to hermetically fix the optical fiber array itself to the optical module by YAG welding or the like.

However, in the conventional receptacle type optical fiber array, a resin member is used as a part of the alignment member of the guide pin for connecting the optical fiber or the optical connector. During mounting, it was necessary to protect the resin body from heat in order to ensure high positioning accuracy, and the same handling as the pigtail type was required. In addition, similar handling was required for a receptacle type optical fiber array in which guide pins were fixed with an adhesive.

Therefore, any of the conventional receptacle-type optical fiber arrays has a problem that the problem of heat in the mounting process cannot be avoided.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and uses a heat-resistant substrate and fixes an optical fiber and a guide pin with two kinds of solders having different melting points. It is an object of the present invention to provide a highly reliable receptacle-type optical fiber array suitable for mounting on a receptacle-type optical module.

[0008]

According to a first aspect of the present invention, a heat-resistant first substrate having an alignment groove for positioning an optical fiber and a guide pin is provided so as to cover the alignment groove. The heat-resistant second substrate is solid-phase bonded to form an insertion hole for an optical fiber and a guide pin, and the optical fiber and the guide pin are inserted into the insertion hole. The receptacle type optical fiber array in which the wires are aligned to form an optical module coupling surface, and the other end surface is a guide pin for connecting to the optical connector and the optical fiber wires are aligned to form an optical connector connection surface, and at least The optical fiber on the optical module coupling surface side is fixed with a first solder, the guide pin is fixed with a second solder, and the melting point of the second solder is lower than the melting point of the first solder. It is characterized in that it.

According to a second aspect of the present invention, in the receptacle type optical fiber array according to the first aspect,
Wherein the material of the substrate is any of silicon, ceramics and glass, and the material of the second substrate is any of silicon, ceramics and glass.

According to a third aspect of the present invention, in the receptacle type optical fiber array according to the first or second aspect,
The solid-state bonding of the first and second substrates is anodic bonding.

According to a fourth aspect of the present invention, in the receptacle type optical fiber array according to any one of the first to third aspects, the first substrate and the second substrate are solid-phase bonded. The whole or a part of the outer periphery is covered with a metal sleeve.

According to a fifth aspect of the present invention, in the receptacle type optical fiber array according to any one of the first to fourth aspects, the solder for fixing the metal sleeve is the same as the second solder. It is characterized by the following.

According to a sixth aspect of the present invention, in the receptacle type optical fiber array according to any one of the first to fifth aspects, the first solder is a Pb-Sn based solder. , Wherein the second solder is a solder containing Bi-Sn as a main component.

According to a seventh aspect of the present invention, in the receptacle type optical fiber array according to any one of the first to sixth aspects, a push-pull type optical connector connection adapter is provided on the optical connector connection side. It is a feature.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a receptacle type optical fiber array according to the present invention will be described with reference to FIGS. In the figure, 1 is a first substrate, 2 is an optical fiber alignment groove, 3 is a guide pin positioning groove, 4 is a second substrate, 5 is a concave groove, 6 and 7 are insertion holes, 8 is a cutting position, and 9 is a cutting position. A base, 10 is an optical fiber tape, 11 is an optical fiber,
12 is a container, 13 is an ultrasonic oscillator, 14 is a high melting point solder,
15 is an optical fiber array chip, 16 is a polishing board, 17 is a guide pin, 18 is a container, 19 is an ultrasonic oscillator, 20 is a low melting point solder, 21 is a metal sleeve, 22 is an adhesive, 23
Is an optical module body, 24 is an IC, 25 is a multiple LD,
26 is a receptacle type optical fiber array, 27 is an optical fiber array, 28 is an MPO connector connection housing,
29 is a lens holder and 30 is a lens array.

FIG. 1 is an explanatory diagram of a cross-sectional shape of a substrate.
Although a heat-resistant material is used for the substrate 1 and the substrate 2, the same material or different materials may be used for both substrates.
In a specific example, silicon, ceramics, glass, or the like can be used. In this embodiment, an optical fiber alignment groove 2 and a guide pin positioning groove 3 are formed by using a silicon wafer as a first substrate and using a diamond blade having a V-shaped tip. The second substrate 4 forms a concave groove 5 at a position corresponding to the guide pin positioning groove 3 using a glass wafer.

Next, as shown in FIG.
And the second substrate 4 are solid-phase bonded to form an insertion hole 6 for an optical fiber and an insertion hole 7 for a guide pin. It is desirable that the solid-phase bonding be a simple and highly reliable anodic bonding. The two bonded substrates are cut at a cutting position 8 to form a base 9.

An optical fiber is inserted into each base 9. As an optical fiber, for example, a core diameter of 62.5 μm
GI type optical fiber is used, but the present invention is not limited to this. As shown in FIG. 3, an optical fiber 11 whose coating is removed and exposed using an optical fiber tape 10 may be used. As shown in FIG. 3 (A), the first substrate 1 and the second substrate 4 may have the same length, and the optical fiber 11 may be inserted from one end.
As shown in (B), the length of the second substrate 4 is slightly shorter than the length of the first substrate 1, and the optical fiber is inserted into the insertion hole using the exposed optical fiber alignment groove 2 as a guide groove. By doing so, the insertion work becomes easy.

FIG. 4 is an explanatory view of the step of fixing the optical fiber. The optical fiber is fixed to the insertion hole 6 (see FIG. 3) using high melting point solder. It is fixed by an ultrasonic solder fixing method using a high melting point ceramic solder. As shown in FIG. 4A, a container 12 filled with a high melting point solder 14 in a molten state.
The ultrasonic vibrator 13 is driven such that the end of the base 9 into which the optical fiber 11 is inserted is brought into contact with the upper surface of the ultrasonic vibrator 13 inserted from the bottom of the ultrasonic vibrator 13. Due to the pressure and the capillary force of the ultrasonic wave, the solder rises so as to be pushed up into the insertion hole of the optical fiber and the insertion hole of the guide pin.
The cross-sectional area of the gap of the insertion hole into which the optical fiber is inserted is
Since the cross-sectional area of the insertion hole where the guide pin is not inserted is sufficiently smaller, the difference in the injection speed of the solder occurs, and even if the gap of the optical fiber insertion hole is filled up with the solder, the insertion hole of the guide pin does not The height of the solder to be filled is sufficiently low. In this manner, the optical fiber is fixed to the base 9 by the high melting point solder filled in the gap of the insertion hole of the optical fiber.

As shown in FIG. 4B, the base 9 is processed into a convex shape so as to cut off a portion of the base 9 where the guide pin insertion hole is formed. When immersed in the high melting point solder 14, the opening of the insertion hole for the guide pin may be kept from touching the high melting point solder.
With this configuration, the insertion hole of the guide pin is not filled with solder.

FIG. 5 shows a cutting step. The optical fiber array chip 15 is cut out by cutting the base 9 to which the optical fiber is fixed with the high melting point solder into a predetermined length. The front and rear ends of the base 9 are appropriately removed.

As shown in FIG. 6, the cut out optical fiber array chip 15 is optically polished only at the optical connector connection surface. In the figure, a situation where the polishing is performed by rotating the polishing plate 16 is shown, but an appropriate polishing means may be used.

FIG. 7 is an explanatory view of the step of fixing the guide pins. After the guide pins are inserted into the insertion holes 7 (see FIG. 3) of the guide pins on the optical connector connection surface side of the optical fiber array chip 15, a low melting point is applied from the opposite end surface (the coupling surface side with an optical transmitting / receiving element or the like). It is fixed using solder 20. In this embodiment, ceramic solder is also used for the low melting point solder.
The fixing of the guide pins 17 with the low melting point solder 20 also used the ultrasonic solder fixing method. As shown in FIG. 7, the ultrasonic vibrator 19 is arranged such that the end of the optical fiber array chip 15 is brought into contact with the upper surface of the ultrasonic vibrator 19 inserted from the bottom of the container 18 filled with the low melting point solder 20 in the molten state. 19 is driven.
At this time, it is desirable to fix the external metal sleeve 21 at the same time. The injection amount of the solder is precisely controlled by controlling the vibration time and the amplitude of the ultrasonic vibrator 19. The low melting point solder used for fixing the guide pin 17 has a lower melting point than the previously used high melting point solder.
The temperature in the fixing step 7 does not affect the already fixed optical fiber.

FIG. 8 is a sectional view showing a state where the guide pin 17 and the metal sleeve 21 are fixed. In this embodiment, the guide pin 17 and the metal sleeve 21 are completely fixed by the low melting point solder 20, but in the embodiment shown in FIG. 9, the metal sleeve 21 is fixed on the optical fiber coupling surface side. Only a part is fixed with the low melting point solder 20, and the other part is fixed with an adhesive such as an organic adhesive. A part of the guide pin 17 may be fixed with an adhesive. As described above, even if the adhesive is used for a part of the fixing portion, there is no influence at the time of heating in a later mounting process.

In the embodiment described with reference to FIGS. 8 and 9, the end surface of the metal sleeve 21 is fixed in a state of being retracted from the end surface of the optical fiber array chip 15, but the end surface of the metal sleeve 21 is fixed to the optical fiber array chip. The metal sleeve may be fixed in a state in which it coincides with the end face of the metal sleeve.

FIG. 10 is an explanatory view showing a case where the metal sleeve 21 is fixed in a state where it is retracted from the state where the metal sleeve 21 is aligned with the end surface of the optical fiber array chip 15 and a state where the metal sleeve 21 is retracted. This is the same as the process described above. However, since the end face of the metal sleeve 21 and the end face of the optical fiber array chip 15 coincide with each other, the low melting point solder 20 can be efficiently raised in the gap between the optical fiber array chip 15 and the metal sleeve 21. Therefore, as shown in FIG. 11, it is easy to completely fix the guide pin 17 and the metal sleeve 21 only with the low melting point solder 20.

Finally, the optical module array surface of the optical fiber array chip on which the guide pins and the metal sleeve are mounted is optically polished to complete the receptacle type optical fiber array.

FIG. 12 is an explanatory diagram of a configuration example in which the optical fiber array prepared by the above-described steps is applied to a receptacle type optical module. In this example, the optical module main body 23 is provided with an IC 24 and a multiple LD (laser diode) 25 driven by the IC.
The receptacle-type optical fiber array 26 provided for connecting the optical module body 23 to the optical fiber has an optical fiber array 27 of the present invention and an MPO connector connection housing 28 integrated with each other, and is attached to a lens holder 29. ing. The output light of the multiple LD 25 is incident on each optical fiber of the optical fiber array 27 through the lens array 30. When the optical module body 23 receives signal light from an optical fiber, a multiple PD (photodiode) or the like is used instead of the multiple LD 25, and the output signal is input to the IC 24. You. The structure for connecting the optical connector to the receptacle-type optical fiber array is an appropriate structure, and is not limited to the above-described housing for connecting the MPO connector.

The terms high melting point solder and low melting point solder in the present invention are used as relative terms.
It is used to mean that the solder for fixing the optical fiber has a higher melting point than the solder for fixing the guide pins.
Further, for both the high melting point solder and the low melting point solder, for example, a high temperature solder having a melting point of 260 ° C. or more may be used. In any case, it is desirable that the melting point is higher than that of reflow soldering. In a specific example, a solder containing Pb-Sn as a main component was used as the high melting point solder, and a solder containing Bi-Sn as the main component was used as the low melting point solder.

[0030]

As is apparent from the above description, according to the receptacle type optical fiber array of the present invention, the manufacture of the receptacle type optical fiber array to which the optical connector can be detached and attached is simplified, and as a result, the handling property is improved. This makes it possible to produce a receptacle-type optical module that is difficult and does not have an optical fiber tape or the like that has low heat resistance, and has an effect that the mounting of the optical module on a substrate is further facilitated.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a cross-sectional shape of a substrate.

FIG. 2 is an explanatory diagram of a bonding state.

FIG. 3 is an explanatory diagram of an insertion step of an optical fiber.

FIG. 4 is an explanatory view of a step of fixing an optical fiber.

FIG. 5 is an explanatory view of a step of cutting a substrate.

FIG. 6 is an explanatory diagram of a polishing step of the optical fiber array chip.

FIG. 7 is an explanatory diagram of a guide pin fixing step.

FIG. 8 is a sectional view of an example of the embodiment of the receptacle type optical fiber array of the present invention.

FIG. 9 is a sectional view of another example of the embodiment of the receptacle type optical fiber array of the present invention.

FIG. 10 is an explanatory diagram of another example of the step of fixing the guide pins.

FIG. 11 is a sectional view of another example of the embodiment of the receptacle type optical fiber array of the present invention.

FIG. 12 is an explanatory diagram of a configuration example in which the optical fiber array of the present invention is applied to a receptacle-type optical module.

FIG. 13 is a schematic view of a conventional optical module.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... 1st board | substrate, 2 ... optical fiber alignment groove, 3 ... guide pin positioning groove, 4 ... 2nd board | substrate, 5 ... concave groove, 6, 7 ... insertion hole, 8 ... cutting position, 9 ... base, 10 ... Optical fiber tape, 11 ... Optical fiber strand, 12 ... Container, 13 ... Ultrasonic vibrator, 14 ... High melting point solder, 15 ... Optical fiber array chip, 16 ... Polisher, 17 ... Guide pin, 18 ... Container,
19: Ultrasonic vibrator, 20: Low melting point solder, 21: Metal sleeve, 22: Adhesive, 23: Optical module body, 2
4: IC, 25: Multiple LD, 26: Receptacle type optical fiber array, 27: Optical fiber array, 28: MPO
Connector connection housing, 29 ... Lens holder, 30
... Lens array.

Claims (7)

[Claims] 1. A heat-resistant first substrate having an alignment groove for positioning an optical fiber and a guide pin, and a heat-resistant second substrate provided to cover the alignment groove are solid-phase bonded. An insertion hole for the optical fiber and the guide pin is formed, the optical fiber and the guide pin are inserted into the insertion hole, and one end face is aligned with the optical fiber and an optical module coupling surface. Is a receptacle type optical fiber array in which guide pins for connecting to an optical connector and optical fiber wires are aligned to form an optical connector connection surface, and at least the optical fiber wire on the optical module coupling surface side is the first optical fiber array. Wherein the guide pin is fixed by the second solder, and the melting point of the second solder is lower than the melting point of the first solder. Fiber array. 2. The method according to claim 1, wherein the material of the first substrate is any of silicon, ceramics, and glass, and the material of the second substrate is any of silicon, ceramics, and glass. The receptacle-type optical fiber array described in the above. 3. The receptacle type optical fiber array according to claim 1, wherein the solid-state bonding of the first and second substrates is anodic bonding. 4. The solid-state bonding of the first substrate and the second substrate is entirely or partially covered with a metal sleeve. 2. The receptacle type optical fiber array according to claim 1. 5. The receptacle type optical fiber array according to claim 1, wherein the solder for fixing the metal sleeve is the same as the second solder. 6. The method according to claim 1, wherein the first solder is a solder containing Pb—Sn as a main component, and the second solder is a solder containing Bi—Sn as a main component. 6. The receptacle-type optical fiber array according to any one of items 5 to 5. 7. The receptacle type optical fiber array according to claim 1, further comprising a push-pull type optical connector connecting adapter on the optical connector connecting side.