JP2970543B2 - Optical element alignment method and optical element module - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to element alignment, and more particularly, to an optical element alignment method that requires high-precision positioning. The present invention also relates to an optical element module which is positioned with high accuracy by applying this alignment method.

[0002]

2. Description of the Related Art A surface light emitting element module is expected to be an effective technique for parallel optical transmission capable of large-capacity and high-speed data communication. When a surface emitting device is optically coupled to an optical fiber to make a module, when mounting the surface emitting device on a package, positional accuracy of several microns or less is required to obtain sufficient coupling efficiency to the optical fiber. Become.

Conventionally, in order to perform alignment with sufficient positional accuracy, a method of visually aligning using a registration marker or the like has been adopted. As a mechanical alignment method, for example, a method described in JP-A-7-110417 is known.

FIG. 7 shows a diagram of this semiconductor light emitting device. This semiconductor light emitting device comprises a light emitting element 31 formed on a silicon substrate 30 and an opening 32 for coupling an optical fiber formed at a position corresponding to the light emitting element on the back surface of the silicon substrate.
And the tip of the optical fiber 33 is
2 to perform alignment.

[0005]

However, in such a semiconductor light emitting device, since the optical fiber is in direct contact with the back surface of the silicon substrate, the silicon substrate is easily damaged, and there is a problem in durability and reliability. It is difficult to apply when the light emitting element module is used together with an optical fiber connector or the like. Further, it is difficult to obtain sufficient accuracy quickly and reliably by a visual alignment method using a registration marker or the like, and it is difficult to automate without a large capital investment.

SUMMARY OF THE INVENTION An object of the present invention is to provide a surface light emitting element module which eliminates such conventional disadvantages, enables accurate alignment in a short time, and has sufficient durability.

[0007]

According to a method for aligning an optical element of the present invention, a method for aligning a substrate on which an optical element is mounted and a package includes forming a guide groove (or projection) on the substrate and forming the package on the package. A guide pin hole is provided, and an alignment jig for positioning the substrate in the package has protrusions (or guide grooves) corresponding to the guide grooves (or protrusions) on the substrate and guide pin holes of the package. Corresponding guide pins are provided, and the substrate is attracted to the alignment jig such that the guide groove (or projection) on the substrate is aligned with the projection (or guide groove) of the alignment jig. The positioning of the substrate and the package is performed by inserting the guide pin into the guide pin hole of the package.

According to the alignment method of an optical element of the present invention, in the alignment method of a substrate on which an optical element is mounted and a package, a guide groove (or projection) is formed on the substrate, and a guide pin hole is provided in the package. An alignment jig for positioning the substrate in a package includes a projection (or a guide groove) corresponding to a guide groove (or a projection) on the substrate and a guide pin corresponding to a guide pin hole of the package. The substrate is arranged on a package, and a guide pin of the alignment jig is inserted into a guide pin hole of the package, and a protrusion (or a guide groove) of the alignment jig and a guide groove (or a protrusion) on the substrate are provided. ), The substrate and the package are aligned.

An optical element module according to the present invention includes an optical element.
Light comprising a mounted substrate and a package mounting the substrate
An element module, wherein the optical element module includes:
Guide groove (or projection) for positioning is formed on the substrate
And a guide pin hole is formed in the package.
The position of the board with respect to the package is
In front of alignment jigs with projections and protrusions (or guide grooves)
Hold the substrate and connect the guide pins to the package
It is the position obtained by inserting it into the id pin hole,
The guide groove (or protrusion) of the substrate is aligned with the alignment.
Compatible with the jig's projection (or guide groove), the package
Guide pin holes match guide pins on alignment jigs
It is characterized by being manufactured so that.

[0010] A guide pipe provided on the optical fiber connector.
Is the same size as the alignment jig, and the package
Guide holes of the optical fiber connector
By inserting a pin, the optical fiber and the optical element
It is characterized by performing optical coupling.

Further, the optical element module according to the present invention comprises
Characterized by providing a polymer sheet on the light emitting surface of the child
And

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

[0013]

Embodiment 1 In the present invention, a guide pin hole is provided in a package on which a substrate on which an element is mounted is mounted, and an alignment jig for positioning the substrate with respect to the package with high precision is a guide pin hole of the package. Are provided. Here, a truncated pyramid or truncated cone-shaped guide groove (or projection) is formed on the substrate on which the element is mounted.
Are formed with high precision, and the alignment jig is formed with projections (or guide grooves) that match with high precision.

By inserting the guide pins of the alignment jig into the guide pin holes of the package, an initial alignment between the substrate on which the elements are mounted and the package is obtained, and the guide grooves (or projections) on the substrate and the projections ( Or the guide groove) is used to perform positioning with higher accuracy. Therefore, alignment can be easily performed with sufficient positional accuracy.

[0015]

Embodiment 1 Embodiment 1 of the present invention is an example in which Embodiment 1 is applied to a surface emitting element module. FIG. 1 is a perspective view showing a surface emitting element module and an alignment method thereof according to Embodiment 1 of the present invention. In the figure, 1 is a surface emitting element, 2
Denotes a silicon substrate, 3 denotes a package, 4 denotes an alignment jig, 5 denotes an alignment guide groove, 6 denotes an alignment projection, 7 denotes a guide pin, and 8 denotes a guide pin hole.

The surface emitting device module according to the first embodiment of the present invention comprises a silicon substrate 2 on which a surface emitting device 1 such as a surface emitting laser or a surface emitting diode is accurately mounted, and a package 3 for mounting the same. When mounting the substrate 2 on the package 3, the alignment jig 4
Is used.

Here, on the silicon substrate 2, guide grooves 5 having a truncated pyramid shape for alignment are provided at both ends thereof, and a projection-like structure 6 compatible with the alignment jig 4 is formed. . The alignment between the substrate and the package is performed by the connection between the protrusion 6 and the groove 5 and the guide pin 7 and the guide pin hole 8.

Next, a method for aligning the surface light emitting element module according to the first embodiment will be described with reference to the schematic diagram of FIG. First, the projection-like structure 1 of the alignment jig 9
3 is fitted into the truncated pyramid V-shaped groove 14 of the silicon substrate 12, and the alignment jig 9 is formed by a method such as vacuum suction.
The silicon substrate 12 is held.

The guide pin 10 of the alignment jig 9
Is inserted into the guide pin holes 16 of the package 11, the silicon substrate 12 is fixed to the package 11 using an adhesive, solder, or the like that has been applied in advance, and the alignment jig 9 is removed. Since the position of the silicon substrate is easily mechanically determined by the projection-like structure 13 and the guide pin 10 of the alignment jig, it is possible to easily align and fix the surface emitting element with sufficient positional accuracy. .

Next, a method of manufacturing the silicon substrate 2 on which the surface light emitting element 1 is mounted will be described. The surface light emitting element 1 is mounted on a silicon substrate 2 so as to emit light vertically upward. As a method of mounting the surface light emitting element 1 on the silicon substrate 2 with high accuracy, for example, a method of flip chip mounting in which a solder bump is formed at a desired position on the silicon substrate and is fused to a gold plating pad on the surface light emitting element is known. Have been. The truncated pyramid-shaped guide groove for alignment is formed as follows using the etching anisotropy of the silicon (100) plane. After masking with a metal thin film or the like, when the (100) plane of silicon is etched using a potassium hydroxide solution, the angle from the horizontal plane is 54.7 due to the plane orientation dependence of the etching rate at the opening of the mask. A truncated pyramid-shaped groove is formed so as to be constantly constant. In this case, since the positions of the guide grooves and the solder bumps are set by photolithography, the positions of the surface light emitting elements and the guide grooves on the silicon substrate can be determined with high accuracy of several microns.

According to the first embodiment of the present invention, there is no need to form a groove on the back surface of the substrate as in the example of FIG. Cheap. Further, the silicon substrate used in Example 1 also functions as a submount having a heat sink and a wiring portion of the surface emitting element.

The protrusions of the alignment jig of the first embodiment
Although it is processed into a truncated pyramid shape that fits into the guide groove, it is not limited to this shape, and any shape may be used as long as it is convex. The material of the alignment jig is not particularly limited as long as it can form the projection-like structure and the guide pin with high precision, such as plastic and metal.

When a method that requires heating, such as soldering, is used to fix the silicon substrate on which the light emitting element is mounted to the package, if the package and the alignment jig are made of materials having similar thermal expansion coefficients, alignment by thermal expansion can be achieved. Accuracy can be prevented from deteriorating.

In the alignment method of Example 1 which is a specific example of Embodiment 1 of the present invention, a groove for embedding an element in a package is provided. However, the present invention is not limited to this. Alignment is also possible.

In addition, the substrate is adsorbed to the alignment jig for alignment, but the substrate on which the elements are mounted is previously arranged on the package, and the guide pins of the alignment jig are inserted into the guide pin holes of the package. The alignment may be performed by aligning a guide groove (or protrusion) provided on the substrate with a protrusion (or guide groove) of the alignment jig.

As the optical element, a semiconductor laser, a surface emitting semiconductor laser, a light emitting diode, an array of these light emitting elements, and the like can be applied, but the present invention is not limited thereto.
The present invention can be applied to any optical element that requires highly accurate alignment.

As the alignment projection formed on the alignment jig, any structure such as a truncated pyramid, a sphere, and a pin can be used as long as the shape is suitable for the groove formed on the substrate. Also, the alignment jig has a projection,
Although the guide groove is formed on the substrate, the alignment jig may have a groove and a protrusion may be provided on the substrate.

[0028]

Embodiment 2 FIG. 3 is a schematic diagram showing Embodiment 2 of the present invention. The difference from the first embodiment is that the projection of the alignment jig is formed by press-fitting a conical pin 17 with its tip aligned with the guide groove on the substrate. The configuration is the same as in the first embodiment. In this case, the guide groove 18 on the silicon substrate is formed to have a square opening, and the same alignment effect as described above can be obtained.

[0029]

Third Embodiment FIG. 4 is a schematic diagram showing a third embodiment of the present invention. The difference from the above-described embodiment is that the projection of the alignment jig is formed by press-fitting the bearing ball 19, and the other configuration is the same as that of the above-described embodiment. In the third embodiment, the shape of the protrusion can be precisely processed by the bearing ball 19.

[0030]

Second Embodiment A connection between a surface light emitting element module formed by the alignment method of the present invention and an optical fiber connector will be described using a fourth embodiment.

[0031]

Fourth Embodiment FIG. 5 is a schematic diagram showing a fourth embodiment of the present invention. In the figure, 20 is a package, 21 is a guide pin hole,
22 is a guide pin, 23 is an optical fiber connector, 24 is a substrate, 25 is a surface emitting element, and 26 is an optical fiber. The surface emitting element module of this embodiment is manufactured by the same steps as those of the first embodiment. The difference from the first embodiment is that the guide pin hole 21 of the package 20 of the surface emitting element module is provided.
Is formed in the same size as the optical fiber connector 23 having the guide pin 22, and the position of the surface light emitting element 25 on the substrate 24 is set to correspond to the optical fiber of the optical fiber connector 23.

According to the above-described alignment method, the position of the surface light-emitting element can be determined with high precision with respect to the guide pin, so that the surface light-emitting element can be coupled to the optical fiber connector with sufficient coupling efficiency. As the optical fiber connector, an optical fiber array connector in which a plurality of optical fibers are bundled can be used, and an array of surface light emitting elements can be mounted on a module and coupled. In this case as well, high coupling efficiency between the surface light emitting elements on the array and the optical fibers can be obtained by a single simple alignment method as described above.

In the present invention, the optical fiber and the silicon substrate on which the surface light emitting element is mounted do not need to be in contact with each other and can be individually fixed, so that a surface light emitting element module with improved durability can be manufactured. become.

The package used for the surface light emitting element module has a guide pin hole having the same size as the guide pin of the optical fiber connector so that the package can be used in combination with an optical fiber connector having a guide pin. The material of the package is not particularly limited, such as plastic and metal.

[0035]

Embodiment 5 FIG. 6 is a schematic view showing Embodiment 5 of the present invention. In the surface light emitting device module similar to that of the fourth embodiment, a polymer sheet 29 having a thickness of about 0.2 mm is provided on the surface light emitting device 27. The gap formed between the substrate on which the surface light emitting element is mounted and the package is sealed with resin. When a surface emitting laser is used as a surface emitting element and an optical fiber is combined with the optical fiber, it is known that laser light may be reflected at the end face of the optical fiber due to a difference in refractive index from air, and noise may be induced by the reflected return light. Have been. As in the present embodiment, a polymer sheet is provided on the surface light emitting element, and air present between the surface light emitting element and the end face of the optical fiber is removed, thereby suppressing the reflection at the end face of the optical fiber and returning reflected light. Noise caused by the noise can be reduced.

[0036]

According to the present invention, following the initial alignment using the guide pin holes of the package and the guide pins of the alignment jig, the projection (guide groove) structure of the alignment jig is aligned with the guide groove (projection structure) on the substrate. Alignment with higher precision than alignment using only guide pins can be performed.

Further, in the surface light emitting device module detachable from the optical fiber connector, the optical devices can be aligned with sufficient positional accuracy.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a surface emitting element module and an alignment jig according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating an alignment method according to the first embodiment of the present invention.

FIG. 3 is a schematic diagram illustrating an alignment jig according to a second embodiment of the present invention.

FIG. 4 is a schematic diagram illustrating an alignment jig according to a third embodiment of the present invention.

FIG. 5 is a schematic view illustrating a surface light emitting element module and an optical fiber connector according to a fourth embodiment of the present invention.

FIG. 6 is a schematic view showing a surface emitting element module and an optical fiber connector according to a fifth embodiment of the present invention.

FIG. 7 is a conceptual diagram illustrating a conventional method of aligning a surface emitting element.

[Explanation of symbols]

 Reference Signs List 1 surface emitting element 2 silicon substrate 3 package 4 alignment jig 5 alignment guide groove 6 alignment protrusion 7 guide pin 8 guide pin hole 9 alignment jig 10 guide pin 11 package 12 silicon substrate 13 alignment protrusion 14 guide groove Reference Signs List 15 surface light emitting element 16 guide pin hole 17 pin formed in a conical shape 18 guide groove 19 bearing ball 20 package 21 guide pin hole 22 guide pin 23 optical fiber connector 24 substrate 25 surface light emitting element 26 optical fiber 27 surface light emitting element 28 Optical fiber 29 Polymer sheet 30 Silicon substrate 31 Light emitting element 32 Opening for optical fiber coupling 33 Optical fiber

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02B 6/42 G02B 7/00

Claims (11)

(57) [Claims] 1. A method for aligning a substrate on which an optical element is mounted with a package, wherein a guide groove (or projection) is formed on the substrate, a guide pin hole is provided in the package, and the substrate is mounted on the package. An alignment jig for positioning is provided with a projection (or a guide groove) corresponding to a guide groove (or a projection) on the substrate and a guide pin corresponding to a guide pin hole of the package. After the substrate is attracted to the alignment jig such that the projection (or the guide groove) of the alignment jig is aligned with the projection (or the guide groove) of the alignment jig, the guide pin of the alignment jig is inserted into the guide pin hole of the package. An alignment method for an optical element, comprising: positioning a substrate and a package. 2. A method for aligning a substrate on which an optical element is mounted with a package, wherein a guide groove (or projection) is formed on the substrate, a guide pin hole is provided on the package, and the substrate is mounted on the package. An alignment jig for positioning is provided with a projection (or a guide groove) corresponding to a guide groove (or a projection) on the substrate and a guide pin corresponding to a guide pin hole of the package. The substrate and the package are provisionally arranged, the guide pins of the alignment jig are inserted into the guide pin holes of the package, and the protrusions (or guide grooves) of the alignment jig are aligned with the guide grooves (or protrusions) on the substrate. An alignment method for an optical element, comprising: 3. The alignment method according to claim 1, wherein the optical element is a light emitting element or a surface light emitting element. 4. The method according to claim 1, wherein the substrate is a silicon substrate. 5. The optical element alignment method according to claim 1, wherein the projection of the alignment jig is a pin or a ball bearing processed into a conical shape. 6. A substrate on which an optical element is mounted and said substrate is mounted.
An optical element module comprising a package
In the light storage element module, a positioning gas is provided on the substrate.
Guide grooves (or protrusions) are formed, and
A pin hole is formed, and the base for the package is formed.
The position of the plate has guide pins and protrusions (or guide grooves).
Holding the substrate on an alignment jig
Inserting pins into the guide pin holes of the package
Position obtained from the guide groove (or protrusion) of the substrate.
K) is the projection (or guide groove) of the alignment jig
And the guide pin holes of the package are aligned
Make sure that it is made to fit the guide pin of the
An optical element module characterized by the following. 7. The optical element module according to claim 6, wherein said optical element is a light emitting element or a surface light emitting element. 8. The optical element module according to claim 6, wherein said substrate is a silicon substrate. 9. The optical element module according to claim 6, wherein the projection of the alignment jig is a pin or a ball bearing processed into a conical shape. 10. A guide provided on an optical fiber connector.
Doping pin is the same size as the alignment jig,
Insert the optical fiber connector into the guide pin hole of the package.
The optical fiber and the optical element are inserted by inserting a guide pin.
8. The optical coupling of the element is performed.
10. The optical element module according to 8 or 9. 11. The optical element module according to claim 7, wherein a polymer sheet is provided on a light emitting surface of the optical element.