JPH07159659A - Method for aligning optical semiconductor device - Google Patents

Abstract

PURPOSE:To accurately align the optical axis of an optical lens with the light emitting point of an optical semiconductor element and to obtain stable and high coupling efficiency with the optical fiber. CONSTITUTION:By image-picking up the optical semiconductor element 4 with an image pickup camera 12 through the optical lens 8 and optically performing alignment in order to align the light emitting point of the optical semiconductor element 4 disposed on a carrier base 2 with the optical axis of the optical lens 8 disposed on a mount base 1, the light emitting point of the optical semiconductor element 4 is easily and accurately aligned and adhered to the optical axis of the optical lens 8. Thus, the accurate and stable coupling efficiency with the optical fiber is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of aligning an optical semiconductor device incorporating an optical system used for information transmission, and more specifically, to an optical semiconductor device including an optical semiconductor element, an optical lens and an optical fiber. The present invention relates to the alignment method of.

[0002]

2. Description of the Related Art Optical fiber communication has the advantage of high speed and large capacity, and has been put into practical use with the progress of the information society. For this optical fiber communication, a technology for efficiently inputting light from an optical semiconductor element such as a semiconductor laser as a light source into an optical fiber is indispensable. To facilitate this,
It is generally used as a module-shaped optical semiconductor device in which an optical fiber, an optical lens, and an optical semiconductor element are integrated.

First, the structure of a conventional optical semiconductor device will be described. 2 is a side view showing the structure of a conventional optical semiconductor device, and FIG. 3 is a perspective view showing the structure of the mount base portion in detail. The optical lens 8 and the optical semiconductor element 4 are integrally provided, and the carrier base 2 on which the optical semiconductor element 4 is mounted is disposed on the mount base 1 on which the optical lens 8 is already disposed. A package 10 having a coupling portion with an optical fiber 11 which serves as an outlet.
It is sealed in. The optical semiconductor element 4 is mounted on the carrier base 2 after being bonded to the submount 3, and the lower electrode of the optical semiconductor element 4 is electrically connected to the carrier base 2 via the submount 3. To bond each of the optical semiconductor element 4, the submount 3, and the carrier base 2,
Metal brazing material is used for long-term stability. On the other hand, the upper electrode of the optical semiconductor element 4 is electrically connected to the conductive portion 6 formed on the carrier base 2 by the thin metal wire 5, and the conductive portion 6 is electrically insulated from the carrier base 2 by the insulating portion 7. Has been done.

A conventional method of manufacturing such an optical semiconductor device will be described below. First, the optical lens 8 is mounted at a predetermined position on the mount base 1. In another step, first, the optical semiconductor element 4 is bonded to the submount 3 by using a metal brazing material. After that, the submount 3 to which the optical semiconductor element 4 is adhered is adhered to the carrier base 2 by the same method, and the upper electrode of the optical semiconductor element 4 is electrically connected to the conductive portion 6 by the metal thin wire 5. In the next step, the carrier base 2 on which the optical semiconductor device 4 is mounted is aligned with the mount base 1 on which the optical lens 8 is arranged within a predetermined position range, and bonded with a metal brazing material. As a method for aligning the optical semiconductor element 4, the optical semiconductor element 4 is aligned in the left-right direction by visual inspection from above using the alignment mark 9 engraved on the mount base 1, and a metal brazing material is used. Adhere.

The optical semiconductor device is assembled by bonding the mount base 1 assembled by the above manufacturing process to a predetermined position of the package 10 with a metal brazing material.
In this optical semiconductor device, the light emitted from the optical semiconductor element 4 is condensed by the optical lens 8 and input to the core portion of the optical fiber 11 to be used as a signal. Optical semiconductor element 4
In order to efficiently and stably input the light from the optical fiber 11 to the optical fiber 11, it is necessary to accurately arrange the optical axis of the optical lens 8 and the light emitting point of the optical semiconductor element 4 in a predetermined position range.

For example, the optical fiber 11 has a core diameter of 1
When a single-mode fiber of 0 μm is used and a semiconductor laser is used as the optical semiconductor element 4, the positions of the optical lens 8 and the optical semiconductor element 4 (semiconductor laser) must be fixed with an accuracy of ± 20 μm from a predetermined position. However, the coupling efficiency with the optical fiber 11 changes remarkably, and the characteristics of the obtained optical semiconductor device change greatly. In order to suppress this, hitherto, it has been attempted to solve the problem by the positioning mark 9 engraved on the mount base 1.

[0007]

However, in the above-mentioned conventional method, since the optical lens 8 and the optical semiconductor element 4 are aligned with each other visually from above, the optical axis of the optical lens 8 cannot be accurately specified. Further, there is a problem that the positional accuracy of the positioning mark 9 engraved on the mount base 1 is determined by the machining accuracy and can usually be controlled only to about ± 20 μm. Further, since it is visually observed, there is a problem in that the positional accuracy varies due to individual differences among workers. In addition, since the optical semiconductor element 4 does not have a mark indicating a light emitting point, accurate alignment cannot be performed. Therefore, the positional accuracy required in the above-mentioned optical semiconductor device cannot be realized.

As described above, according to the conventional alignment method, the optical axis of the optical lens 8 and the light emitting point of the optical semiconductor element 4 cannot be accurately aligned, and the light from the optical semiconductor element 4 is efficiently and stably stabilized. However, there is a problem in that it cannot be manufactured so that it can be input to the optical fiber 11. An object of the present invention is to provide a method of aligning an optical semiconductor device, which enables accurate alignment of an optical axis of an optical lens and a light emitting point of an optical semiconductor element and can obtain stable high coupling efficiency with an optical fiber. That is.

[0009]

In order to solve the above-mentioned problems, a method of aligning an optical semiconductor device according to the present invention uses an image pickup camera to optically align an optical semiconductor element with an optical lens. The optical semiconductor element is imaged through the lens, and the light emitting point of the optical semiconductor element is aligned with the optical axis of the optical lens.

[0010]

According to the present invention, since the optical semiconductor element is directly imaged by the imaging camera through the optical lens, the positional deviation between the optical lens and the mount base is irrespective of the working accuracy of the mount base and other members. The position of the optical axis of the optical lens and the light emitting point of the optical semiconductor element can be accurately aligned without worrying about. Moreover, since the optical semiconductor element appears to be magnified by the magnification of the optical lens, the workability of alignment is improved. Furthermore, if a position mark indicating the light emitting region is provided in the optical semiconductor element, the influence of the variation in the position of the light emitting point in the optical semiconductor element is reduced, and the light emitting point of the optical semiconductor element is aligned with the optical axis of the optical lens. It becomes possible to match.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a structure for aligning a mount base and a carrier base of an optical semiconductor device according to an embodiment of the present invention. The basic manufacturing process in this embodiment is the same as the conventional method for manufacturing an optical semiconductor device. The difference from the conventional method is that the imaging camera 12 directly images the optical semiconductor element 4 via the optical lens 8. , To align. Hereinafter, points different from the conventional one will be described in detail.

When the carrier base 2 on which the optical semiconductor element 4 is mounted is disposed on the mount base 1 on which the optical lens 8 is disposed, when the optical base 8 is provided between the optical base 8 and the carrier base 2 on the opposite side. The optical semiconductor element 4 is imaged by the imaging camera 12 installed at a predetermined position on the extension line of the optical axis of the lens 8 to perform the alignment. The image pickup magnification of the image pickup camera 12 is set so that the outer periphery of the optical lens 8 fits on the monitor. The monitor is provided with reference regions for alignment of the optical lens 8 and the optical semiconductor element 4 on a scale according to the imaging magnification.

The image pickup camera 12 is a movable mechanism. First, the image pickup camera 12 is moved in the optical axis direction, and the image pickup camera 12 is fixed at a position where the optical lens 8 is in focus. Next, the vertical and horizontal positions of the imaging camera 12 are adjusted, the optical lens 8 is aligned with the alignment reference area of the optical lens 8 of the monitor, and the vertical and horizontal position adjustment of the imaging camera 12 is fixed. . After that, the imaging camera 12 is again moved in the optical axis direction and fixed to the position where the optical semiconductor element 4 is in focus. Next, the mesa portion showing the light emitting point of the optical semiconductor element 4 is aligned so as to coincide with the alignment reference region of the optical semiconductor element 4 of the monitor, and the carrier base 2 is bonded with the metal brazing material.

The optical semiconductor element 4 used in this embodiment is provided with a mesa portion with an accuracy of several μm according to the light emitting point during the electrode process, and the light emitting point is adjusted by adjusting the position of the mesa portion at the center of the optical lens 8. The position accuracy of was improved. In the conventional method, the positional variation between the optical lens 8 and the light emitting point of the optical semiconductor element 4 spreads to about ± 70 μm, but it becomes possible to suppress it to ± 20 μm or less by the method of the present invention. This value is sufficient to keep the coupling efficiency with the optical fiber 11 described in the conventional method stable. As a result, it becomes possible to manufacture an optical semiconductor device with the optical fiber 11 that has a stable incidence efficiency on the optical fiber 11.

As described above, according to this embodiment, since the optical semiconductor element 4 is imaged by the imaging camera 12 through the optical lens 8 and aligned, the optical semiconductor element 4 is aligned with the optical axis of the optical lens 8. The light emitting point can now be easily and accurately aligned. Further, since the optical lens 8 is directly imaged by the imaging camera 12, the optical lens 8 and the mount base 1 can be manufactured without being concerned about the positional deviation between the optical lens 8 and the mount base 1 regardless of the working accuracy of the mount base 1 and other members. Since the mesa portion of the optical semiconductor element 4 is magnified by the magnification of the optical lens 8 and is imaged on the monitor, it is easy to perform the alignment in the alignment reference area of the optical semiconductor element 4.

In this embodiment, the mesa portion formed on the optical semiconductor element 4 is used as a positioning mark, but if the same method is used after the optical semiconductor element 4 is actually made to emit light, the effect is further enhanced. It becomes remarkable. In addition, although the imaging camera 12 is movable in this embodiment, the fixed imaging camera 12 can also be used by using a jig capable of keeping the angle of the mount base 1 with respect to the imaging camera 12 constant. I know that. This is because the alignment of the optical lens 8 and the optical semiconductor element 4 is expanded by the magnification of the optical lens 8 due to the effect of the optical lens 8, which can contribute to the improvement of workability.

Further, the equipment can be automated by using the image recognition processing method using a monitor in the fixed method.

[0018]

As described above, according to the method of aligning an optical semiconductor element of the present invention, since the optical semiconductor element is directly imaged by the imaging camera through the optical lens, it is related to the working accuracy of the mount base and other members. In addition, the optical axis of the optical lens and the light emitting point of the optical semiconductor element can be accurately aligned without worrying about the positional deviation between the optical lens and the mount base, and stable high coupling efficiency with the optical fiber is achieved. Can be obtained. Moreover, since the optical semiconductor element appears to be magnified by the magnification of the optical lens, the workability of alignment is improved. Furthermore, if a position mark indicating the light emitting region is provided in the optical semiconductor element, the influence of the variation in the position of the light emitting point in the optical semiconductor element is reduced, and the light emitting point of the optical semiconductor element is aligned with the optical axis of the optical lens. It becomes possible to match.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration for aligning a mount base and a carrier base of an optical semiconductor device according to an embodiment of the present invention.

FIG. 2 is a side view showing a configuration of a conventional optical semiconductor device.

FIG. 3 is a perspective view showing in detail the structure of a mount base portion of a conventional optical semiconductor device.

[Explanation of symbols]

 4 Optical semiconductor element 8 Optical lens 11 Optical fiber 12 Imaging camera

Claims (1)

[Claims] 1. A method of aligning an optical semiconductor device, wherein light emitted from an optical semiconductor element is input to an optical fiber through an optical lens, wherein the optical semiconductor element is optically aligned with the optical lens. A method for aligning an optical semiconductor device, comprising: capturing an image of the optical semiconductor element through the optical lens with an imaging camera, and aligning a light emitting point of the optical semiconductor element with an optical axis of the optical lens.