JP2000322990A - Light receiving element package and its mounting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a metallic cover and to improve sensing accuracy in a simple structure, by applying plating for electromagnetic shield to the inner surface portion or the outer surface portion other than a land extending from the bottom of a recessed part to the outer surface, for electrically interconnecting a photosensitive elements, and providing an optically functioning aperture in the bottom of the recessed part of an injection molding component. SOLUTION: In a light receiving element package 10, a metallic cover for shielding electromagnetic noise is eliminated, and an electric black box structure where an MID (injection molding circuit component) package structure shields a photoelectric element 40 from external electromagnetic wave is employed, an aperture 21 is opened in a printed wiring board 20, and a relative position between the aperture 21 and the photoelectric element 40 is controllable with high accuracy. An MID 30 is injection-molded in a desired configuration having a recessed part for mounting the photoelectric element 40. A land pattern 31 electrically joined to a joining wire 41 of the photoelectric element 40 is formed on the inner surface of the MID 30 with plating treatment, and a circuit pattern 32 is formed on the outer surface with plating treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-receiving element package in a photoelectric sensor suitable for positioning an object in an object transfer, inspection, and assembly process in an FA. The present invention relates to a light-receiving element package capable of improving the detection accuracy of a photoelectric sensor and a method for mounting the same.

[0002]

2. Description of the Related Art Usually, in the FA transporting process or the like, a photoelectric sensor is often used to position an object to be transported by a conveyor, and a conventional photoelectric sensor having a configuration shown in FIG. Things are well known. The photoelectric sensor 1 has a case 2 in which a printed wiring board 3 on which a plurality of wiring patterns are printed is housed, and a light receiving element 4 and a light projecting element 5 are mounted on the printed wiring board 3. A metal cover 6 having a shielding function is attached so as to cover the light receiving element 4 and the light projecting element 5 in order to eliminate adverse effects of external electromagnetic noise. A lens 7 is attached to the case 2 so that the light receiving element 4 receives an optical signal from the light emitting element 5, and an aperture 8 for limiting the light receiving field of the light receiving element 4 is provided on the metal cover 6. I have.

[0003]

However, in the conventional photoelectric sensor 1, the metal cover 6 has to be soldered afterwards to the printed wiring board 3, so that automation during production is difficult and productivity is high. Is a major factor in reducing

[0004] Further, due to the variation in the processing accuracy of the printed wiring board 3 and the mounting error of the metal cover 6, etc., the light receiving element 4
If the positioning accuracy of the aperture 8 with respect to the aperture 8 is difficult, and if the positioning accuracy of the aperture 8 is reduced, the light receiving field of view will fluctuate, and this will cause a variation in detection performance in a so-called limited reflection type or regression reflection type photoelectric sensor. However, a drawback that the detection accuracy is lowered is pointed out.

The present invention pays attention to such a conventional problem and eliminates the metal cover to provide an injection molded circuit component (Mo).
lding Interconnect Device
An object of the present invention is to provide a light-receiving element package having a simple structure and excellent detection accuracy by using an MID package in which a light-receiving element is mounted (hereinafter referred to as MID) and a mounting method thereof.

[0006]

According to an aspect of the present invention, there is provided a light receiving element package in which a light detecting element is mounted, the light receiving element package having a concave portion and electrically connecting the light detecting element. A land extending from the bottom of the concave portion to the outer surface for connection to the outer surface, and at least one of the inner surface or the outer surface other than the land is formed by injection-molded circuit parts obtained by plating for electromagnetic shielding; An injection-molded circuit component has an aperture that functions optically at the bottom of the recess.

According to a second aspect of the present invention, the light receiving element is flip-chip mounted on the injection-molded circuit component such that the light receiving surface of the light receiving element faces the aperture that functions optically.

According to a third aspect of the present invention, the injection molded circuit component has a step for fixing an optical lens or an optical filter.

According to a fourth aspect of the present invention, a circuit for mounting a mounting component other than a light receiving element is provided on an outer peripheral portion of the injection molded circuit component.

According to a fifth aspect of the present invention, a mounting component other than a light receiving element is mounted on a mounting substrate having an electromagnetic shield electrode on a back surface, and fitted to the injection molded circuit component.

The invention according to claim 6 is characterized in that a concave portion is provided on the mounting surface of the injection molded circuit component so that the light receiving element can be positioned and mounted at a fixed position with respect to the aperture.

According to a seventh aspect of the present invention, the plating for the electromagnetic shield is an electrically divided mesh-like plating.

The invention according to claim 8 is provided with a concave portion for mounting the light detecting element, having a land extending from the bottom of the concave portion to the outer surface for electrically connecting the light detecting element, other than the front land. A light receiving element package comprising an injection-molded circuit component having at least one of an inner surface portion and an outer surface portion thereof plated with an electromagnetic shield is mounted on another substrate having an aperture that functions optically.

According to a ninth aspect of the present invention, the injection molded circuit component has a step for fixing an optical lens or an optical filter.

According to a tenth aspect of the present invention, a circuit for mounting a mounting component other than a light receiving element is provided on an outer peripheral portion of the injection molded circuit component.

The invention according to claim 11 is characterized in that a concave portion is provided on the mounting surface so that the light receiving element can be positioned and mounted at a fixed position with respect to the outer peripheral portion of the injection molded circuit component.

According to a twelfth aspect of the present invention, the plating for the electromagnetic shield is an electrically divided mesh plating.

Therefore, according to the present invention, the inner surface or the outer surface of the MID on which the light sensing element is mounted is plated for electromagnetic shielding, so that electromagnetic waves from outside can be effectively blocked. Metal cover can be eliminated.

Further, since the MID or the mounting substrate is provided with an aperture which faces the light receiving element and functions optically, the relative position between the light receiving element and the aperture is smaller than the conventional structure in which the aperture is provided on the metal cover. Can be managed accurately.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a light receiving element package according to the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 1 to 3 are sectional views showing a first embodiment of a light receiving element package according to the present invention. FIG. 1 is a sectional view showing a state in which a MID package and a printed wiring board are mounted. 2 and 3 are cross-sectional views showing modifications of the MID package. 4 to 8 show a light receiving element package according to a second embodiment of the present invention. FIG. 4 is a sectional view showing a state in which an MID package and a printed wiring board are mounted, and FIGS. FIG. 8 is a cross-sectional view showing a modification of the MID package, and FIG. 8 is a cross-sectional view showing a state in which the MID package and the printed wiring board are mounted. Further, FIG. 9 is a configuration explanatory view showing a photoelectric sensor manufactured by applying the first embodiment of the light receiving element package according to the present invention.

In FIG. 1, the light receiving element package 10
Are mounted on the printed wiring board 20, and the light receiving element package 10 is provided with the MI formed in a desired three-dimensional shape.
A light receiving element 40 such as a photo IC is mounted and fixed to D30 by wire bonding (joining wires are indicated by reference numeral 41), and an MID package structure in which a transparent sealing resin 42 such as a silicon resin is fixed is adopted.

In the light receiving element package 10 according to the present invention, the metal cover for shielding the electromagnetic noise is eliminated, and the light receiving element 4 has the above-mentioned MID package structure.
In addition to adopting an electric dark box structure that shields 0 from external electromagnetic waves, an aperture 21 is opened in the printed wiring board 20 so that the relative position between the aperture 21 and the light receiving element 40 can be controlled with high accuracy. It is a feature.

More specifically, since the MID 30 is mounted on a semiconductor element or connected to another circuit by soldering, a resin such as a liquid crystal polymer (LCP) having high heat resistance is used, and the light receiving element 40 is mounted. The MID 30 has a land pattern 31 electrically connected to the bonding wires 41 of the photoelectric element 40 as a conductive film plated on the inner surface and the outer surface of the MID 30.
A circuit pattern 32 having an electromagnetic shielding function is formed on the inner surface of the ID 30 and on the outer surface of the MID 30. This plating process can be formed by, for example, a selective plating method, which has been variously proposed by the one-shot method in terms of classification.

The conductive film 22 is formed on the inner surface of the printed wiring board 20, that is, the surface facing the light receiving element 40, and thus the conductive film (land pattern 31, Circuit pattern 3
2) and a structure in which the light receiving element 40 is shielded from an external electromagnetic noise by shielding the light receiving element 40 with an electric dark box (the periphery of the semiconductor is shielded by a conductive layer such as a conductive film) by the conductive film 22 formed on the inner surface of the printed wiring board 20. A), and can effectively eliminate the adverse effect of external electromagnetic waves.
It should be noted that the circuit pattern for the electromagnetic shield may be a mesh-shaped plating that is electrically divided.

Therefore, according to the above-described embodiment, the conventional metal cover can be eliminated, so that the manufacturing of the light receiving element package 10 can be automated, the productivity can be increased, and the cost advantage can be obtained. In addition to a significant improvement, the relative position between the light receiving element 40 such as a photo IC and the aperture 21 provided on the printed wiring board 20 can be controlled with high accuracy, and the detection accuracy of the photoelectric sensor can be increased.

FIGS. 2 and 3 show a modification of the above-described light receiving element package 10. As shown in FIG. 2, a step 33 for attaching an optical filter 50 to the inner surface of the MID 30 is provided. Optical filter 50
Are fixed to the MID 30 by the resin 51. As shown in FIG. 3, the steps are formed by a plurality of steps 34a,
4b and 34c are formed, and the optical filter 5
The position of 0 may be made variable.

The cross-sectional views shown in FIGS. 2 and 3 show only the light receiving element package 10, but the light receiving element 40 and the printed wiring board 2 are mounted on the printed wiring board 20 similarly to FIG.
It is mounted by performing alignment of the aperture 21 of 0.

FIGS. 4 to 8 show a second embodiment of the light receiving element package 10 according to the present invention.
MID with photoelectric element 40 such as photo IC mounted on D30
The use of the package eliminates the conventional metal cover and achieves an electromagnetic shielding function as an electric dark box structure between the MID package and the printed wiring board 20 in the same manner as in the first embodiment. The difference lies in that the photoelectric element 40 is flip-chip bonded to the MID 30 by the ball bonding portion 43 and that the aperture 35 for the photoelectric element 40 is provided in the MID 30.

That is, as shown in FIG.
The photoelectric element 40 is accommodated in an electric dark box b defined by the conductive films 31 and 32 formed on the inner and outer surfaces of the device and the conductive film 22 formed on the printed wiring board 20 to block electromagnetic noise from outside. And the structure can be simplified without adversely affecting the detection accuracy of the light receiving element 40.
It can be manufactured at low cost, and the relative position between the aperture 35 provided at the bottom of the concave portion of the MID 30 and the photoelectric element 40 can be accurately controlled.

FIG. 5 shows an embodiment in which the pattern of the conductive film to be plated on the outer surface of the MID 30 in the light receiving element package 10 of FIG. 4 is changed, and FIG.
In this embodiment, the optical lens 60 is fitted and fixed to the optical lens 60, and the step 36 for attaching the optical lens 60 is MI.
D30.

FIG. 7 shows an electronic component 70 in the MID 30 of the light receiving element package 10 according to the second embodiment.
a, 70b are mounted, and each electronic component 70a, 70b
b is wired to the circuit pattern 37 formed on the MID 30.

FIG. 8 shows an electronic component 70.
By mounting the photoelectric conversion elements c and 70d on the printed wiring board 20 and accommodating the photoelectric element 40 and the electronic components 70c and 70d in the electric dark box c, compactness is achieved.

Next, FIG. 9 shows a photoelectric sensor 80 to which the light receiving element package 10 shown in FIG. 1 is applied. The printed wiring board 20 and the light receiving element package 10 are housed in a case 81, and the printed wiring board 20 has L
A light emitting element 82 such as an ED chip, an LED drive circuit 83, and the like are mounted, and an optical lens 84 is fixed to the case 81.

In the photoelectric sensor 80,
In the light receiving element package 10, the light receiving element 40 is electromagnetically shielded by an electric dark box structure, and the relative position between the aperture 21 of the printed wiring board 20 and the light receiving element 40 can be accurately revealed. Compared with the structure of the photoelectric sensor, there is an effect that the metal cover can be eliminated, the light-receiving field of view can be controlled with high accuracy, and the detection accuracy of the photoelectric sensor 80 can be improved.

[0036]

As described above, according to the light receiving element package according to the present invention, the MID having the light receiving element mounted thereon
Since the light-receiving element is housed in the electric dark box by the conductive coating formed between the inside and outside of the substrate and the mounting substrate, and the MID facing the light-receiving element or the aperture is provided on the printed wiring board, the conventional metal is used. The cover can be abolished, the light-receiving element package can be manufactured easily and inexpensively, the accuracy of the relative position between the light-receiving element and the aperture can be precisely controlled, and the detection accuracy of the photoelectric sensor can be improved. Having.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a light receiving element package according to a first embodiment of the present invention, showing a state in which the light receiving element package is mounted on a printed wiring board.

FIG. 2 is a cross-sectional view showing a modification of the light receiving element package shown in FIG.

FIG. 3 is a cross-sectional view showing a modification of the light receiving element package shown in FIG.

FIG. 4 is a cross-sectional view showing a light receiving element package according to a second embodiment of the present invention, showing a state where the light receiving element package is mounted on a printed wiring board.

FIG. 5 is a cross-sectional view showing a modification of the light receiving element package shown in FIG.

FIG. 6 is a cross-sectional view showing a modification of the light receiving element package shown in FIG.

FIG. 7 is a cross-sectional view showing a modification of the light receiving element package shown in FIG.

FIG. 8 is a cross-sectional view showing a state in which a modification of the light receiving element package shown in FIG. 4 is mounted on a printed wiring board.

FIG. 9 is a cross-sectional view illustrating a configuration of a photoelectric sensor to which the light receiving element package according to the present invention is applied.

FIG. 10 is a cross-sectional view illustrating a configuration of a conventional photoelectric sensor.

[Description of Reference Numerals] 10 light receiving element package 20 printed wiring board 21 aperture 22 conductive film 30 MID (injection molded circuit component) 31 conductive film (land pattern) 32 conductive film (circuit pattern) 33, 34, 36 step 35 aperture 40 photoelectric Element (Photo IC) 41 Bonding wire 42 Transparent sealing resin 50 Optical filter 60 Optical lens 70 Electronic component 80 Photoelectric sensor 81 Case 82 Light emitting element 83 LED drive circuit 84 Optical lens

Claims (12)

[Claims] 1. A light-receiving element package on which a light-detecting element is mounted, the light-receiving element package includes a recess, and a land extending from a bottom of the recess to an outer surface for electrically connecting the light-detecting element;
At least one of the inner surface and the outer surface other than the land is formed of an injection-molded circuit component obtained by plating for electromagnetic shielding, and the injection-molded circuit component has an optically functioning aperture at the bottom of the concave portion. A light receiving element package characterized by the above-mentioned. 2. The light-receiving element package according to claim 1, wherein the light-receiving element is flip-chip mounted on the injection-molded circuit component such that a light-receiving surface of the light-receiving element faces an aperture that functions optically. . 3. The light receiving element package according to claim 1, wherein the injection molded circuit component has a step for fixing an optical lens or an optical filter. 4. The light-receiving element package according to claim 1, wherein a circuit for mounting a mounting component other than the light-receiving element is provided on an outer peripheral portion of the injection-molded circuit part. 5. The device according to claim 1, wherein a mounting component other than the light receiving element is mounted on a mounting substrate having an electromagnetic shield electrode on a back surface, and fitted with the injection molded circuit component. Light receiving element package. 6. The method according to claim 1, wherein a concave portion is provided on a mounting surface of the injection-molded circuit component so that the light receiving element can be positioned and mounted at a fixed position with respect to the aperture. Light receiving element package. 7. The light-receiving element package according to claim 1, wherein the plating for the electromagnetic shield is an electrically divided mesh plating. 8. A concave portion for mounting the light detecting element, a land extending from the bottom of the concave portion for electrically connecting the light detecting element to the outer surface, and an inner surface or an outer surface other than the front land. A method for mounting a light-receiving element package, comprising mounting a light-receiving element package made of an injection-molded circuit component having at least one of which is plated for electromagnetic shielding on a separate substrate having an optically functional aperture. 9. The method according to claim 8, wherein the injection-molded circuit component has a step for fixing an optical lens or an optical filter. 10. The method for mounting a light receiving element package according to claim 8, wherein a circuit for mounting a mounting part other than the light receiving element is provided on an outer peripheral portion of the injection molded circuit part. 11. A light-receiving element can be positioned and mounted at a fixed position with respect to an outer peripheral portion of the injection-molded circuit component.
2. The mounting surface according to claim 1, wherein a concave portion is provided on the mounting surface.
0. The mounting method of the light receiving element package according to any one of the above items. 12. The plating for the electromagnetic shield,
The method for mounting a light-receiving element package according to claim 8, wherein the mesh-type plating is electrically divided.