JP2002341113A - Compound optical device and method of manufacturing for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compound optical device subjected to the improvement in the reliability of the device, such as the improvement in protection characteristics from the moisture or the like of the photodetecting surfaces of optical elements and the improvement in the reliability of bump connection by adopting the constitution in which the photodetecting surfaces of the optical elements face a substrate. SOLUTION: This compound optical device which irradiates an object to be irradiated with light and receives the reflected light thereof has a substrate 10 which has at least aperture 12 for a photodetecting section, the photodetecting section 43 which is arranged on the first surface of the substrate 10 in such a manner that the photodetecting surface 42 faces the interior 12 of the aperture for the photodetecting section and optical members (20 and 30) which are arranged on the second surface of the substrate, emit the exit light LT from a light emitting section 51 toward the object to be irradiated and couples the reflected light from the object to be irradiated through the aperture 12 for the photodetecting section to the photodetecting section 42. At least the photodetecting surface 42 of the photodetecting section 43 is sealed by a resin 44.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite optical device and a method of manufacturing the same, and more particularly, to an optical pickup device for an optical disk system such as a CD (compact disk), MD (mini disk), DVD (digital versatile disk). And a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, in an optical disk system such as a CD, MD, or DVD, a semiconductor laser or an integrated optical element in which a semiconductor laser is integrated with an optical component and a light receiving element is used as a light source.

[0005] CD and MD use a 780 nm band semiconductor laser, while DVDs use a 660 nm band semiconductor laser. Further, as a light source of a next-generation optical disk, adoption of a group III nitride semiconductor laser emitting in the 400 nm band is expected to be promising.

In a composite optical device, a semiconductor laser of each of the above wavelengths and a photodiode (PD) for receiving light (RF light) reflected from a disk, or a PDIC (photodiode IC) further provided with an arithmetic function ) And optical components for adjusting the optical axis and beam characteristics of the light to the optical disk.

FIG. 9A is a schematic diagram showing the configuration of an optical pickup device to which the above-described conventional composite optical device is applied. For example, the semiconductor laser 15 is placed in a concave portion 111 provided in a substrate 110 such as a package substrate made of resin or the like.
1 and a PDIC 143 on which a PD light receiving surface 142 is formed are fixed.
It is electrically connected to the terminal T by a wiring (not shown) or the like. The diffraction grating 121, the hologram 123, the convex lens 122, and the concave lens (12
4, 125) is mounted. On the upper surface of the multi-lens 120, for example, a spectral separation surface (131, 133, 134) such as a polarization separation surface for separating p-polarized light and s-polarized light or a total reflection surface, and a half-wave plate 132
Multi-prism 13 made of a glass laminate having
0 is attached.

For example, the above submount is made of a silicon block, and the reflective surface 150a is formed by etching or the like.
Are formed. The laser light LT emitted from the semiconductor laser 151 is reflected by the reflection surface 150a, is taken out of the composite optical device via the diffraction grating 121, the convex lens 122, and the spectral surface 131, and is extracted by the collimator lens C.
L, and irradiates the optical recording film of an optical disk D such as a magneto-optical disk via the objective lens OL.

[0007] The reflected light (return light) from the optical disk is bent in the traveling direction by the spectral surface 131, and is reflected by the half-wave plate 13.
Proceed in two directions. A part of the light reaching the surface of the half-wave plate 132 is reflected and a part is transmitted. For example, a part of the s-polarized light component is reflected on the surface of the half-wave plate 132, the astigmatism is enlarged by the hologram 123 (equivalent to a cylindrical lens), and the light is incident on the light receiving surface 142 of the PDIC 143. On the other hand, the component transmitted through the half-wave plate 42 has its polarization plane rotated and proceeds to the spectral plane (133, 134). For example, by rotating the polarization plane by 45 °, the p-polarized component transmits 100% and the s-polarized
% Reflection, and so that the p-polarized component is reflected 100% on the spectral surface 134. Spectral surface (13
3, 134) is reflected by the convex lens (124, 12).
The light enters the light receiving surface 142 of the PDIC 143 via 5).

The light receiving surface 142 of the PDIC 143 is
For example, it has a layout as shown in FIG. That is, on the light receiving surface 142, a four-divided light receiving region 142a, a two-divided light receiving region (142b, 142c), and a single light receiving region (142d, 142e) are provided, respectively. Are reflected by the four-divided light receiving region 142a and the two-divided light receiving region (142b, 1
42c) as three spots,
The component reflected on the light receiving area 142d enters the single light receiving area 142d as one spot, and the component reflected on the spectral surface 134 enters the single light receiving area 142e as one spot.

A light receiving signal of each light receiving area is generated on the PDIC 143, a predetermined arithmetic processing is performed, and a function of detecting an RF signal, a focus error signal, a tracking error signal, and the like of the optical disk is contained in the PDIC 1 chip.

In the above-described composite optical device, the light receiving surface of the light receiving element (PDIC) does not face the substrate surface, but is arranged on the substrate with the light receiving surface facing the upper surface. This is because the arrangement (alignment) of the light receiving element with respect to the light spot to be detected is easy, and the configuration of necessary members is simple. In the optical pickup device for an optical disk as shown in FIG. 9, the number of light spots to be detected is large, and the alignment accuracy required for a light receiving element that divides and receives light is extremely strict.

FIG. 10 is a schematic configuration diagram of an optical device having a configuration in which a light receiving surface of a light receiving element and a substrate face each other. Light receiving element 20
The light receiving surface 205 and the substrate 200 are opposed to each other, and a prism 201 and an optical fiber support 204 are arranged in the gap therebetween, and the optical fiber 203 is inserted through the optical fiber support 204. The light LT emitted from the optical fiber 203 is reflected by the spectral surface 201a of the prism 201 and enters the light receiving surface 205. This is an example of optical mounting, but it is a configuration in which one light spot is simply placed on the light receiving surface, and one light spot only needs to hit somewhere on one light receiving surface, so the required alignment accuracy Is extremely lower than that of the optical disk.

As described above, when the light receiving element is arranged so that the light receiving surface of the light receiving element does not face the substrate,
Alignment is easy, and even if the required accuracy of alignment is increased by increasing the functionality of the light receiving element, it can be easily handled. However, in recent years, an arrangement has been required in which the light receiving surface of the light receiving element is opposed to the substrate and the alignment accuracy is improved. The reason and the solution will be briefly described. For example, in the case of optical discs, shorter wavelengths of light sources and higher NAs of objective lenses have been promoted due to the requirements for recording methods and large recording densities. Is becoming more complex. When this is applied to a light receiving element, the number of divided patterns of the light receiving section is increased, and the size of one divided area is reduced. For this reason, more precise alignment accuracy is required for the light receiving element mount.

One of the methods to meet this demand is active alignment, which performs alignment while actually receiving light. Thereby, more precise alignment accuracy can be achieved. To perform active alignment, instead of arranging optical components and light-receiving elements on the same side of the board as in the past, light-receiving elements are arranged on one side of the board and optical parts are arranged on the other side. I do. Furthermore, an opening for transmitting light is provided on the substrate, and a light receiving element is mounted on the substrate with a flip chip using a relay substrate,
While receiving the light, the relay board on which the light receiving element is mounted is fixed to the board.

[0014]

However, in the optical device having the configuration in which the light receiving surface of the light receiving element is opposed to the substrate to enable active alignment as described above, the reliability cannot be said to be sufficient. It is desired to improve. What is desired to improve reliability is protection of the light receiving surface of the light receiving element from moisture and the like.

In a configuration in which a bump is used to mount the light receiving element from the light receiving surface side by flip chip, it is desired to improve the reliability of the bump connection. In an optical device mounted with a light receiving element by bump connection, a substrate,
The light receiving element and the bump connection portion are affected by temperature changes in the storage and use environment. That is, when subjected to a temperature change, all substances expand and contract in accordance with the thermal expansion coefficient inherent to the material. FIG. 11 is a schematic diagram showing the state of the light receiving element PD that is flip-chip bonded, the substrate Sub on which the element is mounted, and the bumps B that mediate it. The degree of expansion and contraction of the light receiving element PD, the substrate Sub, and the bump B due to the temperature change depends on each material.

FIG. 11A is an enlarged view of a bump portion at the time of assembly, and this state is used as a reference. When the degree of expansion of the substrate Sub and the light receiving element PD is greater than that of the bump B, as shown in FIG. 11B, a so-called tensile stress is applied to pull the bump B. On the other hand, when the degree of shrinkage of the substrate Sub and the light receiving element PD is higher than that of the bump B, FIG.
As shown in FIG. 7, a compressive stress for shrinking the bump B is applied.

When the number of times the temperature changes as described above increases, the bump is subjected to a large number of times of stretching and contracting, and eventually causes so-called metal fatigue and cracks are introduced. In some cases, disconnection occurs, and the electrical and physical connection between the substrate and the light receiving element breaks down. This is the bump degradation mode and mechanism in flip chip bonding. In FIG. 11, for simplicity, the light-receiving element and the substrate both expand and shrink more than the bumps.
It goes without saying that either one can be a pull.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is therefore an object of the present invention to enable an active alignment which can be aligned with high accuracy by making a light receiving surface of a light receiving element opposed to a substrate. In the optical device with the above configuration, the protection characteristics of the light receiving surface of the light receiving element from moisture etc. are improved, and the reliability of the bump connection is improved by mounting from the light receiving surface side of the light receiving element by flip chip using bump. Another object of the present invention is to provide a composite optical device with improved device reliability and a method for manufacturing the same.

[0019]

To achieve the above object, a composite optical device according to the present invention is a composite optical device for irradiating an object to be illuminated with light and receiving its reflected light, wherein at least A substrate having a unit opening, a light emitting unit disposed on the substrate, and a light receiving unit disposed on the first surface of the substrate such that a light receiving surface faces the light receiving unit opening,
Arranged on the second surface of the substrate, the light emitted from the light emitting unit is emitted toward the irradiation target, and the reflected light from the irradiation target passes through the light receiving unit opening. And an optical member coupled to the light receiving section, at least the light receiving surface of the light receiving section is sealed with a resin.

The composite optical device of the present invention is preferably
The resin is transparent to at least light in a region where the light emitting unit emits light.

The composite optical device of the present invention is preferably
A joint between the electrode provided on the light receiving section and the electrode on the substrate is sealed with the resin. More preferably, the coefficient of thermal expansion of the resin is substantially the same as the coefficient of thermal expansion of an electrode provided in the light receiving section.

The composite optical device of the present invention is preferably
The resin is sealed from the inside of the opening for the light receiving portion to the light receiving portion with the resin. More preferably, on the second surface of the substrate, a light-transmissive member that closes the light-receiving unit opening is disposed, and the light-transmitting member is closed by the light-transmitting member. And the light receiving portion is sealed with the resin.

The composite optical device according to the present invention is preferably
The substrate further includes a light emitting unit opening, the light emitting unit is disposed on a second surface of the substrate, and the light emitted from the light emitting unit passes through the light emitting unit opening and passes through the light emitting unit opening. The light is emitted toward the irradiation target.

The composite optical device of the present invention is preferably
The substrate has a first substrate, and a second substrate for relaying the first substrate and the light receiving unit, and the light receiving unit opening communicates with the first substrate and the second substrate. It is provided. More preferably, a groove for injecting a resin into a gap between the second substrate and the light receiving unit is provided in the second substrate.

The composite optical device according to the present invention is an optical device having a configuration in which the light receiving surface of the light receiving element is opposed to the substrate to enable active alignment for highly accurate alignment. , And the protection properties from moisture etc. are improved,
Reliability has been improved. Furthermore, by employing a configuration in which the bonding portion (bump bonding portion) between the electrode provided on the light receiving portion and the electrode of the substrate is sealed with resin, the reliability of bump connection is improved, and further reliability is improved. Improvements are possible.

According to another aspect of the present invention, there is provided a method of manufacturing a composite optical device, comprising: a substrate having at least a light receiving portion opening; a light emitting portion disposed on the substrate; A light receiving unit disposed on the first surface of the substrate so as to face the internal opening, and a light emitting unit disposed on the second surface of the substrate and emitting light from the light emitting unit. A method of manufacturing a composite optical device, comprising: an optical member that emits light toward the target and reflects the reflected light from the irradiation target through the light receiving unit opening to couple to the light receiving unit.
Arranging an optical member on a second surface of the substrate, arranging a light receiving unit on the first surface of the substrate, arranging a light emitting unit on the substrate, Sealing the light receiving surface with a resin.

The method of manufacturing a composite optical device according to the present invention is as follows.
Preferably, in the step of arranging the light receiving unit on the first surface of the substrate, a temporary light emitting unit is arranged on the substrate, light is emitted from the temporary light emitting unit, and light is emitted from the irradiation target object. Arranging a light receiving unit on the first surface of the substrate so as to couple the reflected light to the light receiving unit through the light receiving unit opening, and further comprising removing the temporary light emitting unit; In the step of arranging the light emitting unit on the substrate, the light emitting unit emits light so that the reflected light from the object to be irradiated passes through the light receiving unit opening and is coupled to the light receiving unit. Place.

The method of manufacturing the composite optical device according to the present invention is as follows.
Preferably, in the step of sealing the light receiving surface with a resin,
The joint between the electrode provided on the light receiving section and the electrode on the substrate is simultaneously sealed. More preferably, a resin whose coefficient of thermal expansion is substantially the same as the coefficient of thermal expansion of an electrode provided in the light receiving portion is used as the resin.

The method for manufacturing a composite optical device according to the present invention is as follows.
Preferably, in the step of sealing the light receiving surface with a resin,
The resin is sealed from the inside of the opening for the light receiving portion to the light receiving portion with the resin.

The method of manufacturing the composite optical device according to the present invention is as follows.
Preferably, as the substrate, a first substrate, a second substrate for relaying the first substrate and the light receiving unit is used, and the light receiving unit opening is formed in the first substrate and the second substrate. A step of arranging the light receiving unit on the first surface of the substrate, the step of arranging the light receiving unit on the second substrate, and the step of arranging the upper light receiving unit on the second substrate. And disposing it on the first substrate. More preferably, before the step of arranging the light receiving section on the second substrate, a step of forming a groove for injecting a resin into a gap between the second substrate and the light receiving section in the second substrate. In the step of sealing the light receiving surface with a resin, a resin is injected from the groove into a gap between the second substrate and the light receiving section.

The method for manufacturing a composite optical device according to the present invention is as follows.
An optical member is disposed on the second surface of the substrate, a light receiving unit is disposed on the first surface of the substrate, a light emitting unit is disposed on the substrate, and at least a light receiving surface of the light receiving unit is sealed with a resin. For example, when the light receiving unit is installed on the first surface of the substrate, a temporary light emitting unit is installed on the substrate, light is emitted from the temporary light emitting unit, and reflected light from the object to be irradiated is transmitted to the light receiving unit opening. The light receiving unit is disposed on the first surface of the substrate so as to pass through the unit and be coupled to the light receiving unit.
Next, when the temporary light-emitting portion is removed and the light-emitting portion is installed on the substrate, the substrate is emitted while emitting light so that the reflected light from the irradiation target passes through the light-receiving portion opening and is coupled to the light-receiving portion. The light emitting part is installed in.

According to the method of manufacturing a composite optical device of the present invention, in the optical device having a structure in which the light receiving surface of the light receiving device is opposed to the substrate and which enables active alignment for highly accurate alignment, Since the light receiving surface is sealed with a resin, it can be manufactured with improved protection characteristics against moisture and the like and improved reliability. Furthermore, by simultaneously sealing the joint (bump joint) between the electrode provided on the light receiving section and the electrode of the substrate with resin,
The bump connection can be manufactured with improved reliability and further improved reliability. In particular, more precise alignment accuracy can be achieved by active alignment in which light is emitted using the provisional light emitting portion to take an optical axis, and alignment is performed while actually receiving light.

[0033]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1A is a schematic diagram showing a configuration of a composite optical device according to the present embodiment, and FIG. 1B is a layout diagram of a light receiving surface of a light receiving section (PDIC) used in the composite optical device. It is. For example, a submount 5 made of a silicon block having a semiconductor laser 51 mounted on one surface of a substrate 10 such as a package substrate made of resin or the like.
0 and a prism 52 having a reflection surface 52a are fixed. The light receiving section (PDIC) 43 has a PD light receiving surface 4.
A convex electrode (bump) (not shown) is provided on the second side, and PD
The IC 43 is mounted in a flip-chip manner with the PD light receiving surface 42 facing the relay substrate 40 side. The relay substrate 40 on which the PDIC 43 is mounted is connected and fixed to the substrate 10, and is externally connected by wiring (not shown) or the like. It is electrically connected to a terminal.

The other surface of the substrate 10 has a recess 10a.
Is provided, and the optical glass 13 is disposed at the bottom of the concave portion 10a. The diffraction grating 21 and the hologram 2 are placed on the other surface of the substrate 10 so as to cover the recess 10a.
3. A multi-lens 20 provided with a convex lens 22 and a concave lens 24 is mounted. On the upper surface of the multi-lens 20, for example, a spectral separation surface (31, 33, 34) such as a polarization separation surface for separating p-polarized light and s-polarized light or a total reflection surface, and 1/2
A multi-prism 30 made of a glass laminate having a wave plate 32 and the like is mounted. A cover 60 that protects the semiconductor laser 51, the PDIC 43, and the like is provided on the surface of the substrate 10 where the semiconductor laser 51 and the PDIC 43 are arranged.

In the above configuration, the substrate 10 is provided with the light emitting portion opening 11 and the light receiving portion opening 12. The optical glass 13 is arranged so as to cover the light receiving unit opening 12, and the relay board 40 is provided with an opening 41 communicating with the light receiving unit opening 12. Light-receiving unit opening 12 closed by optical glass 13
And from inside the opening 41 communicating with the PDIC 43
The light-receiving surface 42 is covered over the light-receiving surface 42, and the joint portion with the relay board 40 by a bump (not shown) is further covered to form a substantially light-transmitting sealing resin layer 44. .

The laser light LT emitted from the semiconductor laser 51 is reflected by the reflection surface 52a, passes through the light-emitting portion opening 11, passes through the diffraction grating 21, the convex lens 22, and the spectral surface 31 to form a composite optical device. And irradiates the object to be irradiated such as an optical disk with an external optical system.

The reflected light (return light) from the irradiation object is
The traveling direction is bent by the light splitting surface 31 and the half-wave plate 32
Proceed in the direction. Part of the light that reaches the surface of the half-wave plate 32 is reflected and part is transmitted. For example, a part of the s-polarized light component is reflected on the surface of the half-wave plate 32, the astigmatism is enlarged by the hologram 23 (equivalent to a cylindrical lens), the light passes through the optical glass 13, and the light receiving unit opening 1 is formed.
2 and the light-receiving surface 142 of the PDIC 143 through the sealing resin layer 44 provided in the opening 41 communicating therewith.
Incident on.

On the other hand, the component transmitted through the half-wave plate 42 has its polarization plane rotated and proceeds to the spectral plane (33, 34). For example, by rotating the polarization plane by 45 °, the p-polarized light component transmits 100% and the s-polarized light component
It is set so that 0% is reflected, and 100% of the p-polarized light component is reflected on the spectral surface 34. Spectral surface (3
The light reflected by (3, 34) passes through the convex lens 24, passes through the optical glass 13 in the same manner as described above, and
Then, the light passes through the sealing resin layer 44 provided in the opening 41 communicating with the light and enters the light receiving surface 42 of the PDIC 43.

The light receiving surface 42 of the PDIC 43 has a layout as shown in FIG.
2, a four-divided light receiving area 42a and a two-divided light receiving area (42
b, 42c) and a single light receiving area (42d, 42c).
e) are provided, and the component reflected on the surface of the half-wave plate 32 enters the four-divided light receiving area 42a and the two-divided light receiving areas (42b, 42c) as three spots. In addition, the component reflected on the spectral surface 33 enters the single light receiving area 42d as one spot. Further, the component reflected by the spectral surface 34 is a single light receiving area 42
e as one spot.

A light receiving signal of each light receiving area is generated on the PDIC 43, predetermined arithmetic processing is performed, and a function of detecting an RF signal, a focus error signal, a tracking error signal, and the like of the optical disk is contained in the PDIC 1 chip.

FIG. 2A is a plan view of the PDIC 43, FIG. 2B is a sectional view taken along line XX ′ in FIG. 2A, and FIG. This corresponds to a cross-sectional view at Y ′. The bump B provided on the light receiving surface 42 of the PDIC 43 is bonded to the wiring electrode W provided on the relay substrate 40, and the PDIC 43 is mounted on the relay substrate 40 in a flip-chip manner with the PD light receiving surface 42 facing the relay substrate 40 side. Have been. This bonding can be, for example, ultrasonic bonding using gold stud bumps or bonding using solder bumps. The relay board 40 on which the PDIC 43 is mounted as described above is connected and fixed to the board.

The substrate 10 is provided with a light-receiving opening 12, and the upper surface is closed by an optical glass 13. The relay board 40 is provided with an opening 41 so as to communicate with the light receiving section opening 12. The light receiving surface 42 is covered by the light receiving portion opening 12 closed by the optical glass 13 and the inside of the opening 41 communicating with the light receiving surface 42 of the PDIC 43. , A sealing resin layer 44 is formed. From the gap between the relay board 40 and the PDIC 43,
Light-receiving unit opening 12 closed by optical glass 13
And from inside the opening 41 communicating with the PDIC 43
In order to inject the resin over the light receiving surface 42, a groove 41a connected to the opening 41 is provided in the relay board 40 in advance. Thereby, even when the viscosity of the resin to be used is high, it is possible to supply the resin sufficiently to the required area.

The composite optical device according to the present embodiment has a structure in which the light receiving surface 42 of the PDIC 43 is opposed to the substrate 10 to enable active alignment for highly accurate alignment.
The light receiving surface 42 of 43 is sealed with a sealing resin layer 44,
The protection characteristics from moisture and the like are improved, and the reliability is improved. Further, since the bump bonding portion provided on the light receiving surface 42 of the PDIC 43 is sealed with a sealing resin layer, the reliability of the bump connection is improved, and the reliability can be further improved.

The resin of the sealing resin layer 44 preferably has substantially the same coefficient of thermal expansion as that of the bump connecting the PDIC 43 and the relay board 40. For example, when a gold bump is used, a gold material is used. One kind of filler to be blended in the resin to be used is selected so that the coefficient of thermal expansion matches, and the blending ratio is further adjusted to use a resin having a desired coefficient of thermal expansion. As a result, the stress applied during thermal expansion and contraction can be dispersed between the bump and the sealing resin layer, and the stress can be alleviated, and the bump can be prevented from deteriorating, such as cracks in the bump.

Next, a method of manufacturing the composite optical device according to this embodiment will be described. First, as shown in FIG. 3, a light emitting portion opening 1 is formed on a substrate 10 provided with a recess 10a.
1 and the light-receiving unit opening 12 are formed, and the optical glass 13 is arranged so as to cover the light-receiving unit opening 12 and fixed with an ultraviolet curing resin or the like.

Next, as shown in FIG.
A multi-lens 20 provided with a diffraction grating 21, a hologram 23, a convex lens 22, and a concave lens 24 is mounted on the substrate 10 so as to cover the area a. Next, multi-lens 2
The multi-prism 30 made of a glass laminate having, for example, a light-splitting surface (31, 33, 34) such as a polarization splitting surface or a total reflection surface for separating p-polarized light and s-polarized light, and a half-wave plate 32, etc. Attach. At this time, it is desirable to adjust the position of each optical member by using a marker provided on the substrate 10. As the adhesive, an ultraviolet curing resin or a thermosetting resin can be used. When a thermosetting resin is used, it is desirable that the resin be cured at a temperature lower than the heat resistance temperature of the optical component. More preferably, if the curing of the adhesive is sufficiently advanced, the accuracy of the subsequent position adjustment (alignment) of the light receiving element and the light emitting element can be improved.

Next, the PDIC 43 and the relay board 40, which are mounted and assembled in a separate process by the flip chip method, are used.
Is connected and fixed to the substrate 10. The position adjustment at this time can be performed by recognizing a marker or an outer shape provided on the substrate or the optical component, and is preferably performed by active alignment. As a result, the present invention can be applied to manufacture a composite optical device for a next-generation optical disk system using a high-NA objective lens and a short-wavelength light source in the blue to blue-violet region, which has attracted attention in recent years.

The above active alignment is performed as follows. That is, as shown in FIG. 5, on the surface of the substrate 10 opposite to the surface on which the multi-lens 20 and the multi-prism 30 are mounted, a temporary semiconductor laser LD mounted on the temporary submount SM and a temporary semiconductor laser LD having a reflection surface PRa. The prism PR is temporarily provided. The light LT is emitted from the temporary semiconductor laser LD, is reflected by the reflection surface PRa, passes through the light emitting unit opening 11, and is emitted from the multi-prism 30, and the temporary collimator lens CL and the objective lens are arranged on the optical axis. The OL is arranged, and the temporary optical disk DD is irradiated with light. The reflected light (return light) from the temporary optical disk DD is passed through the light receiving unit opening 12 of the substrate 10. At this time, a light spot equivalent to that in actual use is obtained.

The PDIC 43 and the relay board 40, which have been mounted and assembled in a separate process by flip chip mounting with the PD light receiving surface 42 facing the relay board 40, are positioned so that the above-mentioned spots can be optimally received. Connect and secure while adjusting. That is, for example, by installing a flow bar card on the relay board and taking out the photoelectric signal of the light receiving element, the PD
Handle the IC unit. As described above, the active alignment is realized by performing the handling and the flowing, and performing the alignment while receiving the light spot generated at the position to be mounted. The electrical and physical bonding of the PDIC 43 and the relay board 40 by the above-described flip chip method can be performed by, for example, an ultrasonic bonding method.

Next, as shown in FIG. 6A, after the temporary semiconductor laser LD and the temporary prism PR mounted on the temporary submount SM are temporarily removed, the dispenser D is removed.
In S, a resin is injected from a gap between the relay board 40 and the PDIC 43. At this time, as shown in FIG. 6B, which is an enlarged cross-sectional view of a main part of FIG. 6A, the injection is performed from a groove 41 a provided in advance in the relay substrate 40 so as to be connected to the opening 41.

In the above-described resin injection, the light receiving surface 4 of the PDIC 43 is removed from the light receiving portion opening 12 closed by the optical glass 13 and the opening 41 communicating therewith.
Inject to 2 so that no gap is formed. PDIC
43 by covering the light receiving surface 42 with resin.
Are completely shut off from the outside air, and the protection characteristics from moisture and the like are improved, so that the reliability can be improved. At this time, in order to ensure protection of the light receiving surface 42, it is desirable to inject resin into the opening 12 for the light receiving portion of the substrate 10 and the opening 41 of the relay substrate 40 without any gap. If there is a gap in the sealing resin layer 44, moisture may enter through the gap. If moisture exists in a narrow gap, a crack may be generated in the resin due to a large volume change due to vaporization and condensation, and furthermore, moisture may enter. Will forgive. When this penetration proceeds, the light may reach the light receiving surface in some cases, causing deterioration and deterioration of the light receiving portion, leading to deterioration of the photoelectric signal.

Further, by covering the bump bonding portion with the sealing resin layer, the stress applied during thermal expansion and contraction can be dispersed between the bump and the sealing resin layer. Although it is possible to prevent the bumps from deteriorating due to the occurrence of voids, it is desirable that no gaps (voids) occur near the bumps. This is because if a void exists, stress will be concentrated at that portion, and fatigue will easily occur.

Next, as shown in FIG.
A semiconductor laser 51 mounted on a submount 50 and a prism 52 having a reflection surface 52a are mounted on the surface on which the IC 43 is mounted. At this time, the light LT is emitted from the semiconductor laser 51, reflected by the reflection surface 52a, passed through the light emitting unit opening 11, and emitted from the multi-prism 30.
A temporary collimator lens CL and an objective lens OL are arranged on the optical axis, light is irradiated on the temporary optical disk DD, and reflected light (return light) from the temporary optical disk DD is transmitted to the light receiving portion opening 12 of the substrate 10. The submount 5 on which the semiconductor laser 51 is mounted is passed so that a light spot equivalent to that in actual use can be optimally received in each light receiving area on the light receiving section 42.
It is preferable that the position of the 0 and the prism 52 be adjusted and fixed.

Next, as shown in FIG. 8, a cover 60 for protecting the semiconductor laser 51 and the PDIC 43 and the like made of Fe or Cu is provided on the surface of the substrate 10 where the semiconductor laser 51 and the PDIC 43 are arranged. It is practically preferable to paint the inside of the protective cover 60 with a black resin because stray light will not be generated. Thus, the composite optical device shown in FIG. 1 can be manufactured.

According to the method of manufacturing the composite optical device of the present embodiment, the light receiving surface 4 of the PDIC 43 is
In the composite optical device having a configuration in which the active alignment that enables high-precision alignment can be performed with the configuration opposite to the configuration 2, the light receiving surface 42 of the PDIC 43 is sealed with a resin, so that the protection characteristic from moisture and the like is improved, and the reliability is improved. Can be manufactured with improved quality. Furthermore, by simultaneously sealing the bump bonding portion provided on the PDIC 43 with resin, the reliability of the bump connection can be improved, and the bump can be manufactured with further improved reliability. In particular, as described above, more precise alignment accuracy can be achieved by active alignment in which light is emitted using the provisional light emitting unit to take an optical axis, and alignment is performed while actually receiving light.

The present invention is not limited to the above embodiment. In each of the above embodiments, the sealing resin layer is formed from the opening for the light receiving unit closed by the optical glass and the opening communicating with the opening to the light receiving surface of the PDIC. May be formed so as to cover. In the embodiment, a groove is provided in the relay substrate. However, the relay substrate may have an opening shape other than the groove, or the groove or the opening shape may be provided on the substrate. Further, these groove or opening shapes are not necessarily required.

Further, first, a reinforcing resin is applied to the wiring portion or the bump of the light receiving element on the relay substrate, and a sealing resin is applied to the light receiving surface, and then connected to the relay substrate to receive the light receiving element unit (light receiving element). It can also be implemented by using a light-receiving element unit as a relay board on which elements are mounted). In addition, a reinforcing resin is applied to the wiring portion of the relay board or the bump of the light receiving element, and connected to the relay board to form a light receiving element unit (relay board on which the light receiving element is mounted). It can also be implemented by disposing a B-stage sealing resin, aligning and attaching the light receiving unit. In addition, various changes can be made without departing from the scope of the present invention.

[0059]

According to the composite optical device of the present invention, there is provided an optical device having a structure in which a light receiving surface of a light receiving element is opposed to a substrate to enable active alignment for highly accurate alignment. The surface is sealed with resin, and the protection characteristics from moisture and the like are improved, and the reliability is improved. Furthermore, by employing a configuration in which the bonding portion (bump bonding portion) between the electrode provided on the light receiving portion and the electrode of the substrate is sealed with resin, the reliability of bump connection is improved, and further reliability is improved. Improvements are possible.

According to the method of manufacturing the composite optical device of the present invention, in the optical device having a configuration in which the light receiving surface of the light receiving element is opposed to the substrate and which enables active alignment for highly accurate alignment, Since the light receiving surface is sealed with a resin, it can be manufactured with improved protection characteristics against moisture and the like and improved reliability. further,
By simultaneously sealing the joint (bump joint) between the electrode provided on the light receiving portion and the electrode on the substrate with resin, the reliability of bump connection can be improved, and the reliability can be further improved. In particular, more precise alignment accuracy can be achieved by active alignment in which light is emitted using the provisional light emitting portion to take an optical axis, and alignment is performed while actually receiving light.

[Brief description of the drawings]

FIG. 1A is a schematic diagram illustrating a configuration of a composite optical device according to an embodiment of the present invention, and FIG. 1B is a light receiving surface of a light receiving unit (PDIC) used in the composite optical device. FIG.

2A is a plan view of a PDIC portion in FIG. 1, FIG. 2B is a cross-sectional view taken along line XX ′ in FIG. 2A, and FIG. 2C is FIG. This corresponds to a cross-sectional view taken along line YY ′.

FIG. 3 is a cross-sectional view showing a process of manufacturing the composite optical device shown in FIG. 1 up to an optical glass bonding process in the manufacturing process.

FIG. 4 is a cross-sectional view showing up to the optical member mounting step, which is a continuation of FIG. 3;

FIG. 5 is a cross-sectional view showing up to a PDIC mounting step by active alignment, which is a continuation of FIG. 4;

FIGS. 6A and 6B are a cross-sectional view and a main part enlarged cross-sectional view, respectively, showing up to a resin injection step, which is a continuation of FIG.

FIG. 7 is a cross-sectional view showing up to the step of mounting a semiconductor laser by active alignment, which is a step subsequent to that of FIG. 6;

FIG. 8 is a cross-sectional view showing up to the step of attaching the protective cover, which is a step subsequent to FIG. 7;

FIG. 9A is a schematic diagram illustrating a configuration of an optical pickup device to which a composite optical device according to a conventional example is applied;
FIG. 9B shows a light receiving unit (PD) used in the above composite optical device.
FIG. 3 is a layout diagram of a light receiving surface of (IC).

FIG. 10 is a schematic configuration diagram of an optical device having a configuration in which a light receiving surface of a light receiving element and a substrate face each other according to a conventional example.

FIG. 11 is a schematic diagram showing a state of thermal expansion and expansion and contraction of a flip-chip bonded light receiving element and a substrate to which the element is attached, and a bump which mediates the light receiving element according to a conventional example.

[Explanation of symbols]

Reference numerals 10, 110: substrate, 10a, 111: concave portion, 11: light emitting portion opening, 12: light receiving portion opening, 13: optical glass, 20, 120: multi-lens, 21, 121: diffraction grating, 22, 122 ... convex lens, 23, 123 ... hologram, 24, 124, 125 ... concave lens, 30, 130
... Multi prism, 31, 33, 34, 131, 13
3, 134: spectral surface, 32, 132: 1/2 wavelength plate, 4
0: relay board, 41: opening, 41a: groove, 42, 14
2 ... light receiving surface, 42a, 142a ... 4 divided light receiving areas, 42
b, 42c, 142b, 142c... 2 divided light receiving areas, 4
2d, 42e, 142d, 142e ... single light receiving area,
43, 143: PDIC, 44: sealing resin layer, 50, 1
50: semiconductor laser, 51, 151: submount, 5
2 ... Prism, 52a, 150a ... Spectral surface, 60 ... Protective cover, 200 ... Substrate, 201 ... Prism, 201a ...
Spectral surface, 203: optical fiber, 204: optical fiber support, 205: light receiving surface, 206: light receiving element, B: bump,
CL: Collimator lens, D: Optical disk, DD: Temporary optical disk, DS: Dispenser, LD: Temporary semiconductor laser, LT: Light, OL: Objective lens, PD: Light receiving element, P
R: temporary prism, PRa: spectral surface, SM: temporary submount, Sub: substrate, T: terminal, W: wiring electrode.

Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G02B 5/32 G02B 5/32 G11B 7/125 G11B 7/125 A 7/22 7/22 (72) Inventor: Jun Yamauchi 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo F-term in Sony Corporation (reference) 2H042 CA00 CA06 CA14 CA17 2H049 AA02 AA04 AA12 AA14 AA26 AA50 AA57 AA64 CA01 CA05 CA09 CA15 CA20 5D119 AA38 BA01 CA09 JC06 LB04 LB06 NA

Claims (16)

[Claims] 1. A composite optical device for irradiating an object to be irradiated with light and receiving reflected light thereof, comprising: a substrate having at least a light receiving portion opening; a light emitting portion disposed on the substrate; A light receiving unit disposed on the first surface of the substrate such that a surface faces the inside of the light receiving unit opening; and a light emitting unit disposed on the second surface of the substrate and emitting light from the light emitting unit. An optical member that emits light toward the irradiation target object and couples the reflected light from the irradiation target object to the light receiving unit through the light receiving unit opening, and at least the light receiving of the light receiving unit A composite optical device whose surface is sealed with resin. 2. The composite optical device according to claim 1, wherein said resin is permeable to at least light in a region where said light emitting portion emits light. 3. The composite optical device according to claim 1, wherein a joint between the electrode provided on the light receiving section and the electrode on the substrate is sealed with the resin. 4. The composite optical device according to claim 3, wherein a thermal expansion coefficient of the resin is substantially the same as a thermal expansion coefficient of an electrode provided in the light receiving section. 5. The composite optical device according to claim 1, wherein the resin is sealed with the resin from inside the light receiving portion opening to the light receiving portion. 6. A light-transmissive member that closes the light-receiving unit opening is disposed on the second surface of the substrate, and the light-transmitting member is closed by the light-transmitting member. 6. The composite optical device according to claim 5, wherein the resin is sealed with the resin from the light receiving portion to the light receiving portion. 7. A light emitting unit opening is further provided on the substrate, the light emitting unit is arranged on a second surface of the substrate, and light emitted from the light emitting unit is transmitted to the light emitting unit opening. The composite optical device according to claim 1, wherein the light is emitted toward the object to be illuminated after passing through. 8. The substrate has a first substrate, and a second substrate for relaying the first substrate and the light receiving unit, wherein the light receiving unit opening is provided between the first substrate and the first substrate. The composite optical device according to claim 1, wherein the composite optical device is provided in communication with the two substrates. 9. The composite optical device according to claim 8, wherein a groove for injecting a resin into a gap between the second substrate and the light receiving section is provided in the second substrate. 10. A substrate having at least a light-receiving portion opening, a light-emitting portion disposed on the substrate, and a light-emitting portion disposed on the first surface of the substrate such that a light-receiving surface faces the light-receiving portion opening. And the light receiving unit is disposed on the second surface of the substrate,
An optical member that emits light emitted from the light emitting unit toward the irradiation target object, and couples reflected light from the irradiation target object to the light receiving unit through the light receiving unit opening. A method of manufacturing a composite optical device, comprising: arranging an optical member on a second surface of the substrate; arranging a light receiving unit on a first surface of the substrate; A method for manufacturing a composite optical device, comprising: a step of disposing; and a step of sealing at least the light receiving surface of the light receiving unit with a resin. 11. A step of arranging a light receiving portion on the first surface of the substrate, arranging a temporary light emitting portion on the substrate, emitting light from the temporary light emitting portion, and transmitting light from the object to be irradiated. Further comprising a step of disposing a light receiving section on the first surface of the substrate so as to couple the reflected light of the light passing through the light receiving section opening to the light receiving section, and removing the temporary light emitting section; In the step of arranging the light emitting unit on the substrate, light is emitted to the substrate while emitting light so that reflected light from the irradiation target passes through the light receiving unit opening and is coupled to the light receiving unit. The method for manufacturing a composite optical device according to claim 10, wherein the portions are arranged. 12. The manufacturing of the composite optical device according to claim 10, wherein in the step of sealing the light receiving surface with a resin, a joint portion between an electrode provided on the light receiving portion and an electrode of the substrate is simultaneously sealed. Method. 13. The method of manufacturing a composite optical device according to claim 12, wherein a resin having a coefficient of thermal expansion that is substantially the same as a coefficient of thermal expansion of an electrode provided in said light receiving portion is used as said resin. 14. The method of manufacturing a composite optical device according to claim 10, wherein in the step of sealing the light receiving surface with resin, the resin is sealed from inside the light receiving portion opening to the light receiving portion. 15. The method according to claim 15, wherein the substrate is a first substrate;
A second substrate for relaying the substrate and the light receiving unit, wherein the light receiving unit opening is provided so as to communicate with the first substrate and the second substrate, and on a first surface of the substrate; 11. The method according to claim 10, wherein the step of arranging the light receiving unit includes the step of arranging the light receiving unit on the second substrate and the step of arranging the upper light receiving unit on the first substrate on the second substrate on which the upper light receiving unit is arranged. A manufacturing method of the composite optical device according to the above. 16. A step of forming a groove in the second substrate for injecting a resin into a gap between the second substrate and the light receiving unit before the step of arranging the light receiving unit on the second substrate. The method according to claim 15, further comprising: in the step of sealing the light receiving surface with a resin, injecting a resin from the groove into a gap between the second substrate and the light receiving unit.