JP4887250B2 - Spectroscopic module - Google Patents

Description

  The present invention relates to a spectroscopic module that spectrally detects light.

As conventional spectral modules, for example, those described in Patent Documents 1 to 3 are known. In Patent Document 1, a support body that transmits light, an incident slit portion that allows light to enter the support body, a concave diffraction grating that splits and reflects light incident on the support body, and a concave diffraction grating are used. A spectroscopic module comprising a diode for detecting reflected light is described.
JP-A-4-294223 JP 2004-354176 A JP 2003-243444 A

  However, in the spectroscopic module described in Patent Document 1, when the incident slit portion and the diode are attached to the support, a relative positional relationship between the incident slit portion and the diode is shifted, and the reliability of the spectroscopic module is increased. May decrease.

  Therefore, the present invention has been made in view of such circumstances, and an object thereof is to provide a highly reliable spectral module.

To achieve the above object, a spectroscopic module according to the present invention includes a main body that transmits light, and a spectroscopic unit that splits light incident on the main body from a predetermined surface of the main body and reflects the light to a predetermined surface. And a light detecting element that detects light reflected and reflected by the spectroscopic part, and is electrically connected to a wiring formed on a predetermined surface side by face-down bonding, and a light detecting element And an underfill material that transmits light, and the light detection element has a light passage hole through which light traveling to the spectroscopic part passes, and the light detection element side The surface is formed with a reservoir for preventing the underfill material from entering the light passage hole so as to surround the light exit opening of the light passage hole, and the light traveling to the spectroscopic portion is formed on the predetermined surface. Travels to the first light passage section through which light passes and the light detection section A light absorption layer having a second light passage portion through which light passes is formed, an underfill material is filled between the light absorption layer and the light detection element, and the reservoir portion surrounds the light emission opening. The annular groove is formed, and the groove is formed so as to surround the first light passage portion when viewed from the center line direction of the light passage hole . The spectroscopic module according to the present invention includes a main body that transmits light, a spectroscopic unit that splits light incident on the main body from a predetermined surface of the main body and reflects the light to a predetermined surface, and a spectroscopic unit that performs spectroscopic analysis. A light detection unit that detects the reflected light, and is electrically connected to the wiring formed on a predetermined surface side by face-down bonding, and is filled in the main body side of the light detection element And an underfill material that transmits light, and the light detection element has a light passage hole through which light traveling to the spectroscopic portion passes, and the surface of the light detection element on the main body side is light A reservoir for preventing the underfill material from entering the light passage hole is formed so as to surround the light emission opening of the passage hole, and a first surface through which light traveling to the spectroscopic portion passes is formed on a predetermined surface. The second light passing through the light passing part and the light detecting part passes. A light absorption layer having a passage portion is formed, an underfill material is filled between the light absorption layer and the light detection element, and the reservoir portion is a recess formed to include a light output opening. Is characterized in that it is formed so as to include the first light passage portion when viewed from the center line direction of the light passage hole.

In the spectroscopic module, a light passage hole through which light traveling to the spectroscopic unit passes and a photodetection unit that detects light reflected and reflected by the spectroscopic unit are formed in the photodetection element. Therefore, it is possible to prevent a shift in the relative positional relationship between the light passage hole and the light detection unit. Further, the light detection element is electrically connected to the wiring formed on the predetermined surface side of the main body by face-down bonding, and an underfill material that transmits light is filled on the main body side of the light detection element. Therefore, the mechanical strength of the main body portion and the light detection element can be improved, and the refractive index matching of light traveling between the main body portion and the light detection element can be realized. Here, when the underfill material filled between the light detection element and the main body portion enters the light passage hole of the light detection element, the light passage is caused by the shape of the light incident side surface of the underfill material in the light passage hole. The light incident on the hole may be refracted or diffused. In the present invention, a reservoir is formed on the surface of the light detection element on the side of the main body so as to surround the light exit opening of the light passage hole. As a result, the underfill material is retained and retained in the reservoir portion to prevent the underfill material from entering the light passage hole, so that light is not refracted or diffused by the underfill material. It can be made incident. Therefore, according to this spectroscopic module, it becomes possible to improve reliability. In addition, a light absorption layer having a first light passage portion through which light traveling to the spectroscopic portion passes and a second light passage portion through which light traveling to the light detection portion passes is formed on the predetermined surface. Yes. In this case, generation of stray light is suppressed by the light absorption layer, and stray light is absorbed, so that the stray light can be prevented from entering the light detection portion of the light detection element. The reservoir may be an annular groove formed so as to surround the light output opening, or a recess formed so as to include the light output opening. In these cases, the reservoir can be formed with a simple structure. The groove is formed so as to surround the first light passage portion when viewed from the center line direction of the light passage hole, and the concave portion is formed by surrounding the first light passage portion when viewed from the center line direction of the light passage hole. It is formed to include. In these cases, the underfill material is retained and retained in the grooves or the recesses to prevent the underfill material from entering the first light passage portion of the light absorption layer. Therefore, the underfill material is refracted or diffused by the underfill material. Without making it possible, light can be incident on the main body.

  In the spectroscopic module according to the present invention, the wiring preferably has a light reflection preventing layer on a predetermined surface side. For example, even when the wiring is directly formed on a predetermined surface of the main body in order to improve the adhesion of the wiring to the main body and prevent the disconnection of the wiring, the light reflection preventing layer causes irregular reflection of stray light caused by the wiring. Etc. can be prevented.

  According to the present invention, reliability can be improved.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the same or an equivalent part, and the overlapping description is abbreviate | omitted.

[First Embodiment]
FIG. 1 is a plan view of the spectroscopic module according to the first embodiment of the present invention, and FIG. 2 is a cross-sectional view of the spectroscopic module of FIG. 1 along the line II-II. As shown in FIGS. 1 and 2, the spectroscopic module 1 splits light L1 incident on the main body 2 from the main body 2 that transmits light and the front surface (predetermined surface) 2a of the main body 2 to separate the front surface 2a. A spectroscopic unit 3 that reflects to the side, and a light detection element 4 that detects the light L2 that has been split and reflected by the spectroscopic unit 3. The spectroscopic module 1 measures the wavelength distribution of the light L1, the intensity of a specific wavelength component, etc. by splitting the light L1 into a plurality of light L2 by the spectroscopic unit 3 and detecting the light L2 by the light detecting element 4. It is.

Body 2, BK7, provided Pyrex, predetermined position on the rear surface of the light transmitting member 2 _1, and the light transmitting member 2 ₁ formed in a rectangular plate shape by light-transmissive glass such as quartz and a light transmitting member 2 _2. Light transmitting member 2 _2, the light transmitting member 2 ₁ and the same material, transparent resin, light-transmissive inorganic-organic hybrid materials, or a predetermined shape by light-transmissive low-melting glass for replica molding (here The hemispherical lens is formed into a shape in which a side surface is formed by cutting off two planes that are substantially orthogonal to the plane portion and substantially parallel to each other, and is reflected by the spectroscopic unit 3 L2 functions as a lens that forms an image on the light detection unit 41 of the light detection element 4. Light transmitting member 2 ₂ is its side is arranged so as to be substantially parallel to the longitudinal direction of the light transmitting member 2 _1, when formed of a light transmitting member 2 ₁ and the same material, by an optical resin or direct bonding It is bonded to the transparent member 2 _1.

Spectroscopic portion 3, the light transmitting member 2 ₂ of the outer surface which is formed in the diffraction layer 14, and a reflection type grating having a reflection layer 5 formed on the outer surface of the diffracting layer 14. Diffracting layer 14 is blazed gratings serrated cross section, a binary grating rectangular cross section, a holographic grating or the like of the sinusoidal cross-section, for example, a photosensitive resin is applied to the outer surface of the light transmitting member 2 _2, It is formed by UV-curing a photosensitive resin using a light-transmitting mold (grating mold) made of quartz or the like. The diffraction layer 14 becomes a more stable material when heated and cured after UV curing. The reflective layer 5 is in the form of a film, and is formed, for example, by evaporating Al, Au, or the like on the outer surface of the diffraction layer 14. The material of the diffractive layer 14 is not limited to a photosensitive resin, and may be a photosensitive glass, a photosensitive inorganic / organic hybrid material, or a resin, glass or inorganic / organic hybrid material that is deformed by heat. Also good.

The light detection element 4 is a one-dimensional array of long photodiodes arranged in a direction substantially orthogonal to the longitudinal direction thereof, and a light detection unit 41 that detects the light L2 that is split and reflected by the spectroscopic unit 3, and In the one-dimensional arrangement direction of the photodiodes, the light detection unit 41 is provided in parallel and has a light passage hole 42 through which the light L1 traveling to the spectroscopic unit 3 passes. Light passing hole 42 is a slit extending in a direction approximately orthogonal to the longitudinal direction of the light transmitting member 2 _1, it is formed by etching or the like in a state in which with respect to the optical detector 41 is positioned with high accuracy. Light detecting element 4, a one-dimensional arrangement direction of photodiodes longitudinal direction substantially coincides with and light detector 41 of the light transmitting member 2 ₁ is arranged so as to face the front surface 2a of the main body portion 2. The light detection element 4 is not limited to a photodiode array, and may be a C-MOS image sensor, a CCD image sensor, or the like.

The front plane 2a of the body portion 2 (i.e., the front surface of the light transmitting member _{2 1),} the single-layer film such as Al or Au, or Ti-Pt-Au, Ti- Ni-Au, a laminate film such as Cr-Au A wiring 9 is formed. Wire 9, the light transmitting member 2 ₁ a plurality of pad portions 9a arranged at the center portion, the light transmitting member 2 ₁ a longitudinal plurality of which are arranged at an end of the pad portions 9b, and the corresponding pad portions 9a and A plurality of connection portions 9c for connecting the pad portion 9b are provided. Further, the wiring 9 has a light reflection preventing layer 9 d made of a single layer film such as CrO or a laminated film such as Cr—CrO on the front surface 2 a side of the main body 2.

Further, a light absorption layer 6 is formed on the front surface 2 a of the main body 2 so as to expose the pad portions 9 a and 9 b of the wiring 9 and cover the connection portion 9 c of the wiring 9. The light absorption layer 6 has a light passage (first light passage) 6a through which the light L1 traveling to the spectroscopic section 3 passes and a light passage through which the light L2 traveling through the light detection section 41 of the light detection element 4 passes. Part (second light passage part) 6b. Light passing portion 6a is a slit extending in a direction approximately orthogonal to the longitudinal direction of the light transmitting member 2 _1. The light absorption layer 6 is patterned into a predetermined shape, and is integrally formed with CrO, a laminated film containing CrO, or a black resist.

In the pad portion 9 a exposed from the light absorption layer 6, the light passage hole 42 faces the light passage portion 6 a of the light absorption layer 6 and the light detection portion 41 faces the light passage portion 6 b of the light absorption layer 6. The external terminals of the light detection element 4 are electrically connected by face-down bonding via the bumps 15. Further, a flexible printed circuit board 11 for taking out an output signal of the light detection element 4 to the outside is electrically connected to the pad portion 9b exposed from the light absorption layer 6 by wire bonding. Then, the main body portion 2 side of the light detecting element 4 (in this case, between the light detecting element 4 and the light transmitting member 2 ₁ and the light-absorbing layer 6), the underfill material 12 which transmits at least light L2 is filled ing.

3 is a perspective view of the vicinity of the light passage hole of the light detection element of the spectral module of FIG. 1 as viewed from the main body side, and FIG. 4 is an enlarged cross-sectional view of the vicinity of the light passage hole of the spectral module of FIG. . As shown in FIGS. 3 and 4, the light passage hole 42 has a light incident side portion 42 ₁ that defines a light incident opening 42 a into which the light L 1 is incident, and a light exit that defines a light emitting opening 42 b through which the light L 1 is emitted. and a side 42 _2. Light exit side unit 42 ₂ is formed in a rectangular parallelepiped shape extending in a direction approximately orthogonal to the longitudinal direction of the light transmitting member 2 _1, the light entrance side unit 42 _1, the opposite from the light exit side unit 42 ₂ It is formed in a square frustum shape that widens toward the side. That is, the light passage hole 42 is formed such that the light incident opening 42a includes the light emitting opening 42b when viewed from the center line CL direction.

  A reservoir 43 is formed on the rear surface 4a of the photodetecting element 4 on the main body 2 side so as to surround the light exit opening 42b. The reservoir 43 includes a rectangular annular groove 44 formed so as to surround the light emitting opening 42b. When viewed from the center line CL direction of the light passage hole 42, the area of the region surrounded by the groove 44 is larger than the area of the light passage portion 6 a of the light absorption layer 6.

In the spectroscopic module 1 configured as described above, the light L1 passes from the front surface 2a of the main body 2 to the main body 2 through the light passage hole 42 of the light detection element 4 and the light passage 6a of the light absorption layer 6. Incident light travels through the light transmitting members 2 ₁ and 2 ₂ and reaches the spectroscopic unit 3. The light L1 reaching the spectroscopic unit 3 is split into a plurality of lights L2 by the spectroscopic unit 3. Dispersed light L2 is reflected on the front surface 2a of the main body portion 2 traveling through the light transmitting member 2 _2, 2 ₁ by the spectroscopic portion 3, the light detecting element through the light-passing portion 6b of the light absorbing layer 6 4 light detectors 41 are reached. The light L2 that has reached the light detection unit 41 is detected by the light detection element 4.

  As described above, in the spectroscopic module 1, the light passage hole 42 through which the light L1 traveling to the spectroscopic unit 3 passes, and the light detection unit 41 that detects the light L2 that has been split and reflected by the spectroscopic unit 3, The light detection elements 4 are formed in a state of being positioned with high accuracy. Therefore, installation of another member for forming the light passage hole 42 and positioning between the light passage hole 42 and the light detection unit 41 are not required (that is, the spectroscopic unit 3 is positioned with respect to the light detection element 4). Just do it). Therefore, the spectral module 1 can be reduced in size and cost.

  In the spectroscopic module 1, the light detection element 4 is electrically connected to the wiring 9 formed on the front surface 2 a side of the main body 2 by face-down bonding, and transmits the light L 1 and L 2. Is filled on the main body 2 side of the light detection element 4. In this way, by configuring the light detection element 4 to be electrically connected to the outside via the wiring 9 formed in the main body 2, for example, the flexible printed circuit board 11 and the light detection element 4 are directly (machined). As in the case of connection, the force applied to the flexible printed circuit board 41 during use of the spectroscopic module 1 is not directly transmitted to the light detection element 4, so that a load such as stress is generated on the light detection element 4. This can be prevented, and the photodetecting element 4 can be downsized. Further, by filling the underfill material 12 on the main body 2 side of the light detection element 4, the mechanical strength of the main body 2 and the light detection element 4 can be improved, and the main body 2 and the light detection element 4. Refractive index matching can be realized in all of the paths through which the light beams L1 and L2 traveling between are propagated.

  In the spectroscopic module 1, a groove 44 (a reservoir 43) is formed on the surface 4 a of the light detection element 4 so as to surround the light emission opening 42 b of the light passage hole 42. As a result, the underfill material 12 is stored and retained in the groove 44 (reservoir 43), and the underfill material 12 is prevented from entering the light passage hole 42. Therefore, the underfill material 12 is refracted or diffused by the underfill material 12. It is possible to make the light incident on the main body 2 without doing so.

  In the spectroscopic module 1, the wiring 9 has a light reflection preventing layer 9 d on the front surface 2 a side of the main body 2. Accordingly, even if the wiring 9 is directly formed on the front surface 2a of the main body 2 in order to improve the adhesion of the wiring 9 to the main body 2 and prevent disconnection of the wiring 9, the light reflection preventing layer 9d causes the wiring 9 to It is possible to prevent stray light from being irregularly reflected due to the phenomenon.

  Further, the spectroscopic module 1 has a light absorption layer having a light passing portion 6a through which the light L1 traveling to the spectroscopic portion 3 passes and a light passing portion 6b through which the light L2 traveling to the light detecting portion 41 of the light detecting element 4 passes. 6 is formed on the front surface 2 a of the main body 2. The light absorption layer 6 suppresses the generation of stray light and absorbs the stray light, so that the stray light can be prevented from entering the light detection unit 41.

  Further, since the reservoir 43 is a groove 44 formed so as to surround the light emitting opening 42b, the reservoir 43 can be formed with a simple structure.

  Further, in the spectroscopic module 1, the groove 44 is formed so as to surround the light passage portion 6 a when viewed from the direction of the center line CL of the light passage hole 42. As a result, the underfill material 12 is retained and retained in the groove 44 and the underfill material 12 is prevented from entering the light passage portion 6a of the light absorption layer 6, so that it is refracted or diffused by the underfill material 12. It is possible to make the light incident on the main body 2 without doing so.

[Second Embodiment]
The spectroscopic module 1 according to the second embodiment is mainly different from the spectroscopic module 1 according to the first embodiment in the configuration of the reservoir 43 provided on the surface 4 a side of the light detection element 4.

FIG. 5 is a perspective view of the photodetecting element of the spectroscopic module according to the second embodiment viewed from the main body side, and FIG. 6 is an enlarged cross section near the light passage hole of the spectroscopic module according to the second embodiment. FIG. In the photodetecting element 4 of the spectroscopic module 1 according to the second embodiment, as shown in FIGS. 5 and 6, the reservoir 43 formed on the surface 4 a side of the photodetecting element 4 is the light transmitting member 2 _1. The rectangular concave portion 45 is formed so as to extend in a direction substantially orthogonal to the longitudinal direction of the light source and to include the light emission opening 42b. When viewed from the center line CL direction of the light passage hole 42, the area surrounded by the recess 45 is larger than the area of the light passage portion 6a.

  As described above, in the spectroscopic module 1, the concave portion 45 is formed on the surface 4 a of the light detection element 4 as the reservoir 43 so as to include the light emission opening 42 b of the light passage hole 42. Thereby, the reservoir 43 can be formed with a simple structure.

  In the spectroscopic module 1, the recess 45 is formed so as to include the light passage portion 6 a when viewed from the direction of the center line CL of the light passage hole 42. As a result, the underfill material 12 is retained and retained in the concave portion 45 to prevent the underfill material 12 from entering the light passage portion 6a of the light absorption layer 6, so that the underfill material 12 is refracted or diffused by the underfill material 12. It is possible to make the light incident on the main body 2 without doing so.

  The present invention is not limited to the embodiment described above.

  For example, the light absorption layer 6 may be formed on the front surface 2 a of the main body 2 and the wiring 9 may be formed on the front surface of the light absorption layer 6. In this case, stray light irregular reflection caused by the wiring 9 can be prevented without providing the light reflection preventing layer 9d on the wiring 9.

Further, the light transmitting member 2 ₂ and the diffraction layer 14 that functions as a lens, may be integrally formed by a light transmitting low melting glass for replica molding. In this case, it is possible to prevent it is possible to simplify the manufacturing process, from the deviation in the relative positional relationship between the light transmitting member 2 ₂ and the diffraction layer 14 occurs.

1 is a plan view of a spectroscopic module according to a first embodiment of the present invention. It is sectional drawing along the II-II line of the spectroscopy module of FIG. It is the perspective view which looked at the photon detection element of the spectroscopy module 1 of FIG. 1 from the main body side. It is an expanded sectional view of the vicinity of the light passage hole of the spectroscopic module of FIG. It is the perspective view which looked at the photon detection element of the spectroscopy module concerning a 2nd embodiment from the main-body part side. It is an expanded sectional view near the light passage hole of the spectroscopic module concerning a 2nd embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Spectroscopic module, 2 ... Main-body part, 2a ... Front surface (predetermined surface), 3 ... Spectroscopic part, 4 ... Photodetection element, 4a ... Rear surface (surface by the side of a main-body part), 6 ... Light absorption layer, 6a ... Light Passing portion (first light passing portion), 6b ... light passing portion (second light passing portion), 9 ... wiring, 9d ... light reflection preventing layer, 12 ... underfill material, 16 ... light transmitting plate, 41 ... Light detection part 42 ... light passage hole 42b ... light emission opening 43 ... reservoir part 44 ... groove 45 ... recessed part CL ... center line.

Claims (3)

A main body that transmits light;
A spectroscopic unit that splits light incident on the main body from a predetermined surface of the main body and reflects the light to the predetermined surface;
A light detecting element that detects light reflected and reflected by the spectroscopic part, and is electrically connected to the wiring formed on the predetermined surface side by face-down bonding;
An underfill material that fills the body of the photodetecting element and transmits light;
The light detection element has a light passage hole through which light traveling to the spectroscopic unit passes,
A reservoir for preventing the underfill material from entering the light passage hole is formed on the surface of the light detection element on the body portion side so as to surround the light emission opening of the light passage hole .
A light absorption layer is formed on the predetermined surface. The light absorption layer includes a first light passage section through which light traveling to the spectroscopic section passes and a second light passage section through which light traveling to the light detection section passes. ,
Between the light absorption layer and the light detection element, the underfill material is filled,
The reservoir is an annular groove formed so as to surround the light exit opening,
The spectroscopic module according to claim 1, wherein the groove is formed so as to surround the first light passage portion when viewed from a center line direction of the light passage hole . A main body that transmits light;
A spectroscopic unit that splits light incident on the main body from a predetermined surface of the main body and reflects the light to the predetermined surface;
A light detecting element that detects light reflected and reflected by the spectroscopic part, and is electrically connected to the wiring formed on the predetermined surface side by face-down bonding;
An underfill material that fills the body of the photodetecting element and transmits light;
The light detection element has a light passage hole through which light traveling to the spectroscopic unit passes,
A reservoir for preventing the underfill material from entering the light passage hole is formed on the surface of the light detection element on the body portion side so as to surround the light emission opening of the light passage hole.
A light absorption layer is formed on the predetermined surface. The light absorption layer includes a first light passage section through which light traveling to the spectroscopic section passes and a second light passage section through which light traveling to the light detection section passes. ,
Between the light absorption layer and the light detection element, the underfill material is filled,
The reservoir is a recess formed to include the light exit opening;
The spectroscopic module , wherein the concave portion is formed so as to include the first light passage portion when viewed from a center line direction of the light passage hole . The spectroscopic module according to claim 1 , wherein the wiring has a light reflection preventing layer on the predetermined surface side.

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