JP2003204053A - Imaging module and its manufacturing method and digital camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify the step of aligning a focusing lens with a semiconductor chip by facilitating sealing of a photodetector. <P>SOLUTION: The imaging module comprises the semiconductor chip 104 having a photodetector array, and optical elements 101, 102 for guiding a light onto the array. The module further comprises a focusing unit 100 and a shielding layer 103 in the photodetector, so that an ultraviolet curable resin 105 formed at a position avoiding the shielding layer to a light incident direction between the chip and the optical element and the optical element is fixed to the chip via the resin. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup module and an image pickup device, and more particularly to a structure of an image pickup module in which an image forming optical system and a semiconductor chip are integrated.

[0002]

2. Description of the Related Art Conventionally, in a downsized image pickup module, an imaging lens and a semiconductor chip are integrated.

57 (A) and 57 (B) show an example of a miniaturized image pickup module, which is disclosed in Japanese Patent Laid-Open No. 09-027.
It shows a configuration similar to the distance measuring module described in Japanese Patent No. 606. In FIG. 57, 51 is a lens member, 50 is a semiconductor chip 54 on the lower surface of the glass substrate 53.
1 shows the structure of a COG (chip on glass) to which is attached. The lens member 51 is made of plastic or glass and includes lenses 51L and 51R that form two images in order to measure the distance to the object by the principle of triangulation. Further, the semiconductor chip 54 is provided with light receiving element portions 57L and 57R formed of a one-dimensional light receiving element array, and the object light passing through the lens 51L passes through the light receiving element portion 57L and the lens 51R passes through the light receiving element portion 57R. The object light is imaged.

FIG. 57 shows the upper surface of the glass substrate 53.
A light-shielding layer 55 having a pattern shown in (B) is printed to form a diaphragm, while a light-shielding / conductive member 56 is formed on the lower surface of the glass substrate 53 as a connection terminal with the semiconductor chip 54 and an external terminal. .

By adopting such a COG structure, a sensor package made of plastic or the like is unnecessary, and since a lens barrel is not required by integrating a lens, the manufacturing cost can be kept relatively low.

On the other hand, when the semiconductor chip 1 is packaged by wire bonding, the package becomes thicker and larger than the COG structure, and the mounting cost becomes high. Therefore, in order to reduce the size, there is a technique of sealing the light receiving element portion with a thermal ultraviolet curing resin. Fig. 58
FIG. 58 (E) and FIG. 59 (F) to FIG. 59 from (A).
(H) is a schematic sectional view showing a manufacturing process of an image pickup module (semiconductor device) disclosed in Japanese Patent Laid-Open No. 11-121653. FIG. 58A shows the semiconductor chip 1.
58 (B) is a top view of the semiconductor chip 1 shown in FIG. 58 (A) as seen from below.

To explain the manufacturing process in detail, first, the semiconductor chip 1 is prepared. The semiconductor chip 1 has a plurality of electrode pads (bonding pads) 2 near the outer periphery,
A microlens group 3 in which microlenses are densely arranged is provided near the center. The electrode pad 2 is formed of, for example, Al or Cr. The microlens group 3 is made of, for example, a synthetic resin. The semiconductor chip 1 includes, for example, a photoelectric sensor and C
It is a solid-state image sensor including a CD. The photoelectric sensor is, for example, a photodiode, and converts light received from the outside through the microlens group 3 into an electric signal. The electric signal is transferred by the CCD to generate an image signal.

In the step of forming the microlens group 3, first, a synthetic resin layer is formed, and a resist film having a predetermined pattern is formed thereon. Next, heating is performed to round the corners of the resist film to form microlenses. The semiconductor chip is manufactured by a known method. In order to obtain the light condensing function of the microlens group 3, when mounting the semiconductor chip on the glass substrate, it is necessary to form a hollow portion with the glass substrate at a position where the light receiving element of the semiconductor chip is present.

Next, the semiconductor chip 1 and the glass substrate are
An example is shown in which the gold ball and the conductive resin are connected.
As shown in FIG. 58C, the gold balls 4 are arranged on the electrode pads 2 of the semiconductor chip 1 by the ball bonding device. The gold ball has a size of 30 to 80 μm, for example.

Next, as shown in FIG. 58D, the conductive resin 5 is attached to the lower portion of the gold ball 4. For example, the conductive resin 5 can be attached to the gold balls 4 using a pallet having the entire surface coated with the conductive resin 5. The conductive resin 5 is, for example, an epoxy resin in which silver particles are dispersed (silver paste).

Next, as shown in FIG. 58E, the electrodes 6 of the transparent substrate (eg, glass substrate) 7 are brought into contact with the corresponding electrode pads 2 of the semiconductor chip 1 with the gold balls 4 sandwiched therebetween. To heat. By heating, the conductive resin 5 is cured, and the electrode 6 of the transparent substrate 7 and the electrode pad 2 of the semiconductor chip 1 are electrically connected by a predetermined wiring. The heating conditions are, for example, a heating temperature of 100 to 200 ° C. and a heating time of 30 minutes. The electrode 6 is, for example, Cr or Ni, is formed on the transparent substrate 7 by vapor deposition, plating or sputtering, and is patterned by, for example, photolithography and etching.

The material of the transparent substrate 7 is a transparent insulating material, such as glass, polycarbonate, polyester, or Kapton, and glass is particularly preferable. Hereinafter, a case where a glass substrate is used as the transparent substrate 7 will be described. As shown in FIG. 59 (F), the light shielding mask 14 is arranged so as to face the lower surface of the glass substrate 7, and electromagnetic waves (for example, ultraviolet rays) 15 are irradiated from below the glass substrate 7. The light-shielding mask 14 has a predetermined pattern and allows the electromagnetic wave 15 to pass only through the region 13 including the microlens group 3. The electromagnetic wave 15 is, for example, ultraviolet light, infrared light, visible light, or X
Lines and the like are preferable, and ultraviolet rays are particularly preferable. Below, electromagnetic wave 15
The case where ultraviolet rays are used as will be described. While irradiating with the ultraviolet rays 15, the insulating thermo-ultraviolet curing resin 12 is supplied from the capillary 11 between the semiconductor chip 1 and the glass substrate 7 at room temperature, for example.

The thermal ultraviolet curing resin 12 is used for the semiconductor chip 1
The space between the glass substrate 7 and the glass substrate 7 enters from the end toward the central portion due to the capillary phenomenon.

The thermal ultraviolet curing resin 12 is a resin which is cured by ultraviolet rays or heat. Thermal UV curing resin 1
2 flows in without being cured in the region where the ultraviolet ray 15 is not irradiated, and is cured in the region where the ultraviolet ray 15 is irradiated. As a result, the thermal ultraviolet curable resin 1 at the boundary between the region 13 irradiated with ultraviolet rays and the region not irradiated with ultraviolet rays 1
2a hardens.

Once the thermal UV-curable resin 12a at the boundary is cured, the thermal UV-curable resin 12 will not flow into the UV irradiation region 13 any more. However, since it takes some time for the thermal ultraviolet curing resin 12a to cure, the thermal ultraviolet curing resin 12a slightly flows into the ultraviolet irradiation region 13 and then is cured.

The electrode pad 2 of the semiconductor chip 1 and the electrode 6 of the glass substrate 7 are connected via a gold ball 4.
The thermal ultraviolet curable resin 12 is used for the electrode pad 2 and the gold ball 4.
, And a part of the electrode 6.

When the thermo-ultraviolet curable resin 12 sufficiently enters between the semiconductor chip 1 and the glass substrate 7, the supply of the thermo-ultraviolet curable resin 12 from the capillary 11 is stopped.

The ultraviolet irradiation area 13 shown in FIG. 59 (F).
Is a rectangular region when projected from above, for example, as shown in FIG. However, the central portion of the rectangle may not be irradiated with ultraviolet rays. A hollow portion 13 is provided between the glass substrate 7 and the microlens group 3 of the semiconductor chip 1.
Is formed. The thermal ultraviolet curing resin 12 is formed so as to surround the hollow portion 13.

However, in this state, only the thermal ultraviolet curing resin 12a at the boundary portion is cured, and the portion of the thermal ultraviolet curing resin 12 not irradiated with the ultraviolet rays 15 is not cured.

Next, as shown in FIG. 59 (G), heat 16 is applied to cure the portion of the thermal ultraviolet curable resin 12 which is not irradiated with the ultraviolet rays 15. The heating condition is, for example, 8
5 hours at 0 ° C. The entire region of the thermal ultraviolet curable resin 12 between the semiconductor chip 1 and the glass substrate 7 is completely cured by heating. It can be said that the ultraviolet curing shown in FIG. 59 (F) is temporary curing, and the thermal curing shown in FIG. 59 (G) is main curing. With the above, the COG is completed.

FIG. 59G shows 58G- in FIG. 59H.
FIG. 58 is a schematic cross-sectional view taken along the line 58G. The thermal ultraviolet curing resin 12 is formed so as to surround the hollow portion 13. The gold ball 4 is composed of the electrode pad 2 of the semiconductor chip 1 and the glass substrate 7.
And the electrode 6 are electrically and mechanically connected. However, since the gold ball 4 has a weak mechanical connection strength, the thermal ultraviolet curing resin 12 reinforces the mechanical connection between the semiconductor chip 1 and the glass substrate 7. Since the thermal ultraviolet curing resin 12 is an insulating member, it does not change the electrical connection between the semiconductor chip 1 and the glass substrate 7.

Through the above steps, the light receiving element portion including the microlens is sealed with the transparent substrate and the thermo-ultraviolet curable resin, and it becomes possible to prevent dust from entering and deterioration due to humidity in the air. Further, generally, this microlens is composed of a convex surface facing the direction of incidence of light, and refracts light at the interface between air and resin or air and glass to collect incident light on a light receiving element smaller than the microlens. Work. Therefore, the light receiving efficiency of the sensor can be improved.

Further, a method for mass-producing the above-mentioned image pickup module is also disclosed in the publication.

FIG. 60 shows a transparent substrate (eg glass substrate).
7 is a top view of FIG. The glass substrate 7 is, for example, 150 m long
m, width 150 mm, thickness 1 mm. This glass substrate 7 has a region of 10 × 10 blocks. One block has a length of 15 mm, a width of 15 mm, and a thickness of 1 mm.

One semiconductor chip 1 is mounted on each block, and a total of 10 × 10 semiconductor chips 1 are mounted on the glass substrate 7. One semiconductor chip 1 has a length of 8 mm and a width of 6 mm, for example.

Next, a resin is supplied between the semiconductor chip 1 and the glass substrate 7 and temporarily fixed by ultraviolet rays or the like. Then, put the glass substrate 7 in an oven at 150 ° C. for 30 minutes,
The resin is cured and the semiconductor chip 1 is fixed to the glass substrate 7. The glass substrate 7 is cut by a cutter along the block boundary line 43 to separate each imaging module. And above 1
00 imaging modules are completed.

FIG. 61 is a perspective view of an image pickup module using a conventional gradient index lens. The light receiving element section 60 is formed on a semiconductor chip 61 such as a silicon substrate. The plurality of lens units 62 are provided in an array on the same surface and are composed of gradient index lenses 62A to 62L. The plurality of lens portions 62 are arranged on the image pickup surface 60A of the light receiving element portion 60, and the emission end faces of the plurality of lens portions 62 are the image pickup surface 6A.
The passing light that is in contact with 0A and has passed through the plurality of lens units 62 is supplied to the imaging surface 60A. At this time, the gradient index lenses 62A to 62L are configured to have different focal lengths or focus positions by changing the respective refractive index distributions, and it is possible to simultaneously generate image data corresponding to a plurality of focus positions of the subject. Is.

By adopting such a structure as in the case of the COG structure, a sensor package made of plastic or the like is unnecessary, and since a lens barrel is not required by integrating the lens, the manufacturing cost is reduced. It can be kept relatively low.

[0029]

However, when the lens-integrated image pickup module is manufactured by using the above-mentioned conventional technique, there are the following problems.

(Technical Problem 1) FIGS. 57 (A) and 57
With the configurations of (B) and FIG. 61, it is possible to obtain an image pickup module that does not require a sensor package, but since the light receiving element portion is not sealed, a microlens or a filter due to dust ingress or humidity in the air can be obtained. It is difficult to prevent layer deterioration. Moreover, from FIG. 58 (A) to FIG.
(E) and FIG. 57 (A) shows the sealing technique using the thermal ultraviolet curing resin described with reference to FIGS. 59 (F) to 59 (H).
57 and the structure shown in FIG. 57B, the light-shielding layer 5
No. 5 could not be used because it covers the entire surface of the semiconductor chip and blocks light from the front of the semiconductor chip.

Further, in the step of joining the image forming lens and the semiconductor chip, active assembly of the image forming lens and the semiconductor chip is indispensable, which requires a lot of adjustment man-hours.

Further, even if a large number of image forming lenses are integrated on the glass substrate 7 shown in FIG. 60, precise alignment with the image forming lens corresponding to each semiconductor chip is required, and many adjustments are required. There is no change in the number of man-hours required.

It is necessary to form an ITO film for connection with an external electric circuit on the glass substrate, which is disadvantageous in cost.

(Technical Problem 2) Since the image pickup module shown in FIG. 57 (A) is composed of only one lens 51, its optical performance is low for use as an optical system for image pickup. In this case, it is conceivable to increase the number of lenses and the number of surfaces having a lens action, but in such a case, the image pickup optical system becomes large. On the other hand, the same problem occurs when the imaging optical system is composed of a gradient index lens.

Therefore, an object of the present invention is to provide an image pickup module integrated with an image forming lens in which the light receiving element portion can be easily sealed.

Another object of the present invention is to provide an image pickup module integrated with an image forming lens, which simplifies the step of aligning the image forming lens and the semiconductor chip, and as a result, is inexpensive and has high performance. .

Another object of the present invention is to provide a lens-integrated image pickup module having improved image pickup optical performance and an image pickup apparatus provided with the image pickup module.

[0038]

In order to solve the above technical problem 1, an image pickup module of the present invention comprises a semiconductor chip having a light receiving element array, and an optical element for guiding light onto the light receiving element array. In the imaging module having, the optical element includes an image forming section formed on a light-transmissive plate and a light shielding layer having an opening for narrowing an image forming light beam.
Further, the optical element is fixed to the semiconductor chip via an adhesive layer formed between the semiconductor chip and the optical element at least at a position avoiding the light shielding layer.

In order to solve the above technical problem 2,
The image pickup module of the present invention is an image pickup module having an optical element for guiding incident light onto a light receiving element array provided on a semiconductor chip, wherein the optical element is a first compound eye lens section and a second compound eye lens. And the second compound-eye lens part is provided corresponding to the first compound-eye lens part.

Further, the image pickup module of the present invention is an image pickup module having a semiconductor chip having a light receiving element array and an optical element for guiding light onto the light receiving element array, wherein the optical element is a light transmitting plate. An image forming portion formed on the cylindrical body, a light shielding layer having an opening for narrowing an image forming light beam, a first compound eye lens section, and a second compound eye lens section corresponding to the first compound eye lens section. The optical element is fixed to the semiconductor chip via an adhesive formed between the semiconductor chip and the optical element and at a position avoiding the light shielding layer in the light incident direction. It is characterized by

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

(First Embodiment) FIG. 1A is a schematic sectional view of an image pickup module showing the structure of the first embodiment of the present invention.

FIG. 1B is a schematic sectional view showing another structure of the image pickup module of the present invention.

In FIG. 1, 101 is an upper substrate having a convex lens 100 as an image forming section, 102 is a lower substrate,
Reference numeral 103 denotes a diaphragm light-shielding layer in which a light-shielding member is formed on the upper surface of the lower substrate 102 by, for example, offset printing, 104 denotes a semiconductor chip in which pixels (not shown) including light receiving elements are two-dimensionally formed, and 105 denotes a lower substrate. 102 and semiconductor chip 1
An adhesive agent for bonding 04, a planar resin portion 180 formed around the convex lens 100, a diaphragm opening 200 in which the diaphragm light-shielding layer 103 is not formed on the upper surface of the lower substrate 102, and 107 in the upper substrate 101 and the lower substrate 102. Is an optical element formed by bonding together.

The flat resin portion 1 shown in FIG.
Reference numeral 80 prevents the surface accuracy of the convex lens 100 from being lowered around the lens. Further, the flat resin portion 180 does not reach the end surface of the upper substrate 101, and the dicing blade does not cut the flat resin portion 180 in the dicing process described later. Therefore, the resin does not melt due to frictional heat with the dicing blade, becomes fine fragments, or becomes carbon particles and adheres to the lens surface, and does not deteriorate the quality of the imaging module.

In this embodiment, the image pickup module of FIG. 1A will be described as an example. The optical element 107 does not form an interface between the air and the upper substrate 101 or the lower substrate 102 by bonding the upper substrate 101 and the lower substrate 102 with a light-transmissive adhesive without any gaps. It is more preferable because it prevents ghosts from occurring.

The upper substrate 101 and the lower substrate 102 are made of glass or transparent resin, and when made of glass, they are made by a glass molding method, and when made of transparent resin, they are made by injection molding or compression molding. Also,
The upper substrate 101 may have a structure in which a resin lens portion is added to the flat glass substrate by a replica manufacturing method. Lower substrate 1
02 is a semiconductor chip 1 especially when borosilicate glass is used.
The difference in linear expansion from that of No. 04 is small, which is preferable in terms of stability against temperature change. In addition, in order to prevent the occurrence of defects due to α rays of the semiconductor chip 104, the upper substrate 101 and the lower substrate 102
In both cases, it is preferable to use optical glass having a low α-ray surface density, and it is particularly desirable that the lower substrate 102 near the semiconductor chip 104 has a lower α-ray surface density than the upper substrate 101.

FIG. 2A shows the optical element 1 of the image pickup module.
07 is a top view showing an upper substrate 101 which is an element constituting the optical element 07, FIG. 2B is a top view showing a lower substrate 102 which is an element constituting an optical element 107, and FIG. 2C is a semiconductor chip. 3 is a schematic cross-sectional view of the semiconductor chip 104 at the position of line 3-3 shown in FIG. 2 (C). FIG. 4 is a schematic sectional view showing the incident direction of light with respect to the image pickup module of the present invention.

In FIG. 2, reference numeral 1021 denotes the diaphragm light-shielding layer 10.
3, a transparent region except for the aperture opening 200 in the peripheral portion,
Is a penetrating metal body that penetrates the semiconductor chip 104 and electrically connects a front surface electrode on one main surface of the semiconductor chip 104 and a back surface electrode on the other main surface.

The image pickup module shown in FIG. 1 includes an optical element 10.
7 and the semiconductor chip 104 are integrated so that a sensor package and a lens barrel are not required.

Object light incident on the optical element 107 from above in FIG. 1 forms an object image on the semiconductor chip 104.

The optical element 107 is a light-transmissive plate-like body formed by bonding the upper substrate 101 and the lower substrate 102 together.

The convex lens 100 is a circular axisymmetric aspherical lens or a spherical lens as shown in FIG.
The position of the diaphragm aperture 200 in the optical axis direction determines the off-axis chief ray of the optical system, and its position is extremely important in controlling various aberrations. In the case of a lens having a convex single surface on the object side, if there is no thick air layer between the convex lens 100 and the semiconductor chip 104, it is an intermediate position between the convex lens 100 and the semiconductor chip 104, and the distance is internally divided into about 1: 2. Placing a stop at the position is preferable because various optical aberrations can be satisfactorily corrected. Therefore, as shown in FIG.
A circular aperture opening 200 coaxial with the convex lens 100 was formed by the second light shielding layer 103.

Further, the range of the diaphragm light-shielding layer 103 formed on the lower substrate 102 is limited because the adhesive 105, which will be described later, is irradiated with ultraviolet rays to be cured, and therefore, the transparent area 1021.
There is.

In other words, the transparent region 1021 can cure the adhesive 105 shown in FIG. 2C by irradiating the front surface of the semiconductor chip 104 with ultraviolet rays (direction A in FIG. 4). The irradiation from the front of the semiconductor chip 104 as referred to in this specification means the irradiation from the direction A.

The diaphragm light-shielding layer 103 is formed by depositing or sputtering a thin film of Inconel, chromel, chrome, or the like. By continuously controlling the position of the shield in the sputtering process, the transmittance can be arbitrarily controlled as in printing.

Moreover, the MTF of the imaging system can be controlled by making the transmittance in the aperture 200 a function of the distance from the optical axis. Here, the light receiving element array 300
In order to reduce the aliasing distortion due to the discrete sampling due to, the transmittance is set to increase monotonically from the periphery to the center, and in particular, the response to low spatial frequencies is improved and the response to high spatial frequencies is reversed. It is controlled.

An optical element 107 is provided on the semiconductor chip 104.
An object image is formed by the semiconductor chip 104
Photoelectric conversion is performed by the light receiving element array 300 provided above, and it is captured as an electric signal. The light-receiving element array 300 is an array in which a large number of pixels are arranged in a two-dimensional direction, and a color filter may be provided for each pixel when appropriately capturing a color image, or
In order to set an RGB filter array called a Bayer array and further to have an infrared cut function, an element that absorbs infrared light such as copper ions is included in the material of both or one of the upper and lower substrates 101 and 102. Include it.

In the image pickup module shown in FIG. 1, since the optical element 107 having the same projected shape as that of the semiconductor chip 104 is fixed on the semiconductor chip 104, the rear surface electrode is used to electrically connect to an external electric circuit. .

As an example thereof, in this embodiment, as shown in FIG. 3, the penetrating metal body 1 penetrating the semiconductor chip 104.
The front surface electrode on one main surface of the semiconductor chip 104 and the back surface electrode on the other main surface are electrically connected by 06.

The optical element 107 and the semiconductor chip 104 are bonded together with an adhesive 105. As the adhesive 105, an ultraviolet curable resin or a thermal ultraviolet curable resin is used. Furthermore, the adhesive 105 is more preferably a thermo-ultraviolet curable resin as a sealing material because the thickness can be easily controlled. Further, the thermo-ultraviolet curable resin includes the above-mentioned epoxy resin and the like. In this embodiment, the adhesive 10
Reference numeral 5 is a sealing material formed by screen-printing a thermal ultraviolet curing type epoxy resin. The thermo-ultraviolet curable epoxy resin is cured by heating and irradiation with ultraviolet rays. Epoxy resins are suitable for this application because they cure slowly, have no unevenness in curing shrinkage, and relax stress. There is a type of adhesive that is hardened by heating, but sufficient heating to harden the thermosetting epoxy resin is performed by a color filter (not shown) formed on the semiconductor chip 104, a replica portion, a microlens, a diaphragm. Light shielding layer 103
The UV-curable resin or the heat-UV-curable resin is more preferable because it may deteriorate the printing paint and the like.

The method of forming the adhesive is not limited to screen printing, and it may be formed by another printing method, coating method, or the like.

Here, the bonding step will be described. The optical element 107 is placed on the semiconductor chip 104, and the adhesive 10
After 5 is semi-cured by ultraviolet irradiation, it is pressed and slightly heated to be completely cured, and a gap between the optical element 107 and the semiconductor chip 104 is set, so that an object image is sharpened on the light-receiving element array 300. Adjust to form an image on.

The optical element 107 and the semiconductor chip 104
Since a gap is provided without filling the space between and with the resin, the imaging position can be adjusted without requiring a large force.

At this time, as described above, the transparent region 1021 is formed around the light shielding layer 103 of the lower substrate 102 as described above.
As shown in FIG. 4, the adhesive 105 is formed by irradiating ultraviolet rays (arrow A) from the front surface of the semiconductor chip.
Can be easily and reliably cured. The transparent region 1021 may be transparent to ultraviolet rays and may be opaque to light of other wavelengths.

As described above, since the adhesive 105 is formed in the light incident direction via the transparent region 1021, it is possible to easily seal the periphery of the light receiving element array. An imaging module could be provided. Therefore, it is possible to prevent the ingress of dust, the deterioration of the microlens and the filter layer due to the humidity in the air, and the electrolytic corrosion of the aluminum layer.

Next, a method for mass-producing the image pickup module of the present invention shown in FIG. 1 will be described with reference to FIGS.

The optical element 107 and the semiconductor chip 104 are characterized in that they are joined at the stage of the semiconductor wafer and the optical element assembly at the stage before they are separated. In the present specification, the upper substrate 10 that constitutes one imaging module
1 and the lower substrate 102 are used as optical elements 107, and a stage before being separated into the optical elements 107 constituting one image pickup module is called an optical element assembly. Similarly, the upper substrate 10
The upper substrate assembly and the lower substrate 1 are the steps before separating them into 1
The lower substrate assembly is a stage before being separated into 02.
Therefore. The optical element assembly is a large light-transmissive plate-like body having a bonded structure of an upper substrate assembly and a lower substrate assembly.

FIG. 5 is a top view of the upper substrate assembly in the manufacturing process of the imaging module of the first embodiment of the present invention, and FIG. 6 is a top view of the lower substrate assembly in the manufacturing process of the imaging module of the first embodiment of the present invention. FIG. 7 is a top view of the semiconductor wafer in the manufacturing process of the image pickup module of the first embodiment of the present invention, and FIG. 8 is a schematic cross-sectional view of the adhesive curing process in the manufacturing process of the image pickup module of the first embodiment of the present invention. is there.
9A is a top view of a step of separating the imaging module from the optical element semiconductor wafer bonded body in the manufacturing process of the imaging module according to the first embodiment of the present invention, and FIG. 9B is a line 9B-9B in FIG. 9A. FIG. 10 is a schematic cross-sectional view showing a cross section in FIG. 10, and FIG. 10 is a top view in which two convex lenses are formed on the upper substrate aggregate.

First, 117 in FIG. 5 is an upper substrate assembly, 114 in FIG. 6 is a lower substrate assembly, 1141 is a transparent region in the peripheral portion of the diaphragm light-shielding layer 103, and in FIG.
10 is a semiconductor wafer, 109 is an orientation flat of the semiconductor wafer 110, 111 is a boundary line of semiconductor chips, and in FIG. 8, 119 is an optical element assembly in which an upper substrate assembly 117 and a lower substrate assembly 114 are bonded together.

Since the outer shape of the diaphragm light-shielding layer 103 of the lower substrate assembly 114 shown in FIG. 6 is limited to an island shape due to the curing of an ultraviolet-curable resin which is an adhesive described later, the area of the diaphragm light-shielding layer 103 is limited. There is a transparent region 1141 in the peripheral portion. The position of the aperture 200 in the optical axis direction determines the off-axis chief ray of the optical system, and the aperture position is extremely important in controlling various aberrations. In the case of a lens having a single surface convex on the object side, the convex lens 100 and a semiconductor wafer 110 described later are used.
If there is no air layer between them, various optical aberrations can be satisfactorily corrected by placing the diaphragm at an intermediate position between the convex lens 100 and the semiconductor wafer 110 and at a position where the distance is internally divided into about 1: 2. Therefore, the aperture opening 200 coaxial with the convex lens 100 is formed by the light shielding layer 103 of the lower substrate assembly 114.

Upper substrate assembly 117 and lower substrate assembly 1
Reference numeral 14 is made of glass or transparent resin, and when made of glass, it is made by a glass molding method, and when made of resin, it is made by injection molding, compression molding or the like. Further, the upper substrate assembly 117 may have a structure in which a resin lens portion is added on the flat glass substrate by the replica manufacturing method. It is particularly preferable to use borosilicate glass for the lower substrate assembly 114, because the difference in linear expansion from the semiconductor wafer is small and the stability with respect to temperature change is high. In order to prevent the occurrence of α-ray-induced defects in the semiconductor wafer, it is preferable to use optical glass having a low α-ray surface density for both the upper substrate assembly 117 and the lower substrate assembly 114. It is desirable that the α-ray surface density is lower than that of the upper substrate.

Upper substrate assembly 117 and lower substrate assembly 114
Of the optical element assembly 1 by bonding the
By not creating an interface between air and the substrate inside 19, the generation of ghosts is prevented.

It is preferable that a large number of convex lenses 100 and aperture openings 200 are provided on each substrate and that they have a coaxial relationship when the substrates are bonded together. Further, it is desirable that the pitch be equal to the pitch of semiconductor chips formed on the semiconductor wafer described below.

On the other hand, FIG. 7 is a top view of the semiconductor wafer. The semiconductor wafer 110 shown in FIG. 7 is provided with a large number of light receiving element arrays 300 and circuits (not shown), which are cut along the boundary line 111 and connected to an external electric circuit so that each functions as a semiconductor chip 104. To do. In FIG. 7, arrow B indicates the position and moving direction of the dicing blade in the subsequent dicing process.

An object image is formed on the semiconductor wafer 110 for each convex lens 100 of the optical element assembly 119, and this is photoelectrically converted by the light receiving element array 300 provided on the semiconductor chip and captured as an electric signal. The light receiving element array 300 is an array in which a large number of pixels are arranged in a two-dimensional direction. When capturing a color image, each pixel is provided with a color filter, and for example, an RGB filter array called a Bayer array is set. In order to provide the above, it is preferable that an element that absorbs infrared light, such as copper ions, is included in the material of both or one of the upper substrate assembly 117 and the lower substrate assembly 114.

As shown in FIG. 8, an optical element assembly 119.
The semiconductor wafer 110 and the convex lens 100, which is an image forming section, and the light receiving element array 300 (not shown) are positioned in a predetermined relationship and then bonded. Since the semiconductor wafer 110 is a crystal, its electrical, optical, mechanical, and chemical properties are anisotropic. Therefore, the pulled ingot is sliced after measuring the plane orientation with high accuracy by a method using X-ray diffraction. Prior to this slice, a linear portion called an orientation flat is formed on a cylindrical ingot in order to show the crystal orientation. A semiconductor wafer 110 is shown in FIG.
It is an orientation flat.

At the semiconductor wafer manufacturing stage, the light-receiving element array 30 is aligned with the orientation flat 109.
A semiconductor element pattern such as 0 is formed on the other hand, and on the other hand, on the optical element assembly 119, for example, a reference pattern as a printing reference of the diaphragm light-shielding layer 103 on the lower substrate assembly 114 is provided to lower the orientation flat 109 and the lower surface. If it is used for alignment with the reference pattern of the substrate assembly 114, extremely precise alignment can be achieved. Moreover, in this case, the optical element assembly 119 and the semiconductor wafer 1
There is an extremely great advantage that the alignment is completed for all of the imaging modules that are separated and completed in the subsequent process by performing the alignment once with 10.

As the adhesive 105 shown in FIG. 7, a thermal ultraviolet curing type epoxy resin is formed by screen printing or the like.
Further, it is more preferable to use the epoxy resin sealing material whose thickness is easily controlled as in the present embodiment. Epoxy resin is suitable for this application because it cures slowly, has no unevenness in curing shrinkage, and relaxes stress. In addition, there are epoxy resins that are hardened by heating,
The reason why the thermal ultraviolet ray curable type is selected here is that sufficient heating to cure the thermosetting type epoxy resin does not apply to a color filter, a replica portion, a microlens, and a coating material for printing the diaphragm light-shielding layer 103 which are not shown. This is because it may deteriorate.

In this bonding step, as shown in FIG. 9A, the optical element assembly 119 is placed on the semiconductor wafer 110, the epoxy resin as the adhesive 105 is semi-cured by ultraviolet irradiation, and then pressed and slightly pressed. The optical element assembly 119 and the semiconductor wafer 1 are heat-treated and completely cured.
The gap between the object image and the light receiving element array 3 is set.
00 so that a sharp image is formed on the image.

At this time, since the transparent region 1141 is formed in the peripheral portion of the stop light-shielding layer 103 of the lower substrate assembly 114 as described above, as shown in FIG. 8, irradiation of ultraviolet rays from the front surface of the semiconductor wafer is performed. The epoxy resin of the adhesive 105 can be surely and easily cured by (arrow C).
At this time, by bonding and fixing at the semiconductor wafer stage,
The effect of preventing blurring of the optical image can also be expected. The transparent region 1141 may be transparent to ultraviolet rays and may be opaque to light of other wavelengths.

Optical element assembly 119 and semiconductor wafer 11
After 0 and 0 are fixed, the process moves to a dicing step for cutting the optical element semiconductor wafer bonded body into image pickup modules.

Next, this step will be described with reference to FIGS. 9 (A) and 9 (B).

For dicing a semiconductor wafer, a glass substrate or a resin substrate, a cutting machine or a laser processing machine disclosed in, for example, Japanese Patent Laid-Open No. 11-345785 and 2000-061677 is used.
When cutting is performed using a dicing blade as in the former case, the dicing blade 123 shown in FIG. 9 (B) is controlled along arrow B shown in FIG. 9 (A) while being cooled by applying cutting water. In the actual process, the optical element semiconductor wafer bonded body may be cut while being fed, or may be cut at one time using a plurality of dicing blades.

At this time, the dicing marks are grooves formed by etching the lower substrate assembly 114 or the upper substrate assembly 117, metal marks formed by photolithography technique,
Alternatively, the convex portion of the resin formed by the replica is used. In particular,
If the replica is formed at the same time as the lens that is the image forming action portion, the manufacturing process can be reduced.

In the dicing step of the optical element semiconductor wafer bonded body, half-cut dicing is performed to leave the semiconductor wafer 110 at 50 to 100 μm. Since the adhesive agent 105 for adhering the semiconductor wafer 110 and the optical element assembly 119 is provided avoiding the dicing position of the semiconductor wafer 110, the adhesive agent 105 is melted by frictional heat with the dicing blade or carbon particles are formed. It will be attached to the lens surface and deteriorate the quality of the imaging module.

When a laser processing device is used for dicing on the optical element side, generation of glass particles is suppressed, and improvement in yield can be expected. Further, as shown in FIG. 11, the dicing blade 153 is attached to the semiconductor wafer 1
Put from the 10 side, the upper substrate assembly 117 50 ~ 100
Half-cut dicing that leaves μm may be performed.

In the breaking step subsequent to the dicing step, a portion of the semiconductor wafer 110 left uncut by 50 to 100 μm or 50 to 100 μm of the upper substrate assembly 117 is left.
The part left uncut by m is divided using a predetermined roller.

The image pickup module obtained after being divided by the above steps is the same as the image pickup module of the form shown in FIG. The electrical connection to the external electric circuit may be made by the back electrode connected to the penetrating metal body 106 shown in FIG. 3 as in the first embodiment.

The optical element assembly does not necessarily have to have the same number of optical elements as the semiconductor chips formed on the semiconductor wafer. For example, in the optical element assembly 151 shown in FIG. 10, two convex lenses 150 are provided on the upper substrate 150.
a and 150b are formed, and the semiconductor wafer 11 shown in FIG.
Sixteen optical element aggregates 150 are fixed on the surface of the optical disc 0, and each of them is divided into two optical elements in the subsequent dicing process to finally obtain 32 image pickup elements.

As described above, the number of optical elements formed on the optical element assembly is made smaller than the number of semiconductor chips formed on the semiconductor wafer, and further, a slight gap is provided between the optical element assemblies. Even if the flatness of the semiconductor wafer, which has been improved in accuracy by suctioning the back surface to the jig, deteriorates as the suction is released, the positional relationship between the optical element and the semiconductor chip hardly deteriorates. Recently, the tendency for the diameter of a semiconductor wafer to become larger has become stronger, but with such a structure, a high yield rate can be easily obtained.

By thus sealing with the adhesive 105, it becomes possible to prevent the entry of dust and the deterioration of the microlenses and filter layers due to the humidity in the air, or the electrolytic corrosion of the aluminum layer. Moreover, since the sealing can be performed in the semiconductor manufacturing process, the effect is greater.

(Second Embodiment) An image pickup module according to a second embodiment of the present invention will be described with reference to FIGS.

FIG. 12 is a schematic cross-sectional view of an image pickup module according to the second embodiment of the present invention, and FIG. 13A is an upper surface of a lower substrate which is an element constituting an optical element of the image pickup module according to the second embodiment of the present invention. FIG. 13 (B) is a top view showing the semiconductor chip of the image pickup module of the second embodiment of the present invention, and FIG. 14 is an optical element assembly and a semiconductor in the manufacturing process of the image pickup module of the second embodiment of the present invention. It is a top view of a semiconductor wafer at the time of bonding a wafer.

In FIG. 12, 120 is a sealing material as an adhesive, 122 is an adhesive formed to seal the opening 400, and 400 in FIG. 13 is such that the sealing material 120 does not completely surround the light receiving element array 300. It is an opening provided in the.

The parts having the same reference numerals have been described above, and the description thereof will be omitted. This embodiment is different from the first embodiment in that the optical element 107 and the semiconductor chip 10 are different.
That is, the adhesive used for bonding 4 and 4 improves the imaging performance, and has a shape suitable for obtaining high accuracy in aligning the optical element 107 and the semiconductor chip 104. .

Specifically, when the pattern of the sealing material 120 is used in the pressing process of bonding the optical element 107 and the semiconductor chip 104, the semiconductor chip 10
4, the gas confined in the region surrounded by the optical element 107 and the sealing material 120 goes out through the opening 400, so that the internal pressure does not rise.

Therefore, the harmful reaction force is the optical element 107.
Or the sealing material 120 does not gradually move from the inner side to the outer side due to the increase of the internal pressure due to its viscosity, so that the optical element 107 and the semiconductor chip 104 are aligned with higher accuracy. It is suitable above.

That is, the effect of providing a gap between the optical element 107 and the semiconductor chip 104, which is not filled with the resin, which is described in the first embodiment, can be more greatly enhanced.

The adhesive is not limited to the sealing material 120 and may be an ultraviolet curable resin. In this embodiment, an epoxy resin, which is a thermal ultraviolet curable resin and is a sealing material, is used.

After the sealing material 120 is completely cured by irradiation of ultraviolet rays from the front side of the semiconductor chip 104, the opening portion 400 of the sealing material 120 is closed with the adhesive 122. At this time, a thermo-ultraviolet curable resin is suitable as the adhesive 122, and the same epoxy resin as the sealing material 120 is used in this embodiment. Similarly, the adhesive 122 is cured by irradiation with ultraviolet rays from the front direction of the semiconductor chip 104.

The adhesive agent 120 and the adhesive agent 122 may be cured not only by irradiation with ultraviolet rays but also by appropriate heat.

Therefore, similarly to the first embodiment, the diaphragm light-shielding layer 10
The transparent region 1021 is formed so that the epoxy resin 122 can be cured by irradiating ultraviolet rays from the front of the semiconductor chip 104 while limiting the range of No. 3. Therefore, a large number of image pickup modules can be arranged in parallel to irradiate ultraviolet rays at one time, which is extremely advantageous in terms of cost.

Alternatively, as in the first embodiment, as shown in FIG. 14, the optical element assembly and the semiconductor chip may be joined at the stage before the optical element assembly and the semiconductor wafer are separated from each other. The difference between FIG. 14 and FIG. 2C is the adhesive pattern as described above. The adhesive 120 of the present embodiment has the opening 400, and when the optical element assembly is placed on the semiconductor wafer 110 and pressed, the gas emitted from the opening escapes to the outside through the boundary line 111 of the semiconductor chip. The harmful reaction force is not applied to the optical element assembly (not shown), and the alignment with the semiconductor wafer 110 can be performed with high accuracy. It goes without saying that the effects obtained in the first embodiment can be obtained in the same manner.

(Third Embodiment) Next, a third embodiment of the present invention.
The image pickup module will be described with reference to FIGS. 15 to 23.

The present embodiment is different from the second embodiment in that it has an optimum configuration for connecting to an external electric circuit via a surface electrode.

Furthermore, an example is shown in which the resin thickness on the dicing line is reduced in the dicing process for cutting the optical element semiconductor wafer bonded body into image pickup modules.

FIG. 15A is a top view showing the lower substrate of the image pickup module of the third embodiment of the present invention, and FIG. 15B is a top view showing the semiconductor chip of the image pickup module of the third embodiment of the present invention. Is.

In FIG. 15, 132 is the semiconductor chip 1.
No. 04 electrode pad. Also, the parts denoted by the same reference numerals have been described above, and description thereof will be omitted.

The two broken lines between FIG. 15 (A) and FIG. 15 (B) indicate the lower substrate 102 in this imaging module.
Shows the positional relationship between the semiconductor chip 104 and the semiconductor chip 104, and shows that the lower substrate 102 and the semiconductor chip 104 are fixed to each other with a certain distance in the lateral direction of the drawing. Further, it is more preferable that the lower substrate 102 and the semiconductor chip 104 have the same outer dimensions because the manufacturing method is simple.

Further, as shown in FIG. 15 (B), the semiconductor chip 104 is connected to an external electric circuit via the electrode pad 132 at the end (upper open position in which the sealing material is not provided and the upper part is opened). The sealing material 120 is located inside the electrode pad 132.
Further, as in the first embodiment, since the thermo-ultraviolet curable resin of the sealing material 120 formed on the semiconductor chip 104 can be irradiated with ultraviolet rays, the diaphragm light shielding layer 103 of the lower substrate 102 is formed inside the sealing material 120. And the sealing material 120
A transparent region 1021 is located directly above.

The lower substrate and the semiconductor wafer before cutting which satisfy the above positional relationship are shown in FIGS. 16 and 17, respectively.
It was shown to.

FIG. 16 is a top view of the lower substrate assembly in the manufacturing process of the image pickup module according to the third embodiment of the present invention, and FIG.
FIG. 6A is a top view of a semiconductor wafer in a manufacturing process of an image pickup module according to a third embodiment of the present invention.

In this embodiment, the lower substrate assembly and the semiconductor wafer are first bonded and then the upper substrate assembly is bonded. With such a process, the ultraviolet light radiated toward the sealing material 120 only passes through the lower substrate 102 and the sealing material 12
Since it reaches 0, light absorption in the substrate can be suppressed to a small level. Therefore, the ultraviolet effect resin can be cured with a small amount of light and in a short time, so that the number of steps can be shortened.

The lower substrate assembly 114 and the semiconductor wafer 1
The bonding step with 10 is the same as in the first embodiment.

The adhesive may be the pattern of the sealing material 105 shown in the first embodiment, but in the present embodiment,
The pattern of the sealing material 120 described in the second embodiment is used.

FIG. 18 is a top view of the upper substrate assembly in the manufacturing process of the image pickup module according to the third embodiment of the present invention. The optical element assembly is formed by being fixed on the lower substrate assembly 117.

In FIG. 18, reference numeral 142 is a dicing line (only vertical dicing lines are shown in the figure).

FIG. 19 is a schematic sectional view taken along the line 19-19 in FIG. The dicing line 142 is formed by partially thinning the resin 141 formed on the glass substrate 140. Dicing mark is convex lens 1
Since a replica can be formed at the same time as 00, the manufacturing process can be reduced. Alternatively, it may be a groove formed by etching or the like on the back surface of the semiconductor wafer 110 or the surface of the lower substrate assembly 114 or the upper substrate assembly 117, a metal mark formed by a photolithography technique, or a resin protrusion formed by a replica. .

Since the resin in the dicing line 142 is only thin and is not divided, the gate is set at the end of the upper substrate assembly 117 so that the convex lens can be formed by the injection manufacturing method. 10
0 can be easily formed. The upper substrate assembly 117 is precisely aligned with the semiconductor wafer 133 and then fixed to the lower substrate assembly 114.

Next, a dicing process for dividing the optical element semiconductor wafer bonded body thus manufactured into image pickup modules will be described.

FIG. 20 is a schematic sectional view showing the dicing process of the bonded optical element semiconductor wafer in the manufacturing process of the image pickup module according to the third embodiment of the present invention.

In FIG. 20, reference numeral 138 is the upper substrate assembly 1.
17, an optical element semiconductor wafer bonded body formed by bonding the lower substrate aggregate 114 and the semiconductor wafer 110 together,
Reference numeral 136 is a dicing blade for dicing the optical element assembly 119 composed of the upper substrate assembly 117 and the lower substrate assembly 14, and 137 is a dicing blade for dicing the semiconductor wafer 110.

In this embodiment, dicing is performed from the upper and lower surfaces of the bonded optical element semiconductor wafer assembly 138. It is advisable to control the dicing blades 136 and 137 along the positions shown in FIG. 20 while cooling by applying cutting water during dicing.

In the dicing process, the optical element semiconductor wafer bonded body 138 may be cut while being fed, or may be cut at one time by using a plurality of dicing blades. Further, the upper and lower surfaces may be diced on each side, or both surfaces may be diced simultaneously.

In this dicing process, since the resin 141 forming the dicing line 142 is sufficiently thin, the resin 141 is melted by frictional heat with the dicing blade, becomes fine fragments, or becomes carbon particles. Then, it hardly adheres to the lens surface and deteriorates the quality of the imaging module.

In this dicing step, half-cut dicing is performed to leave the semiconductor wafer 110 and the lower substrate aggregate 114 by 50 to 100 μm. In the breaking process following the dicing process, 50 to 1 of the semiconductor wafer 133 is
The portion left uncut by 00 μm is divided using a predetermined roller.

FIG. 21 is a top view of the image pickup module of the third embodiment of the present invention, and FIG. 22 is a schematic sectional view taken along line 22-22 of the image pickup module of FIG. Upper substrate 10
The semiconductor chip 104 is located in the back of 1, and the electrode pad 132 is located at this position. In this embodiment, the optical element 107 including the upper substrate 101 and the lower substrate 102 and the semiconductor chip 104 are bonded or fixed to each other with a certain gap in one direction.

FIG. 23 is a schematic sectional view showing a connection state and a sealing state between the image pickup module of the third embodiment of the present invention and an external electric circuit. In FIG. 23, 146 is a flexible printed circuit board, which is an external electric circuit board, and 147.
Is a bonding wire for electrically connecting the electrode pad 132 of the imaging module 154 and an electrode pad (not shown) on the flexible printed circuit board 146, and 148 is a sealant around the electrode pad and the bonding wire 147. This is a thermo-ultraviolet curable resin.

The thermal UV-curable resin 148 is applied over the entire circumference of the image pickup module 154 in order to secure the mounting stability of the image pickup module 154 on the flexible printed board 146. In addition, the reason why the thermo-ultraviolet curable resin is selected here is that the heating sufficient to cure the thermosetting epoxy resin is not performed on the color filter, the replica portion, the microlens, which are formed on the semiconductor wafer 133, This is also because there is a risk that the printing paint or the like of the diaphragm light-shielding layer 103 may deteriorate.

When the thermal ultraviolet curing resin 148 is cured, ultraviolet irradiation is mainly performed from above the upper substrate 140.
In order to prevent the electrode pads 132 of the semiconductor chip 104 from being corroded, the side surface of the lower substrate 102 and the thermal ultraviolet curable resin 14 are used.
Adhesion with 8 is extremely important.

The area of the diaphragm light-shielding layer 103 is covered with the sealing material 120.
If not limited to the inside of the, the ultraviolet rays reach the sealing portion of the lower substrate 102 through the layer of the thermal ultraviolet curable resin 148, so that this portion is the last to be cured. In the image pickup module, since the range of the diaphragm light-shielding layer 103 is limited to the inside of the sealing material 120, there is an optical path of ultraviolet rays to the sealing portion of the lower substrate 102 indicated by arrow E. According to this optical path, thermal ultraviolet curing is performed. It is possible to surely cure and seal the thermal ultraviolet curable resin 148 without passing through the layer of the mold resin 148. Further, the optical path indicated by the arrow F provides high stability of attachment to the flexible printed board 146.

As described above, by sealing with the sealing material 120 and the thermo-ultraviolet curable resin 148, the microlenses and the filter layer are deteriorated due to the entry of dust or the humidity in the air, or the aluminum layer is electrically charged. It becomes possible to reliably prevent food. Further, since the surface electrode is connected to the external electric circuit by the bonding wire, the ITO film and the penetrating metal body are not required, and the manufacturing can be performed at low cost. Further, it can be applied to electrical connection using a TAB film without using a bonding wire.

(Fourth Embodiment) A fourth embodiment of the present invention will be described with reference to FIGS. The present embodiment is different from the first to third embodiments in that a concave portion is formed in the optical element so that the resin does not protrude from the surface.

FIG. 24 is a schematic cross-sectional view showing a step of irradiating an optical element-semiconductor wafer bonded body with an ultraviolet ray in the manufacturing process of the image pickup module according to the fourth embodiment of the present invention.

First, in FIG. 24, 163 is a semiconductor wafer on which a plurality of semiconductor chips are formed, 165 is an adhesive layer, and 160 is an optical element assembly in which convex surfaces are formed on the bottoms of a plurality of concave portions. The optical element assembly 160 is an optical element that is separated from each other and mounted on one imaging module. Reference numeral 168 is a resin layer that fills the concave portion of the optical element assembly 160 and planarizes it. The refractive index of the resin layer 168 is lower than that of the optical element assembly 160, and the convex lens 1 as a whole.
It has the function of 61, and this interface serves as an image forming section. Since the optical element assembly 160 is flattened by the resin layer 168, it is easy to attach the imaging module to the holding member by utilizing this portion. Also,
Reference numeral 164 is a penetrating metal body that penetrates the semiconductor chip for forming the back surface electrode. The penetrating metal body 164 is for electrically connecting to an external electric circuit by the back surface electrode.

The parts having the same reference numerals have been described above, and the description thereof will be omitted.

As the optical element assembly 160, for example,
It is made of glass. The adhesive layer 165 may be formed so as to surround the light receiving element array of the semiconductor chip as in the first and second embodiments, but may be formed on the entire surface of the semiconductor chip. However, in this case, it is desirable to form the adhesive layer 165 while avoiding the dicing position.

On the semiconductor wafer 163, a large number of electric circuits which will be cut into semiconductor chips in a later step are formed.
Each has a light receiving element array. Optical element assembly 16
0 and the resin layer 168 form an image forming portion on the semiconductor wafer 16
3 has an optical path length for forming an object image on the surface 3 and its pitch is equal to the pitch of the semiconductor chips formed on the semiconductor wafer 163.

The main steps until the completion of the image pickup module are the known steps of forming a circuit pattern on the semiconductor wafer 163, the step of forming a lens on the optical element assembly 160, and the semiconductor wafer 163 as in the above-described embodiment. These are the step of aligning and adhering with the optical element assembly 160 and the step of dicing.

In the steps of alignment and adhesion, first, a space between the semiconductor wafer 163 and the optical element assembly 160 is filled with an adhesive layer 165 of a thermal ultraviolet curing epoxy resin without forming an air layer, and the optical element assembly is formed. The gap between the body 160 and the semiconductor wafer 163 is set and adjusted so that the object image is sharply formed. There is a type of epoxy resin that is cured by heating, but the reason why the thermal ultraviolet curing type is selected here is that the semiconductor wafer 163 was heated sufficiently to cure the thermosetting epoxy resin. This is because the color filter and the resin layer (not shown) may be deteriorated.

Next, as shown by an arrow G in FIG. 24, diffused irradiation of ultraviolet rays is performed to cure the epoxy resin of the adhesive layer 165 to cure the semiconductor wafer 163 and the optical element assembly 160.
Stick and. In parallel light irradiation, the irradiation light converges on one point on the axis due to the image forming action of the image forming action portion. However, since diffused irradiation is used here, the adhesive layer 165 located below the image forming action portion is used. Ultraviolet rays reach the whole and the adhesive layer 16
5 can be sufficiently cured.

In the subsequent dicing step, full dicing is performed along the boundary line 166 shown in FIG. 24 to cut.
Then, if each is connected to an external electric circuit, each functions as an imaging module. In this dicing process, a recess is formed in the optical element assembly 160 so that the resin does not protrude from the surface, and the resin is removed from the position where the dicing blade passes, so the resin melts due to friction heat with the dicing blade. The fine fragments or carbon particles do not adhere to the lens surface and deteriorate the quality of the imaging module.

FIG. 25 is a schematic sectional view showing an image pickup module according to the fourth embodiment of the present invention. In FIG. 25, 1
Reference numeral 73 is a semiconductor chip, 165 is an adhesive layer, and 170 is an optical element separated from the optical element assembly.

In the present embodiment, by sealing with the adhesive layer 165, it is possible to prevent dust from entering, deterioration of the filter layer due to humidity in the air, or electrolytic corrosion of the aluminum layer of the semiconductor chip 173. Become. Moreover, since the sealing can be performed in the semiconductor manufacturing process, the effect is greater. In addition, since the alignment with the optical element can be performed at one time at the semiconductor wafer stage, it is possible to significantly reduce the adjustment man-hours.

(Fifth Embodiment) FIG. 26A is a top view of an image pickup module according to a fifth embodiment of the present invention, and FIG. 26B is a schematic cross-sectional view taken along line 26B-26B of FIG. 26A. 26C is a top view of a semiconductor chip that is one element of the image pickup module according to the fifth embodiment of the present invention.

In FIG. 26, 560 is an infrared cut filter, 550 is a light-transmissive plate, and 506 is a light-shielding member formed on the upper surface of the light-transmissive plate through the infrared cut filter 560 by, for example, offset printing. The stop light shielding layer 512 is an infrared cut filter, and the stop light shielding layer 506.
And four convex lenses 601, 603 as an image forming section,
And a convex lens 603 and a convex lens 604 not shown
A compound eye optical element having a compound eye lens composed of
Although the convex lenses 602 and 604 are not shown in the schematic cross-sectional view shown in FIG. 26B, the diaphragm aperture described later and the optical axis are coaxial. Reference numeral 503 denotes a semiconductor chip 522 in which pixels (not shown) including light receiving elements are two-dimensionally formed.
Is a spacer that defines the distance between the compound-eye optical element 512 and the semiconductor chip 503, and 509 is an ultraviolet effect resin as an adhesive that bonds the compound-eye optical element 512 and the semiconductor chip 503 via the spacer 522, 811, 812,
Reference numerals 813 and 814 denote diaphragm openings 513 in which the diaphragm light shielding layer 506 is not formed on the upper surface of the compound-eye optical element 512.
Is an electrode pad as an external terminal portion, 508 is a light-shielding portion formed in a space surrounded by the compound-eye optical element 512, the spacer 522, and the semiconductor chip 503 to prevent optical crosstalk of the four convex lenses, and 516 is a light receiving portion. Microlenses 821, 822, 82 for increasing the light collection efficiency of the element
3 and 824 are light receiving element arrays plurally formed on the semiconductor chip 503 two-dimensionally, and 514 is a light receiving element array 821, 8
An AD conversion circuit 515 for converting the output signals from 22, 823 and 824 into a digital signal is a light receiving element array 821,
822, 823, and 824 are timing generators that generate timing signals for photoelectric conversion operations.

The image pickup module of this embodiment has a structure in which the compound eye optical element 512 and the semiconductor chip 503 are integrated, and a sensor package and a lens barrel are not required.

As in the other embodiments, the object light incident on the compound-eye optical element 512 from above in FIG. 26B forms a plurality of object images on the semiconductor chip 503, and Photoelectric conversion is performed in each light receiving element.

The convex lenses 811 to 814 are Fresnel convex lenses made of resin formed on the lower surface of the compound-eye optical element 512 by, for example, the replica manufacturing method. Other than the replica manufacturing method, a method of integrally forming with the substrate by a method such as injection molding or compression molding using a convex lens portion as a resin may be used. The convex lenses 601, 602, 603, and 604 are circular axisymmetric aspherical Fresnel convex lenses or spherical Fresnel convex lenses, and particularly correct the field curvature better than an ordinary optical system using a continuous surface.

A stop light-shielding layer 506 and an infrared cut filter 560 are formed on the upper surface of the light transmissive plate member 550. As the infrared cut filter 560, an infrared cut filter utilizing the interference of light in the dielectric multilayer film is deposited on the entire surface of the light transmissive plate-like body 550, and then the diaphragm light shielding layer 506 is formed thereon. No masking is required, which is very advantageous in terms of cost, which is preferable. still,
The infrared filter is not necessarily formed and may be omitted. If it is not present, a thinner imaging module can be formed.

In the present embodiment as well, as in the first embodiment, the area of the diaphragm light-shielding layer 506 has an island shape in order to cure the ultraviolet curable resin as the adhesive 509 by irradiating it with ultraviolet rays as described later. Are restricted to In this embodiment, as the adhesive 509, an epoxy resin which is a thermo-ultraviolet curable resin, which is a sealing material whose thickness is controlled in advance, is used.

Aperture openings 811, 812, 813 and 81
The position of 4 in the optical axis direction determines the off-axis chief ray of the optical system, and the diaphragm position is extremely important in controlling various aberrations. In the image forming section composed of a Fresnel lens having a convex surface on the image side, it is preferable to place a diaphragm near the center of a spherical surface that approximates Fresnel, because various optical aberrations can be corrected well. Therefore, as shown in FIG. 26A, four circular aperture openings 811, 812, 813 and 8 are formed on the upper surface of the compound-eye optical element 512.
14 is formed.

The compound eye optical element 5 is provided on the semiconductor chip 503.
Four object images are formed by 12, and four object images are formed on the semiconductor chip 503.
It is photoelectrically converted by 822, 823, and 824, and is captured as an electric signal. Each light receiving element has a microlens 516 to enhance the light collection efficiency. Each of the four light receiving element arrays has a green transmission (G) filter and a red transmission (R) filter.
A filter, a blue transmission (B) filter, and a green transmission (G) filter are formed, and four images separated into the three primary colors can be taken out.

Semiconductor chip 503 and compound-eye optical element 512
The distance between the spacer 522 and the spacer 522 is determined by the total thickness of the adhesive 509 formed on the spacer 522 and made of a thermal ultraviolet curing epoxy resin. The spacer 522 is configured to fix a component manufactured using a material such as resin, glass, or silicon to the semiconductor chip. Spacer 522 and semiconductor chip 5
03 (SOI (Silicon on)
The bonding process at the time of manufacturing an Insulator substrate can be applied.

Further, the compound eye optical element 512 and the spacer 52
By adjusting the thickness of the sealing material 509 during the bonding with the second lens 2, the accuracy of the gap between the compound eye optical element 512 and the semiconductor chip 503 can be adjusted. These bonding steps are performed at the semiconductor wafer stage.

The compound eye optical element 5 is provided on the semiconductor chip 503.
Four object images of RGBG are formed by 12, and these are photoelectrically converted by the light receiving element arrays 821, 822, 823, and 824, and are captured as electric signals.

In this embodiment, the light collection efficiency is improved by the microlenses 516 formed on each light receiving element array, and the image pickup module is capable of easily picking up an image of a low-luminance object.

Further, the microlens 516 is arranged so as to be eccentric with respect to the light receiving portion of the semiconductor chip 503, and the amount of eccentricity is zero at the center of each of the light receiving element arrays 821, 822, 823 and 824. , It is set so that it becomes larger toward the periphery. The eccentric direction is the direction of the line segment connecting the center point of each light receiving element array and each light receiving portion.

FIG. 27 is an enlarged schematic sectional view of the Z region in FIG. 26 (c), and is a view for explaining the action due to the eccentricity of the microlens 516. Light receiving part 821
1, the microlens 5161 is eccentric to the upper side of the drawing, while the microlens 5161 is deviated from the light receiving element 8222.
162 is eccentric to the lower part of the figure. As a result, the light receiving unit 8
The light flux incident on 211 is a region indicated by 8231 by hatching, and the light flux incident on the light receiving unit 8222 is 823.
2 is limited to the hatched area.

Light flux regions 8231 and 8232 are inclined in opposite directions, and are directed toward diaphragm openings 811 and 812, respectively. Therefore, if the amount of eccentricity of the microlens 516 is properly selected, only the light flux emitted from a specific aperture opening will enter each light-receiving element array. That is, the aperture 8 of the diaphragm
The object light passing through 11 is mainly photoelectrically converted by the light receiving element array 821, the object light passing through the aperture 812 of the diaphragm is photoelectrically converted by the light receiving element array 822, and the object light passing through the aperture 813 of the diaphragm is light receiving element array. The object light photoelectrically converted by 823 and further passed through the aperture 814 of the diaphragm is the light receiving element array 82.
It is possible to set the amount of eccentricity so that photoelectric conversion is performed in step 4.

Next, the positional relationship between the object image and the image pickup area and the positional relationship of the pixels when projected onto the subject will be described.
FIG. 28 is a diagram showing the positional relationship between the object image of the compound-eye lens mounted on the imaging module of Embodiment 5 of the present invention and the imaging region. FIG. 29 is a diagram showing the positional relationship of pixels when the image pickup area of FIG. 28 is projected. First, in FIG. 28, 321, 322, 323 and 324 are four light receiving element arrays of the semiconductor chip 503. Here, in order to simplify the description, it is assumed that each of the light receiving element arrays 321, 322, 323, and 324 has 8 × 6 pixels arrayed. The light receiving element arrays 321 and 324 output G image signals, the light receiving element array 322 outputs R image signals, and the light receiving element array 323 outputs B image signals. Pixels in the light receiving element arrays 321 and 324 are shown as white rectangles, pixels in the light receiving element array 322 are shown as hatched rectangles, and pixels in the light receiving element array 323 are shown as black rectangles.

Further, a separation band having a size corresponding to one pixel in the horizontal direction and three pixels in the vertical direction is formed between each light receiving element array. Therefore, the center distance of the light receiving element array that outputs the G image is the same in the horizontal and vertical directions. 351, 35
2, 353 and 354 are object images. Due to the pixel shift, the centers 361, 362, 363 and 364 of the object images 351, 352, 353 and 354 are 1 in the direction from the center of the light receiving element arrays 321, 322, 323 and 324 to the center 320 of the entire light receiving element array. Offset by / 4 pixels.

As a result, when the respective light receiving element arrays are back-projected on the plane at the predetermined distance on the object side, the result is as shown in FIG. Also on the subject side, the light receiving element arrays 321 and 32
The back projection image of the pixels in 4 is a white rectangle 371, the back projection image of the pixels in the light receiving element array 322 is a hatched rectangle 372, and the back projection image of the pixels in the light receiving element array 323 is black. It is shown by a rectangle 373.

The back-projected images of the centers 361, 362, 363 and 364 of the object image overlap as a point 360, and the pixels of the light-receiving element arrays 321, 322, 323 and 324 are inverted so that their centers do not overlap. Projected. The white rectangle outputs the G image signal, the hatched rectangle outputs the R image signal, and the black filled rectangle outputs the R image signal. As a result, the image pickup device having the Bayer array color filter on the subject. The same sampling will be performed.

In comparison with an image pickup system using a single taking lens, if the pixel pitch of the solid-state image pickup element is fixed, 2 × 2 pixels are grouped on the semiconductor chip 503 to form a set of R pixels.
Compared with the Bayer array method in which the GBG color filter is formed, the size of the object image is 1 / √4 in this method. Along with this, the focal length of the taking lens is shortened to about 1 / √4 = 1/2. Therefore, it is extremely suitable for thinning the camera.

Next, a method of manufacturing the image pickup module of this embodiment will be described. The optical elements and the semiconductor chips are bonded at the stage of the semiconductor wafer at the time of the compound eye optical element assembly before the separation, and the spacer assembly is provided between the compound eye optical element assembly and the semiconductor wafer.

FIG. 30 is a top view showing a set of spacers mounted on the image pickup module according to the fifth embodiment of the present invention. In FIG. 30, reference numeral 901 denotes a spacer assembly, which will be divided into two image pickup modules along a dividing line 903 in a later step. In the spacer assembly 901, a plurality of openings are formed in the spacer assembly 901 for guiding the light flux from the optical element to the light receiving element on the semiconductor chip. The optical element assembly further bonded and fixed onto the spacer assembly 901 is also an integrated optical element for two image pickup modules as described later. These pitches are equal to the pitch of semiconductor chips formed on the semiconductor wafer described below. The spacer 522 and the semiconductor chip 503 are bonded with a thermosetting resin. Reference numeral 509 shown in FIG. 26C is a pattern formed by screen printing this thermosetting epoxy resin.

FIG. 31 is a top view of a semiconductor wafer in the manufacturing process of the image pickup module of the present invention. In FIG. 31, reference numeral 910 denotes a semiconductor wafer on which a large number of light receiving element arrays 912 and circuits are provided, which are cut along the outside of the boundary line 911 and connected to an external electric circuit so that each functions as a semiconductor chip. Arrow J indicates the position and moving direction of the dicing blade in the subsequent dicing process.

Here, as described above, the semiconductor wafer 910 is used.
Is a thermosetting resin 913 (the sealing material 50 of FIG. 26C).
(Corresponding to 9) is used to bond the spacer aggregate 901. FIG. 31 shows only one spacer assembly 901.

FIG. 32 is a top view showing a step of attaching a spacer assembly to a semiconductor wafer in the manufacturing process of the image pickup module according to the fifth embodiment of the present invention. Since the spacer does not require a more precise position adjustment than the optical element, the spacer may be provided not for the assembly but for one semiconductor chip.

When the spacer assembly 901 is bonded to the semiconductor wafer 910 as shown in FIG. 32, the optical element assembly 917 is further bonded thereto. At this time, the convex lenses 601, 602, 603 and 604 and the light receiving element array 912 are positioned in a predetermined relationship, and the semiconductor chip 9
The twelfth boundary line 911 and the optical element assembly 917 are arranged and adhered in a predetermined diagonally shifted relationship. By doing so, the surface electrode can be connected to an external electric circuit by a bonding wire. Note that FIG.
In FIG. 2, only one optical element assembly 917 is shown.

In general, since a semiconductor wafer is a crystal,
The electrical, optical, mechanical and chemical properties are anisotropic. Therefore, the pulled ingot is sliced after measuring the plane orientation with high accuracy by a method using X-ray diffraction. Prior to this slice, a linear portion called an orientation flat is formed on a cylindrical ingot in order to show the crystal orientation. 909 shown in FIG.
Is the orientation flat of the semiconductor wafer 910.

At the manufacturing stage of the semiconductor wafer 910, semiconductor element patterns such as the light receiving element array 912 are formed in accordance with the orientation flat 909, while
If a reference pattern is also provided on the compound eye optical element assembly 917 and used for aligning the orientation flat 909 with the reference pattern of the compound eye optical element assembly 917, extremely precise alignment is possible. Moreover, there is a great advantage that the alignment is completed for all of the image pickup modules which are completed by being separated by the subsequent steps by aligning the compound eye optical element assembly 917 and the semiconductor wafer 910 once.

Further, for the adhesion of the compound eye optical element assembly 917, an adhesive (sealing material) 509 of a thermal ultraviolet curing type epoxy resin shown in FIG. 26B is used. The epoxy resin can be suitably used for such applications because it cures slowly, has no unevenness in curing shrinkage, and can relieve stress. There is a type of epoxy resin that is cured by heating, but the reason why the thermal ultraviolet curing type is selected here is that the semiconductor wafer 910 is heated sufficiently to cure the thermosetting epoxy resin. This is suitable because there is no risk of deterioration of the microlenses, the replica portion, or the coating material for printing the diaphragm light-shielding layer 506.

In this bonding step, an epoxy resin (50 shown in FIG. 26B) is formed on the plurality of spacer aggregates 901 bonded on the semiconductor wafer 910 as shown in FIG.
9) is applied, the epoxy resin is semi-cured by ultraviolet irradiation, and then pressed until a predetermined gap is formed,
A small amount of heat treatment is performed to complete curing, and a gap between the optical element assembly 917 and the semiconductor wafer 910 is set,
It is adjusted so that the object image is sharply formed on the light receiving element array 912.

At that time, as shown in FIG. 33, an infrared cut filter having a spectral transmittance characteristic for transmitting ultraviolet rays (about wavelength 300 to 700 nm) is provided around the diaphragm light shielding layer 506 of the compound-eye optical element 512, as shown in FIG. If set,
It is preferable because the epoxy resin can be surely and easily cured by irradiation of ultraviolet rays from the front surface of the semiconductor wafer. As described above, the effect of preventing one-sided blur of the optical image can be expected by fixing the adhesive at the semiconductor wafer stage.

FIG. 34 is a top view showing a step of adhering the compound eye optical element assembly and the semiconductor wafer before the compound eye optical element is separated for one image pickup module in the manufacturing process of the image pickup module of the fifth embodiment of the present invention. Is. The compound eye optical element assembly 917 does not include the same number of optical elements as the semiconductor chips formed on the semiconductor wafer. Here, two sets of convex lenses are formed in the compound-eye optical element assembly 917 shown in FIG. 34, and 11 sets are formed on the semiconductor wafer 910.
The individual compound-eye optical element assembly 917 is fixed. Then, in the subsequent dicing step, each is divided into two compound-eye optical elements to finally obtain 22 image pickup elements. When the size of one compound-eye optical element assembly 917 is set to the maximum size that fits in the effective exposure size of the stepper, the number of imaging modules that can be manufactured from one wafer can be increased, which is advantageous in terms of cost, which is preferable. Is.

As described above, the number of compound eye optical elements formed on the compound eye optical element assembly 917 is made smaller than the number of semiconductor chips formed on the semiconductor wafer 910, and a slight gap is provided between the compound eye optical element assembly. If provided, the flatness of the semiconductor wafer, which has been improved in accuracy by backside adsorption to the jig,
Even if it deteriorates with the release of the suction, the positional relationship between the optical element and the semiconductor chip hardly deteriorates.
In recent years, the tendency for the diameter of semiconductor wafers to become larger has become stronger, but such a configuration is preferable because a high yield rate can be easily obtained.

Semiconductor wafer 910, spacer assembly 90
After the 1 and the compound-eye optical element assembly 917 are fixed, the process moves to a dicing step of cutting the optical element semiconductor wafer bonded body into image pickup modules.

In the dicing process, as described above, for example, Japanese Patent Application Laid-Open No. 11-345785 and Japanese Patent Application Laid-Open No.
The cutting device or laser processing device disclosed in 00-061677 can be used. When cutting is performed using a dicing blade as in JP-A-11-345785, the dicing blade is first controlled along arrow J shown in FIG. Only the semiconductor wafer 910 is cut from the back surface of the wafer 910.

Then, the dicing blade is controlled along the arrow K shown in FIG. 34 to cut only the compound eye optical element from the surface of the compound eye optical element assembly 917. At this time, the dicing marks are grooves formed by etching the optical element assembly 917, metal marks formed by photolithography,
Alternatively, a convex portion of resin formed by a replica is used. In particular, if the replica is formed at the same time as the lens that is the image forming action portion, the manufacturing process can be reduced.

The semiconductor wafer 910, the spacer assembly 901, and the spacer assembly 9 are avoided while avoiding the dicing position.
No. 01 and the optical element assembly 917 are provided with an adhesive layer, the epoxy resin is melted by friction heat with the dicing blade, becomes fine debris, or becomes carbon particles, thereby forming a lens surface. And does not deteriorate the quality of the imaging module.

FIG. 35 is a schematic sectional view of a process of dicing a semiconductor wafer with a dicing blade in the process of manufacturing an image pickup module according to the fifth embodiment of the present invention. In this step, the dicing blade 523 rotates in the direction of the arrow L, which is the direction in which the semiconductor wafer 910 before being cut into the respective semiconductor chips 503 is pressed, but the convex lenses 601 and 60 are temporarily placed on the dicing line.
If there is a resin layer connected to Nos. 2, 603 and 604, a force is applied in the direction of peeling the resin layer from the glass substrate of the compound-eye optical element 512, and the convex lenses 601, 602, 6
The surface precision of 03 and 604 is deteriorated.

In this embodiment, since the resin is removed from the position where the dicing blade passes, the convex lens 60
No unreasonable force is applied to 1, 602, 603, and 604d, and such a problem does not occur. Further, the resin does not melt due to frictional heat with the dicing blade, becomes fine fragments, or becomes carbon particles and adheres to the lens surface, which does not deteriorate the quality of the imaging module.

Each of the above steps is divided into
The imaging module of the present invention shown in FIGS. 6A and 26B is formed.

FIG. 36 is a schematic sectional view showing a connection state and a sealing state between the image pickup module of the fifth embodiment of the present invention and an external electric circuit. In FIG. 36, 517 is a multilayer printed circuit board which is an external electric circuit board, and 520 is an electrode pad 513 (not shown) and a multilayer printed circuit board 517.
A bonding wire 521 for electrically connecting the upper electrode pad is a thermo-UV curable resin for sealing the periphery of the electrode pad 513 and the bonding wire 520. The thermal ultraviolet curable resin 520 is applied over the entire circumference of the image pickup module 511 in order to secure the mounting stability of the image pickup module on the multilayer printed board 517.

In this embodiment, by sealing with the adhesive 509 and another thermo-ultraviolet curable resin 521, deterioration of the microlens 516 and the filter layer due to entry of dust or humidity in the air, or an aluminum layer. It is possible to reliably prevent the electrolytic corrosion of. Moreover, since the sealing can be performed in the semiconductor manufacturing process, the effect is greater. Further, since the surface electrode is connected to the external electric circuit by the bonding wire, the ITO film and the penetrating metal body are not required, and the manufacturing can be performed at low cost. Further, it can be applied to electrical connection using a TAB film without using a bonding wire.

Further, according to this embodiment, in the step of connecting the lens and the semiconductor chip, the active assembly of the image forming lens and the semiconductor chip is not required for each image pickup module, and the process is performed once at the semiconductor wafer stage. Since the alignment with the optical element can be performed, it is possible to significantly reduce the adjustment man-hours.

(Sixth Embodiment) An imaging module according to the sixth embodiment of the present invention will be described with reference to FIGS. 37 to 39. Similar to the first embodiment, the optical element and the semiconductor chip are bonded at the stage of the semiconductor wafer and the optical element assembly before the separation. The optical element assembly is one large light-transmissive plate.

FIG. 37 is a schematic cross-sectional view showing an image pickup module of the sixth embodiment of the present invention, and FIG. 38 is a step of irradiating an optical element semiconductor wafer bonded body with an ultraviolet ray in the manufacturing process of the image pickup module of the sixth embodiment of the present invention. 39 is a schematic cross-sectional view showing the above, and FIG. 39 is a top view of an optical element assembly that is an element constituting the image pickup module of the sixth embodiment of the present invention.

First, in FIG. 37, 165 is an adhesive layer, 161 is a gradient index lens as an image forming section,
Reference numeral 162 denotes an optical element assembly 160, which is a circular stop light-shielding layer formed by offset printing a light-shielding paint on the upper surface of the optical element assembly 160, and 167 is a stop aperture formed in the stop light-shielding layer 162. The semiconductor chip 173 is
The semiconductor wafer 163 is separated from the semiconductor wafer 163 in a later process to form a semiconductor chip 173, which has a large number of electric circuits and light-receiving element arrays. The gradient index lens 161 has an optical path length for forming an object image on the semiconductor wafer 163, and its pitch is equal to the pitch of semiconductor chips formed on the semiconductor wafer.

The parts having the same reference numerals have been described above, and the description thereof will be omitted.

In this embodiment, as shown in FIG. 39, a circular stop light-shielding layer 1 is formed on the upper surface of the optical element assembly 160.
62 is formed by printing a light-shielding paint by, for example, offset printing. Since the light-shielding layer 162 of this embodiment uses an ultraviolet curable resin for the adhesive 165, the adhesive 1
65 is limited to an island shape so that ultraviolet rays can be irradiated from the front of the imaging module. Alternatively, the adhesive 16
If the sheet material or the thermosetting resin does not need to be irradiated with ultraviolet rays as 5, the diaphragm light-shielding layer may not be limited to the island shape.

The present embodiment differs from the fifth embodiment in that a gradient index lens integrated with an optical element of an image pickup module is used as an image forming section. The gradient index lens 161 is a lens having an axially symmetric equirefractive index line, and has a higher refractive index at a position closer to the aperture opening 167.
Equivalently, it can be regarded as a plano-convex lens. This can be manufactured by ion exchange of glass, a method disclosed in JP-A-11-142611, and a method of impregnating a resin layer having a different refractive index into a resin layer. Optical element assembly 160 When borosilicate glass is used for the optical element assembly 160, the difference in linear expansion from the semiconductor wafer is small and it is preferable in terms of stability against temperature changes. In order to prevent the occurrence of defects due to α-rays on the semiconductor wafer, optical glass having a low α-ray surface density may be used. Further, in order to have an infrared ray cutting function, the material may contain an element that absorbs infrared light such as copper ions. The position of the aperture opening 167 in the optical axis direction determines the off-axis chief ray of the optical system, and the aperture position is extremely important in controlling various aberrations. In a lens having a refractive index distribution layer that is convex on the image side, various optical aberrations can be favorably corrected by placing a diaphragm on the light incident surface side. Therefore, the gradient index lens 1 is formed by the light shielding layer 162 on the optical element assembly 160.
A circular aperture opening 167 coaxial with 61 was formed. The main steps until obtaining the image pickup module are the steps of aligning and adhering the semiconductor wafer 163 and the optical element assembly 160, and the steps of dicing and breaking, as in the above-described embodiment.

In the steps of alignment and adhesion, first, the space between the semiconductor wafer 163 and the optical element assembly 160 is filled with an adhesive 165 made of a thermo-ultraviolet curable epoxy resin without forming an air layer to form the optical element assembly. The gap between 160 and the semiconductor wafer 163 is set and adjusted so that the object image is sharply formed. There is a type of epoxy resin that is cured by heating, but the reason why the thermal ultraviolet curing type is selected here is that the semiconductor wafer 163 was heated sufficiently to cure the thermosetting epoxy resin. This is because there is a risk that the color filter, the replica portion, the printing paint for the diaphragm light-shielding layer 162, and the like (not shown) may deteriorate.

Further, as shown by the arrow G in FIG. 38, diffused irradiation of ultraviolet rays is carried out to cure the epoxy resin of the adhesive layer 165 to cure the semiconductor wafer 163 and the optical element assembly 160.
Stick and. At this time, the ultraviolet rays reach the adhesive layer 165 through the transparent area of the optical element assembly 160 (the area where the light shielding layer 162 is not printed in the optical element 160). Moreover, since the diffuse irradiation is performed, the ultraviolet rays reach the adhesive layer 165 below the diaphragm light-shielding layer 162, and the adhesive layer 16
5 can be fully cured.

In the subsequent dicing process, half-cut dicing is performed along the boundary line 166 shown in FIG. In the breaking step following the dicing step, a portion of the semiconductor wafer 163 left uncut by 50 to 100 μm or a portion of the optical element assembly 160 left uncut by 50 to 100 μm is divided using a predetermined roller. Then, if each is connected to an external electric circuit, each functions as an imaging module.

By thus sealing with the adhesive 165, it becomes possible to prevent dust from entering, deterioration of the filter layer due to humidity in the air, and electrolytic corrosion of the aluminum layer. Moreover, since the sealing can be performed in the semiconductor manufacturing process, the effect is greater. In addition, since the alignment with the optical element can be performed at one time at the semiconductor wafer stage, it is possible to significantly reduce the adjustment man-hours.

(Embodiment 7) FIGS. 40 to 46 are views for explaining a compound-eye image pickup module applicable to the distance measuring device and the color image pickup module of the present embodiment.

FIG. 40A is a top view of the image pickup module according to the seventh embodiment of the present invention. 40 (B) is shown in FIG.
It is a typical sectional view in the 40B-40B line of (A). 41 is a top view showing the lower substrate of the image pickup module of the seventh embodiment of the present invention, FIG. 42 is a top view showing the semiconductor chip of the image pickup module of the seventh embodiment of the present invention, and FIG. 42 is an enlarged schematic sectional view of the z region of FIG. 42 to show the function of the microlens in the image pickup module of FIG. 7, and FIG. 44 shows the light receiving element array of the semiconductor chip of the image pickup module of the seventh embodiment of the present invention and the object image. FIG. 45 is a diagram showing the positional relationship, FIG. 45 is a diagram showing the function of the light receiving element array of the image pickup module of the present embodiment, and FIG. 46 is a connection state and sealing of the image pickup module of the seventh embodiment of the present invention and an external electric circuit. It is a typical sectional view showing a stopped state.

In FIG. 40, 501 is an optical element 512.
The upper substrate, 502 is the lower substrate of the optical element 512, 1611
Is the lower substrate 50 for the light passing through the aperture opening 811.
The refractive index distribution type lens as the second lens formed in 2 and the refractive index distribution type lens as the second lens 1613 formed on the lower substrate 502 with respect to the light passing through the aperture 813. Is a bead that defines the thickness of the adhesive 509, and 512 is an optical element composed of an upper substrate 501 and a lower substrate 502.

The parts having the same reference numerals have been described above, and the description thereof will be omitted.

The present embodiment differs from the fifth embodiment in that the elements constituting the optical element 512 are convex lenses 801, 802, 803 and 804 as the first lenses in the present embodiment.
This is that it has an upper substrate on which is formed and a lower substrate 502 on which the gradient index lenses 1611 and 1612 are formed. Reference numerals 811, 813 denote diaphragm apertures. Although not shown, the apertures 812 and 814 are naturally present below the convex lens 802 and the tsu lens 804.

Therefore, the image pickup module of this embodiment is
It has a first compound eye lens formed of a plurality of first lenses and a second compound eye lens formed of a plurality of second lenses.

In the present embodiment, the second lens is formed of a gradient index lens, but it may be formed of an ordinary spherical or aspherical lens like the first lens section. .

The optical element 512 is viewed from above in FIG.
The object light incident on is formed into a plurality of object images on the semiconductor chip 503, and is photoelectrically converted by the light receiving element in the semiconductor chip 503.

The upper substrate 501 has a structure in which a Fresnel lens made of resin is added to the flat glass substrate by the replica manufacturing method. The distance between the lens and the light receiving element array on the semiconductor chip depends on the thickness of the replica layer, and the thickness error of the upper substrate glass and the lower substrate glass is absorbed by the thickness of the replica layer. Alternatively, when the lens portion is made of glass, a method of integrally forming with the substrate may be selected by a method such as glass molding molding, and when the lens portion is resin, injection molding, compression molding or the like.

The first lenses 801, 802, 803 and 804 are circular axially symmetric aspherical Fresnel lenses or spherical Fresnel lenses as shown in FIG. Although the field curvature is satisfactorily corrected, it may be composed of an aspherical lens produced by the replica manufacturing method. In this case, although the optical performance is lower than that of the Fresnel lens, it is relatively easy to manufacture and is advantageous in cost.

On the other hand, the gradient index lenses 1611 and 1
Reference numerals 613 and 1612 and 1614 (not shown) are lenses having an axially symmetric equirefractive index line, which has a higher refractive index at a position closer to a diaphragm aperture described later and can be equivalently regarded as a plano-convex lens. Ion exchange of glass and JP-A-11-14
It can be manufactured by a method of impregnating a resin layer having a different refractive index into a resin layer disclosed in Japanese Patent No. 2611. Also, the first lenses 801, 802, 803 and 804 and the second lenses 1611 and 161 of the gradient index lens.
2, 1613 and 1614 are attached coaxially.

By using the gradient index lens as described above, it is possible to increase the degree of freedom in optical design, and thus it is possible to easily obtain good optical performance as compared with an optical system having a single-lens structure.
Even if the F number is bright, the optical image does not deteriorate, which is preferable. Moreover, since the resolution limit frequency determined by the diffraction of light becomes higher as the lens becomes brighter, an optical system having a higher resolution limit frequency can be obtained. Therefore, it is suitable for the purpose of capturing a high-definition image using the light receiving element array having a small pixel pitch.

In this embodiment, a circular diaphragm light-shielding layer 506 is formed on the upper surface of the lower substrate 502 of the optical element 512 by a light-shielding paint, for example, by offset printing. The diaphragm light-shielding layer 506 is not limited to the island shape when the sheet material or the thermosetting resin is used as the adhesive 165. In this embodiment, an ultraviolet curable resin is used as the adhesive 165. Therefore, in this embodiment, the diaphragm light-shielding layer 506 is the adhesive 1
Since an ultraviolet curable resin is used for 65, it is limited to an island shape. Further, as shown in FIG. 41, a semi-transparent region 5061 may be provided in the peripheral portion of the diaphragm light-shielding layer 506 to make the curing of the sealing material described later more reliable.

The semi-transparent region 5061 can be formed by reducing the print film thickness and suppressing the print area ratio. Alternatively, it may be formed by vapor deposition or sputtering of a thin film such as Inconel, chromel, or chrome. By continuously controlling the position of the shield in the sputtering process, it is possible to control to any transmittance. is there.

The upper substrate 501 and the lower substrate 502 are adhered to each other with a light-transmissive adhesive without any gap so that the interface between the air and the substrate is not formed inside the optical element 512, so that the ghost is generated. To prevent. In addition, this diaphragm light-shielding layer 50
6 may be formed by offset printing a light-shielding paint on the lower surface of the upper substrate 501.

Aperture openings 811, 812, 813 and 81
The position of 4 in the optical axis direction determines the off-axis chief ray of the optical system, and the diaphragm position is extremely important in controlling various aberrations. For an image forming section consisting of a gradient index lens element convex to the image side equivalent to a Fresnel surface convex to the object side, various optical aberrations can be corrected well by placing a stop inside the image forming section. It is possible and preferable. Therefore, as shown in FIG.
The two light blocking layers 506 provide four circular aperture openings 811;
812, 813, and 814 were formed.

Further, the diaphragm openings 811, 812, 813.
Color filters that transmit only light in a specific wavelength range are formed inside the and 814 by screen printing. Green transmission through the apertures 811 and 814 (G)
A red transmission (R) filter is inside the filter and the aperture opening 812, and a blue transmission (B) filter is inside the aperture opening 813. Since there is a thin transparent adhesive layer between the color filter and the upper substrate 501, even if the color filter is arranged on the diaphragm surface, the flatness of the color filter hardly poses a problem, and it can be manufactured by printing.

Here, the lens units 801, 802, 803
And 804, aperture openings 811, 812, 813, and 814, and gradient index lens units 1611 and 1612.
The combined optical performance of 1613 and 1614 is optimized for each color of the color filter. Specifically, the shapes of the lens units 801, 802, 803 and 804 and the aperture diameters of the aperture openings 811, 812, 813 and 814 are slightly different depending on the color of the color filter, that is, the transmission wavelength of the color filter. Distributed lens unit 1
The refractive index distribution states of 611, 1612, 1613 and 1614 are all the same. The lens unit 8
Shapes of 01, 802, 803, and 804 and diaphragm aperture 81
Since the respective differences in the opening diameters of 1, 812, 813 and 814 are so slight, this difference is not shown in the drawings in this specification.

A lens portion (manufactured by molding) and a diaphragm aperture (manufactured by printing) that are relatively easy to manufacture with high precision.
Since the optical performance for optimizing the color filter for each color is provided and the optical performances of the gradient index lens portions are all the same, there is an effect of improving the production yield of the imaging module.

Incidentally, the reason why the optical performance of the image pickup optical system is optimized for each color of the color filter in this way is to perform the Bayer array image generation by pixel shift described later with high accuracy. It is disclosed in the image pickup device described in Japanese Patent Publication No. 78123.

It is manufactured by pouring black resin into the groove formed by half-cut dicing the lower substrate 502.
Further, in order to have an infrared ray cutting function, an element that absorbs infrared light such as copper ions is included in the material of both or one of the upper and lower substrates 501 and 502.

As shown in FIG. 42, the semiconductor chip 503.
Four object images of RGBG are formed on the upper side by the optical element 512, and these are photoelectrically converted by the light receiving element arrays 821, 822, 823, 824 provided on the semiconductor chip,
Capture as an electric signal. Light receiving element array 8 shown in FIG.
Reference numerals 21, 822, 823, and 824 are arrays in which a large number of pixels are arranged in a two-dimensional direction. Light receiving element array 821, 822
Each of the light receiving elements b, 823, and 824 is a microlens 5
16 to improve the light collection efficiency.

Furthermore, the microlens 516 is arranged so as to be eccentric with respect to the light receiving portion of the semiconductor chip 503, and the amount of eccentricity is zero at the center of each light receiving element array 821, 822, 823, and becomes larger toward the periphery. Is set. In addition, the eccentric direction is defined by the light receiving element arrays 821, 822,
This is the direction of the line segment connecting the central point of 823 and each light receiving unit.
FIG. 43 is a schematic cross-sectional view in which the Z region in FIG. 42 (c) is enlarged, and is a diagram for explaining the action due to the eccentricity of the microlens 516. The microlens 5161 is decentered upward in the figure with respect to the light receiving portion 8211, while the microlens 5162 is decentered downward in the figure with respect to the light receiving element 8222. As a result, the light beam incident on the light receiving unit 8211 is limited to the area indicated by hatching 8231, and the light beam incident on the light receiving unit 8222 is limited to the region indicated by hatching 8232.

The light flux regions 8231 and 8232 are inclined in opposite directions, and are directed toward the aperture openings 811 and 812, respectively. Therefore, if the amount of eccentricity of the microlens 516 is properly selected, only the light flux emitted from a specific aperture opening will enter each light-receiving element array. That is, the aperture 8 of the diaphragm
The object light passing through 11 is mainly photoelectrically converted by the light receiving element array 821, the object light passing through the aperture 812 of the diaphragm is photoelectrically converted by the light receiving element array 822, and the object light passing through the aperture 813 of the diaphragm is light receiving element array. The object light photoelectrically converted by 823 and further passed through the aperture 814 of the diaphragm is the light receiving element array 82.
It is possible to set the amount of eccentricity so that photoelectric conversion is performed in step 4.

Next, the positional relationship between the object image and the image pickup area, and the positional relationship of the pixels when projected onto the subject will be described.
44 and 45 are diagrams showing the relationship. First, in FIG. 44, 321, 322, 323 and 324 are four light receiving element arrays of the semiconductor chip 503. Here, in order to simplify the description, the light receiving element arrays 321, 322,
It is assumed that each of 323 and 324 has 8 × 6 pixels arrayed. The light receiving element arrays 321 and 324 output G image signals, the light receiving element array 322 outputs R image signals, and the light receiving element array 323 outputs B image signals. The pixels in the light-receiving element arrays 321 and 324 are white rectangles, and
Pixels inside are rectangles with hatching, and light receiving element array 3
Pixels within 23 are indicated by black rectangles.

Further, a separation band having a size corresponding to one pixel in the horizontal direction and three pixels in the vertical direction is formed between each light receiving element array. Therefore, the center distance of the light receiving element array that outputs the G image is the same in the horizontal and vertical directions. 351, 35
2, 353 and 354 are object images. Due to the pixel shift, the centers 361, 362, 363 and 364 of the object images 351, 352, 353 and 354 are 1 in the direction from the center of the light receiving element arrays 321, 322, 323 and 324 to the center 320 of the entire light receiving element array. Offset by / 4 pixels.

As a result, when the respective light receiving element arrays are back projected onto the plane at the predetermined distance on the object side, the result is as shown in FIG. Also on the subject side, the light receiving element arrays 321 and 32
The back projection image of the pixels in 4 is a white rectangle 371, the back projection image of the pixels in the light receiving element array 322 is a hatched rectangle 372, and the back projection image of the pixels in the light receiving element array 323 is black. It is shown by a rectangle 373.

The back-projected images of the centers 361, 362, 363 and 364 of the object image overlap as a point 360, and the pixels of the light-receiving element arrays 321, 322, 323 and 324 are reversed so that their centers do not overlap. Projected. The white rectangle outputs the G image signal, the hatched rectangle outputs the R image signal, and the black rectangle draws the R image signal. As a result, the image pickup device having the Bayer array color filter on the subject The same sampling will be performed.

In comparison with an image pickup system using a single taking lens, considering the pixel pitch of the solid-state image pickup element to be fixed, 2 × 2 pixels are grouped on the semiconductor chip 503 to form an RG.
Compared with the Bayer array method in which the BG color filter is formed, the size of the object image is 1 / √4 in this method. Along with this, the focal length of the taking lens is shortened to about 1 / √4 = 1/2. Therefore, it is extremely suitable for thinning the camera.

Now, returning to the structure of the image pickup module, the optical element 512 and the semiconductor chip 503 are bonded with a thermo-ultraviolet curing type resin. Reference numeral 509 shown in FIG. 42 is a seal material pattern formed by screen-printing a thermal ultraviolet curing epoxy resin. For example, beads 510 having a diameter of 6 μm are dispersed in the sealing material, and the optical element 512
509 that forms a gap between the semiconductor chip 503 and the semiconductor chip 503.
Of the bead 510 is accurately set so that the object image is sharply formed on the light receiving element arrays 821, 822, 823 and 824. Since this gap can be strictly controlled, the microlens 516 does not come into contact with the substrate 502, and the microlens 516 improves the light-collecting efficiency, so that an image pickup module that can easily pick up an image of a low-luminance object can be provided. Become.

The material of the beads 510 can be selected from organic polymers and quartz, but in the case of quartz beads, it is possible to destroy the protective film, electrodes, or switching elements formed on the semiconductor wafer in the pressing process for gap formation. It is more preferable that the organic polymer has the property that the pressurizing condition in the pressing step can be wide.

Further, FIG. 47 is a schematic sectional view showing an image pickup module having another structure in the seventh embodiment of the present invention. As shown in the image pickup module of FIG. 47, a spacer 222 is formed under the sealing material, and a sealing material 223 containing no beads or the like is thinly laid on the spacer 222, so that the gap between the optical element 512 and the semiconductor chip 503 is reduced. You can do the precision soup. In this case, the same material as the microlens is used, and the spacer 222 can be simultaneously formed in the microlens forming step.

If no beads are used, an organic polymer is used as the material of the beads 510, or if the pressurizing conditions in the pressing process are optimized even with quartz, the circuit of the semiconductor chip 503 will be as shown in FIG. You may arrange | position a sealing material on it.

When the circuit portion and the seal portion are overlapped on the semiconductor chip as described above, the chip area can be reduced, which is very advantageous in terms of cost.

Epoxy resin is suitable for this application because it cures slowly, has no unevenness in curing shrinkage, and relaxes stress. Note that some epoxy resins are hardened by heating, but the reason why the thermal ultraviolet curing type is selected here is that the semiconductor chip 503 is heated sufficiently to cure the thermosetting epoxy resin. This is because the microlens 516 and the diaphragm light-shielding layer 506 may deteriorate the printing paint, the color filter, and the like.

In this bonding step, the optical element 512 is diagonally shifted and stacked on the semiconductor chip 503, the epoxy resin of the adhesive 509 is semi-cured by ultraviolet irradiation, and then the gap corresponding to the diameter of the beads 510 is obtained. Are pressed until they are formed, and a slight heat treatment is performed to complete the curing.

At this time, since the transparent region 5061 is formed in the peripheral portion of the light shielding layer 506 of the lower substrate 502 as described above, the epoxy resin of the adhesive 509 is removed by irradiating ultraviolet rays from the front of the semiconductor chip 503. It can be easily and reliably cured. The transparent region 502a needs to be transparent to ultraviolet rays, and may be opaque to light of other wavelengths.

When the image pickup module 211 obtained by the above-described steps is viewed from the main surface direction of the upper substrate 501, it is as shown in FIG. 40A, and the semiconductor chip 503 can be seen in the back of the upper substrate 501. The electrode pads 513 are located on two sides of the semiconductor chip 503.

FIG. 46 is a schematic sectional view showing a connection state and a sealing state between the image pickup module of this embodiment and an external electric circuit. In this embodiment, the bonding wire 5 is formed by connecting the electrode pad 513 (not shown) formed on the semiconductor chip 503 and the electrode pad on the multilayer printed board 517.
Connect electrically at 20.

When the thermal ultraviolet curing resin 521 is cured, ultraviolet irradiation is mainly performed from the front of the image pickup module.
In order to prevent the electrode pad 513 of the semiconductor chip 503 from corroding, the side surface of the lower substrate 502 and the thermo-ultraviolet curable resin 521 are used.
Adhesion with is extremely important.

When the range of the diaphragm light-shielding layer 506 is not limited to the inside of the adhesive 509, the thermal ultraviolet curable resin 5 is used.
The ultraviolet rays reach the sealing portion of the lower substrate 502 through the layer 21 and the ultraviolet rays reach the sealing portion of the lower substrate 502, so that this portion is the last to be cured. However, in this imaging module, the range of the diaphragm light-shielding layer 506 is set inside the adhesive 509. Due to the limitation, there is an optical path of ultraviolet rays to the sealing portion of the lower substrate 502 indicated by the arrow G, and this optical path does not pass through the layer of the thermal ultraviolet curable resin 521, and the thermal ultraviolet curable resin 521 is not passed through. It is possible to surely cure and seal 221. Moreover, since the semi-transparent region in which the light-shielding layer is not printed is provided in the peripheral portion of the diaphragm light-shielding layer 506, although the light intensity is low, the optical path of the arrow Ga also exists, so that curing and sealing can be performed more reliably. it can.

Further, not only the arrow H but also the optical path of Ha exists, and high mounting stability to the multilayer printed board 517 can be obtained.

By thus sealing with the adhesive 509 and the thermal ultraviolet-curing resin 521, deterioration of the microlens 516 and the filter layer due to ingress of dust and humidity in the air, or electrolytic corrosion of the aluminum layer is prevented. It is possible to surely prevent it. Moreover, since the graded index lens on the flat plate is used, the semiconductor chip 503 can be easily sealed.

Since the surface electrode is connected to the external electric circuit by the bonding wire, the ITO film and the penetrating metal body are not required, and the manufacturing can be performed at low cost. Further, it can be applied to electrical connection using a TAB film without using a bonding wire.

In the present embodiment, the case where the subject is separated into three colors of R, G, and B to be imaged and the color images are combined is described. Therefore, the first compound-eye lens is optimized for each color. 2 types of optical performance
Although the compound-eye lenses have been described by using the image pickup device configured to have the same optical performance, for example, the subject is decomposed into the luminance signal and the color signal or the G signal and the R and B signals. Applied to a known two-plate type image pickup device that picks up an image and synthesizes a color image, the first compound eye lens has two types of optical performances optimized for each of a luminance signal and a color signal, or a G signal and R and B signals. The second compound eye lenses may be image pickup modules configured to have the same optical performance.

A method of manufacturing the image pickup module of this embodiment will be described with reference to FIGS. 48 to 51. In this embodiment, the optical element 512 and the semiconductor chip are bonded to the optical element assembly at the stage before the separation and the semiconductor wafer, respectively.

FIG. 48 is a top view showing the upper substrate assembly in the manufacturing process of the image pickup module according to the seventh embodiment of the present invention.
49 is a top view of the lower substrate assembly in the manufacturing process of the image pickup module of the seventh embodiment of the present invention, and FIG. 50 is a top view of the semiconductor wafer in the manufacturing process of the image pickup module of the seventh embodiment of the present invention. FIG. 51 is a top view showing a step of separating the image pickup module from the optical element semiconductor wafer bonded body in the process of manufacturing the image pickup module according to the seventh embodiment of the present invention.

First, in FIG. 48, reference numeral 717 denotes an upper substrate assembly of an optical element assembly, which is divided into two upper substrates 501 for two image pickup modules in a later step. In FIG. 49, reference numeral 714 denotes a lower substrate assembly of the optical element assembly, and the upper substrate assembly 717 and the lower substrate assembly 714 are adhered to each other with a light-transmissive adhesive without any gap, thereby forming an optical plate-shaped optical member. It becomes an element assembly. Then, these pitches are equal to the pitch of the semiconductor chips formed on the semiconductor wafer described below. A semiconductor wafer 710 shown in FIG. 51 is provided with a large number of light-receiving element arrays 712 and circuits by a known process, and is cut along the outside of a boundary line 711 and connected to an external electric circuit, whereby each semiconductor chip Function as. In FIG. 51, arrow B indicates the position and moving direction of the dicing blade in the subsequent dicing process. Further, the semiconductor wafer 710 has an ultraviolet curing epoxy resin as an adhesive 713 formed by screen printing, and the optical element assembly and the semiconductor wafer 710 are bonded using this epoxy resin. FIG. 50 shows only one optical element assembly 719.

In this case, there is an extremely great advantage that the alignment of the optical element assembly 719 and the semiconductor wafer 710 is completed once, and the alignment is completed for all of the image pickup modules which are separated and completed in the subsequent steps.

In this adhesion step, as shown in FIG. 50, the epoxy resin formed on the semiconductor wafer 710 is semi-cured by irradiation of ultraviolet rays, and then pressed until a predetermined gap is formed, and a slight heat treatment is performed. Complete curing is performed, a gap between the optical element assembly 719 and the semiconductor wafer 710 is set, and adjustment is performed so that an object image is sharply formed on the light receiving element array 712.

When the bonding of all the optical element assemblies 719 is completed, it becomes as shown in FIG.

The optical element assembly 719 is the semiconductor wafer 71.
It does not have the same number of optical elements as the semiconductor chips 503 formed on the optical disc. Here, two sets of convex lenses are formed in the optical element assembly 719 shown in FIG.
Eleven optical element aggregates 719 are fixed onto 10 and divided into two optical elements in the subsequent dicing step to finally obtain 22 image pickup elements. If the size of one optical element assembly 719 is set to the maximum size that fits within the effective exposure size of the stepper, the number of imaging modules that can be manufactured from one wafer can be increased, which is advantageous in terms of cost.

As described above, the number of optical elements 512 formed on the optical element assembly 719 is made smaller than the number of semiconductor chips formed on the semiconductor wafer 710, and a slight gap is provided between the optical element assemblies. In this case, even if the flatness of the semiconductor wafer, which has been improved in accuracy by the back surface suction on the jig, deteriorates with the release of the suction, the positional relationship between the optical element and the semiconductor chip is hardly deteriorated. Recently, the tendency for the diameter of a semiconductor wafer to become larger has become stronger, but with such a structure, a high yield rate can be easily obtained. Note that a large-sized optical element assembly having the same number of optical elements as the total number of semiconductor chips of the semiconductor wafer 710 may be used.

Semiconductor wafer 710, optical element assembly 71
After 9 is fixed, the process moves to a dicing process for cutting the optical element semiconductor wafer bonded body into image pickup modules.
For dicing semiconductor wafers, glass substrates, or resin substrates, for example, JP-A-11-345785 and JP-A-2
The cutting apparatus or laser processing apparatus disclosed in Japanese Patent Publication No. 000-061677 is used. When performing cutting using a dicing blade like the former,
While cooling by applying cutting water, first, the arrow B shown in FIG.
By controlling the dicing blade along the semiconductor wafer 7
Only the semiconductor wafer 710 is cut from the back surface of 10.

Next, the dicing blade is controlled along the arrow I shown in FIG. 51 to cut only the optical element assembly 719 from the surface of the optical element assembly 719.

At this time, the dicing marks are grooves formed by etching the optical element assembly 719, metal marks formed by photolithography technique, or resin protrusions formed by replica. In particular, if the replica is formed at the same time as the lens that is the image forming action portion, the manufacturing process can be reduced.

Since the adhesive layer for adhering the semiconductor wafer 710 and the optical element assembly 719 is provided while avoiding the dicing position, the epoxy resin is melted by frictional heat with the dicing blade or becomes fine fragments. It does not occur that the quality of the image pickup module is deteriorated by being attached to the lens surface by forming carbon particles or carbon particles.

Further, since the replica resin is removed from the position where the dicing blade passes, no unreasonable force is applied and distortion or stress is not generated in the lens portion. The process is divided into the above steps to obtain the imaging module of the embodiment shown in FIGS. 40A and 40B.

At this time, in the dicing process, since the cutting is performed by shifting the phase from the front and back, the pad portion for the bonding wire can also be exposed as shown in FIG. 40 (A), and connection with the subsequent electric circuit. The process can also be facilitated.

According to this embodiment, the imaging lenses 801, 802, 803 and 804 and the semiconductor chip 50 are also included.
In the process of connecting the semiconductor wafer 3 and the image pickup module 3, the active assembly of the imaging lens and the semiconductor chip 503 is not required for each image pickup module, and the alignment with the optical element can be performed at one time at the stage of the semiconductor wafer 710. Therefore, the number of adjustment steps can be greatly reduced, which is more preferable.

(Embodiment 8) In this embodiment, an image pickup module having an improved light shielding property will be described with reference to FIGS. 52 and 53.

FIG. 52 is a top view of the image pickup module of the eighth embodiment of the present invention, and FIG. 53 is the image pickup module 53 of FIG.
It is a schematic cross section in the line -53.

In FIG. 52, reference numeral 224 designates a light shielding plate having a sufficient light shielding property for the wavelength range received by the light receiving element array.

The parts having the same reference numerals have been described above, and the description thereof will be omitted. Note that the present embodiment is different from the seventh embodiment in that the image pickup module of the present embodiment is provided with a light shielding plate 224 in order to enhance the light shielding property.

The light shielding plate 224 is shown in FIGS.
It is formed by being fixedly attached to the upper surface of the imaging module of the seventh embodiment described above using (B).

The light blocking plate 224 has two openings 500 and 600.
With convex lenses 801 and 802 in the opening 500,
Convex lenses 803 and 804 are located in the opening 600, respectively. Convex lenses 801, 802 on the upper substrate 501,
By shielding the portions other than 803 and 804 as much as possible, it is possible to prevent the generation of stray light incident from the outside of the diaphragm light-shielding layer 506.

(Embodiment 9) In this embodiment, Embodiment 1
An imaging device using the imaging modules 8 to 8 will be described.

The image pickup apparatus described in this embodiment is characterized in that it is made thin using the compound eye optical element described in Embodiment 7.

54 (A), 54 (B), and 54.
FIG. 54C is a diagram showing the entire digital color camera having the image pickup module according to the present invention, and FIG.
54B is a side view seen from the left side of the backside view 54A, and FIG. 54C is a sideview seen from the right side of the backside view 54A. 55 is a schematic sectional view taken along line 55-55 of the digital color camera shown in FIG. 54. In the present embodiment, a digital color camera equipped with a color filter is taken as an example, but a digital camera without a color filter may of course be used.

In FIG. 54, reference numeral 401 is a card type camera body, 405 is a main switch, 406 is a release button, 407 is a switch for the user to set the state of the camera, and 410 is a display section for the remaining number of shootable images. Is. Reference numeral 411 denotes a viewfinder eyepiece window through which the object light incident on the viewfinder exits. Reference numeral 412 is a standardized connection terminal for connecting to an external computer or the like and transmitting / receiving data, 423 is a contact protection cover,
Reference numeral 211 denotes an image pickup module located inside. The camera body 401 may have the same size as the PC card and may be mounted on the personal computer. In this case, the length is 85.6 mm, the width is 54.0 mm, and the thickness is 3.3 mm (P
C card standard Type 1) or 5.0 mm (PC card standard Type 2). Note that this embodiment only shows an example of a digital color camera, and the functions of the digital color camera are not limited to this embodiment.

In FIG. 55, 414 is a housing for holding each component of the camera, 415 is a back cover, 211 is an image pickup module, 416 is a switch which is turned on when the release button 406 is pressed, and 420 is protective glass. is there. The protective glass 420 is provided with a transparent coating to avoid the generation of ghosts. Furthermore, in order to reduce the incidence of light from outside the imaging range on the imaging module 211 as much as possible, the cover 421 for blocking light is provided in the area other than the effective portion.
Is provided. The switch 416 is a release button 406.
It has a first-stage circuit that closes when is pressed down by half and a second-stage circuit that closes when pressed down to the end.

Reference numerals 418 and 419 are first and second prisms forming a finder optical system. The first and second prisms 418 and 419 are formed of a transparent material such as acrylic resin, and both have the same refractive index. In addition, it is in a state of being buried so that the light ray goes straight inside.
It utilizes the total internal reflection of light that occurs in the air gap between the first and second prisms to act as a finder.

Further, a light shielding plate 422 is provided between the protective glass 420 and the image pickup module 211 in order to prevent stray light from being generated through a transparent region around the diaphragm light shielding layer 506 in the image pickup module 211, and a housing is provided. It is fixed to 414.

Like the light-shielding plate 224 of the seventh embodiment, the light-shielding plate 422 is provided with openings for taking in object light in the lens portions 801, 802, 803 and 804.
The incidence of light from other than this is prevented. Therefore, an extremely sharp image without stray light can be taken with such a digital color camera.

Next, an example in which the image pickup module of each of the above-described embodiments is applied to a still camera is shown in FIG.
This will be described using 6. FIG. 56 is a block diagram showing a case where the image pickup module of the present invention is applied to a "still video camera".

In FIG. 56, 1101 is a barrier which also serves as a lens switch and a main switch, 1102 is a lens for forming an optical image of a subject on a solid-state image sensor 1104, and 1103 is an aperture for limiting the amount of light passing through the lens 1102. Reference numeral 1104 denotes a solid-state image sensor for taking in the subject formed by the lens 1102 as an image signal. Lens 1102, aperture 1103, solid-state image sensor 11
Reference numeral 04 constitutes an image pickup module. Reference numeral 1106 denotes an A / D converter that performs analog-digital conversion of the image signal output from the solid-state image sensor 1104, and 1107 performs various corrections on the image data output from the A / D converter 1106 and compresses the data. A signal processing unit 1108, a solid-state imaging device 1104, an imaging signal processing circuit 1105, A
A timing generator that outputs various timing signals to the D / D converter 1106 and the signal processor 1107 is an overall control that controls various operations and the entire still video camera.
An arithmetic unit 1110 is a memory unit for temporarily storing image data, 1111 is an interface unit for recording or reading on a recording medium, and 1112 is a detachable semiconductor memory or the like for recording or reading image data. A possible recording medium 1113 is an interface unit for communicating with an external computer or the like.

Next, the operation of the still video camera at the time of shooting in the above-mentioned structure will be described.

When the barrier 1101 is opened, the main power source is turned on, then the control power source is turned on, and further, the image pickup system circuits such as the A / D converter 1106 are turned on.

Then, in order to control the exposure amount, the overall control / arithmetic unit 1109 controls the accumulation time of the solid-state image pickup device 1104. The signal output from the solid-state image sensor 4 is A
After being converted by the / D converter 1106, the signal processing unit 110
Input to 7. The overall control / calculation unit 1109 calculates the exposure based on the data.

The brightness is determined based on the result of the photometry, and the overall control / calculation unit 1109 controls the accumulation time again according to the result.

Then, after the proper exposure amount is confirmed, the main exposure is started. When the exposure is completed, the solid-state image sensor 110
The image signal output from the A.D.
The signal is converted to −D and is written in the memory through the signal processing unit 1107 and the overall control / calculation 1109. Thereafter, the data accumulated in the memory unit 1110 is recorded on the removable recording medium 1112 such as a semiconductor memory through the recording medium control I / F unit under the control of the overall control / arithmetic unit 1109. Further, the image may be processed by directly inputting it to a computer or the like through the external I / F unit 1113.

Furthermore, it may be so arranged that a moving picture is recorded.

[Brief description of drawings]

1A is a schematic cross-sectional view of an image pickup module according to a first embodiment of the present invention, and FIG. 1B is a schematic cross-sectional view showing another configuration of the image pickup module of the present invention.

FIG. 2A is a top view of an upper substrate which is an element constituting an optical element of the image pickup module according to the first embodiment of the present invention;
(B) is a top view of a lower substrate which is an element constituting an optical element of the image pickup module of Embodiment 1 of the present invention, and (C) is a top view showing a semiconductor chip of the image pickup module of Embodiment 1 of the present invention. Is.

FIG. 3 is a schematic cross-sectional view of the semiconductor chip at the position of line 3-3 shown in FIG. 2 (C).

FIG. 4 is a schematic cross-sectional view showing the incident direction of light with respect to the image pickup module according to the first embodiment of the present invention.

FIG. 5 is a top view of the upper substrate assembly in the manufacturing process of the imaging module according to the first embodiment of the present invention.

FIG. 6 is a top view of the lower substrate assembly in the manufacturing process of the imaging module according to the first embodiment of the present invention.

FIG. 7 is a top view of the semiconductor wafer in the manufacturing process of the imaging module according to the first embodiment of the present invention.

FIG. 8 is a schematic cross-sectional view of the adhesive curing process in the manufacturing process of the imaging module according to the first embodiment of the present invention.

9A is a top view showing a step of separating the imaging module from the optical element semiconductor wafer bonded body in the manufacturing process of the imaging module of Embodiment 1 of the present invention, and FIG. 9B is a line 9B-9B in FIG. 9A. 3 is a schematic cross-sectional view showing a cross section in FIG.

FIG. 10 is a top view in which two convex lenses are formed on the upper substrate aggregate.

FIG. 11 is a schematic cross-sectional view showing a dicing step of the optical element semiconductor wafer bonded body in the manufacturing process of the imaging module of the first embodiment of the present invention.

FIG. 12 is a schematic sectional view of an image pickup module according to a second embodiment of the present invention.

FIG. 13A is a top view of a lower substrate which is an element constituting an optical element of the image pickup module according to the second embodiment of the present invention;
FIG. 7B is a top view showing a semiconductor chip of the image pickup module according to the second embodiment of the present invention.

FIG. 14 is a top view of the semiconductor wafer when the optical element assembly and the semiconductor wafer are bonded together in the manufacturing process of the imaging module according to the second embodiment of the present invention.

15A is a top view showing a lower substrate of an image pickup module of Embodiment 3 of the present invention, and FIG. 15B is a top view showing a semiconductor chip of the image pickup module of Embodiment 3 of the present invention.

FIG. 16 is a top view of the lower substrate assembly in the manufacturing process of the imaging module according to the third embodiment of the present invention.

FIG. 17 is a top view of the semiconductor wafer in the manufacturing process of the imaging module according to the third embodiment of the present invention.

FIG. 18 is a top view of the upper substrate assembly in the manufacturing process of the imaging module according to the third embodiment of the present invention.

19 is a schematic cross-sectional view taken along the line 19-19 in FIG.

FIG. 20 is a schematic cross-sectional view showing a dicing process of an optical element / semiconductor wafer bonded body in the manufacturing process of the imaging module of the third embodiment of the present invention.

FIG. 21 is a top view of the image pickup module according to the third embodiment of the present invention.

22 is a schematic cross-sectional view taken along line 22-22 of the imaging module in FIG.

FIG. 23 is a schematic cross-sectional view showing a connected state and a sealed state between the image pickup module and the external electric circuit according to the third embodiment of the present invention.

FIG. 24 is a schematic cross-sectional view showing a step of irradiating an optical element semiconductor wafer bonded body with an ultraviolet ray in the manufacturing process of the imaging module of the fourth embodiment of the present invention.

FIG. 25 is a schematic cross-sectional view showing an image pickup module according to a fourth embodiment of the present invention.

26A is a top view of the image pickup module according to the fifth embodiment of the present invention, FIG. 26B is a schematic cross-sectional view taken along the line 26B-26B of FIG. 26A, and FIG. 5 is a top view of a semiconductor chip, which is one element of the image pickup module of FIG.

27 is a schematic cross-sectional view enlarging the Z region in FIG. 26 (c).

FIG. 28 is a diagram showing a positional relationship between an object image of a compound eye lens mounted on an image pickup module according to a fifth embodiment of the present invention and an image pickup area.

FIG. 29 is a diagram showing a positional relationship of pixels when the imaging region of FIG. 28 is projected.

FIG. 30 is a top view showing an aggregate of spacers mounted on the imaging module according to the fifth embodiment of the present invention.

FIG. 31 is a top view of the semiconductor wafer in the manufacturing process of the imaging module according to the fifth embodiment of the present invention.

FIG. 32 is a top view showing a step of attaching a spacer assembly to a semiconductor wafer in the manufacturing process of the imaging module according to the fifth embodiment of the present invention.

FIG. 33 is a diagram showing a spectral transmittance characteristic of an infrared cut filter.

FIG. 34 is a top view showing a step of adhering the compound eye optical element assembly and the semiconductor wafer before the compound eye optical element is separated for one image pickup module in the manufacturing process of the image pickup module according to the fifth embodiment of the present invention. .

FIG. 35 is a schematic cross-sectional view of a process of dicing a semiconductor wafer with a dicing blade in the process of manufacturing the image pickup module according to the fifth embodiment of the present invention.

FIG. 36 is a schematic cross-sectional view showing a connected state and a sealed state between the image pickup module and the external electric circuit according to the fifth embodiment of the present invention.

FIG. 37 is a schematic sectional view showing an image pickup module according to the sixth embodiment of the present invention.

FIG. 38 is a schematic cross-sectional view showing a step of irradiating an optical element-semiconductor wafer bonded body with an ultraviolet ray in the manufacturing process of the imaging module of the sixth embodiment of the present invention.

FIG. 39 is a top view of an optical element assembly which is one element of the image pickup module according to the sixth embodiment of the present invention.

40A is a top view of the image pickup module of Embodiment 7 of the present invention, and FIG. 40B is a schematic cross-sectional view taken along line 40B-40B of FIG. 40A.

FIG. 41 is a top view showing the lower substrate of the imaging module of the seventh embodiment of the present invention.

FIG. 42 is a top view showing a semiconductor chip of the image pickup module according to the seventh embodiment of the present invention.

FIG. 43 is a schematic cross-sectional view in which the z region in FIG. 42 is enlarged to show the function of the microlens in the imaging module of the seventh embodiment of the present invention.

FIG. 44 is a diagram showing a positional relationship between the light receiving element array of the semiconductor chip of the image pickup module of the seventh embodiment of the present invention and an object image.

FIG. 45 is a diagram showing the function of the light-receiving element array of the imaging module according to the seventh embodiment of the present invention.

FIG. 46 is a schematic cross-sectional view showing a connected state and a sealed state between the image pickup module and the external electric circuit according to the seventh embodiment of the present invention.

FIG. 47 is a schematic cross-sectional view showing an image pickup module having another configuration according to the seventh embodiment of the present invention.

FIG. 48 is a top view of the upper substrate assembly in the manufacturing process of the imaging module according to the seventh embodiment of the present invention.

FIG. 49 is a top view of the lower substrate assembly in the manufacturing process of the imaging module according to the seventh embodiment of the present invention.

FIG. 50 is a top view of the semiconductor wafer in the manufacturing process of the imaging module according to the seventh embodiment of the present invention.

FIG. 51 is a top view showing a step of separating the image pickup module from the optical element semiconductor wafer bonded body in the process of manufacturing the image pickup module according to the seventh embodiment of the present invention.

FIG. 52 is a top view of the image pickup module according to the eighth embodiment of the present invention.

53 is a schematic cross-sectional view taken along the line 53-53 of the imaging module in FIG. 52.

54 (A), (B) and (C) are views showing the entire digital color camera having the image pickup module of the present invention.

55 is a schematic cross-sectional view taken along line 55-55 of the digital color camera shown in FIG. 54.

FIG. 56 is a block diagram showing a case where the image pickup module of the present invention is applied to a “still video camera”.

57A is a schematic cross-sectional view of a conventional image pickup module, and FIG. 57B is a top view showing a light shielding member of the conventional image pickup module.

58A to 58E are schematic cross-sectional views showing the manufacturing process of the conventional imaging module.

59 (F) to (H) are schematic cross-sectional views showing the manufacturing process of the conventional imaging module.

FIG. 60 is a top view of a conventional transparent substrate (glass substrate) on which a plurality of semiconductor chips are mounted.

FIG. 61 is a perspective view of an image pickup module using a conventional gradient index lens.

[Explanation of symbols] 101 upper substrate 102 lower substrate 103 Aperture shield layer 104 semiconductor chip 107 optical element 100 convex lens 200 aperture

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4M118 AA05 AA10 AB01 AB10 GB01                       GB11 GB19 GC08 GC11 GD02                       GD03 GD04 GD07 GD09 GD10                       HA03 HA05 HA24 HA26 HA27                       HA29 HA30 HA33                 5F088 BA15 BA16 BB03 CB17 JA12                       JA13 JA20

Claims (15)

[Claims] 1. A semiconductor chip having a light-receiving element array,
In an imaging module having an optical element for guiding light onto the light-receiving element array, the optical element includes an image forming action section and a light-shielding layer, and is between the semiconductor chip and the optical element. An ultraviolet-curable resin formed at a position avoiding the light-shielding layer with respect to the incident direction of, and the optical element and the semiconductor chip are fixed to each other via the ultraviolet-curable resin. Image pickup module. 2. The image pickup module according to claim 1, wherein an opening for letting out an internal pressure is formed in a part of the adhesive formed on the semiconductor chip. 3. The optical element and the semiconductor chip are adhered to each other with a constant gap in one direction or two directions, and an electrode pad for electrical connection to the outside is formed at an upper open position of the semiconductor chip. The image pickup module according to claim 1, wherein the image pickup module is provided. 4. The optical element is a compound eye optical element including a plurality of the image forming action sections.
The imaging module according to. 5. A digital camera having the image pickup module according to claim 1 mounted therein. 6. A semiconductor chip having a light-receiving element array,
In a method of manufacturing an image pickup module having an imaging element and an optical element having a light-shielding layer, the optical element assembly and a semiconductor wafer provided with a plurality of light-receiving element arrays are shielded in the light incident direction. An image pickup module comprising: a step of adhering with an adhesive formed at a position avoiding layers, a step of curing the adhesive, and a step of dicing at a position avoiding the imaging action portion. Manufacturing method. 7. The dicing step is performed on a region where the adhesive is avoided, a region where a surface resin portion of the optical element is formed thinner than other resin portions, or a surface of the optical element. The method of manufacturing an image pickup module according to claim 6, which is a step of dicing along the groove. 8. An image pickup module having an optical element provided on a semiconductor chip, wherein the optical element includes a first lens and a second lens, and the second lens is the first lens. An imaging module, which is provided correspondingly. 9. The image pickup module according to claim 8, wherein the second lens is a gradient index lens. 10. The optical element is configured by bonding an upper substrate and a lower substrate to each other, the first lens is formed on the upper substrate, and the second lens is formed on the lower substrate. The imaging module according to claim 8, wherein 11. The image pickup module according to claim 8, wherein an optical axis of the first lens and an optical axis of the second lens are adjusted coaxially. 12. The optical element includes a first compound eye lens formed of a plurality of the first lenses, and a plurality of the second eye lenses.
9. The image pickup module according to claim 8, wherein the image pickup module is a compound eye optical element having a second compound eye lens formed from the lens of claim 9. 13. An imaging module having a semiconductor chip having a light receiving element array and an optical element for guiding light onto the light receiving element array, wherein the optical element is a light blocking layer, a first lens and a first lens. A second lens corresponding to the lens, the ultraviolet curing resin formed between the semiconductor chip and the optical element and at a position avoiding the light shielding layer in the incident direction of light. An image pickup module, characterized in that the optical element and the semiconductor chip are fixed to each other via the ultraviolet curable resin. 14. The image pickup module according to claim 13, wherein the second lens is a gradient index lens. 15. The optical element comprises a first compound eye lens formed of a plurality of the first lenses, and a plurality of the second compound lenses.
14. The image pickup module according to claim 13, wherein the image pickup module is a compound eye optical element having a second compound eye lens formed from the lens of claim 13.