JPH11177074A - Solid-state imaging device - Google Patents

Abstract

(57) [Summary] A burr is formed on an outer surface of a solid-state imaging device to cause poor appearance. A substrate 1 having a concave portion 1a for accommodating a solid-state imaging device 3 on its upper surface, made of a thermoplastic resin having a deflection temperature under load of 200 ° C. or more, and formed by injection molding, and an inside of the concave portion 1a. A plurality of lead terminals 4 led out from the outside, the solid-state imaging device 3 housed in the concave portion 1a of the base 1, and the upper surface of the base 1 are joined to the upper surface of the base 1 via a sealing material 7, and the concave portion 1a The sealing member 7 is formed of an organic resin having an elastic modulus of 5 GPa or less, and is provided in the recess 1a in a region where the lead terminal 4 is led out. Material 6 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a solid-state image pickup device in which a solid-state image pickup device is hermetically accommodated in a solid-state image pickup device storage package.

[0002]

2. Description of the Related Art Conventionally, a solid-state image pickup device is formed by hermetically containing a solid-state image pickup device in a package for accommodating the solid-state image pickup device. Specifically, first, a solid-state image pickup device is made of a thermosetting resin such as an epoxy resin. A base having a concave portion for mounting and housing the solid-state imaging element on the upper surface, a plurality of lead terminals having an inner end exposed inside the concave portion of the base and an outer end protruding outside the base; A package for housing a solid-state imaging device is provided, comprising a translucent glass lid attached to the upper surface via a sealing material made of epoxy resin and closing the concave portion of the base. The solid-state imaging device is bonded and fixed to the bottom surface of the recess provided in the base of the storage package via a resin adhesive such as epoxy resin, and each electrode of the solid-state imaging device is bonded to the inner end of the lead terminal by a bonding wire. Via electrically connected to, thereafter,
It is manufactured by bonding a lid made of translucent glass to the upper surface of the base via a sealing material made of epoxy resin and hermetically housing the solid-state imaging device inside a container consisting of the base and the lid. .

In such a solid-state image pickup device, a plurality of lead terminals protruding outside a package for accommodating a solid-state image pickup device are connected to an external electric circuit. The solid-state image sensor is irradiated with a target image via a cover made of translucent glass to form an image, and the solid-state image sensor performs photoelectric conversion to function as an imaging device such as a video camera.

Incidentally, as a base of a package for accommodating a solid-state imaging device used in the solid-state imaging device, generally, dimensional accuracy can be increased, and a lead terminal, a sealing material,
It is formed by using an epoxy resin that has excellent adhesion to solid-state imaging devices and has excellent mechanical strength, environmental resistance, and excellent electrical insulation. Method), that is, an epoxy resin precursor is injected from an injection port into the inside of a resin molding die composed of two split dies,
Cured at a temperature of 80 ° C. for 2 to 4 minutes, then removed from the mold, post-cured in an oven at a temperature of about 50 ° C., and heat-cured the epoxy resin precursor to produce a predetermined shape. I have.

[0005]

However, in this conventional solid-state imaging device, the base of the package for housing the solid-state imaging device is formed of an epoxy resin, and the epoxy resin is cured for a long time of 2 to 4 minutes. During the cure, a part of the epoxy resin precursor enters the mating portion of the split mold, and burrs are formed on the inner and outer surfaces. There was a disadvantage that the portion was covered with burrs and the bonding wire could not be connected.

It is also conceivable to remove burrs that cause the appearance defect by a water jet or the like. However, when the burrs are removed by a water jet or the like,
Part of the burrs becomes fine powder and adheres to the concave portion of the base, which adheres to the surface of the solid-state imaging device housed in the concave portion of the base, and the solid-state imaging device has an accurate optical image corresponding to an external optical image. The disadvantage that photoelectric conversion cannot be caused is induced.

Further, when the substrate is manufactured by the transfer molding method, a post-curing step of heating for a long time while maintaining a constant temperature is required. As a result, mass productivity is extremely poor, and a solid-state imaging device as a product is expensive. There was also a drawback that it would be.

The present invention has been devised in view of the above-mentioned drawbacks, and has as its object to surely and firmly electrically connect each electrode of a semiconductor element to a lead terminal without causing an appearance defect.
An object of the present invention is to provide an inexpensive solid-state imaging device capable of causing a solid-state imaging device to perform accurate photoelectric conversion corresponding to an external optical image.

[0009]

The solid-state imaging device according to the present invention has a concave portion for accommodating a solid-state imaging element on an upper surface thereof.
A base made of a thermoplastic resin having a deflection temperature under load of 200 ° C. or higher, formed by injection molding, a plurality of lead terminals led from the inside to the outside of the recess, and a solid housed in the recess of the base. An image sensor, and a lid made of a translucent glass that is joined to the upper surface of the base via a sealing material and seals the recess, wherein the sealing material has an elastic modulus of 5;
It is formed of an organic resin of GPa or less, and a moisture-proof material is provided in a region of the concave portion from which the lead terminal extends.

The solid-state imaging device according to the present invention is characterized in that the substrate is formed of polyphenylene sulfide or a liquid crystal polymer of a hot-melt type.

Further, in the solid-state imaging device according to the present invention, the encapsulating material may contain 5 to 50% by weight of acrylic resin particles in an epoxy resin.
It is characterized by being formed to contain.

Still further, in the solid-state imaging device according to the present invention, the moisture-proof material is formed by adding 10 to 80% by weight of silica powder to epoxy resin.

According to the solid-state imaging device of the present invention, the base of the package for housing the solid-state imaging device is formed of a thermoplastic resin having a short curing time. A part of the plastic resin does not enter the mating portion of the resin molding die to form burrs on the inner and outer surfaces. As a result, appearance defects caused by the burrs can be effectively prevented and lead terminals can be prevented. Is not covered with burrs, and the bonding wires connected to the respective electrodes of the semiconductor element can be securely and firmly connected to the lead terminals.

Further, since burrs which cause poor appearance and the like are not formed on the inner and outer surfaces of the substrate, a process for removing the burrs is not performed. A part of the removed burrs does not enter into the concave portion of the substrate. As a result, it is possible to cause the solid-state imaging device to perform accurate photoelectric conversion corresponding to an external optical image.

Furthermore, when the substrate is manufactured by the injection molding method, the thermoplastic resin is cooled and solidified in a mold in a short time, so that the mass productivity of the substrate is extremely excellent, and the solid-state imaging device as a product is inexpensive. Can be made.

[0016]

Next, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows an embodiment of a solid-state imaging device according to the present invention, in which 1 is a base, and 2 is a lid made of translucent glass. The base 1 and the lid 2 constitute a container for housing the solid-state imaging device 3.

The base 1 has a concave portion 1a for mounting a solid-state image sensor at the center of the upper surface thereof, and the solid-state image sensor 3 is provided on the bottom surface of the concave portion 1a with a resin adhesive such as epoxy resin. It is adhesively fixed.

The substrate 1 has a deflection temperature under load of 200 ° C.
It is formed of the above thermoplastic resin, specifically, polyphenylene sulfide, a liquid crystal polymer of a hot-melt type, or the like. Inject the thermoplastic resin softened by heating from the injection port of the resin molding die that has been combined, and then cool it,
It is manufactured by curing.

The deflection temperature under load is defined as ASTM.
(American Standard of Test Method) D648, temperature measured specifically, width 13mm,
A thermoplastic resin having a length of 127 mm and a thickness of 3 mm was prepared as a test piece, and the temperature was raised while a load of 1.82 MPa was applied to the center of the test piece. Say.

The substrate 1 manufactured by the injection molding method (injection molding method) has a short curing time of about 10 to 50 seconds for the thermoplastic resin injected into the resin molding die. Part enters the mating part of the resin molding die, and burrs are formed on the inner and outer surfaces of the base 1,
The burr does not cause the appearance defect, and the burr does not cover the inner end of the lead terminal 4 described later, and does not hinder the connection between the inner end of the lead terminal 4 and the bonding wire 5.

Further, since no burrs which cause poor appearance are not formed on the outer surface of the base 1, a step for removing the burrs is not required.
Of the solid-state imaging device 3, which will not be able to cause accurate photoelectric conversion in the solid-state imaging device 3.

Further, when the substrate 1 is manufactured by the injection molding method (injection molding method), since the thermoplastic resin is cooled and solidified in a mold in a short time, the mass productivity of the substrate 1 is extremely excellent.

If the deflection temperature under load of the substrate 1 made of the thermoplastic resin is less than 200 ° C., the solid-state image sensor 3 is connected to an external electric circuit when the solid-state image sensor 3 is bonded and fixed to the bottom surface of the concave portion 1a. When heat is applied during the operation or when the solid-state imaging device 3 is operated, the substrate 1 may be softened and deformed, and the function as the solid-state imaging device may be lost. Therefore, the substrate 1 has a deflection temperature under load of 200.
Specified above ° C.

If the substrate 1 made of the thermoplastic resin is formed of polyphenylene sulfide or a liquid crystal polymer of a heat melting type, the polyphenylene sulfide,
The hot-melt type liquid crystal polymer has a small shrinkage ratio during transfer molding (injection molding), can improve dimensional accuracy, is excellent in mechanical strength, and is an acid, an alkali, or an organic solvent such as acetone, xylene, or alcohol. It is preferably used because it has a property of being excellent in corrosion resistance.

Further, when a heat-melting liquid crystal polymer is used as the substrate 1, a monomer appropriately selected from aromatic dicarboxylic acids, aromatic diols, hydroxyaromatic carboxylic acids and the like is combined, and these are subjected to an esterification reaction. A polyester liquid crystal monomer composed of a polymer obtained by polymerization is preferably used.

A plurality of lead terminals 4 extending from the inside to the outside of the recess 1a are attached to the base 1 having a recess 1a for accommodating the solid-state imaging device 2 on the upper surface.

The lead terminals 4 serve to electrically connect the respective electrodes of the solid-state image sensor 3 to a predetermined external electric circuit. Are electrically connected via a bonding wire 5, and a region led out of the concave portion 1a is electrically connected to an external electric circuit via solder or the like.

The lead terminal 4 is made of, for example, a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy, and is subjected to a suitable rolling process or punching process on an ingot made of an iron-nickel-cobalt alloy or the like. By applying, it is formed in a predetermined shape.

When the lead terminal 4 is manufactured by injecting a thermoplastic resin into a resin molding die to manufacture the base 1, the lead terminal 4 is set at a predetermined position of the resin molding die in advance. At the predetermined position of the base 1, it is attached so as to be drawn out from the inside to the outside of the concave portion 1 a.

The base 1 to which the lead terminals 4 are attached
Further, a moisture-proof material 6 is disposed in a region where the lead terminal 4 extends inside the concave portion 1a.

The moisture-proof material 6 has a function of effectively preventing moisture in the atmosphere from entering the recess 1a through the joint interface between the base 1 and the lead terminal 4. For example, the moisture-absorbing material may be added to the epoxy resin. Is formed so as to adsorb water that is going to enter the recess 1a through the bonding interface between the base 1 and the lead terminal 4 to the silica powder.

The moisture-proof material 6, for example, is obtained by dropping an epoxy resin precursor containing silica powder as a moisture-absorbing material into a region where the lead terminal 4 is led out inside the concave portion 1a.
This is heat-treated at a temperature of about 150 ° C., and the epoxy resin precursor is thermally cured, so that the epoxy resin precursor is disposed inside the recess 1 a in a region from which the lead terminal 4 extends.

When the moisture-proof material 6 is formed by adding silica powder as a moisture-absorbing material to an epoxy resin, if the content of the silica powder is less than 10% by weight, the moisture contained in the atmosphere will be reduced to the substrate 1 It is not possible to effectively prevent an attempt to enter the recess 1a through the bonding interface with the lead terminal 4, and if it exceeds 80% by weight, the thixotropy of the moisture-proof material 6 becomes too strong and the fluidity is lost. In addition, it is difficult to appropriately dispose the moisture proof material 6 in the region where the lead terminal 4 is led out inside the concave portion 1a. Therefore, when the moisture-proof material 6 is formed by adding silica powder as a moisture-absorbing material to an epoxy resin, the content of the silica powder is 10 to 10.
It is preferable to set it in the range of 80% by weight.

Further, the base 1 on which the lead terminals 4 are attached
The lid 2 made of translucent glass is provided on the upper surface with a sealing material 7.
The solid-state imaging device 3 is hermetically accommodated in a container including the base 1 and the lid 2 by closing the recess 1 a of the base 1 with the lid 2.

The cover 2 is made of, for example, a light-transmitting glass such as borosilicate glass or soda glass. The cover 2 hermetically closes the concave portion 1a of the base 1 and also allows an external optical image to be formed in the concave portion 1a. And functions as a window member for irradiating and imaging the solid-state imaging device 3.

The sealing material 7 for attaching the lid 2 to the base 1 is an organic resin having an elastic modulus of 5 GPa or less, for example, an epoxy resin containing acrylic rubber particles. The epoxy resin precursor containing acrylic rubber particles is disposed between the base 1 and the lid 2 and then heat-treated at a temperature of about 150 ° C.
Substrate 1 by thermosetting epoxy resin precursor
And the lid 2 are joined via a sealing material 7.

When the sealing material 7 is formed of an epoxy resin containing particles of acrylic rubber, the hardness of the sealing material 7 is reduced and the elastic force is increased, whereby the thermal expansion of the base 1 and the lid 2 is achieved. This is because it is possible to absorb the stress generated due to the difference in the coefficient. If the sealing material 7 is formed of an epoxy resin containing particles of acrylic rubber, the base 1 is made of a thermoplastic resin, The body 2 is formed of a translucent glass such as borosilicate glass or soda glass, and even if stress is generated between the two due to a difference in the coefficient of thermal expansion between the two, the stress will deform the sealing material 7. As a result, the base 1 and the lid 2 are securely joined to each other via the sealing material 7, and the inside of the container 4 including the base 1 and the lid 2 is always airtightly sealed. It is possible to keep.

The sealing material 7 has an elastic modulus of 5 GP.
If it exceeds a, the sealing material 7 becomes too hard, and it becomes impossible to favorably absorb the stress generated between the base 1 and the lid 2. Therefore, the sealing material 7 has an elastic modulus of 5 GPa.
It is specified below.

When the sealing material 7 is formed of an epoxy resin containing acrylic rubber particles, the elastic modulus of the sealing material 7 exceeds 5 GPa when the amount of the acrylic rubber particles is less than 5% by weight. Since the hardness becomes high, the stress generated between the base 1 and the lid 2 cannot be favorably absorbed, and if it exceeds 50% by weight, the fluidity of the sealing material 7 is greatly reduced, There is a risk that it is difficult to uniformly interpose the stopper 7 between the base 1 and the lid 2, and the reliability of hermetic sealing of the container may be reduced. Therefore, the sealing material 7
Is formed of an epoxy resin containing acrylic rubber particles, the amount of the acrylic rubber particles is preferably set in the range of 5 to 50% by weight.

Further, when the sealing material 7 is formed of an epoxy resin containing particles of acrylic rubber, when the particle size of the acrylic rubber particles becomes 0.1 μm, the particles of the acrylic rubber aggregate to form In this case, the hardness of the sealing material 7 becomes high, so that the stress generated between the base 1 and the lid 2 cannot be favorably absorbed. When joining the base 1 and the lid 2 with the sealing material 7, the thickness of the sealing material 7 becomes unnecessarily large, and moisture and the like easily enter. Therefore, when the sealing material 7 is formed of an epoxy resin containing acrylic rubber particles, the particle size of the acrylic rubber particles is 0.1 to 2
It is preferable to keep the range of μm.

Thus, the solid-state imaging device 3 is bonded and fixed to the bottom surface of the concave portion 1a of the base 1 with an adhesive made of a resin such as epoxy resin, and each electrode of the solid-state imaging device 3 is connected to the lead terminal 4 via the bonding wire 6. Electrically connected to
Thereafter, a cover 2 made of translucent glass is provided on the upper surface of the base 1.
Are joined via a sealing material 7, and the solid-state imaging device 3 is hermetically accommodated in a container formed of the base 1 and the lid 2, thereby forming a solid-state imaging device as a product.

In such a solid-state imaging device, a plurality of lead terminals 4 protruding outside the package for accommodating the solid-state imaging device are connected to a predetermined external electric circuit, and each electrode of the solid-state imaging device 3 housed inside is connected to the external electric circuit. Connected and irradiates and forms an optical image on the solid-state imaging device 3 through the lid 2,
By causing the solid-state imaging device 3 to perform photoelectric conversion, it functions as an imaging device such as a video camera.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

[0044]

According to the solid-state imaging device of the present invention, since the base of the package for storing the solid-state imaging device is formed of a thermoplastic resin having a short curing time, the base is formed by injection molding (injection molding). In addition, a part of the thermoplastic resin does not enter the mating portion of the resin molding die and burrs are not formed on the inner and outer surfaces, and as a result, the appearance defect caused by the burrs can be effectively prevented and The inner end of the lead terminal is not covered with burrs, and the bonding wire connected to each electrode of the semiconductor element can be securely and firmly connected to the lead terminal.

Further, since no burrs which cause poor appearance or the like are formed on the inner and outer surfaces of the substrate, a step for removing the burrs is not performed. A part of the removed burrs does not enter into the concave portion of the substrate. As a result, it is possible to cause the solid-state imaging device to perform accurate photoelectric conversion corresponding to an external optical image.

Further, when the substrate is manufactured by the injection molding method, the thermoplastic resin is cooled and solidified in a mold in a short time, so that the mass productivity of the substrate is extremely excellent, and the solid-state imaging device as a product is inexpensive. Can be made.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a solid-state imaging device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base 2 ... Lid 3 ... Solid-state imaging device 4 ... Lead terminal 6 ... ·····················································

Claims (4)

[Claims] 1. A base made of a thermoplastic resin having a deflection temperature under load of 200 ° C. or more and having a concave portion for accommodating a solid-state imaging device on an upper surface, and a base formed by injection molding, and from inside to outside of the concave portion. A plurality of lead terminals derived,
The solid-state imaging device housed in the concave portion of the base, and a lid made of translucent glass that is joined to the upper surface of the base via a sealing material and seals the concave portion, wherein the sealing material is elastic. A solid-state imaging device, which is formed of an organic resin having a rate of 5 GPa or less, and wherein a moisture-proof material is provided in a region of the recess from which a lead terminal extends. 2. The solid-state imaging device according to claim 1, wherein said substrate is formed of polyphenylene sulfide or a liquid crystal polymer of a hot-melt type. 3. The solid-state imaging device according to claim 1, wherein the sealing material is formed by adding 5 to 50% by weight of acrylic rubber particles to an epoxy resin. 4. The solid-state imaging device according to claim 1, wherein said moisture-proof material is formed by adding 10 to 80% by weight of silica powder to epoxy resin.