JPH06286782A - Integrated-circuit case - Google Patents

Abstract

PURPOSE:To satisfy all performance requirements of electrical conductivity, transparency and heat resistance by specifically regulating a case body for specifically regulating a light transmittance, haze and deflection temperature under load and the volume resistivity value. primary particle diameter and content of conductive fine particles dispersed as coating of the case body in a matrix layer. CONSTITUTION:This apparatus is provided with an almost tube- or plate-shaped integrated-circuit case body 1 for containing many integrated circuits composed of rigid material having 75% or more light transmittance per 1mm thickness, 8% and less haze and 150 degrees or higher deflection temperature under load. Also, the apparatus is equipped with conductive layers 2 covering the inner and outer surfaces of the case body 1. The conductive layers 2 are equipped with conductive fine particles 21 dispersed in a matrix layer 22 composed of resin binder and having 10<2>OMEGAcm and less volume resistivity value and 0.2mum and less primary particle diameter. The content of the conductive fine particles 21 is 60-75 pts.wt., when the total of the resin binder and conductive fine particles is 100 pts.wt., and the conductive fine particles 21 come out to the surfaces of the conductive layers 2. Therefore, it is possible to bake the fine particles without impairing their quality.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated circuit case, and more specifically, it heats and dehydrates (bakes) the water contained in the encapsulant after sealing the IC chip with a resin, and then ships in that state. The present invention relates to a case for IC baking and shipping for integrated circuits.

[0002]

2. Description of the Related Art An IC is subjected to a sealing agent treatment (package sealing) for protecting the IC chip after heat welding (bonding) to the lead frame of the IC chip. Epoxy resins have been the mainstream as the sealing agent used for this purpose, but this resin has the drawback of high water absorption. Therefore, the encapsulant easily absorbs moisture, and this moisture is vaporized by heat of about 200 ° C. applied in the soldering process (solder reflow process) performed after the IC is mounted on the printed board, and the sealant is sealed. There were many problems (so-called package crack trouble) that cracks occurred in the stopper (reference document; Nikkei New Material, No. 5).
3, 41, 1988). In particular, QFP (Quad
A logic IC called a Flat Package)
Since the degree of integration is high and the number of lead frames is large, the encapsulant itself inevitably becomes thin and the above-mentioned troubles are likely to occur. For this reason, this type of IC is baked on an individual dedicated tray at a temperature of about 120 to 130 ° C. for about 24 hours before being mounted on a printed circuit board, and is baked to remove moisture in the sealant. Is removed and used. In recent years, mainly in Europe and the United States, there is a tendency to perform baking at a temperature of 150 ° C. or higher for 4 to 6 hours for the purpose of improving the reliability of the baking and shortening the baking time. An integrated circuit case (IC tray) having high heat resistance and high conductivity is being proposed (Japanese Patent Laid-Open No. 2-166082, Reference: USP 510).
4581).

On the other hand, DIP (Dual Inline)
The IC group centered on memory, such as package), has a small number of lead frames and has been considered to be unrelated to the above-mentioned package cracks from the past. In order to reduce the size of electronic devices, the thickness of the encapsulant has been reduced, and it is inevitable that baking is performed at a temperature of 130 to 150 ° C. for 5 to 24 hours. Therefore, under these circumstances,
It is desirable to improve the work efficiency of IC producers and users by carrying out the baking process while the IC is stored in the integrated circuit case used for transportation. For this purpose, the integrated circuit case has conductivity (surface electric resistance; 10 ⁹ Ω) for preventing discharge damage of the stored IC chip.
The following conductivity is required, and transparency is required to confirm the status of the IC inside the integrated circuit case from the outside.
It is necessary to have heat resistance that can withstand the above baking even when the IC is stored in the integrated circuit case.

However, the fact is that an integrated circuit case that satisfies all of the above-mentioned required performances at the same time, can be easily manufactured, and is suitable for mass production has not yet been proposed. For example, in the case of an integrated circuit in which the inner surface and the outer surface of an integrated circuit case body (extrusion tube etc.) made of a transparent soft resin such as polystyrene resin or polyvinyl chloride resin is coated with an antistatic surfactant,
It does not have enough heat resistance to satisfy the above baking conditions. Further, in this case, even when the integrated circuit case body is made of another resin material having transparency and heat resistance, the surface-active agent coated on the surface thereof is present only in the presence of a small amount of water. Since the antistatic effect is generated, the antistatic effect disappears due to the loss of water due to the baking. On the other hand, instead of the above-mentioned surfactant, a method of coating a conductive metal by plating, vapor deposition or sputtering, or a case body for integrated circuits is made of inorganic glass, and a metal coating film is formed on the surface thereof. The integrated circuit case manufactured by the method simultaneously satisfies all of the above-mentioned required performances, but these methods result in poor productivity and high cost.

Therefore, under the present circumstances, the IC producer side or the like stores the IC in an aluminum extraction tube or the like for baking as a first step, and then conducts a conductive coating on the surface with a surfactant as a second step. The baked IC is placed in an integrated circuit case made of polystyrene
It is in a situation where it takes a lot of labor to refill the product, and if necessary, attach a rubber or plastic stopper plug before shipping. Further, the epoxy resin sealant has a reversible water absorbing action, and after the IC is exposed to the outside air after shipping, the water absorbing state before baking is recovered in about 100 hours (reference document; mounting technique).
vol. 8, No. 1, p. 74). Therefore, on the side of the IC user, when using an IC which is not used due to production activities or the like and is redundant, it is necessary to perform baking under the conditions presented by the IC manufacturer. . For this reason, even the user of the IC is still spending unnecessary labor such as transferring to the aluminum tube, baking, and refilling with the resin tube for use.

[0006]

SUMMARY OF THE INVENTION The present invention eliminates the unnecessary labor in the above-mentioned production activities, is beneficial to both IC producers and users, and enables efficient production, transportation and use of ICs. It is an object of the present invention to provide an integrated circuit case capable of establishing a system for the purpose.

[0007]

The integrated circuit case (hereinafter referred to as "case") of the first invention is a JISK71.
The light transmittance (hereinafter, referred to as "light transmittance") per 1 mm in thickness based on the 05 test method is 75% or more, and the haze value (hereinafter, referred to as "haze value") per 1 mm in thickness is 8.
% Or less, and further, a deflection temperature under load (hereinafter referred to as “deflection temperature under load”) based on JISK7202A test method is made of a hard resin material of 150 ° C. or higher, and is substantially tubular or substantially dish-shaped to accommodate a large number of integrated circuits. Of the integrated circuit case body, and a conductive layer covering the inner surface and the outer surface of the case body, the conductive layer being a base material layer made of a resin binder, and the volume resistivity value dispersed in the base material layer. Is 10 ² Ω
cm or less and a primary particle diameter of 0.2 μm or less, and the content of the conductive fine particles is 6 when the total amount of the resin binder and the conductive fine particles is 100 parts by weight.
It is 0 to 75 parts by weight, and the conductive fine particles are exposed on the surface of the conductive layer.

The above-mentioned "light transmittance" and "cloudiness value" are required for the case main body so that if the case has such a degree of transparency, even if a predetermined conductive layer is coated and formed, the inside of the case is The characters printed on the surface of the IC can be identified, and quality control in the transportation, mounting, baking process, etc. can be appropriately performed while the IC is housed in the case. In order to perform such quality control more simply and appropriately, the light transmittance is 80% or more,
In addition, the haze value is preferably 5% or less.

The reason why the above "deflection temperature under load" is required for the case body is as follows. That is, if the case body does not have sufficient heat resistance (shape stability, dimensional stability, etc.) that can withstand the baking process, the case body is greatly deformed and it becomes difficult to take out the IC from the case. Or, the IC may be damaged. Further, it is considered that such deterioration and deterioration due to heat may adversely affect the transparency, which is another required performance of the case body. Further, particularly during baking, the resin and the conductive layer forming the case body are softened due to the high temperature, and the case body is likely to be thermally deformed when the stored state of the IC is uneven, and the coating film "Indulgence"
This may cause a damaged state, and a continuous insulating portion may be generated in the case body. Further, the reason why the heat resistance is judged by the "deflection temperature under load" is that it is considered to be optimum for the evaluation of shape stability, dimensional stability and the like at a high temperature of 150 ° C or higher. The reason why the temperature is set to 150 ° C. or higher is that IC baking is usually performed at 130 to 150 ° C. (or higher temperature). The "deflection temperature under load" is preferably 160 ° C or higher when the baking process is performed for a long time.

As the resin material forming the case body, as shown in the third aspect of the present invention, a resin having excellent heat resistance such as polysulfone resin, polyethersulfone resin, polyphenylsulfone resin or polyarylate resin and capable of being molded. Is preferably used. Also, the above "case body"
The shape of “is substantially tubular or substantially dish-shaped” means that the case of the present invention is a case for DIP (mainly substantially tubular)
Not limited to, the case for QFP (mainly a tray in the shape of a plate)
It is also intended to be used as.

As described above, the reason why the primary particle diameter of the conductive fine particles is 0.2 μm or less is that the transparency of the conductive layer itself is good and the transparency of the entire case is not impaired. That is, in general, in order for the coating film to have transparency, the particle diameter of the coating particles contained is required to be half or less of 0.4 to 0.8 μm, which is the wavelength range of visible light. Considering the apparent increase in the particle size due to the secondary agglomeration of the coating particles, it is necessary to set the particle size to a quarter or less of the wavelength of visible light. Then, when such conductive fine particles are dispersed in the base material layer made of a transparent resin binder to form a conductive layer, sufficient transparency can be secured.

As the above-mentioned "conductive fine particles", as shown in the fourth aspect of the present invention, the substrate is composed of barium sulfate particles, and the surface of the substrate is formed by coating, and the surface is doped with indium oxide or antimony oxide. It may be composed of a tin oxide coating. This is because in order to ensure the “transparency” of the conductive layer, it is preferable to take into consideration the characteristics such as color tone and refractive index of the conductive fine particles. That is, fine particles obtained by doping antimony oxide on the surface of a substrate made of titanium oxide, zinc oxide particles, etc., which are commonly used as conductive fine particles, have conductivity but have high light hiding power, and the coating film is whitened. Tend to do. On the other hand, the conductive fine particles listed in the fourth aspect of the present invention can ensure sufficient transparency. It should be noted that the tin oxide coating does not necessarily have to be doped with the indium oxide or the like as long as a predetermined conductivity can be secured. As the conductive fine particles, a tin oxide substrate surface doped with antimony oxide or the like can be used, but in this case, the surface may be discolored greenish black.

The thickness of the conductive layer is preferably 2 μm or less from the viewpoint of ensuring the transparency, but it is preferably 1 μm or less if the transparency is further emphasized. However, by making the primary particle diameter of the conductive fine particles small (for example, 0.1 μm or less), sufficient transparency can be secured even when the film thickness is large (for example, about 3 μm). The transparency of the case where the conductive layer is formed is
Light transmittance of 70% or more (more preferably 75% or more) based on JISK7105 test method, and haze value of 25%
The following is preferable. This is because the necessary transparency can be secured.

As described above, it is necessary to determine the "volume resistivity value" and the "content" of the conductive fine particles and to "display the surface of the conductive layer" by the conductive fine particles. For the reason. That is, in order for the conductive layer to fully exhibit the antistatic function and prevent the discharge breakdown of the IC, its surface electric resistance must be 10 ⁹ Ω or less. On the other hand, in the cross-sectional situation of the conductive layer on the surface of the case body, as shown in FIG. 3, a part of the conductive fine particles 21 is exposed on the surface layer of the coating film (conductive layer) 2, and further, the conductive fine particles are inside the coating film. 21 is fixed by the resin binder 22, and the conductive fine particles 21 are also continuously connected. As a result, antistatic performance is exhibited on the surface of the case. Incidentally, as shown in the figure, it is possible to dispose mainly particles 21 having a relatively large particle size on the lower layer side and relatively fine particles 211 on the surface side. Also, the volume resistivity has a certain value (10 ² Ωc
By containing a certain amount (62 to 73 parts by weight) of the conductive fine particles of m or less, sufficient conductivity can be secured. The conductive layer is a layer having conductivity,
It is sufficient if it has at least an antistatic property.

Another reason for determining the "content" of the conductive fine particles in this way is to secure a certain amount or more of the resin binder constituting the base material layer of the conductive layer, and to secure the conductive fine particles with this binder. This is to prevent the conductive layer from easily falling off from the surface of the case body by hardening. The conductive layer can be formed, for example, by immersing the case main body in an antistatic coating liquid (conductive coating liquid) whose viscosity has been adjusted, then pulling it up and drying it. Furthermore, in order to adjust the film thickness, it may be dried again after being immersed in the antistatic coating liquid. In addition, this conductive layer,
Not only on the inner surface of the case body, but also on the outer surface,
This is because it is necessary to prevent generation of static electricity not only between the case body and the IC but also between the case bodies during transportation.

Further, as the "resin binder" constituting the base material layer, an acrylic resin binder having a glass transition temperature of 60 ° C. or higher can be used. This type of resin has very good light transmittance, and when diluted with a solvent, the viscosity decreases to an appropriate level, and it is easy to form a thin film of about several μm. Further, even if it is a thin film with a thickness of about several μm, the acrylic resin inherently holds the conductive fine particles sufficiently, so that even if the IC chip slides or vibrates in the case, the coated particles may fall off. The damage of the coating film can be prevented. Further, the hard resin material used for the case body in the present invention generally has low surface activity, low wettability with a coating film, and has poor solvent resistance such that it slightly swells in ketones, toluenes, etc. Therefore, it is possible to use an acrylic resin type and a room temperature dry type in which the solvent diluent thereof is easily dried and solidified after being applied to the case body.
An acrylic resin-based baking type that is heat-curable can also be used, which is preferable from the viewpoint of heat resistance. However, if this coating film thickness is too large, the curing shrinkage force of the coating film will have Since the adhesion to the case body is exceeded, the adhesion with the resin forming the case body is deteriorated after the baking step, and the coating film may peel off, it is preferable to reduce the film thickness.

Further, as shown in the second aspect of the present invention, the base material layer may be composed of a resin binder made of a hard resin material which is the same as or similar to (similar to) the hard resin material used in the case body. It is particularly preferable for further improving the transparency of the case as a whole. That is, in the present invention,
“Haze value” used as a measure of transparency is a value obtained by dividing scattered light transmittance by total light transmittance, and when two kinds of transparent materials are laminated, the light transmittance of each material is Even if it is high, if the refractive index of light is different, birefringence is caused at the interface between both materials, and if the interface is not smooth, diffuse reflection occurs, the transmitted light rays are scattered, and the haze value tends to increase. .
On the other hand, in the second aspect of the invention, by using the same or the same series of materials, the difference in the refractive index between the resin material forming the case body and the conductive layer can be eliminated or reduced, thereby improving the entire case. Has further improved the transparency.

In the second invention, the lower limit of the content of the conductive fine particles (60 parts) is further lowered (for example, the content of the conductive fine particles is 55 parts), and the content of the resin binder is accordingly increased. Even if the number is increased, the transparency of the entire case is sufficiently secured. However, in this case, it is necessary to use particularly conductive fine particles to ensure conductivity. Further, even if the thickness of the conductive layer formed by the coating liquid prepared according to the conditions of the second invention is slightly larger than that of the first invention (for example, about 1 μm), good transparency is secured. be able to.

Further, as shown in the fifth aspect of the invention, at least 1 is provided in the end opening or the side wall opening of the case body.
You may equip the above-mentioned fall prevention means. This drop-off prevention means is mainly for preventing the IC from dropping off from the case during transportation, and even if it is a lid (or a plug) attached to the end opening of the case body, It may be a stopper or the like attached to a groove-shaped opening provided in the longitudinal direction of the case body. It should be noted that it is desirable that the detachment preventing means be made of a conductive material, as with the conductive layer.

[0020]

In the case of the first invention, the case body having desired transparency and heat resistance by controlling the light transmittance, haze value and deflection temperature under load, and conductive fine particles dispersed in the base material layer. By controlling the volume specific resistance value, the primary particle size and the content thereof, it has desired conductivity and adhesion,
And a conductive layer that does not impair the transparency of the case body. Therefore, in the case of the present invention, the quality of the IC can be sufficiently controlled from the outside of the case, and the case has heat resistance sufficient to withstand a baking process at high temperature for a long time.
Further, the conductive layer adheres sufficiently to the case body to maintain conductivity. Therefore, according to the case of the present invention, both the producer and the user of the IC can save extra labor such as refilling of the IC accompanying the baking process, and the case is complicated process. Suitable for mass production because it can be manufactured without going through

In the case of the second aspect of the present invention, as the "resin binder" forming the base material layer, a hard resin material which is the same as or the same type (same series) as the hard resin material used for the case body is used. As a result, the case body and the conductive layer have approximately the same or similar refractive indices, and effectively suppress birefringence that tends to occur at the interface between the two and the scattering of transmitted light, so that the overall transparency of the case is It is further improved compared to the case of the first invention. Further, in the second aspect of the invention, since the transparency is particularly excellent, the transparency is not impaired even if the thickness of the conductive layer is slightly increased, and therefore the production is easy and the thickness of the formed conductive layer is reduced. Even if there is variation, the effect on the transparency of the entire case is small.

[0022]

EXAMPLES The present invention will be described below with reference to examples. A. Examples 1 to 4 and Comparative Example 1 (1) Outline and Fabrication of Case Example 1 A case A of this example has a substantially tubular shape (outer dimensions; 25 mm × 350 mm × 10 mm, thickness;
1 mm) of a case body 1 and a conductive layer 2 that covers the inner surface and the outer surface of the case body 1. The case body 1
1, as shown in FIG. 1, a slit (width: 5 mm) 11 along the longitudinal direction on the front side and a reverse groove portion (width: 15 mm, length: 350 mm, depth: 5 mm) along the longitudinal direction on the back side.
Have twelve. The case body 1 is made of a polysulfone resin (trade name; "Udel P-1700", manufactured by Amoco Co., Ltd.) using a single-screw extruder (trade name: "FS-50",
It is manufactured under the conditions of a barrel temperature of 330 ° C. and a screw rotation speed of 19 rpm.
The warpage of the case body 1 was measured on a surface plate along the longitudinal direction of the case body 1 using a gap gauge (the “warpage” in the following Examples, Comparative Examples and Test Examples was also measured by the same method. ) And 0.5 mm or less. The deflection temperature under load of the case body 1 is 173 ° C (18.6 kg).
f / cm ² ). Further, a test piece made of a long plate having a thickness of 1 mm and the same length as the above was prepared, and the light transmittance and the haze value were measured. The light transmittance was 86% and the haze value was 5%. there were.

On the other hand, the conductive layer 2 is formed by using the following antistatic coating material. That is, 65 parts of "Pastran 4110" (trade name, manufactured by Mitsui Mining & Smelting Co., Ltd.) as conductive fine particles, and a thermoplastic acrylic resin (trade name; "Dynar BR-113") as a resin binder,
(Mitsubishi Rayon Co., Ltd.) 35 parts, and then 300 parts of a solvent in which methyl ethyl ketone and toluene are mixed at a ratio of 1: 1 (weight ratio), and then "Pingment Zucker".
(Commercial name, manufactured by Red Devil Co., Ltd.), forcibly dispersed for 2 hours to dissociate the aggregated secondary particles into the original primary particles,
The antistatic paint to be used was prepared. In this case,
In order to improve dispersibility, a predetermined amount of silicon-based surfactant or the like may be added. Further, the conductive fine particles used here have a volume resistivity of 15 Ωcm in a solidified product and a primary particle diameter based on the Microtrac method (measured similarly in the following examples, comparative examples and test examples). The barium sulfate core material has a tin oxide film thickness of 8 μm and is doped with antimony oxide. Further, the acrylic resin was a methylmethacrylate-based modified resin and had a glass transition temperature of 77 ° C. The paint did not show layer separation or precipitation even after standing for more than one day.

Then, the case body 1 is held for 30 seconds.
It was immersed in ethyl acetate for degreasing and then dried.
Next, while making the longitudinal direction of the case body 1 vertical,
After being immersed in the antistatic paint for 30 seconds, 30c
After pulling up from the paint at a speed of m / min to form a coating film on the inner and outer surfaces of the case body 1, at room temperature of 25 ° C., 2
A conductive layer 2 was formed by drying for a period of time to prepare a case A according to this example. The surface electric resistance of Case A is
It was 150 MΩ (1.5 × 10 ⁸ Ω) and the film thickness measured by an ultrasonic film thickness meter was 1.8 μm. The conductive layer formed on the surface of the test piece under the same conditions as above had a light transmittance of 78% and a haze value of 21%.

Example 2 A case main body 1 of this example uses a polyether sulfone resin (trade name; "Radel A-300, manufactured by Amoco Co."), a barrel temperature of 350 ° C., and a screw rotation speed of 17 rp.
It was produced by the same method as in Example 1 except that m was used. The warp of the case main body 1 is 0.
It was 7 mm. Further, a test piece having a thickness of 1 mm was prepared and measured in the same manner as in Example 1. The light transmittance was 82%, the haze value was 6%, and the deflection temperature under load was 203 ° C. (18.6).
kgf / cm ² ). On the other hand, the conductive layer 2 was formed by the same method as in Example 1 except that the pulling rate from the antistatic coating was 50 cm / min.
The conductive layer 2 had a thickness of 1.6 μm and a surface electric resistance of 200 MΩ (2.0 × 10 ⁸ Ω). Also,
The test piece having a conductive layer formed on the surface had a light transmittance of 79% and a haze value of 18%.

Example 3 The case body 1 of this example uses a polyphenyl sulfone resin (trade name; "Radell R-5000, manufactured by Amoco Co."), a barrel temperature of 340 ° C., and a screw rotation speed of 15 rp.
It was produced by the same method as in Example 1 except that m was used. The warp of the case main body 1 is 0.
It was 4 mm. Further, a test piece having a thickness of 1 mm was prepared and measured in the same manner as in Example 1. The light transmittance was 78%, the haze value was 7%, and the deflection temperature under load was 190 ° C (18.6).
kgf / cm ² ). On the other hand, the conductive layer 2 was formed in the same manner as in Example 2 except that the pulling rate from the antistatic coating was 70 cm / min. The conductive layer 2 has a thickness of 1.0 μm and a surface electric resistance of 5
It was 00 MΩ (5.0 × 10 ⁸ Ω). In addition, the light transmittance of the test piece having a conductive layer formed on the surface is 76
%, And the haze value was 15.

Example 4 The case body 1 of this example uses polyarylate resin (trade name; “P-1001, manufactured by Unitika Ltd.”) except that the barrel temperature is 350 ° C. and the screw rotation speed is 12 rpm. The case body 1 was manufactured by the same method as in Example 1. The warp of the case body 1 was 0.5 mm, and a test piece having a thickness of 1 mm was prepared and measured as in Example 1. As a result, the light transmittance was 87%, the haze value was 2%, and the deflection temperature under load was 175 ° C (18.6 kgf / cm
² ) was. On the other hand, the conductive layer 2 was formed in the same manner as in Example 1 except that the pulling rate from the antistatic coating was 30 cm / min. In addition, this conductive layer 2
Has a thickness of 2.0 μm and a surface electrical resistance of 500 MΩ.
(5.0 × 10 ⁸ Ω). The test piece having a conductive layer formed on its surface had a light transmittance of 76% and a haze value of 18%.

Comparative Example 1 In the case of this comparative example, a conductive resin was not formed, and a polycarbonate resin (trade name; "Panlite AM-10" was used.
0 ", manufactured by Teijin Chemicals Ltd., and the barrel temperature is 180 ° C.,
The screw rotation speed was 15 rpm, and the screw was produced in the same shape as the case body. The warpage in this case is 0.
It is 2 mm or less. In addition, as in Example 1, the thickness is 1 m.
When a test piece of m was prepared and measured, the light transmittance was 88.
%, The haze value is 1%, and the deflection temperature under load is 138 ° C. (1
It was 8.6 kgf / cm ² .

(2) Performance test and its evaluation Visual observation and simulated transportation test As shown in FIG.
IP type integrated circuit (IC, chip size; 16mm x 4
After inserting 5 pieces of 0 mm × 3 mm) 3, both ends of the case A were sealed with rubber stoppers made of EPDM having a surface electric resistance of 10 ⁸ Ω. Then, an attempt was made to identify the characters printed on the surface of the integrated circuit 3 stored from outside the case A. At this stage, identification was possible in any case A. Furthermore,
Nine cases A each of which is in this state (in which the integrated circuit 3 is housed) are produced, bound with rubber bands, and then the upper and lower ends of the case A are reversed at a rate of 6 times / minute, and this operation is continued for 1 hour. Then, the shipping and transportation conditions of the integrated circuit 3 were simulated.

Next, the integrated circuit 3 was taken out from each case A, and the state of the surface of the lead frame 31 was examined with a stereoscopic microscope (magnification: 20 times). According to this, in each case A of Examples 1 to 4, no adhesion of coating film powder to the surface of the lead frame 31 due to damage to the conductive layer 2 was observed. Further, neither the case body 1 was damaged nor the conductive layer 2 inside the case body 1 was damaged. Further, even when the case body 1 is incised and the part where the integrated circuit 3 slides is observed by a stereoscopic microscope (magnification: 20 times), the conductive layer 2 in the case body 1 is not damaged or peeled. Not confirmed.

Baking Tests 9 pieces of the same integrated circuits 3 as described above were stored in the case A of each of Examples 1 to 4 and Comparative Example 1 (normal number of storages), 9 pieces each were prepared, and 1 cm was prepared. After arranging at intervals, under the conditions shown in Table 1, the sample was left in an oven and then cooled.

[0032]

[Table 1]

Then, the presence or absence of abnormality in the case body 1 and the conductive layer 2 was observed. The results are also shown in Table 1.
In addition, in the table, "○" means "no abnormality" and "x" means
Indicates "abnormality". According to this, in Case A of Comparative Example 1, twisting occurred and it was not in a state where it could be reused very much. On the other hand, in case A of Examples 1 to 4,
No abnormality such as breakage was found in the case body 1 and the conductive layer 2, and the integrated circuit 3 was not fixed to the inner surface of the case body 1. Further, the contact portion on the inner surface of the case body 1 of the integrated circuit 3 was also observed by a stereoscopic microscope in the same manner as above, but no abnormality such as scratches or peeling was confirmed.

Further, in the case A of Examples 1 to 4, the warp of the case body 1, the surface resistance of the conductive layer 2, and the characters on the surface of the integrated circuit 3 housed therein were identified. Further, a test piece made of a long plate having a thickness of 1 mm was prepared, and the conductive layer 2 was formed under the same conditions as the case main body 1 described above. went. These results are also shown in Table 1. According to this, Examples 1-4
In case A, the warpage and the surface resistance were not much different from the values before the baking process. Further, although the light transmittance and the haze value of the conductive layer 2 were slightly lowered as compared with those before the baking, there was no problem in identifying the characters on the surface of the integrated circuit 3, the lead frame, etc., and they could be sufficiently reused. .

B. Examples 5 to 8 and Comparative Examples 2 to 5 Using the same polysulfone resin as in Example 1, a case body was prepared under the conditions and methods shown in Table 2, and various antistatic paints were blended according to the formulation shown in the same table. and, a conductive layer on the inner surface and the outer surface of the case body in the same manner as in example 1 to prepare the case of examples 5-8 and Comparative examples 2-5. However, in Example 8 and Comparative Example 5, after forming the conductive layer,
It was baked and cured with hot air at a temperature of 150 ° C. for 20 minutes.

[0036]

[Table 2]

As the "resin binder" in Table 2, Example 5 was a thermoplastic modified acrylic resin (trade name "Dianal BR-90", manufactured by Mitsubishi Rayon Co., Ltd., solid content 100).
%)), And Example 6 and Comparative Examples 2 and 3 are thermoplastic type modified methacrylic resins (trade name "Dianal BR-11").
3 ”, manufactured by Mitsubishi Rayon Co., Ltd., solid content 100%), and Example 7 is a thermoplastic methacrylic resin (trade name“ DIANAL ”).
BR-87 ", manufactured by Mitsubishi Rayon Co., Ltd., solid content 100%)
Example 8 is a thermosetting methacrylic resin (trade name "Dianal HW-138", Mitsubishi Rayon Co., 50%
Comparative Example 4 is a thermoplastic acrylic resin (trade name “Dianal BR-10”) diluted with isopropyl alcohol.
7 ”, manufactured by Mitsubishi Rayon Co., Ltd., solid content 100%), and Comparative Example 5 is a thermosetting acrylic resin (trade name“ DIANAL S ”).
E-5102 ", manufactured by Mitsubishi Rayon Co., Ltd., diluted with 50% toluene). In addition, "conductive fine particles" in the table
In Example 5, only Example 5 was a tin oxide core material doped with antimony oxide (trade name "T-1", manufactured by Mitsubishi Metals Co., Ltd.), and others (Examples 6 to 8 and Comparative Examples 2 to 2).
5) is a barium sulfate core material coated with a tin oxide film and then doped with antimony oxide (Examples 6 and 8 and Comparative Examples 2 to 5; trade name "Pastran 4110", manufactured by Mitsui Mining & Smelting Co., Ltd., Example 7; trade name "Pastlan 4111", manufactured by Mitsui Mining & Smelting Co., Ltd.). Further, as "diluent" in the table, methyl ethyl ketone was used in Example 5, toerne was used in Example 6, Comparative Examples 2, 3 and 5, ethyl acetate was used in Example 7 and Comparative Example 5, and ethyl acetate was used in Example 8. Isopropyl alcohol was used respectively. For each of the above cases, each item listed in Table 3 was evaluated, and the results are shown in Table 3.

[0038]

[Table 3]

The evaluation method was the same as that shown in Example 1, and the "light transmittance" and "cloudiness" were the same as the conditions for forming a 1 mm-thick test piece on the case body. Under the condition, the conductive layer was formed. In addition, "characteristics after baking" in the table means various characteristics after baking each case at a temperature of 150 ° C for 10 hours. Further, in the table, "◎" means "especially good", "○" means "good", "△" means "somewhat good", "x" means "problem (inferior)", "XX" indicates "especially problematic (remarkably inferior)".

According to the above performance test, in Comparative Example 2,
The surface resistance of the conductive layer is too large (10 ¹⁰ Ω or more) and cannot be used. Further, in Comparative Example 3, the light transmittance and the haze value are poor, and the transparency is insufficient, so that it cannot be said to be practical. Furthermore, in Comparative Example 4, the integrated circuit adheres to the conductive layer after the baking step (the separation property and the film separation property are poor), and the coating film forming the conductive layer tends to peel (the coating film state is poor). It is in. Further, in Comparative Example 5, the coating film was cured by heat treatment, and the thick coating film added to increase the cohesive force of the coating film, resulting in poor adhesion to the case body. Peeling occurred. On the other hand, in Example 5, the surface electric resistance of the conductive layer was slightly high, and in Example 7, the haze value was a little high because the blending ratio of the conductive fine particles was high. In addition, Example 6 satisfies all required performances and can be said to be an excellent case. Further, in Example 8, although the coating film was cured by heat treatment, the coating film was thin, so that the adhesion to the case body was good, and peeling of the coating film did not occur even when the case was bent greatly.

The content of the conductive fine particles is preferably about 62 to 73 parts based on 100 parts of the entire conductive layer, and the transparency of each test piece after baking has a light transmittance of 75%.
It is preferable for use that the haze value is not less than 25%. Further, comparing Example 7 and Comparative Example 2, when the content of the conductive fine particles is less than 60 %, the antistatic performance is poor and the glass transition temperature is 50 ° C. as compared with Comparative Example 4.
It was found that satisfactory results could not be obtained when the base material layer was formed with the resin binder described in 1.

C. Test Examples 1 to 12 (1) Outline and Preparation of Case Test Example 1 The case main body 1 of this test example is a polyether sulfone resin (trade name; "Radel A-200, manufactured by Amoco Co., Ltd.") instead of the above polysulfone resin. Was produced by the same method as in Example 1 except that
The conductive layer 2 is produced using the following antistatic coating material. That is, "pastran 41 as a conductive fine particle
11 "(trade name, manufactured by Mitsui Mining & Smelting Co., Ltd.) was added with 35 parts of the same polyethersulfone resin as that used in the production of the container body 1 as a resin binder, followed by addition of 350 parts of dichloromethane, followed by execution. Forcible dispersion was carried out for 3 hours using the same “Pingment Zuker” as in Example 1 to dissociate the aggregated secondary particles into the original primary particles for adjustment.
The conductive fine particles used here were the same as those in Example 1 except that the solidified product had a volume resistivity value of 12 Ωcm and a primary particle diameter of 0.1 μm or less. Also, this coating material, as in the case of Example 1, did not show layer separation or precipitation even after standing for one day or more.

Then, the case body 1 is held for 30 seconds.
It was immersed in toluene for degreasing and then dried. Next, the case body 1 is dipped in the antistatic coating material with the longitudinal direction being vertical, and then pulled up from the coating material while adjusting the pulling speed so that the film thickness becomes a predetermined thickness. After forming a coating film on the inner and outer surfaces of
A conductive layer 2 was formed by drying with hot air at 40 ° C. for 1 hour to prepare a case A according to this test example.

Test Examples 2 to 6 Case A of Test Examples 2 to 6 and Case A of Test Example 1 are as follows. That is, in Test Examples 2, 5 and 6, the polysulfone resin (trade name; "Udel P-17"
00 "manufactured by Amoco Co., Ltd. in Test Example 3 was used as a polyphenyl sulfone resin (trade name;" Radel R-500 ").
0 ", manufactured by Amoco Co., Ltd., and polyarylate resin (trade name;" P-1001 ", manufactured by Unitika Co., Ltd.) in Test Example 4 were used to manufacture the case body 1. In addition, the resin binder in each antistatic coating is used for the case body 1
Each of the binders made of the same resin material as that of the resin was used. Further, the conductive fine particles in the coating composition were obtained by doping the surface of a tin oxide core material with antimony oxide only in Test Example 2 (trade name "T-1", manufactured by Mitsubishi Metals Co., Ltd.).
Other than that is the same as in Test Example 1.

Test Examples 7 to 12 Case A of Test Examples 7 to 12 and Case A of Test Example 1 are as follows. That is, except that the same polyether sulfone resin as in Test Example 1 was used in Test Example 12,
A case body 1 was produced using the same polysulfone resin as in Test Example 2 and the like. In addition, as a resin binder in each antistatic coating, in Test Example 7, a thermoplastic methacrylic resin (trade name; "Dianal BR-87", manufactured by Mitsubishi Rayon Co., Ltd., solid content 100%) was used. Is a thermoplastic modified acrylic resin (trade name; "Dianal BR-90",
Mitsubishi Rayon Co., Ltd., solid content 100%), Test Examples 9, 1
0 and 12 are polysulfone resin (trade name; "Udel
P-1700 ", manufactured by Amoco Co., Ltd., solid content 100%). Further, Test Example 11 is a polysulfone resin (trade name; "Udel P-1700", manufactured by Amoco,
Solid content 100%) and thermoplastic methacrylic resin (trade name;
A binder made of a resin material in which "Dianal BR-87", manufactured by Mitsubishi Rayon Co., Ltd., solid content 100%) was mixed at a ratio of 2: 1 was used. In addition, the conductive fine particles in the paint were obtained by doping the surface of the tin oxide core material with antimony oxide only in Test Example 10 (trade name "SN-100",
Ishihara Sangyo Kaisha, Ltd.) was used, and the same as in Test Example 1 was used.

The material of the case body, the deflection temperature under load (° C.), and the light transmittance (%, m) of Test Examples 1 to 12 described above.
m), haze value (%, mm) and the like as "case body characteristics", and the resin binder material, blending amount, conductive fine particle diameter, conductive fine particle blending amount and the like as "paint characteristics" in Tables 4 and 5. Shown in. The characteristic values such as light transmittance, haze value and deflection temperature under load in the table are all measured by the same method as in Example 1. In addition, the warpage of the case bodies 1 of the respective test examples before the formation of the conductive layer 2 was 0.7 mm or less, and at this stage, no abnormal appearance was observed in any of the case bodies 1.

[0047]

[Table 4]

[0048]

[Table 5]

As the diluent in each table, "dichloromethane" was used as described above in Test Example 1, and Test Example 3 was used.
In the above, except that "N, N-dimethylacetamide" was used, "chlorobenzene" was used. In addition, "P
“ES” is the above “polyether sulfone resin” and “PS
“F” represents the above “polysulfone resin”, “PPS” represents the above “polyphenylsulfone resin”, and “PAR” represents the above “polyarylate resin”. Further, "thermoplastic type" means the above "thermoplastic methacrylic resin", and "thermoplastic type modified" means the above "thermoplastic type modified acrylic resin". Furthermore, the "mixed product" refers to a mixed product of the thermoplastic methacrylic resin and the polysulfone resin. For each of the above cases A, the items listed in Tables 6 and 7 were evaluated, and the results are shown in the same table.

[0050]

[Table 6]

[0051]

[Table 7]

The warpage of each case A after baking was 1 mm or less. In addition, the evaluation methods in the table are the same as those shown in Example 1, and the "light transmittance" and "cloudiness value" are as follows:
The conductive layer was formed under the same conditions as the case body. The "characteristics after baking" in the table means various characteristics after baking each case for 10 hours at a temperature of 155 ± 1 ° C. Furthermore, the meanings of “⊚”, “∘” and the like in the table are the same as in Table 3.

According to the above performance tests, as shown in Test Examples 1 to 6 and 9, it is found that the haze value is greatly improved when the container body 1 and the resin binder are made of the same resin. Particularly, in Test Example 5, good results are shown despite the large thickness of the conductive layer 2. When the container body 1 and the resin binder are made of the same series of resin as in Test Example 12, a mixed product of the resin forming the container body 1 and another resin having transparency as in Test Example 11 is used as a resin. Even when used as a binder, the haze value was improved as compared with Test Examples 7 and 8 in which both were composed of different kinds and different series of resins. In the case of Test Example 10,
Although the container body 1 and the resin binder were made of the same resin, the haze value was not improved because the primary particle diameter of the conductive fine particles and the thickness of the conductive layer were excessive. In addition, there was almost no problem in the basic performance such as the adhesion of the coating film and the adhesion to the IC throughout all the test examples described above, but when the compounding amount of the conductive fine particles was small as in Test example 9. Had poor conductivity.

The present invention is not limited to the specific examples described above, and various modifications may be made within the scope of the present invention depending on the purpose and application. That is,
In this embodiment, the case (tube shape, etc.) whose main purpose is to store the DIP type IC has been described.
It can also be applied to a case (such as a dish) whose main purpose is to store C.

[0055]

Since the case of the present invention sufficiently satisfies all the required performances of conductivity, transparency and heat resistance, it is not only used for transportation from the producer of IC to the user, but In each step of mounting and the like, quality control can be performed with the IC stored in the case, and it is not necessary to take out the IC from the case, and baking can be performed without impairing the quality. Therefore, both IC producers and users can improve work efficiency. Moreover, since no complicated process is required for manufacturing the case, it is suitable for mass production. When the case body and the resin binder of the base material layer are made of the same or the same kind of hard resin material, the transparency of the entire case can be further improved.

[Brief description of drawings]

FIG. 1 is a partial perspective view of an integrated circuit case body according to a first exemplary embodiment.

FIG. 2 shows an integrated circuit (I
It is explanatory drawing which shows the state which accommodated C).

FIG. 3 is a partial vertical cross-sectional view showing a state of a conductive layer.

[Explanation of reference numerals] 1; container body, 2; conductive layer, 21; conductive fine particles, 22;
Base material layer.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01B 1/22 Z 7244-5G H01L 23/00

Claims (5)

[Claims] 1. Thickness 1 according to JIS K7105 test method
Light transmittance of 75% or more per mm and thickness of 1 m
Haze value per m is 8% or less, and further JISK7
202A test body made of a hard resin material having a deflection temperature under load of 150 ° C. or higher and containing a large number of integrated circuits. The case body has a substantially tubular or plate shape, and a conductive material that covers the inner and outer surfaces of the case body. A base material layer made of a resin binder, and conductive fine particles dispersed in the base material layer and having a volume resistivity of 10 ² Ωcm or less and a primary particle diameter of 0.2 μm or less. , And the content of the conductive fine particles is 60 to 75 parts by weight when the total of the resin binder and the conductive fine particles is 100 parts by weight, and the conductive fine particles are exposed on the surface of the conductive layer. A case for an integrated circuit characterized in that 2. The case for an integrated circuit according to claim 1, wherein the base material layer is made of a resin binder made of a hard resin material that is the same as or similar to the hard resin material that forms the case body. 3. The hard resin material is polysulfone resin, polyether sulfone resin, polyphenyl sulfone resin or polyarylate resin.
The integrated circuit case described. 4. The conductive fine particles are composed of a substrate composed of barium sulfate particles, and a tin oxide coating film formed on the surface of the substrate by doping the surface with indium oxide or antimony oxide. The integrated circuit case according to claim 1. 5. The integrated circuit case according to claim 1, wherein at least one drop-out preventing means is attached to the end opening or the side wall opening of the integrated circuit case body.