JP2007190905A - Mixing device, mixture and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mixing device capable of eliminating the occurrence of and the contamination by foreign substances attributable to the structure of the mixing device, a mixture in which the content of foreign substances with extremely fine sizes are reduced and a highly reliable semiconductor device using the mixture. <P>SOLUTION: The mixing device comprises at least a mixing tank to receive and mix materials to be mixed, an agitating blade shaft with agitating blades at the one end, a shaft-fixing part with a bearing to which the other end of the agitating blade shaft is fitted and fixed, a self-rotating shaft to rotate the shaft-fixing part and a driving means to drive the self-rotating shaft and provided with a non-contact means to avoid the contact of the metal parts with each other. The mixture is obtained by using the mixing device. The semiconductor device is obtained by using the mixture. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a mixing device, a mixture, and a semiconductor device, and more specifically, a mixing device capable of suppressing the generation of metal foreign matter in the mixture, a mixture using the device, and a semiconductor using the mixture. Relates to the device.

  In recent years, as electronic devices such as communication mobile devices, flat-screen TVs, word processors, personal computers, IC cards, and electronic notebooks become smaller and thinner, there is an increasing demand for smaller and thinner IC packages. In order to satisfy this requirement, resin in the bare chip mounting field such as TCP (Tape Carrier Package), COB (Chip On Board), COF (Chip On Film), COG (Chip On Glass), MCM (Multi Chip Module), etc. An IC chip is sealed using a sealing material, and TCP using a resin sealing material is mainly used in a driving IC for an LCD panel.

  The resin sealing material is generally manufactured by mixing an epoxy resin, a curing agent, an inorganic filler, and other additives, and can seal an IC chip in a liquid state. It has a feature that a flexible sealing method for a small and ultra-thin package can be provided. In recent years, the spacing (pitch) between the wires or bumps connecting the IC chip circuit and the base circuit is 40 μm due to the miniaturization of the IC chip circuit, such as NUF (Non Flow Under Fill) and CUF (Capillary Under Fill). With the progress of narrowing the pitch to 20 μm or 15 μm, a material having a particle size equal to or smaller than the pitch interval is used as the inorganic filler.

In addition, a mixing apparatus for producing a mixture such as a resin sealing material is usually a mixing (kneading) that can uniformly mix and disperse various materials such as a raking machine, a three-roll, a ball mill, a planetary mixer, and a homomixer. ) Devices are used (see Non-Patent Documents 1, 2, 3, etc.). In particular, a mixing device of a type called a raking machine or a planetary mixer has a mixing blade (shaft with stirring blades) for stirring. It is often used because it can perform planetary motion and mix the mixture efficiently. Such a mixing apparatus is generally composed of a mixing tank for charging and mixing raw materials, a removable stirring blade, a driving unit for the stirring blade, and a casing portion for rotating and moving these components vertically. In addition, a vacuum-type defoaming mechanism for removing minute bubbles contained in the resin sealing material, and a magnetic metal that can be generated from the metal material constituting the apparatus in the mixing process A metal sorting and collecting device for selectively collecting and removing foreign substances (see, for example, Patent Document 1) and a mechanism for moving the mixing tank up and down manually or electrically to facilitate the introduction of raw materials may be provided. In addition, when the said vacuum type defoaming processing mechanism is connected, a stirring blade and its drive part are attached to the mixing tank upper part, and are accommodated in the container which comprises a closed system. Moreover, raising / lowering of a mixing tank is attained by combinations, such as a rack and pinion.
JP 2000-136289 A “Aiko Chemical Mixer Catalog”, Aikosha Mfg. Co., Ltd. "Crusher catalog", Ishikawa factory “Planetary Mixer Catalog”, Special Machine Industries Co., Ltd.

  In resin encapsulants, it is well known that the inclusion of conductive foreign matter such as metal foreign matter is a major cause of device failure typified by electrical insulation failure (short) in the circuit interval. In order to cope with the narrow pitch, it is required to remove conductive foreign matters or metal foreign matters having a smaller size (average particle diameter) than conventional ones from the resin sealing material or to suppress the mixing thereof.

  Examples of the means for removing the conductive foreign matter include a means for filtering the raw material to be mixed using a mesh in advance or removing a metal foreign matter that is magnetically attached using a magnet. As a means for suppressing the mixing of conductive foreign matters in the manufacturing (mixing) step of the resin sealing material, it is made of an inorganic material such as alumina or zirconia having excellent wear resistance as a mixing tank or a stirring blade. Means for reducing the occurrence of conductive foreign matter itself using a material.

  However, only by applying these conventional means, a sealing material that can cope with the recent narrowing of the circuit interval, that is, a sealing material with a low content of conductive foreign matters having an average particle diameter of about 10 to 40 μm. Is difficult to obtain efficiently.

  Accordingly, the present inventors have investigated in detail the causes of the inclusion and increase of metal foreign substances in the resin sealing material manufacturing process, and as a result, the wear during the sliding of the mixing blade of the mixing blade of the mixing device, the stirring blade shaft Wear powder (metal foreign matter) is generated due to wear during sliding between the bearing and the bearing, gear wear during sliding between the gearbox drive shaft and casing, and wear during sliding of the metal when moving up and down the mixing tank. It was found that it was mixed in the material. In particular, when attaching and detaching the stirring blade shaft to feed the raw materials, the bearing and the bearing part are in direct contact with each other, and the tolerance when mounting and fixing is made large to facilitate the attachment and detachment of the stirring blade shaft. As a result, it was found that a large amount of extraneous metal foreign matter was generated by the contact between the stirring blade shaft and the bearing portion during operation of the mixing apparatus. In addition, metal seals that do not require periodic lubrication are used for the gearbox drive shaft and casing, but it was also found that metal foreign matter was generated from here.

  In view of the above, an object of the present invention is to provide a mixing apparatus capable of suppressing the generation of foreign substances due to the structure of the mixing apparatus and the mixing thereof.

  It is another object of the present invention to provide a mixture in which the content of extraneous foreign matters having a size of 10 μm or more, particularly about 10 to 40 μm is reduced, and a highly reliable semiconductor device using the mixture.

  That is, the present invention is characterized by the following items (1) to (13).

  (1) A mixing tank for charging and mixing the mixture, a stirring blade shaft having a stirring blade for stirring the mixture in the mixing tank at one end, and the other end of the stirring blade shaft are inserted. In a mixing apparatus comprising at least a shaft mounting component having a fitting portion that is fitted and fixed, a rotation rotating shaft for rotating the shaft mounting component, and a driving means for driving the rotation rotating shaft. A mixing apparatus, further comprising non-contact means for avoiding contact between parts.

  (2) The non-contact means is disposed so that the stirring blade shaft or a component for fixing the stirring blade shaft does not contact the bearing portion of the shaft mounting component (1) ) The mixing device described.

  (3) The mixing apparatus according to (1) or (2), wherein the non-contact means is a buffer material.

  (4) The mixing device according to (3) above, wherein the buffer material is a resin buffer material.

  (5) The mixing apparatus according to any one of (1) to (4), wherein the mixing tank is detachable.

  (6) The mixing apparatus according to any one of (1) to (5), wherein both the mixing tank and the stirring blade are made of an inorganic material.

  (7) The mixing apparatus according to any one of (1) to (6), further including a driving unit for revolving the rotating shaft.

  (8) The mixing apparatus according to any one of (1) to (7), further including a foreign matter collecting means.

  (9) The mixing apparatus according to (8), wherein the foreign matter collecting means is a collecting pocket or a permanent magnet.

  (10) A mixture obtained by mixing the mixture using the mixing device according to any one of (1) to (9).

  (11) The mixture according to (10), wherein the mixture includes an epoxy resin, a curing agent, and an inorganic filler.

  (12) The mixture as described in (10) or (11) above, which is a resin sealing material.

  (13) A semiconductor device comprising the mixture according to any one of (10) to (12).

  According to the mixing apparatus of the present invention, it is possible to provide a mixture in which the content of extraneous foreign matter having a size of 10 μm or more, particularly about 10 to 40 μm, is reduced. However, it becomes possible to provide a highly reliable semiconductor device using a resin sealing material and a resin sealing material that are significantly reduced compared to the prior art.

  The mixing apparatus of the present invention includes a mixing tank for charging and mixing a mixture, a stirring blade shaft having one end of a stirring blade for stirring the mixture in the mixing tank, and the other end of the stirring blade shaft. In a mixing apparatus comprising at least a shaft mounting component having a bearing portion in which is inserted and fixed, a rotation rotating shaft for rotating the shaft mounting component, and a driving means for driving the rotation rotating shaft. It is characterized by further comprising non-contact means for avoiding contact between parts. In addition, the mixing apparatus of this invention may be equipped with the other components with which a well-known mixing, kneading | mixing, and grinding | pulverization apparatus is provided as needed.

  Hereinafter, although the principal part of the mixing apparatus of this invention is demonstrated using drawing, this invention is not limited to the following description and embodiment.

  FIG. 1A is a schematic front view showing a state in which a mixing tank 2 into which a mixture 1 is charged is placed on a mixing tank lifting table lifter 3 in the mixing apparatus of the present invention. The mixture 1 is detachable in order to make it easy to charge or mix. Moreover, FIG.1 (b) is a schematic front view which shows the state which raised the said mixing tank 2 to the mixing position manually or electrically. Of course, the mixing apparatus of the present invention can apply a known mixing tank moving means other than the table lifter.

  FIG. 2 is a cross-sectional view showing a state where two stepped round bar-shaped stirring blade shafts 4 are fitted and fixed to the bearing portions of the shaft mounting component 9. The stirring blade shaft 4 and the shaft mounting component 9 are fixed by a screw thread 5 and a stirring blade shaft fixing nut 6 cut at the upper end of the stirring blade shaft 4, and between the bearing portion and the stirring blade shaft 4 and Between the bearing portion and the stirring blade shaft fixing nut 6, a resin cushioning material is disposed as a non-contact means so that they do not directly contact each other. The material of the buffer material used as the non-contact means is not particularly limited, but a resin material is preferable. Further, the shape of the cushioning material may be appropriately determined according to the device structure, and is not particularly limited. For example, the resin cushioning material 7 disposed between the fixing nut 6 and the bearing portion is ring-shaped, and the resin ring 10 is also provided with a countersunk bolt (not shown) at the lower portion of the bearing portion to which the stirring blade shaft 4 is attached. ). As described above, in the present invention, it is possible to suppress the amount of metal foreign matter generated due to vibration or the like during operation of the mixing device by disposing the non-contact means in a place where the metal part can contact. .

  In addition, the mixing apparatus of the present invention collects foreign matter generated by contact between parts where it is difficult to dispose the non-contact means as described above, and collects foreign matter to prevent the contamination. Means may be provided. In FIG. 2, as a foreign matter collecting means, a collection pocket 11 for collecting the metallic foreign matter 14 generated by sliding between the rotation shaft 12 and the rotation shaft 13 disposed inside thereof is attached to the shaft. It is formed as a counterbore part (concave part) in which the component 9 is deeply cut.

  FIG. 3 is a schematic cross-sectional view of a drive unit including drive means such as a gear for rotating the rotation shaft 13. More specifically, in FIG. 3, a weir plate 18 is attached to the upper end of the smooth top plate 17 on the planetary motion gear box 16 for rotating and revolving the rotation shaft, and the smooth top plate 17 and the planetary motion gear box are attached. 16 and a connecting bolt 19 for connecting the casing portion 24 to which a permanent magnet 20 as a foreign matter collecting means is attached, which is generated by driving friction between the first gear 21 and the second gear 22, The metal foreign material 23 spilling from the gap 25 between the fixed cover 15 and the casing portion 24 is blocked by the barrier plate 18 and collected by the permanent magnet 20.

  As described above, the mixing device of the present invention can effectively suppress the amount of foreign matter generated due to the device structure, in particular, conductive foreign matter such as metal foreign matter. Since it is also possible to prevent mixing into the mixture, in particular, materials for wiring boards or semiconductor devices in which mixing of conductive foreign substances is not desirable, for example, resins containing epoxy resins, curing agents and inorganic fillers, etc. It is suitable for producing an insulating resin composition for forming a sealing material or an insulating resin layer. Of course, it may be used to produce a conductive paste, and it is also possible to produce a mixture with less foreign matter contamination in the fields of paints, adhesives, cosmetics, foods and the like. In the present invention, conventionally known materials and conditions can be applied to the material type and mixing conditions of the mixture, and may be appropriately determined according to the use and characteristics of the mixture.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited to this.

(Mixture for evaluation)
As the mixture to be evaluated, a bisphenol A type liquid epoxy resin (trade name R140P, manufactured by Mitsui Chemicals, Inc.) was used after removing foreign matters through a 20 μm nylon filter and a 10 μm nylon filter. The number of foreign substances collected from each filter was 1 for 20 μm or more and 6 for 10 μm to less than 20 μm.

Example 1
In the clearance between the stirring blade shaft and the bearing part of the Ishikawa Factory's Leica machine (model 24P type), as shown by 8 in FIG. 2, a resin cushioning material (nylon material (manufactured by Nippon Polypenco, MC Nylon) processed into a stepped hollow sleeve shape having a thickness of about 2 to 3 mm (smaller outer diameter of about 22 mm, larger outer diameter of about 39 mm) was attached, and the mixing apparatus of Example 1 was obtained. In addition, the raiki machine made by Ishikawa Factory Co., Ltd. has one end of a mixing tank for charging and mixing the mixture, a lifter for raising and lowering the mixing tank, and a stirring blade for stirring the mixture in the mixing tank. A rotating shaft for rotating the shaft mounting component, a rotating shaft for rotating the rotating shaft, and a rotating shaft for rotating the rotating shaft. And a drive device for revolving, and has a structure similar to the structure shown in FIGS. 2 and 3. The bearing portion, the stirring blade shaft, and the nut for fixing the stirring shaft are made of metal. In addition, the rotation shaft of the rotation shaft is configured such that the rotation shaft disposed on the outer periphery of the rotation shaft slides with an oilless metal sleeve.

  Next, 1 kg of the evaluation epoxy resin is charged into the mixing tank of the mixing apparatus, and after mixing for 20 minutes at 20 rpm, the evaluation epoxy resin is recovered and the number of foreign matters mixed during mixing. Was measured. In the measurement method, the collected epoxy resin for evaluation was sequentially filtered through a 20 μm nylon filter and a 10 μm nylon filter, and foreign matters remaining on each filter were collected and counted. The results are shown in Table 1.

(Example 2)
As shown by 7 in FIG. 2, a resin ring (in the vicinity of the opening) between the fixed nut of the stirring blade shaft and the bearing portion (near the opening) of the rough machine (model 24P type) manufactured by Ishikawa Factory Co., Ltd. A nylon material (manufactured by Nippon Polypenco Co., Ltd., MC nylon) processed into a ring shape having a thickness of about 2 to 3 mm, an inner diameter of 16.5 mm, and an outer diameter of 32 mm was attached to obtain a mixing apparatus of Example 2.

  Next, 1 kg of the evaluation epoxy resin is charged into the mixing tank of the above mixing apparatus, and after mixing for 20 minutes at 20 rpm, the evaluation epoxy resin is recovered and the number of foreign matters mixed during mixing. Was measured in the same manner as in Example 1. The results are shown in Table 1.

(Example 3)
A resin cushioning material and a resin ring are attached to a rough machine (model 24P type) manufactured by Ishikawa Factory, as in Examples 1 and 2, and a weir plate and a permanent magnet are attached as shown in FIG. The mixing apparatus of Example 3 was obtained.

  Next, 1 kg of the evaluation epoxy resin is charged into the mixing tank of the above mixing apparatus, and after mixing for 20 minutes at 20 rpm, the evaluation epoxy resin is recovered and the number of foreign matters mixed during mixing. Was measured in the same manner as in Example 1. The results are shown in Table 1.

(Comparative Example 1)
1kg of epoxy resin for evaluation is put into the mixing tank of Irakawa Factory's Leica machine (model 24P type) and mixed for 20 minutes at 20 rpm, then the evaluation epoxy resin is recovered and mixed. The number of mixed foreign matters was measured in the same manner as in Example 1. The results are shown in Table 1.

  From Table 1, the evaluation resin mixed using the mixing apparatus of Examples 1 to 3 in which the non-contact means and the foreign matter collecting means are arranged uses the mixing apparatus of Comparative Example 1 in which these means are not arranged. It can be seen that the mixing of foreign substances is reduced as compared with the mixed evaluation resin.

It is a schematic front view of the removable mixing tank and the raising / lowering apparatus which raises / lowers this. It is a schematic sectional drawing which shows the state by which the stirring blade axis | shaft was inserted and fixed to the bearing part of shaft attachment components. It is a schematic sectional drawing of a drive part provided with drive means, such as a gear, for rotating a rotation axis.

Explanation of symbols

1: Material 2: Mixing tank 3: Table lifter 4: Stirring blade shaft 5: Thread 6: Stirring blade shaft fixing nut 7: Resin ring 8: Resin cushioning material 9: Shaft mounting component 10: Resin ring 11: Collection pocket 12: Rotating rotating shaft 13: Rotating rotating shaft 14: Metal foreign object 15: Main body fixing cover 16: Planetary movement gear box 17: Smooth top plate 18: Dam plate 19: Connection bolt 20: Permanent magnet 21: 1 No. gear 22: No. 2 gear 23: Metal foreign object 24: Planetary movement gear box upper casing part 25: Clearance

Claims (13)

  A mixing tank for charging and mixing the mixture, a stirring blade shaft having a stirring blade for stirring the mixture in the mixing tank at one end, and the other end of the stirring blade shaft are inserted and fixed. In a mixing apparatus comprising at least a shaft mounting component having a bearing portion, a rotation rotating shaft for rotating the shaft mounting component, and a driving means for driving the rotation rotating shaft, A mixing device further comprising non-contact means for avoiding contact.   2. The mixing according to claim 1, wherein the non-contact means is arranged so that the stirring blade shaft or a component for fixing the stirring blade shaft does not contact a bearing portion of the shaft mounting component. apparatus.   The mixing apparatus according to claim 1 or 2, wherein the non-contact means is a buffer material.   The mixing apparatus according to claim 3, wherein the buffer material is a resin buffer material.   The mixing apparatus according to claim 1, wherein the mixing tank is detachable.   6. The mixing apparatus according to claim 1, wherein both the mixing tank and the stirring blade are made of an inorganic material.   The mixing apparatus according to any one of claims 1 to 6, further comprising a driving means for revolving the rotating shaft.   The mixing apparatus according to claim 1, further comprising a foreign matter collecting means.   The mixing apparatus according to claim 8, wherein the foreign matter collecting means is a collecting pocket or a permanent magnet.   A mixture obtained by mixing a mixture using the mixing apparatus according to any one of claims 1 to 9.   The mixture according to claim 10, wherein the mixture includes an epoxy resin, a curing agent, and an inorganic filler.   It is a resin sealing material, The mixture of Claim 10 or 11 characterized by the above-mentioned.   A semiconductor device comprising the mixture according to claim 10.

Images