JP4719246B2 - Crimp unit structure - Google Patents

Description

  The present invention relates to a pressure-bonding unit structure used for joining a glass substrate electrode terminal and a flexible substrate electrode terminal, and joining a glass epoxy substrate electrode terminal and a flexible substrate electrode terminal.

As described in the following patent documents, metal materials such as stainless steel, cemented carbides, and alumina-based ceramic materials are known as crimping tool materials constituting the crimping unit used for joining the electrode terminals. ing.
JP 7-235563 A JP-A-11-145165 JP 2002-261121 A

  In recent years, the formation pitch of the electrode terminals to be joined tends to be reduced, and high-precision and high-reliability joining is required at a lower cost. For this purpose, it is necessary to accurately maintain the parallel flatness of the crimping surface of the crimping unit that sandwiches the material to be crimped from both sides.

  However, it is difficult for the above-mentioned conventional crimping tool materials to accurately maintain the parallel flatness of the crimping surfaces of the two tools due to the relationship between the thermal expansion coefficient and the thermal conductivity coefficient, and the temperature in the tool at the time of joining. There is a tendency that the variation of the adhesive material is uneven, the variation in the curability of the adhesive material, and the deformation such as the elongation of the flexible substrate become non-uniform. For this reason, there is a high possibility that bonding failure between the electrode terminals occurs, and the low cost, high accuracy, and high reliability may not be sufficiently satisfied.

  The problem to be solved by the present invention is that the parallel flatness of the crimping surface can be accurately maintained, there is no occurrence of poor bonding, low cost, high accuracy, and high reliability can be sufficiently satisfied. An object of the present invention is to provide a pressure bonding unit structure that can be suitably applied to a material to be bonded which is a glass substrate, an adhesive, and an FPC substrate.

The crimping unit structure of the present invention includes two crimping tools arranged vertically with a material to be crimped interposed therebetween, and upper and lower holding parts that hold the crimping surfaces of the two crimping tools in parallel, and only the upper holding part. In addition, an even number of cartridge-type heaters are arranged evenly on the left and right with respect to the center of the holding portion, and the effective length of the cartridge-type heater is the depth length of the cartridge-type heater inserted into the holding portion. in the range of ± 20% of the crimping tool, _Si 3 _{N 4} and consists _Si 3 _{N 4} group ceramic material containing more than 50 vol%, the _Si 3 _{N 4} group ceramic material, _alpha-Si 3 N ₄ phase and β-Si ₃ N ₄ phase crystals, and the proportion of α-Si ₃ N ₄ phase in the two phases is 12 % or more and 39.8 or less by volume%, and the α-Si ₃ N _4, some the _Si 3 _{N 4} is Y, g, has been replaced by O, or Al, the beta-Si3 N4 phase state, and are not part the _Si 3 _{N 4} is replaced by O or Al, and the _Si 3 _{N 4} group ceramic material In addition, the parallel flatness of the pressure-bonding surface can be accurately maintained by processing the pressure-bonding surface to have a parallelism of 5 μm or less and a flatness of 2 μm or less .

As the two crimping tool member disposed vertically across the sheath pressing member, the _Si 3 _{N 4} containing 50% by volume or more, of _α-Si 3 _{N 4} phase and _β-Si 3 _{N 4} phase 2 phase By using a Si ₃ N ₄ based ceramic material having a crystal and a ratio of α-Si ₃ N ₄ phase occupying 2 phases in a volume% of 5 or more and 50 or less, a material to be bonded in combination with the pressure bonding unit structure It is possible to more accurately maintain the parallel flatness of the pressure-bonding surface that sandwiches from both sides.

Si ₃ N ₄ has a coefficient of thermal expansion that is a fraction of that of conventional metal tools, cemented carbide, and alumina-based ceramic materials, so it has excellent plane accuracy from room temperature to high temperatures. Can be maintained, and can be used as a thermocompression bonding tool material that can be bonded with high accuracy, low cost, and high reliability. Then, the thermocompression bonding tool material, in order to ensure desired toughness, thermal expansion coefficient, it is essential that the Si ₃ N ₄ group ceramic material containing Si ₃ N ₄ 50% by volume or more.

Further, this Si ₃ N ₄ base ceramic material has two-phase crystals of α-Si ₃ N ₄ phase and β-Si ₃ N ₄ phase, and the proportion of α-Si ₃ N ₄ phase in the two phases is volume. % Needs to be 5 or more and 50 or less.

In the α-Si ₃ N ₄ phase, a part of Si ₃ N ₄ is substituted with Y, Mg, O, and Al, and in the β-Si ₃ N ₄ phase, a part of Si ₃ N ₄ is O. , Al. The _α-Si 3 _{N 4} phase and _β-Si 3 _{N 4} phase ceramic material having a two-phase crystals consists either alone phase of _α-Si 3 _{N 4} phase and _β-Si 3 _{N 4} phase Since the crystal structure is finer than the ceramic material, the bending strength is high, and the porosity is as low as 0.5% or less, a thermocompression bonding surface having excellent flatness and surface roughness can be obtained.

  Joining using the crimping unit structure using the crimping tool material of the present invention is capable of highly accurate joining, does not cause joining failure, and can sufficiently satisfy low cost and high reliability. is there.

  Hereinafter, embodiments of the present invention will be described by way of examples.

  FIG. 2 shows an example of the crimping unit structure 10 of the present invention. In the same figure, 1 and 2 show the unit base material of each of upper and lower sides, and 3 and 4 show the tool presser of each of the upper and lower sides. The upper and lower crimping tools 7, 8 are sandwiched between the unit bases 1, 2 by the tool holders 3, 4, and are fixed by screws 5, 6. Reference numeral 9 denotes a heater arranged only on the upper part of the unit base 1 on which the upper crimping tool 7 is held. The upper crimping tool 7 uses the crimping tool material according to the present invention, but the lower crimping tool 8 preferably uses the crimping tool material according to the present invention. The heater 9 is preferably a cartridge type heater, but is not particularly limited thereto. The effective length of the heater is preferably within a range of ± 20% of the length of the unit base 1 to be inserted. If it is longer than 20%, the heater may be disconnected, and if it is 20% or less, the heat capacity for heating is insufficient. As a means for driving the upper and lower unit bases 1 and 2 at the time of pressure bonding, driving by a cylinder, driving by a motor, or driving in which both are combined can be employed.

  FIG. 2 is a side view of the arrangement of the heater 9 in the crimping unit structure 10 shown in FIG. 1 and is disposed only on the upper portion of the unit base 1 on which the upper crimping tool 7 is held. An even number of heaters 9 are arranged equally on the left and right with respect to the center of the upper unit base 1 shown in FIG.

  The upper and lower crimping tools 7 and 8 were prepared as follows.

As main components, an Si ₃ N ₄ powder containing an α-Si ₃ N ₄ phase and a β-Si ₃ N ₄ phase at a predetermined ratio and having an average particle size of 0.5 microns, and an average particle size of 1 as a sintering aid Disperse and mix for 20 hours in a rubber lining pot containing ZrO ₂ balls with a purity of 99.5% or more in a methanol solvent by adding powder of Y ₂ O ₃ , AlN, MgO, TiN, etc. Went. After the obtained slurry was taken out, an alcohol-based binder was added and granulated and mixed in a nitrogen atmosphere with a closed spray dryer. A 4 × 5 × 45 mm bending test piece and Φ20 × 3 tmm thermal conductivity measurement sample are prepared from the obtained granulated powder by a die press, and after degreasing, in a nitrogen gas in a temperature range of 2023K to 2123K. Normal sintering was performed. A part of the sintered sample was subjected to HIP treatment using nitrogen gas in the temperature range of 1923K to 2023K.

FIG. 3 shows the change of the thermal expansion coefficient at each temperature of the obtained sample according to the present invention in comparison with Al ₂ O ₃ —TiC and SKD-60. As shown in the figure, the Si ₃ N ₄ based ceramic material according to the present invention has a temperature change of the thermal expansion coefficient of 1/5 or less of SKD-60, and 1/3 of Al ₂ O ₃ —TiC ceramics. It is shown below, and it is difficult to be affected by temperature change. This means that high accuracy at room temperature is maintained even at high temperatures.

Table 1 shows Sample No. The characteristics as the crimping tool of the crimping unit structure according to the present invention were evaluated for each of the compositions shown in 1-13. In the same table, sample No. Nos. 1 to 5 are examples of the present invention. 6-13 shows a comparison as a comparative example SUS304, SKD61 made of a metal, WC-Co cemented _{carbide, Al 2 O 3, Al 2} O 3 -TiC, the materials such as ZrO ₂ ceramic.

  The crimping tool material according to the present invention was prepared according to the above-described preparation method, and was ground into a shape suitable for the crimping tool having the crimping unit structure shown in FIGS. The crimping surface of the crimping tool material is processed to have a flatness of 2 μm or less and evaluated by an actual machine. Each evaluation result is shown in Table 1.

Flatness and coefficient of thermal expansion Since the working temperature of the crimping tool is usually 423 to 673K, the crimping working surface processed at room temperature is deformed due to thermal expansion at the working temperature. The deformation means deterioration of the flatness of the pressure-bonding surface to be transferred, so that the change in flatness from room temperature to high temperature needs to be as small as possible. The average coefficient of thermal expansion between 273 and 1273 K of the crimping tool of the present invention was 3.2 to 3.5 × 10 ⁻⁶ / K, which was extremely small as compared with the comparative example.

Since the crimping tool transmits pressure and adheres an object to be processed, it must have high resistance to pressure. That is, it is an application in which any shape of the pressure surface is not allowed to break. Accordingly, a 2R notch (groove) was machined in the center of the measurement surface (bottom surface) of the JIS bending test piece to measure the decrease in bending strength. As a result, a material having high strength is advantageous, but the degradation of Si ₃ N ₄ -based materials and ZrO ₂ -based materials from No. 1 to No. 5 is small among ceramics. Among the Si ₃ N ₄ -based materials of the present invention, α has a lower bending strength and higher bending strength than a material having many α-Si ₃ N ₄ phases or Si ₃ N ₄ ceramics composed of a single phase of β-Si ₃ N ₄ phase. It was found that the -β phase composite type Si ₃ N ₄ ceramic material is less preferable in strength reduction and has more preferable characteristics.

Sample No. in Table 1 No. 6 is the addition of SiC by 55 wt% (55 vol% in terms of conversion) for the purpose of dispersion strengthening. However, the denseness is not sufficient, the strength is low, the surface roughness is rough, and the like cannot be used. there were. Therefore, the _Si 3 _{N 4} component can be said that preferably at least 50% by volume.

Since the pressure tool is exposed to a high temperature of 423 to 673 K in an air atmosphere when thermocompression bonding is performed, there is a problem of oxidation. Oxidation causes damage to the surface due to alteration such as oxide generation due to oxidation of tool components and sublimation due to oxidation, which causes deterioration of flatness and surface roughness. As shown in Table 1, other than comparative Al ₂ O ₃ and ZrO ₂ were easily oxidized, and the Si ₃ N ₄ ceramic of the present invention showed the best results.

A Si ₃ N ₄ based ceramic sintered body according to the present invention was prepared and ground into a shape matching the crimp unit structure shown in FIGS. 1 and 2 to produce a crimp tool. The pressure-bonding surface to be used was processed to have a parallelism of 5 μm or less and a flatness of 2 μm or less, and evaluated with an actual machine.

Using four heaters 9 (cartridge type, diameter 8 mm, effective length 35 mm) shown in FIG. 1 arranged on the unit base 1 above, crimping tools 7 and 8 (length 100 mm, width 4 mm, height 15 mm) The composition No. in Table 1 was ground as 1 Si ₃ N ₄ base ceramics are screwed to the upper and lower unit bases 1 and 2 with the tool holders 3 and 4, and the crimping position of the glass substrate on which the FPC is temporarily fixed by the adhesive sheet is set at a predetermined position. These were placed between the crimping tools 7 and 8 and cured by pressurizing and heating under the conditions of 453K, 3.92 MPa and 20 seconds.

As a comparative example, evaluation was performed using Al ₂ O ₃ —TiC ceramics conventionally used for the above crimping tool. When n = 10 samples of Examples and Comparative Examples were prepared and used for 2000 hours under conditions of room temperature of 358K and humidity of 65%, the incidence of joint failure due to the crimping unit structure of the present invention was 0. On the other hand, it was 20 in the comparative example. In addition, when the pressure heating and rapid cooling cycle of cooling to room temperature after holding for 20 seconds under the condition of 453K and 3.92 MPa was repeated 590 cycles, the incidence of bonding failure due to the crimping unit structure of the present invention was 0. On the other hand, in the case of the comparative example, it was 30.

The example of the crimping unit structure of this invention is shown. It is the figure which looked at the arrangement | positioning of the heater in the crimping | compression-bonding unit structure shown in FIG. 1 from the side surface. It is a figure which shows the thermal expansion coefficient of the crimping | compression-bonding tool material which concerns on this invention.

Explanation of symbols

1, 2: Unit base material 3, 4: Tool holder 5, 6: Screw 7, 8: Crimping tool 9: Heater 10: Crimp unit structure

Claims (1)

Two crimping tools arranged up and down across the material to be crimped, and an upper and lower holding part that holds the crimping surfaces of the two crimping tools in parallel,
An even number of heaters of the cartridge type are arranged evenly on the left and right with respect to the center of the holding part only on the upper holding part,
The effective length of the cartridge-type heater is in a range of ± 20% of the depth length of the cartridge-type heater inserted into the holding portion,
The crimping tool, becomes a _Si 3 _{N 4} from _Si 3 _{N 4} group ceramic material containing 50% by volume or more,
This Si ₃ N ₄ based ceramic material has two-phase crystals of α-Si ₃ N ₄ phase and β-Si ₃ N ₄ phase, and the proportion of α-Si ₃ N ₄ phase in the two phases is volume%. 12 or more and 39.8 or less ,
The α-Si ₃ N ₄ is a part of Si ₃ N ₄ substituted with Y, Mg, O or Al,
_β-Si 3 _{N 4} phase state, and are not part the _Si 3 _{N 4} is replaced by O or Al,
and,
The Si ₃ N ₄ based ceramic material has a pressure bonding unit structure in which the pressure bonding surface is processed to have a parallelism of 5 μm or less and a flatness of 2 μm or less .

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