JP2015191928A - Method of determining bonding temperature condition of electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of determining a bonding temperature condition of an electronic component capable of easily determining a bonding temperature condition at thermocompression bonding of the electronic component.SOLUTION: A method of determining a bonding temperature condition of an electronic component at the time when the electronic component is thermocompression-bonded to an adherend while interposing an adhesive film, includes: a bonding temperature determination material selection step S11 of selecting a plurality of bonding temperature determination materials that have different melting temperatures; a pattern formation step S12 of forming a pattern by the selected bonding temperature determination materials, that can be confirmed visually, on any one of respective opposed surfaces of the electronic component and the adherend; a thermocompression bonding step S13 of thermocompression-bonding the electronic component to the adherend after the formation of the pattern; a molten state determination step S14 of determining a molten state of the pattern by the bonding temperature determination materials after the thermocompression bonding; and a bonding temperature determination step S15 of determining a bonding temperature at the thermocompression bonding on the basis of the determination result.

Description

  The present invention relates to a method for determining a bonding temperature condition when an electronic component such as an IC chip is thermocompression bonded to a substrate or the like.

  Conventionally, a tape-like connection in which a curable resin in which conductive particles are dispersed is applied to a release film when electronic components such as IC chips are thermocompression-bonded to a substrate, etc., or during the manufacture of LDC (Liquid Crystal Display) Materials (for example, anisotropic conductive film (ACF) (hereinafter also referred to as “adhesive film”)) are used. This anisotropic conductive film is used, for example, when various terminals are bonded and electrically connected.

  When determining the bonding temperature condition of the anisotropic conductive film, for example, after setting the temperature and pressure of the heating press device (heating bonder), it is heated (blank), and the temperature reached is measured with a thermocouple. Then, the temperature is estimated, the anisotropic conductive film is actually pressure-bonded, and the melting and bonding state of the conductive particles is confirmed. In recent years, thinning of panels and LCDs has been progressing in order to reduce the weight and size of equipment, and the thinning of the panel increases the distortion of thermal effects during mounting. For this reason, it is necessary to cure the ACF even at a low temperature, and it is important to appropriately determine the ultimate temperature.

  However, in the measurement of the ultimate temperature with a thermocouple, a deviation from the actual temperature may occur. In addition, if crimping is continuously performed on the production line, temperature deviation may gradually occur. To correct this deviation, it is necessary to frequently stop the production line and perform temperature measurement. There was a problem. Furthermore, although the presence or absence of a metal bond can be confirmed by press-bonding an anisotropic conductive film containing conductive particles, it has been difficult to determine whether the temperature is excessively applied.

  If the temperature is excessively applied, the thermosetting reaction of the binder proceeds before the binder in the anisotropic conductive film sufficiently flows, and the conductive particles cannot be captured between the terminals of the electronic component. Thereafter, although the conductive particles melt, they are not sufficiently in contact with the terminals of the electronic component, so that a sufficient metal bond cannot be formed. For this reason, the conduction reliability of the connection structure in which the terminals of the electronic components are connected to each other is deteriorated. The temperature is usually measured by inserting a small thermocouple into the measurement part, but it cannot be confirmed with an actual product.

  In order to solve such a problem, as a conventional example, for example, Patent Document 1 proposes a method for determining a bonding temperature condition during thermocompression bonding. Specifically, in order to confirm the bonding temperature condition (attainment temperature) at the time of pressure bonding of the anisotropic conductive film, interposing an adhesive film containing a plurality of metal particles having different solidus temperature and particle size, Electronic components are thermocompression bonded. And the joining temperature conditions at the time of thermocompression bonding are determined by observing the molten state of the metal particles in the adhesive film after thermocompression bonding.

JP 2013-105886 A

  In general, in the process of manufacturing a connection structure including an electronic component and a substrate, it is preferable that the bonding temperature condition by thermocompression bonding can be easily determined in order to increase the production efficiency. However, in the electronic component joining temperature condition determination method disclosed in Patent Document 1, in order to make a determination based on the molten state of the metal particles in the ACF, the heated and pressure-bonded portion is peeled off by hand, for example, enlarged with an optical microscope or the like. Thus, it is necessary to determine whether or not the fine metal particles are melted. In other words, Patent Document 1 does not describe a method by which the melted state can be easily confirmed by visual recognition without enlarging.

  The present invention has been proposed in view of such a situation, and it is possible to easily determine the bonding temperature condition at the time of thermocompression bonding of an electronic component by enabling easy confirmation by visual recognition. An object of the present invention is to provide a method for determining a joining temperature condition of an electronic component.

  One aspect of the present invention is a method for determining a bonding temperature condition of an electronic component when an electronic component is thermocompression bonded to an adherend with an adhesive film interposed therebetween, and a plurality of bonding temperature determination materials having different melting temperatures are selected. A bonding temperature determining material selecting step, a pattern forming step of forming a pattern visible by the selected bonding temperature determining material on either one of the electronic component and the adherend, respectively, Based on the determination result, a thermocompression bonding step of thermocompression bonding the electronic component to the adherend after formation, a melting state determination step of determining a melting state of the pattern by the bonding temperature determination material after the thermocompression bonding, and And a bonding temperature determining step for determining a bonding temperature during thermocompression bonding.

  According to one aspect of the present invention, by forming a pattern of a bonding temperature determination material having a visible size, melting of the pattern can be easily confirmed visually, and the bonding temperature at the time of thermocompression bonding of an electronic component Conditions can be determined accurately.

  At this time, in one aspect of the present invention, in the melting state determination step, when there are at least one molten bonding temperature determination material and at least one bonding temperature determination material that does not melt among the plurality of bonding temperature determination materials, the bonding temperature Move to the decision process.

  If it does in this way, it can determine with the ultimate temperature at the time of thermocompression bonding being more than melting | fusing point of the fuse | melting joining temperature determination material, and less than melting | fusing point of the joining temperature determination material which is not fuse | melted.

  Further, in one aspect of the present invention, in the joining temperature determination material selection step, the components may be adjusted so that the difference in melting temperature between the plurality of joining temperature determination materials is 1 ° C. or more.

  In this way, the difference in melting temperature becomes large, and it becomes easy to distinguish between a joining temperature determining material that melts and a joining temperature determining material that does not melt, and it is easy to determine the ultimate temperature.

  In one mode of the present invention, in a pattern formation process, a pattern may be formed so that it may have a plurality of shapes according to the kind of joining temperature judging material.

  Thereby, the joining temperature determination material which has different melting temperature can be easily identified by the difference in pattern shape, and discrimination | determination of ultimate temperature becomes easy.

  Further, according to one embodiment of the present invention, in the pattern formation step, the pattern may be formed to have a gap through which light is transmitted, and in the melting state determination step, the melting state may be determined based on whether light is transmitted. .

  In this way, since it is possible to determine the presence or absence of melting based on the presence or absence of light transmission, it is possible to determine the melting of the bonding temperature determination material even visually.

  In one embodiment of the present invention, in the bonding temperature determination material selection step, the bonding temperature determination material may select at least one of solder or an organic film.

  In this way, by using solder or an organic film, it is easy to adjust the components, and a bonding temperature determination material having a plurality of melting temperatures can be created.

  In one embodiment of the present invention, the adhesive film may be an anisotropic conductive film.

  If it does in this way, joining temperature can be judged on the same conditions as the time of actually joining an electronic component via an anisotropic conductive film.

  In one embodiment of the present invention, the adherend may be a member formed of a light-transmitting material.

  In this way, by using a translucent member, it can be confirmed through the translucent member, and it is not necessary to peel off the electronic member from the adherend, and non-destructive confirmation is possible. Become.

  According to the present invention, it is possible to easily confirm the melting state of the bonding temperature determination material in the adhesive film after thermocompression bonding by forming a pattern of the bonding temperature determination material having a size that can be visually recognized. For this reason, since it is possible to specify the molten bonding temperature determination material and the unmelted bonding temperature determination material, it is possible to accurately determine the bonding temperature condition during thermocompression bonding, that is, the ultimate temperature during thermocompression bonding. .

It is a flowchart for demonstrating the outline of the joining temperature condition determination method of the electronic component which concerns on one Embodiment of this invention. It is a top view for demonstrating an example of the thermocompression-bonding process in the joining temperature condition determination method of the electronic component which concerns on one Embodiment of this invention. It is sectional drawing for demonstrating an example of the thermocompression-bonding process in the joining temperature condition determination method of the electronic component which concerns on one Embodiment of this invention. It is a top view for demonstrating an example of the thermocompression-bonding process in the joining temperature condition determination method of the other electronic component which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail in the following order with reference to the drawings. The present embodiment described below does not unduly limit the contents of the present invention described in the claims, and all the configurations described in the present embodiment are essential as means for solving the present invention. Not necessarily.
1. 1. Outline of the present invention 2. Joining temperature determination material selection step Pattern formation step 4. 4. Thermocompression bonding step Melting state determination step 6. Joining temperature determination process

<1. Summary of the present invention>
The process of the electronic component joining condition determination method according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a flowchart for explaining an outline of a method for determining a bonding temperature condition of an electronic component according to an embodiment of the present invention.

  In the electronic component bonding condition determination method according to an embodiment of the present invention, first, a plurality of bonding temperature determination materials having different melting temperatures are selected in the bonding temperature determination material selection step S11. The type of the bonding temperature determination material is not particularly limited as long as the melting temperature (melting point, solidus temperature, etc.) is known, and examples thereof include solder and an organic film.

  Next, in the pattern formation step S12, as shown in FIG. 2, the pattern formed by the bonding temperature determination materials 13, 14, and 15 is either one of the opposing surfaces of the electronic component 11 and the adherend 16 (in the case of an electronic component). The surface 11a is formed on the surface 16a) in the case of an adherend. Examples of the pattern forming method include a screen printing method and a photolithography method.

  When the pattern is formed, in the thermocompression bonding step S <b> 13, as shown in FIG. 3, the electronic component 11 is thermocompression bonded to the adherend 16 with the adhesive film 19 interposed therebetween, thereby creating the connection structure 10. Examples of the adhesive film 19 used at this time include an anisotropic conductive film (ACF) composed of a binder 17 and metal particles 18.

  In the melting state determination step S14, it is determined whether or not the pattern formed by the bonding temperature determination materials 13, 14, and 15 is melted with respect to the connection structure 10 after thermocompression bonding. According to one aspect of the present invention, it is possible to easily confirm the melting of the pattern by visual observation by forming the pattern of the bonding temperature determination materials 13, 14, and 15 having a size that can be visually recognized. The visually recognizable size is, for example, about 0.1 mm.

  If the temperature can be determined in the molten state determination step S14, the process proceeds to the bonding temperature determination step S15, and the bonding temperature condition of the electronic component is determined. By actually forming a pattern of a plurality of bonding temperature determination materials 13, 14, and 15 on the electronic component 11 and the adherend 16 and visually confirming the presence or absence of melting, it is possible to determine the bonding temperature condition with high accuracy. Become. In the melt state determination step S14, if the temperature cannot be determined, the process returns to the bonding temperature determination material selection step S11 and the bonding temperature condition is set again.

  As described above, in the electronic component joining temperature condition determining method according to the present embodiment, a pattern of the plurality of joining temperature determination materials 13, 14, 15 is formed on the electronic component 11 or the adherend 16, and the adhesive film 19 is attached. The electronic component 11 and the adherend 16 are thermocompression bonded by interposing them. And the joining conditions at the time of thermocompression bonding are determined by visually recognizing the molten state of the pattern after thermocompression bonding. Thereby, for example, it becomes possible to measure the temperature reached at the time of thermocompression bonding more easily and accurately than the measurement of the pressure bonding temperature by a conventional thermocouple. Further, by using the plurality of bonding temperature determination materials 13, 14, and 15, a finer temperature range can be specified, and as a result, the ultimate temperature at the time of thermocompression bonding can be determined accurately and quickly.

  Hereinafter, each step will be described in more detail.

<2. Joining temperature judgment material selection process>
In the bonding temperature determination material selection step S11, a plurality of bonding temperature determination materials having different melting temperatures are selected in order to determine a bonding condition at the time of thermocompression bonding, for example, an ultimate temperature at the time of thermocompression bonding.

  As the bonding temperature determination materials 13, 14, and 15, it is preferable to prepare a plurality of materials having a melting temperature close to the target temperature at the time of target thermocompression bonding. For example, with a target temperature at the time of thermocompression bonding as a reference temperature, a joining temperature determination material having a melting temperature lower than the reference temperature and a joining temperature determination material having a melting temperature higher than the reference temperature can be selected. These bonding temperature determination materials are preferably component-adjusted so that the difference in melting temperature is 1 ° C. or more. In this way, by using a plurality of bonding temperature determination materials 13, 14, and 15 having a difference in melting temperature of 1 ° C. or more, the molten bonding temperature determination material and the unmelted bonding temperature determination material can be confirmed more accurately. Therefore, the ultimate temperature at the time of thermocompression bonding can be determined more easily.

  In addition, the types of the bonding temperature determination materials 13, 14, and 15 may be two or more types, and it is preferable to use three or more types in order to confirm the ultimate temperature at the time of thermocompression bonding more reliably. For example, when the temperature range of the adhesive film 19 is 150 to 190 ° C., it is preferable to use materials having melting points of 140, 160, and 190 ° C. as the bonding temperature determination materials 13, 14, and 15, respectively.

  The type of the bonding temperature determination material is not particularly limited, but it is preferable to select at least one of solder or an organic film. Since solder has a relatively low melting temperature (solidus temperature), it can be thermocompression bonded at a low temperature. Moreover, the solder can adjust the melting temperature (solidus temperature) precisely by combining various composition ratios. The solder can be obtained, for example, by spraying a molten alloy into water from a predetermined nozzle and rapidly solidifying it by a normal water atomizing method.

  As a kind of solder, in addition to a general solder composed of Sn and Pb, a metal selected from In, Bi, Ag, Sb, Zn, Cu, Au, Al, As, Cd, Fe, Ni and the like is contained. High temperature solder, low melting point solder, or the like can be used. Thus, solder is preferable as a bonding temperature determination material because the melting temperature (solidus temperature) can be adjusted to various temperatures by changing the contained metal and the blending ratio of the contained metal.

  The organic film may be of any type as long as it has a known melting point, but may contain, for example, a decolorizable dye, a curable organic resin, a curing agent, and conductive particles. Thus, it is preferable that a change that can be visually confirmed such as a change in color or a change in hardness occurs when the temperature reaches a predetermined temperature. Specific examples of the organic film include polyimide, polyester, acrylic polymer, and the like. These polymer organic films can also have a melting point adjusted, for example, by adjusting the degree of polymerization.

<3. Pattern formation process>
In the pattern formation step S12, as shown in FIG. 2, the pattern formed by the bonding temperature determination materials 13, 14, and 15 is either one of the opposing surfaces of the electronic component 11 and the adherend 16 (in the case of an electronic component, the surface 11a, In the case of an adherend, it is formed on the surface 16a).

  Here, examples of the electronic component 11 and the adherend 16 include a semiconductor chip such as an IC chip and an LSI (Large Scale Integration) chip, a semiconductor element such as a chip capacitor, a flexible printed board, a rigid board, and a glass board. be able to. An embodiment having a plurality of panels such as LDC (Liquid Crystal Display) is also included in this embodiment.

  As a pattern formation method, a general screen printing method or a photolithography method can be used, but either one of the opposing surfaces of the electronic component 11 and the adherend 16 (the surface 11a in the case of an electronic component, In the case of an adherend, the method is not particularly limited as long as a pattern can be formed on the surface 16a) by the bonding temperature determination materials 13, 14, and 15.

  The pattern need not have a different shape as long as the position is determined. However, in order to make it easier to see, the shape may be changed for each pattern having a different melting temperature. For example, a pattern having a plurality of shapes may be formed by using a low melting point bonding temperature determination material as a rectangle and a high melting point bonding temperature determination material as a triangle. Thereby, the joining temperature determination material which has different melting temperature can be easily identified by the difference in pattern shape, and discrimination | determination of ultimate temperature becomes easy.

  The size of the pattern is determined by the size of the target electronic component and the size outside the terminal area. As a matter of course, a short circuit occurs when the bonding temperature determining materials 13, 14, and 15 that have spread due to the crimping contact the terminal 12, and it is necessary to design in consideration of this point. Two or more types of bonding temperature determination materials having different melting temperatures may be used. However, when it is desired to confirm the pressure bonding conditions more reliably, it is preferable to form a pattern using three or more types of bonding temperature determination materials.

  Moreover, as shown in FIG. 4, it can also form so that the joining temperature determination materials 23 and 25 may consist of a some linear pattern so that it may have the clearance gap which permeate | transmits light. In this way, in the melting state determination step S14 described later, the presence or absence of melting can be determined based on the presence or absence of light transmission, so that the melting of the joining temperature determination material can also be determined visually.

<4. Thermocompression bonding process>
In the thermocompression bonding step S13, after the pattern is formed, the adhesive film 19 is interposed between the electronic component 11 and the adherend 16 and the electronic component 11 and the adherend 16 are connected by thermocompression bonding.

  As the adhesive film 19 interposed in the thermocompression bonding step, for example, an anisotropic conductive film (ACF) can be used. The adhesive film 19 is formed in a state where metal particles 18 are dispersed in a binder (adhesive) 17.

  As the binder 17, for example, a material containing a film-forming resin, a thermosetting resin, a latent curing agent, a silane coupling agent, or the like can be used.

  As the metal particles 18, various conductive particles can be used. For example, particles of various metals such as nickel, iron, copper, aluminum, tin, lead, chromium, cobalt, silver, and gold, particles of metal alloys such as solder, and particles of metal oxide can be used. Moreover, the thing which coat | covered the metal on the surface of particle | grains, such as carbon, a graphite, glass, a ceramic, a plastics, and what further coat | covered the insulating thin film on the surface of these particles can be used. When the metal particles 18 are obtained by coating the surfaces of the resin particles with metal, examples of the resin particles include epoxy resins, phenol resins, acrylic resins, acrylonitrile / styrene (AS) resins, benzoguanamine resins, and divinylbenzene resins. Particles such as styrene resin can be used.

  The thermocompression bonding between the electronic component 11 and the adherend 16 can be performed using, for example, a heat pressing device. The thermocompression bonding sets the conditions of the heating and pressing device, for example, temperature, pressure, and time, and the curing temperature of the thermosetting resin in the adhesive film 19 while pressing the upper surface of the electronic component 11 with a predetermined pressure by the heating and pressing device. It is performed by heating at the above temperature. Although the heating temperature at the time of thermocompression bonding differs depending on the type of thermosetting resin, for example, the temperature is about 140 to 230 ° C. Moreover, the pressure at the time of thermocompression bonding shall be about 2-50 MPa, for example. The time for thermocompression bonding is preferably 5 to 30 seconds, for example. By setting the time for thermocompression bonding to 5 to 30 seconds, the fluidity in the adhesive film 19 can be prevented from becoming insufficient, and the workability can be prevented from being lowered.

<5. Melting state determination process>
In the melting state determination step S14, it is determined whether or not the pattern formed by the bonding temperature determination materials 13, 14, and 15 is melted with respect to the connection structure 10 after thermocompression bonding.

  For example, whether the pattern is melted by manually peeling off the heat-pressed portion of the heat-bonded adhesive film 19 and visually observing the pattern of the bonding temperature determination materials 13, 14, 15 in the adhesive film 19. Confirm.

  Further, the adherend 16 may be a member formed of a light-transmitting material. By using a light-transmitting member, it can be confirmed through the light-transmitting member, and the electronic component 11 does not need to be peeled off from the adherend 16 and can be confirmed nondestructively. Examples of the light-transmitting material include glass.

  As to whether or not the bonding temperature determination materials 13, 14, and 15 are melted, the shape of any of the bonding temperature determination materials 13, 14, and 15 is collapsed and the area is clearly larger than before the thermocompression bonding. Can be determined that the joining temperature determination material is melted. In this way, by visually recognizing the molten state of the bonding temperature determination materials 13, 14, and 15 after thermocompression bonding, it is possible to identify the molten bonding temperature determination material and the unmelted bonding temperature determination material.

  For example, when there is at least one molten bonding temperature determination material and at least one bonding temperature determination material that does not melt among the plurality of bonding temperature determination materials, the process can proceed to a bonding temperature determination step described later. In this case, it is possible to determine that the ultimate temperature at the time of thermocompression bonding is equal to or higher than the melting point of the molten bonding temperature determination material and lower than the melting point of the bonding temperature determination material that does not melt.

  In addition, when all of the plurality of bonding temperature determination materials are melted or not melted at all, the temperature range of the reached temperature at the time of thermocompression bonding cannot be specified accurately. Returning to step S11, it is necessary to select the joining temperature determination material again or to change the temperature condition at the time of thermocompression bonding.

  For example, in the molten state determination step S14, when all the bonding temperature determination materials 13, 14, and 15 are melted, it can be estimated that the temperature reached at the time of thermocompression bonding is excessive.

  In the above description, in the melting state determination step S14, the melting state of the bonding temperature determination materials 13, 14, and 15 is visually observed. However, the present invention is not limited to this. For example, the pattern formed by the bonding temperature determination materials 13, 14, and 15 may be enlarged and visually confirmed using an optical microscope, or the area value of the pattern formed by the bonding temperature determination materials 13, 14, and 15 may be calculated by image processing. Thus, it is possible to identify the molten bonding temperature determination material and the unmelted bonding temperature determination material, and determine the ultimate temperature at the time of thermocompression bonding.

  In the pattern formation step S13, as shown in FIG. 4, when the bonding temperature determination materials 23 and 25 are formed to have a plurality of linear patterns so as to have a gap for transmitting light, the sensor is The presence or absence of melting of the bonding temperature determination materials 23 and 25 can also be determined based on the presence or absence of light transmission. In other words, if it is not melted, the pattern gap remains, so that light is transmitted. If it is melted, the pattern gap is filled with the bonding temperature determination material by melting, so that the light is transmitted. No longer. By doing in this way, the presence or absence of the melting of the joining temperature determination materials 23 and 25 can also be mechanically determined by a sensor or the like, and accurate determination is possible.

<6. Joining temperature determination process>
In the joining temperature determination step S15, heating when the electronic component 11 is thermocompression bonded to the adherend 16 via the adhesive film 19 based on the determination result of the reached temperature at the time of thermocompression determined in the melt state determination step S14. Determine the joining temperature of the pressing device. If the bonding temperature is determined, the electronic component 11 is thermocompression bonded to the adherend 16 via the adhesive film 19 on the actual manufacturing line based on the determined bonding temperature condition, and the connection structure 10 is manufactured. Go.

  In the bonding temperature determination step S15, the conditions of the heating and pressing device are changed based on the reached temperature determined in the molten state determination step S14 as necessary, and the thermocompression bonding between the electronic component 11 and the adherend 16 is performed again. You may make it perform.

  Further, in the above description, the optimum ultimate temperature when the pressure and the thermocompression bonding time are fixed is determined as the joining condition during thermocompression bonding, but the present invention is not limited to this example. For example, as a bonding condition at the time of thermocompression bonding, an optimal thermocompression bonding time when the ultimate temperature and pressure are constant, and an optimal pressure when the ultimate temperature and thermocompression bonding time are constant may be determined. .

  Examples of the present invention will be described below. The present invention is not limited to these examples. In the following examples, solder was selected as the bonding temperature determination material, and an anisotropic conductive film (ACF) was used as the adhesive film.

(Production of solder)
By a normal water atomizing method, a molten alloy having the metal species and ratio shown in Table 1 is sprayed into water from a predetermined nozzle and rapidly solidified to obtain five types of solders (a) to (e). It was. Table 1 shows melting temperatures (solidus temperatures) of the solders (a) to (e).

(Preparation of anisotropic conductive film)
40 parts by weight of a phenoxy resin (YP-50, Nippon Steel Chemical), 18 parts by weight of a liquid epoxy compound (EP828, Mitsubishi Chemical), 40 parts by weight of a liquid epoxy compound (Novacure 3951HP, Asahi Kasei), and a silane coupling agent ( A-187, Momentive Performance Materials) 1 part by weight was mixed with 35 parts by weight of conductive particles (Bright 20GNR, Nippon Chemical). 100 parts by weight of the above formulation is dissolved in 100 parts by weight of toluene, mixed, applied onto a release PET sheet using a bar coater, dried at 60 ° C. for 10 minutes to volatilize the solvent, and anisotropy of 30 μm thickness. A conductive film was obtained.

<Example 1>
In Example 1, only the solder (a) is metal-bonded using the three types of solder (a), solder (b), and solder (c) when thermocompression bonding is performed with the anisotropic conductive film interposed therebetween. The temperature (tool temperature) of the optimum heating and pressing apparatus to be made was determined. The solder pattern is a solder of 50 μm × 1 mm and 10 μm thick on each of the solder (a), the solder (b), and the solder (c) using a screen printing method on the 1 mm end side from the terminal portion of the flexible printed circuit board. A pattern was formed.

(Measurement 1)
Using the anisotropic conductive film, a flexible printed circuit board for conducting reliability evaluation with a 50 μm pitch (L / S = 25 μm / 25 μm) and a terminal part of the glass substrate were connected. At this time, a 200 μm thick silicone sheet was used as a buffer material. A heat press bonder (Dexerials Co., Ltd.) was used for 10 seconds at 400 ° C. and 3 MPa, and then the pressure was released to obtain a connection structure. About the obtained connection structure, the shape and magnitude | size of the solder pattern in an anisotropic conductive film were observed, the melted solder pattern was specified, and the ultimate temperature at the time of thermocompression bonding was confirmed.

  As a result, the solder (a) was melted, the solder (b) was not melted, and the solder (c) was not melted. From this result, the ultimate temperature at the time of thermocompression bonding in Measurement 1 was 198 ° C. or higher and less than 217 ° C., and it was confirmed that the ultimate temperature at the thermocompression bonding was appropriate.

(Measurement 2)
A connection structure was obtained in the same manner as in Measurement 1 except that a heat press bonder was used for 10 seconds at 430 ° C. and 3 MPa. About the obtained connection structure, it carried out similarly to the measurement 1, and observed the molten state of the solder pattern in the anisotropic conductive film after thermocompression bonding.

  As a result, the solder (a) was melted, the solder (b) was also melted, and the solder (c) was not melted. From this result, the temperature reached at the time of thermocompression bonding in Measurement 2 was 217 ° C. or more and less than 221 ° C., and it was confirmed that the temperature reached at the time of thermocompression bonding was excessive.

<Example 2>
In Example 2, when using the two types of solder (d) and solder (e) and thermocompression bonding with the anisotropic conductive film interposed therebetween, the optimum heat pressing for bonding only the solder (d) to the metal The temperature of the device (tool temperature) was determined. As the solder pattern, a solder pattern having a thickness of 50 μm × 1 mm and a thickness of 10 μm was formed for each of the solder (d) and the solder (e) by using a screen printing method on the 1 mm end side from the terminal portion of the flexible printed board.

(Measurement 3)
Using the anisotropic conductive film, a flexible printed circuit board for conducting reliability evaluation with a 50 μm pitch (L / S = 25 μm / 25 μm) and a terminal part of the glass substrate were connected. At this time, a 200 μm thick silicone sheet was used as a buffer material. A heat press bonder (manufactured by Dexerials Co., Ltd.) was used for 10 seconds at 300 ° C. and 3 MPa, and then the pressure was released to obtain a connection structure. About the obtained connection structure, the shape and magnitude | size of the solder pattern in an anisotropic conductive film were observed, the melted solder pattern was specified, and the ultimate temperature at the time of thermocompression bonding was confirmed.

  As a result, the solder (d) was melted and the solder (e) was not melted. From this result, the ultimate temperature at the time of thermocompression bonding in Measurement 3 was 130 ° C. or higher and less than 138 ° C., and it was confirmed that the ultimate temperature at the thermocompression bonding was appropriate.

(Measurement 4)
A connection structure was obtained in the same manner as in Measurement 3, except that the heat pressing was performed at 330 ° C. and 3 MPa for 10 seconds using a heat pressing bonder. About the obtained connection structure, it carried out similarly to the measurement 1, and observed the molten state of the solder pattern in the anisotropic conductive film after thermocompression bonding.

  As a result, the solder (d) was melted and the solder (e) was also melted. From this result, the ultimate temperature at the time of thermocompression bonding in Measurement 4 was 138 ° C. or higher, and it was confirmed that the ultimate temperature at the thermocompression bonding was excessive.

<Example 3>
In Example 3, the presence or absence of melting of the solder pattern was determined using a sensor. In Example 3, when using the two types of solder (d) and solder (e) and thermocompression bonding with the anisotropic conductive film interposed therebetween, the optimum heat pressing for bonding only the solder (d) to the metal The temperature of the device (tool temperature) was determined. As for the solder pattern, ten 25 μm solder patterns were formed on the flexible printed circuit board for each of the solder (d) and the solder (e) using a screen printing method.

(Measurement 5)
Using the anisotropic conductive film, a flexible printed circuit board for conducting reliability evaluation with a 50 μm pitch (L / S = 25 μm / 25 μm) and a terminal part of the glass substrate were connected. At this time, a 200 μm thick silicone sheet was used as a buffer material. A heat press bonder (manufactured by Dexerials Co., Ltd.) was used for 10 seconds at 300 ° C. and 3 MPa, and then the pressure was released to obtain a connection structure. About the obtained connection structure, the presence or absence of the light transmission of each solder pattern was measured using the sensor (EX3-DAI11-S, OMRON).

  As a result, the solder (d) did not transmit light, and the solder (e) transmitted light. That is, the solder (d) was melted and the solder (e) was not melted. From this result, the ultimate temperature at the time of thermocompression bonding in Measurement 5 was 130 ° C. or more and less than 138 ° C., and it was confirmed that the ultimate temperature at the thermocompression bonding was appropriate.

<Comparative Example 1>
(Measurement 6)
In measurement 6, a solder pattern having a thickness of 50 μm × 1 mm and 10 μm was formed on the 1 mm end side of the terminal portion of the flexible printed board by using screen printing only for the solder (a). Next, using the anisotropic conductive film, a flexible printed board for conductive reliability evaluation with a pitch of 50 μm (L / S = 25 μm / 25 μm) and a terminal portion of the glass substrate were connected. At this time, a 200 μm thick silicone sheet was used as a buffer material. A heat press bonder (Dexerials Co., Ltd.) was used for 10 seconds at 400 ° C. and 3 MPa, and then the pressure was released to obtain a connection structure. About the obtained connection structure, it carried out similarly to the measurement 1, and observed the molten state of the solder pattern in the anisotropic conductive film after thermocompression bonding.

  As a result, the solder (a) was melted. From this result, it was confirmed that the ultimate temperature at the time of thermocompression bonding in Measurement 5 was 198 ° C. or higher. However, it has not been possible to confirm whether the ultimate temperature during thermocompression bonding is appropriate or excessive.

(Measurement 7)
A connection structure was obtained in the same manner as in the measurement 6 except that a heat press bonder was used for 10 seconds at 430 ° C. and 3 MPa. About the obtained connection structure, it carried out similarly to the measurement 1, and observed the molten state of the solder pattern in the anisotropic conductive film after thermocompression bonding.

  As a result, the solder (a) was melted. From this result, it was confirmed that the ultimate temperature during thermocompression bonding in Measurement 7 was 198 ° C. or higher. However, it has not been possible to confirm whether the ultimate temperature during thermocompression bonding is appropriate or excessive.

(Measurement 8)
In measurement 8, a solder pattern having a thickness of 50 μm × 1 mm and a thickness of 10 μm was formed only on the solder (b) by using a screen printing method on the 1 mm end side of the terminal portion of the flexible printed board. Next, using the anisotropic conductive film, a flexible printed board for conductive reliability evaluation with a pitch of 50 μm (L / S = 25 μm / 25 μm) and a terminal portion of the glass substrate were connected. At this time, a 200 μm thick silicone sheet was used as a buffer material. A heat press bonder (Dexerials Co., Ltd.) was used for 10 seconds at 430 ° C. and 3 MPa, and then the pressure was released to obtain a connection structure. About the obtained connection structure, it carried out similarly to the measurement 1, and observed the molten state of the solder pattern in the anisotropic conductive film after thermocompression bonding.

  As a result, the solder (b) was melted. From this result, it was confirmed that the ultimate temperature during thermocompression bonding in Measurement 8 was 217 ° C. or higher. However, it has not been possible to confirm whether the ultimate temperature during thermocompression bonding is appropriate or excessive.

<Comparative Example 2>
(Measurement 9)
In measurement 9, a solder pattern having a thickness of 50 μm × 1 mm and 10 μm was formed only on the solder (d) on the 1 mm end side from the terminal portion of the flexible printed board by using a screen printing method. Next, using the anisotropic conductive film, a flexible printed board for conductive reliability evaluation with a pitch of 50 μm (L / S = 25 μm / 25 μm) and a terminal portion of the glass substrate were connected. At this time, a 200 μm thick silicone sheet was used as a buffer material. A heat press bonder (manufactured by Dexerials Co., Ltd.) was used for 10 seconds at 300 ° C. and 3 MPa, and then the pressure was released to obtain a connection structure. About the obtained connection structure, it carried out similarly to the measurement 1, and observed the molten state of the solder pattern in the anisotropic conductive film after thermocompression bonding.

  As a result, the solder (d) was melted. From this result, it was confirmed that the ultimate temperature during thermocompression bonding in Measurement 9 was 130 ° C. or higher. However, it has not been possible to confirm whether the ultimate temperature during thermocompression bonding is appropriate or excessive.

(Measurement 10)
A connection structure was obtained in the same manner as in measurement 9, except that the heat pressing was performed at 330 ° C. and 3 MPa for 10 seconds using a heat pressing bonder. About the obtained connection structure, it carried out similarly to the measurement 1, and observed the molten state of the solder pattern in the anisotropic conductive film after thermocompression bonding.

  As a result, the solder (d) was melted. From this result, it was confirmed that the ultimate temperature during thermocompression bonding in Measurement 10 was 130 ° C. or higher. However, it has not been possible to confirm whether the ultimate temperature during thermocompression bonding is appropriate or excessive.

(Measurement 11)
In measurement 11, a solder pattern having a thickness of 50 μm × 1 mm and a thickness of 10 μm was formed only on the solder (e) on the 1 mm end side from the terminal portion of the flexible printed board by using a screen printing method. Next, using the anisotropic conductive film, a flexible printed board for conductive reliability evaluation with a pitch of 50 μm (L / S = 25 μm / 25 μm) and a terminal portion of the glass substrate were connected. At this time, a 200 μm thick silicone sheet was used as a buffer material. A heat press bonder (manufactured by Dexerials Co., Ltd.) was used for heat press at 330 ° C. and 3 MPa for 10 seconds, and then the pressure was released to obtain a connection structure. About the obtained connection structure, it carried out similarly to the measurement 1, and observed the molten state of the solder pattern in the anisotropic conductive film after thermocompression bonding.

  As a result, the solder (e) was melted. From this result, it was confirmed that the ultimate temperature during thermocompression bonding in Measurement 10 was 138 ° C. or higher. However, it has not been possible to confirm whether the ultimate temperature during thermocompression bonding is appropriate or excessive.

  Table 2 shows a summary of the results of the method for determining the joining conditions for electronic components in Example 1, Example 2, Example 3, Comparative Example 1 and Comparative Example 2.

  As described above, in this embodiment, a solder pattern after thermocompression bonding is performed by thermocompression bonding between terminals by interposing a pattern of a plurality of solders having different melting temperatures (solidus temperature) and an anisotropic conductive film. The molten state of was observed. By observing the molten state of the solder pattern after thermocompression bonding, it was possible to identify the molten solder and the unmelted solder, and to determine whether the temperature was excessively applied. Therefore, it has been found that in the electronic component joining temperature condition determining method according to one embodiment of the present invention, the ultimate temperature at the time of thermocompression bonding can be accurately determined.

  10, 20 connection structure, 11, 21 electronic component, 12, 22 terminal, 13, 14, 15, 23, 24, 25 bonding temperature determination material, 16, 26 adherend, 17 binder, 18 metal particles, 19 adhesion the film

Claims (8)

A method for determining a bonding temperature condition of an electronic component when an electronic component is thermocompression bonded to an adherend with an adhesive film interposed therebetween,
A bonding temperature determination material selection step of selecting a plurality of bonding temperature determination materials having different melting temperatures;
A pattern forming step of forming a visible pattern by the selected bonding temperature determination material on either one of the opposing surfaces of the electronic component and the adherend, and
A thermocompression bonding step of thermocompression bonding the electronic component to the adherend after forming the pattern;
A melting state determination step of determining a melting state of the pattern by the bonding temperature determination material after the thermocompression bonding;
A method for determining a bonding temperature condition for an electronic component, comprising: a bonding temperature determination step for determining a bonding temperature during thermocompression bonding based on the determination result.   In the melting state determination step, when at least one of the plurality of bonding temperature determination materials includes a molten bonding temperature determination material and an unmelted bonding temperature determination material, the process proceeds to the bonding temperature determination step. Item 8. A method for determining a bonding temperature condition of an electronic component according to Item 1.   The method for determining a bonding temperature condition for an electronic component according to claim 1 or 2, wherein, in the bonding temperature determination material selection step, components are adjusted so that a difference in melting temperature of the plurality of bonding temperature determination materials is 1 ° C or more.   4. The method for determining a bonding temperature condition for an electronic component according to claim 1, wherein, in the pattern formation step, the pattern is formed so as to have a plurality of shapes according to the type of the bonding temperature determination material. 5.   The said pattern formation process WHEREIN: The said pattern is formed so that it may have the clearance gap which permeate | transmits light, In the said melt state determination process, a melt state is determined by the presence or absence of light transmission. Method for determining bonding temperature conditions for electronic components.   6. The method of determining a bonding temperature condition for an electronic component according to claim 1, wherein, in the bonding temperature determination material selection step, the bonding temperature determination material selects at least one of solder and an organic film. .   The method for determining a bonding temperature condition for an electronic component according to claim 1, wherein the adhesive film is an anisotropic conductive film.   The method for determining a bonding temperature condition for an electronic component according to claim 1, wherein the adherend is a member formed of a light-transmitting material.

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